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linux_dsm_epyc7002/include/asm-generic/vmlinux.lds.h

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Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
/*
* Helper macros to support writing architecture specific
* linker scripts.
*
* A minimal linker scripts has following content:
* [This is a sample, architectures may have special requiriements]
*
* OUTPUT_FORMAT(...)
* OUTPUT_ARCH(...)
* ENTRY(...)
* SECTIONS
* {
* . = START;
* __init_begin = .;
* HEAD_SECTION
* INIT_TEXT_SECTION(PAGE_SIZE)
* INIT_DATA_SECTION(...)
* PERCPU(PAGE_SIZE)
* __init_end = .;
*
* _stext = .;
* TEXT_SECTION = 0
* _etext = .;
*
* _sdata = .;
* RO_DATA_SECTION(PAGE_SIZE)
* RW_DATA_SECTION(...)
* _edata = .;
*
* EXCEPTION_TABLE(...)
* NOTES
*
* __bss_start = .;
* BSS_SECTION(0, 0)
* __bss_stop = .;
* _end = .;
*
* /DISCARD/ : {
* EXIT_TEXT
* EXIT_DATA
* *(.exitcall.exit)
* }
* STABS_DEBUG
* DWARF_DEBUG
* }
*
* [__init_begin, __init_end] is the init section that may be freed after init
* [_stext, _etext] is the text section
* [_sdata, _edata] is the data section
*
* Some of the included output section have their own set of constants.
* Examples are: [__initramfs_start, __initramfs_end] for initramfs and
* [__nosave_begin, __nosave_end] for the nosave data
*/
#include <linux/section-names.h>
Add new HEAD_TEXT_SECTION macro. This patch is preparation for replacing all uses of ".head.text" or ".text.head" in the kernel with macros, so that the section name can later be changed without having to touch a lot of the kernel. Since some linker scripts do more complex things than referencing HEAD_TEXT, we add a HEAD_TEXT_SECTION macro that just contains the actual name. I've defined HEAD_TEXT_SECTION in a new header, include/linux/section-names.h, so that this section name only needs to appear in one place. I anticipate creating similar macro structures for a number of other section names. The long-term goal here is to be able to change the kernel's magic section names to those that are compatible with -ffunction-sections -fdata-sections. This requires renaming all magic sections with names of the form ".text.foo". Signed-off-by: Tim Abbott <tabbott@mit.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-26 09:10:56 +07:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
#ifndef LOAD_OFFSET
#define LOAD_OFFSET 0
#endif
#ifndef VMLINUX_SYMBOL
#define VMLINUX_SYMBOL(_sym_) _sym_
#endif
kbuild: Avoid inconsistent kallsyms data Several reports on inconsistent kallsyms data has been caused by the aliased symbols __sched_text_start and __down to shift places in the output of nm. The root cause was that on second pass ld aligned __sched_text_start to a 4 byte boundary which is the function alignment on i386. sched.text and spinlock.text is now aligned to an 8 byte boundary to make sure they are aligned to a function alignemnt on most (all?) archs. Tested by: Paulo Marques <pmarques@grupopie.com> Tested by: Alexander Stohr <Alexander.Stohr@gmx.de> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-15 03:15:44 +07:00
/* Align . to a 8 byte boundary equals to maximum function alignment. */
#define ALIGN_FUNCTION() . = ALIGN(8)
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
/* The actual configuration determine if the init/exit sections
* are handled as text/data or they can be discarded (which
* often happens at runtime)
*/
#ifdef CONFIG_HOTPLUG
#define DEV_KEEP(sec) *(.dev##sec)
#define DEV_DISCARD(sec)
#else
#define DEV_KEEP(sec)
#define DEV_DISCARD(sec) *(.dev##sec)
#endif
#ifdef CONFIG_HOTPLUG_CPU
#define CPU_KEEP(sec) *(.cpu##sec)
#define CPU_DISCARD(sec)
#else
#define CPU_KEEP(sec)
#define CPU_DISCARD(sec) *(.cpu##sec)
#endif
asm-generic/vmlix.lds.h: simplify __mem{init,exit}* dependencies Simplify the dependencies on __mem{init,exit}* (ACPI_HOTPLUG_MEMORY requires MEMORY_HOTPLUG). Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-25 04:20:18 +07:00
#if defined(CONFIG_MEMORY_HOTPLUG)
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
#define MEM_KEEP(sec) *(.mem##sec)
#define MEM_DISCARD(sec)
#else
#define MEM_KEEP(sec)
#define MEM_DISCARD(sec) *(.mem##sec)
#endif
ftrace: create __mcount_loc section This patch creates a section in the kernel called "__mcount_loc". This will hold a list of pointers to the mcount relocation for each call site of mcount. For example: objdump -dr init/main.o [...] Disassembly of section .text: 0000000000000000 <do_one_initcall>: 0: 55 push %rbp [...] 000000000000017b <init_post>: 17b: 55 push %rbp 17c: 48 89 e5 mov %rsp,%rbp 17f: 53 push %rbx 180: 48 83 ec 08 sub $0x8,%rsp 184: e8 00 00 00 00 callq 189 <init_post+0xe> 185: R_X86_64_PC32 mcount+0xfffffffffffffffc [...] We will add a section to point to each function call. .section __mcount_loc,"a",@progbits [...] .quad .text + 0x185 [...] The offset to of the mcount call site in init_post is an offset from the start of the section, and not the start of the function init_post. The mcount relocation is at the call site 0x185 from the start of the .text section. .text + 0x185 == init_post + 0xa We need a way to add this __mcount_loc section in a way that we do not lose the relocations after final link. The .text section here will be attached to all other .text sections after final link and the offsets will be meaningless. We need to keep track of where these .text sections are. To do this, we use the start of the first function in the section. do_one_initcall. We can make a tmp.s file with this function as a reference to the start of the .text section. .section __mcount_loc,"a",@progbits [...] .quad do_one_initcall + 0x185 [...] Then we can compile the tmp.s into a tmp.o gcc -c tmp.s -o tmp.o And link it into back into main.o. ld -r main.o tmp.o -o tmp_main.o mv tmp_main.o main.o But we have a problem. What happens if the first function in a section is not exported, and is a static function. The linker will not let the tmp.o use it. This case exists in main.o as well. Disassembly of section .init.text: 0000000000000000 <set_reset_devices>: 0: 55 push %rbp 1: 48 89 e5 mov %rsp,%rbp 4: e8 00 00 00 00 callq 9 <set_reset_devices+0x9> 5: R_X86_64_PC32 mcount+0xfffffffffffffffc The first function in .init.text is a static function. 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices The lowercase 't' means that set_reset_devices is local and is not exported. If we simply try to link the tmp.o with the set_reset_devices we end up with two symbols: one local and one global. .section __mcount_loc,"a",@progbits .quad set_reset_devices + 0x10 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices U set_reset_devices We still have an undefined reference to set_reset_devices, and if we try to compile the kernel, we will end up with an undefined reference to set_reset_devices, or even worst, it could be exported someplace else, and then we will have a reference to the wrong location. To handle this case, we make an intermediate step using objcopy. We convert set_reset_devices into a global exported symbol before linking it with tmp.o and set it back afterwards. 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 T set_reset_devices 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 T set_reset_devices 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices Now we have a section in main.o called __mcount_loc that we can place somewhere in the kernel using vmlinux.ld.S and access it to convert all these locations that call mcount into nops before starting SMP and thus, eliminating the need to do this with kstop_machine. Note, A well documented perl script (scripts/recordmcount.pl) is used to do all this in one location. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 02:45:07 +07:00
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
#define MCOUNT_REC() VMLINUX_SYMBOL(__start_mcount_loc) = .; \
*(__mcount_loc) \
VMLINUX_SYMBOL(__stop_mcount_loc) = .;
#else
#define MCOUNT_REC()
#endif
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
trace: rename unlikely profiler to branch profiler Impact: name change of unlikely tracer and profiler Ingo Molnar suggested changing the config from UNLIKELY_PROFILE to BRANCH_PROFILING. I never did like the "unlikely" name so I went one step farther, and renamed all the unlikely configurations to a "BRANCH" variant. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-13 03:24:24 +07:00
#ifdef CONFIG_TRACE_BRANCH_PROFILING
trace: consolidate unlikely and likely profiler Impact: clean up to make one profiler of like and unlikely tracer The likely and unlikely profiler prints out the file and line numbers of the annotated branches that it is profiling. It shows the number of times it was correct or incorrect in its guess. Having two different files or sections for that matter to tell us if it was a likely or unlikely is pretty pointless. We really only care if it was correct or not. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-21 12:40:40 +07:00
#define LIKELY_PROFILE() VMLINUX_SYMBOL(__start_annotated_branch_profile) = .; \
*(_ftrace_annotated_branch) \
VMLINUX_SYMBOL(__stop_annotated_branch_profile) = .;
tracing: profile likely and unlikely annotations Impact: new unlikely/likely profiler Andrew Morton recently suggested having an in-kernel way to profile likely and unlikely macros. This patch achieves that goal. When configured, every(*) likely and unlikely macro gets a counter attached to it. When the condition is hit, the hit and misses of that condition are recorded. These numbers can later be retrieved by: /debugfs/tracing/profile_likely - All likely markers /debugfs/tracing/profile_unlikely - All unlikely markers. # cat /debug/tracing/profile_unlikely | head correct incorrect % Function File Line ------- --------- - -------- ---- ---- 2167 0 0 do_arch_prctl process_64.c 832 0 0 0 do_arch_prctl process_64.c 804 2670 0 0 IS_ERR err.h 34 71230 5693 7 __switch_to process_64.c 673 76919 0 0 __switch_to process_64.c 639 43184 33743 43 __switch_to process_64.c 624 12740 64181 83 __switch_to process_64.c 594 12740 64174 83 __switch_to process_64.c 590 # cat /debug/tracing/profile_unlikely | \ awk '{ if ($3 > 25) print $0; }' |head -20 44963 35259 43 __switch_to process_64.c 624 12762 67454 84 __switch_to process_64.c 594 12762 67447 84 __switch_to process_64.c 590 1478 595 28 syscall_get_error syscall.h 51 0 2821 100 syscall_trace_leave ptrace.c 1567 0 1 100 native_smp_prepare_cpus smpboot.c 1237 86338 265881 75 calc_delta_fair sched_fair.c 408 210410 108540 34 calc_delta_mine sched.c 1267 0 54550 100 sched_info_queued sched_stats.h 222 51899 66435 56 pick_next_task_fair sched_fair.c 1422 6 10 62 yield_task_fair sched_fair.c 982 7325 2692 26 rt_policy sched.c 144 0 1270 100 pre_schedule_rt sched_rt.c 1261 1268 48073 97 pick_next_task_rt sched_rt.c 884 0 45181 100 sched_info_dequeued sched_stats.h 177 0 15 100 sched_move_task sched.c 8700 0 15 100 sched_move_task sched.c 8690 53167 33217 38 schedule sched.c 4457 0 80208 100 sched_info_switch sched_stats.h 270 30585 49631 61 context_switch sched.c 2619 # cat /debug/tracing/profile_likely | awk '{ if ($3 > 25) print $0; }' 39900 36577 47 pick_next_task sched.c 4397 20824 15233 42 switch_mm mmu_context_64.h 18 0 7 100 __cancel_work_timer workqueue.c 560 617 66484 99 clocksource_adjust timekeeping.c 456 0 346340 100 audit_syscall_exit auditsc.c 1570 38 347350 99 audit_get_context auditsc.c 732 0 345244 100 audit_syscall_entry auditsc.c 1541 38 1017 96 audit_free auditsc.c 1446 0 1090 100 audit_alloc auditsc.c 862 2618 1090 29 audit_alloc auditsc.c 858 0 6 100 move_masked_irq migration.c 9 1 198 99 probe_sched_wakeup trace_sched_switch.c 58 2 2 50 probe_wakeup trace_sched_wakeup.c 227 0 2 100 probe_wakeup_sched_switch trace_sched_wakeup.c 144 4514 2090 31 __grab_cache_page filemap.c 2149 12882 228786 94 mapping_unevictable pagemap.h 50 4 11 73 __flush_cpu_slab slub.c 1466 627757 330451 34 slab_free slub.c 1731 2959 61245 95 dentry_lru_del_init dcache.c 153 946 1217 56 load_elf_binary binfmt_elf.c 904 102 82 44 disk_put_part genhd.h 206 1 1 50 dst_gc_task dst.c 82 0 19 100 tcp_mss_split_point tcp_output.c 1126 As you can see by the above, there's a bit of work to do in rethinking the use of some unlikelys and likelys. Note: the unlikely case had 71 hits that were more than 25%. Note: After submitting my first version of this patch, Andrew Morton showed me a version written by Daniel Walker, where I picked up the following ideas from: 1) Using __builtin_constant_p to avoid profiling fixed values. 2) Using __FILE__ instead of instruction pointers. 3) Using the preprocessor to stop all profiling of likely annotations from vsyscall_64.c. Thanks to Andrew Morton, Arjan van de Ven, Theodore Tso and Ingo Molnar for their feed back on this patch. (*) Not ever unlikely is recorded, those that are used by vsyscalls (a few of them) had to have profiling disabled. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Theodore Tso <tytso@mit.edu> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-12 12:14:39 +07:00
#else
#define LIKELY_PROFILE()
#endif
trace: profile all if conditionals Impact: feature to profile if statements This patch adds a branch profiler for all if () statements. The results will be found in: /debugfs/tracing/profile_branch For example: miss hit % Function File Line ------- --------- - -------- ---- ---- 0 1 100 x86_64_start_reservations head64.c 127 0 1 100 copy_bootdata head64.c 69 1 0 0 x86_64_start_kernel head64.c 111 32 0 0 set_intr_gate desc.h 319 1 0 0 reserve_ebda_region head.c 51 1 0 0 reserve_ebda_region head.c 47 0 1 100 reserve_ebda_region head.c 42 0 0 X maxcpus main.c 165 Miss means the branch was not taken. Hit means the branch was taken. The percent is the percentage the branch was taken. This adds a significant amount of overhead and should only be used by those analyzing their system. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-21 13:30:54 +07:00
#ifdef CONFIG_PROFILE_ALL_BRANCHES
#define BRANCH_PROFILE() VMLINUX_SYMBOL(__start_branch_profile) = .; \
*(_ftrace_branch) \
VMLINUX_SYMBOL(__stop_branch_profile) = .;
#else
#define BRANCH_PROFILE()
#endif
tracing: add event trace infrastructure This patch creates the event tracing infrastructure of ftrace. It will create the files: /debug/tracing/available_events /debug/tracing/set_event The available_events will list the trace points that have been registered with the event tracer. set_events will allow the user to enable or disable an event hook. example: # echo sched_wakeup > /debug/tracing/set_event Will enable the sched_wakeup event (if it is registered). # echo "!sched_wakeup" >> /debug/tracing/set_event Will disable the sched_wakeup event (and only that event). # echo > /debug/tracing/set_event Will disable all events (notice the '>') # cat /debug/tracing/available_events > /debug/tracing/set_event Will enable all registered event hooks. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
2009-02-24 22:21:36 +07:00
#ifdef CONFIG_EVENT_TRACER
#define FTRACE_EVENTS() VMLINUX_SYMBOL(__start_ftrace_events) = .; \
*(_ftrace_events) \
VMLINUX_SYMBOL(__stop_ftrace_events) = .;
#else
#define FTRACE_EVENTS()
#endif
tracing: add trace_bprintk() Impact: add a generic printk() for tracing, like trace_printk() trace_bprintk() uses the infrastructure to record events on ring_buffer. [ fweisbec@gmail.com: ported to latest -tip, made it work if !CONFIG_MODULES, never free the format strings from modules because we can't keep track of them and conditionnaly create the ftrace format strings section (reported by Steven Rostedt) ] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-4-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-06 23:21:48 +07:00
#ifdef CONFIG_TRACING
#define TRACE_PRINTKS() VMLINUX_SYMBOL(__start___trace_bprintk_fmt) = .; \
*(__trace_printk_fmt) /* Trace_printk fmt' pointer */ \
VMLINUX_SYMBOL(__stop___trace_bprintk_fmt) = .;
#else
#define TRACE_PRINTKS()
#endif
tracing/syscalls: core infrastructure for syscalls tracing, enhancements Impact: new feature This adds the generic support for syscalls tracing. This is currently exploited through a devoted tracer but other tracing engines can use it. (They just have to play with {start,stop}_ftrace_syscalls() and use the display callbacks unless they want to override them.) The syscalls prototypes definitions are abused here to steal some metadata informations: - syscall name, param types, param names, number of params The syscall addr is not directly saved during this definition because we don't know if its prototype is available in the namespace. But we don't really need it. The arch has just to build a function able to resolve the syscall number to its metadata struct. The current tracer prints the syscall names, parameters names and values (and their types optionally). Currently the value is a raw hex but higher level values diplaying is on my TODO list. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1236955332-10133-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 21:42:11 +07:00
#ifdef CONFIG_FTRACE_SYSCALLS
#define TRACE_SYSCALLS() VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \
*(__syscalls_metadata) \
VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
#else
#define TRACE_SYSCALLS()
#endif
all-archs: consolidate .data section definition in asm-generic With this consolidation we can now modify the .data section definition in one spot for all archs. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-17 18:38:44 +07:00
/* .data section */
#define DATA_DATA \
kbuild: introduce __init_refok/__initdata_refok to supress section mismatch warnings Throughout the kernel there are a few legitimite references to init or exit sections. Most of these are covered by the patterns included in modpost but a few nees special attention. To avoid hardcoding a lot of function names in modpost introduce a marker so relevant function/data can be marked. When modpost see a reference to a init/exit function from a function/data marked no warning will be issued. Idea from: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Andrew Morton <akpm@linux-foundation.org>
2007-05-18 01:14:48 +07:00
*(.data) \
Introduce new section reference annotations tags: __ref, __refdata, __refconst Today we have the following annotations for functions/data referencing __init/__exit functions / data: __init_refok => for init functions __initdata_refok => for init data __exit_refok => for exit functions There is really no difference between the __init and __exit versions and simplify it and to introduce a shorter annotation the following new annotations are introduced: __ref => for functions (code) that references __*init / __*exit __refdata => for variables __refconst => for const variables Whit this annotation is it more obvious what the annotation is for and there is no longer the arbitary division between __init and __exit code. The mechanishm is the same as before - a special section is created which is made part of the usual sections in the linker script. We will start to see annotations like this: -static struct pci_serial_quirk pci_serial_quirks[] = { +static const struct pci_serial_quirk pci_serial_quirks[] __refconst = { ----------------- -static struct notifier_block __cpuinitdata cpuid_class_cpu_notifier = +static struct notifier_block cpuid_class_cpu_notifier __refdata = ---------------- -static int threshold_cpu_callback(struct notifier_block *nfb, +static int __ref threshold_cpu_callback(struct notifier_block *nfb, [The above is just random samples]. Note: No modifications were needed in modpost to support the new sections due to the newly introduced blacklisting. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-29 02:21:15 +07:00
*(.ref.data) \
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
DEV_KEEP(init.data) \
DEV_KEEP(exit.data) \
CPU_KEEP(init.data) \
CPU_KEEP(exit.data) \
MEM_KEEP(init.data) \
MEM_KEEP(exit.data) \
Linux Kernel Markers The marker activation functions sits in kernel/marker.c. A hash table is used to keep track of the registered probes and armed markers, so the markers within a newly loaded module that should be active can be activated at module load time. marker_query has been removed. marker_get_first, marker_get_next and marker_release should be used as iterators on the markers. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: "Frank Ch. Eigler" <fche@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Mike Mason <mmlnx@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 13:41:06 +07:00
. = ALIGN(8); \
VMLINUX_SYMBOL(__start___markers) = .; \
*(__markers) \
tracing: Kernel Tracepoints Implementation of kernel tracepoints. Inspired from the Linux Kernel Markers. Allows complete typing verification by declaring both tracing statement inline functions and probe registration/unregistration static inline functions within the same macro "DEFINE_TRACE". No format string is required. See the tracepoint Documentation and Samples patches for usage examples. Taken from the documentation patch : "A tracepoint placed in code provides a hook to call a function (probe) that you can provide at runtime. A tracepoint can be "on" (a probe is connected to it) or "off" (no probe is attached). When a tracepoint is "off" it has no effect, except for adding a tiny time penalty (checking a condition for a branch) and space penalty (adding a few bytes for the function call at the end of the instrumented function and adds a data structure in a separate section). When a tracepoint is "on", the function you provide is called each time the tracepoint is executed, in the execution context of the caller. When the function provided ends its execution, it returns to the caller (continuing from the tracepoint site). You can put tracepoints at important locations in the code. They are lightweight hooks that can pass an arbitrary number of parameters, which prototypes are described in a tracepoint declaration placed in a header file." Addition and removal of tracepoints is synchronized by RCU using the scheduler (and preempt_disable) as guarantees to find a quiescent state (this is really RCU "classic"). The update side uses rcu_barrier_sched() with call_rcu_sched() and the read/execute side uses "preempt_disable()/preempt_enable()". We make sure the previous array containing probes, which has been scheduled for deletion by the rcu callback, is indeed freed before we proceed to the next update. It therefore limits the rate of modification of a single tracepoint to one update per RCU period. The objective here is to permit fast batch add/removal of probes on _different_ tracepoints. Changelog : - Use #name ":" #proto as string to identify the tracepoint in the tracepoint table. This will make sure not type mismatch happens due to connexion of a probe with the wrong type to a tracepoint declared with the same name in a different header. - Add tracepoint_entry_free_old. - Change __TO_TRACE to get rid of the 'i' iterator. Masami Hiramatsu <mhiramat@redhat.com> : Tested on x86-64. Performance impact of a tracepoint : same as markers, except that it adds about 70 bytes of instructions in an unlikely branch of each instrumented function (the for loop, the stack setup and the function call). It currently adds a memory read, a test and a conditional branch at the instrumentation site (in the hot path). Immediate values will eventually change this into a load immediate, test and branch, which removes the memory read which will make the i-cache impact smaller (changing the memory read for a load immediate removes 3-4 bytes per site on x86_32 (depending on mov prefixes), or 7-8 bytes on x86_64, it also saves the d-cache hit). About the performance impact of tracepoints (which is comparable to markers), even without immediate values optimizations, tests done by Hideo Aoki on ia64 show no regression. His test case was using hackbench on a kernel where scheduler instrumentation (about 5 events in code scheduler code) was added. Quoting Hideo Aoki about Markers : I evaluated overhead of kernel marker using linux-2.6-sched-fixes git tree, which includes several markers for LTTng, using an ia64 server. While the immediate trace mark feature isn't implemented on ia64, there is no major performance regression. So, I think that we don't have any issues to propose merging marker point patches into Linus's tree from the viewpoint of performance impact. I prepared two kernels to evaluate. The first one was compiled without CONFIG_MARKERS. The second one was enabled CONFIG_MARKERS. I downloaded the original hackbench from the following URL: http://devresources.linux-foundation.org/craiger/hackbench/src/hackbench.c I ran hackbench 5 times in each condition and calculated the average and difference between the kernels. The parameter of hackbench: every 50 from 50 to 800 The number of CPUs of the server: 2, 4, and 8 Below is the results. As you can see, major performance regression wasn't found in any case. Even if number of processes increases, differences between marker-enabled kernel and marker- disabled kernel doesn't increase. Moreover, if number of CPUs increases, the differences doesn't increase either. Curiously, marker-enabled kernel is better than marker-disabled kernel in more than half cases, although I guess it comes from the difference of memory access pattern. * 2 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 4.811 | 4.872 | +0.061 | +1.27 | 100 | 9.854 | 10.309 | +0.454 | +4.61 | 150 | 15.602 | 15.040 | -0.562 | -3.6 | 200 | 20.489 | 20.380 | -0.109 | -0.53 | 250 | 25.798 | 25.652 | -0.146 | -0.56 | 300 | 31.260 | 30.797 | -0.463 | -1.48 | 350 | 36.121 | 35.770 | -0.351 | -0.97 | 400 | 42.288 | 42.102 | -0.186 | -0.44 | 450 | 47.778 | 47.253 | -0.526 | -1.1 | 500 | 51.953 | 52.278 | +0.325 | +0.63 | 550 | 58.401 | 57.700 | -0.701 | -1.2 | 600 | 63.334 | 63.222 | -0.112 | -0.18 | 650 | 68.816 | 68.511 | -0.306 | -0.44 | 700 | 74.667 | 74.088 | -0.579 | -0.78 | 750 | 78.612 | 79.582 | +0.970 | +1.23 | 800 | 85.431 | 85.263 | -0.168 | -0.2 | -------------------------------------------------------------- * 4 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.586 | 2.584 | -0.003 | -0.1 | 100 | 5.254 | 5.283 | +0.030 | +0.56 | 150 | 8.012 | 8.074 | +0.061 | +0.76 | 200 | 11.172 | 11.000 | -0.172 | -1.54 | 250 | 13.917 | 14.036 | +0.119 | +0.86 | 300 | 16.905 | 16.543 | -0.362 | -2.14 | 350 | 19.901 | 20.036 | +0.135 | +0.68 | 400 | 22.908 | 23.094 | +0.186 | +0.81 | 450 | 26.273 | 26.101 | -0.172 | -0.66 | 500 | 29.554 | 29.092 | -0.461 | -1.56 | 550 | 32.377 | 32.274 | -0.103 | -0.32 | 600 | 35.855 | 35.322 | -0.533 | -1.49 | 650 | 39.192 | 38.388 | -0.804 | -2.05 | 700 | 41.744 | 41.719 | -0.025 | -0.06 | 750 | 45.016 | 44.496 | -0.520 | -1.16 | 800 | 48.212 | 47.603 | -0.609 | -1.26 | -------------------------------------------------------------- * 8 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.094 | 2.072 | -0.022 | -1.07 | 100 | 4.162 | 4.273 | +0.111 | +2.66 | 150 | 6.485 | 6.540 | +0.055 | +0.84 | 200 | 8.556 | 8.478 | -0.078 | -0.91 | 250 | 10.458 | 10.258 | -0.200 | -1.91 | 300 | 12.425 | 12.750 | +0.325 | +2.62 | 350 | 14.807 | 14.839 | +0.032 | +0.22 | 400 | 16.801 | 16.959 | +0.158 | +0.94 | 450 | 19.478 | 19.009 | -0.470 | -2.41 | 500 | 21.296 | 21.504 | +0.208 | +0.98 | 550 | 23.842 | 23.979 | +0.137 | +0.57 | 600 | 26.309 | 26.111 | -0.198 | -0.75 | 650 | 28.705 | 28.446 | -0.259 | -0.9 | 700 | 31.233 | 31.394 | +0.161 | +0.52 | 750 | 34.064 | 33.720 | -0.344 | -1.01 | 800 | 36.320 | 36.114 | -0.206 | -0.57 | -------------------------------------------------------------- Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: 'Peter Zijlstra' <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 23:16:16 +07:00
VMLINUX_SYMBOL(__stop___markers) = .; \
tracepoints: add DECLARE_TRACE() and DEFINE_TRACE() Impact: API *CHANGE*. Must update all tracepoint users. Add DEFINE_TRACE() to tracepoints to let them declare the tracepoint structure in a single spot for all the kernel. It helps reducing memory consumption, especially when declaring a lot of tracepoints, e.g. for kmalloc tracing. *API CHANGE WARNING*: now, DECLARE_TRACE() must be used in headers for tracepoint declarations rather than DEFINE_TRACE(). This is the sane way to do it. The name previously used was misleading. Updates scheduler instrumentation to follow this API change. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-15 05:47:47 +07:00
. = ALIGN(32); \
tracing: Kernel Tracepoints Implementation of kernel tracepoints. Inspired from the Linux Kernel Markers. Allows complete typing verification by declaring both tracing statement inline functions and probe registration/unregistration static inline functions within the same macro "DEFINE_TRACE". No format string is required. See the tracepoint Documentation and Samples patches for usage examples. Taken from the documentation patch : "A tracepoint placed in code provides a hook to call a function (probe) that you can provide at runtime. A tracepoint can be "on" (a probe is connected to it) or "off" (no probe is attached). When a tracepoint is "off" it has no effect, except for adding a tiny time penalty (checking a condition for a branch) and space penalty (adding a few bytes for the function call at the end of the instrumented function and adds a data structure in a separate section). When a tracepoint is "on", the function you provide is called each time the tracepoint is executed, in the execution context of the caller. When the function provided ends its execution, it returns to the caller (continuing from the tracepoint site). You can put tracepoints at important locations in the code. They are lightweight hooks that can pass an arbitrary number of parameters, which prototypes are described in a tracepoint declaration placed in a header file." Addition and removal of tracepoints is synchronized by RCU using the scheduler (and preempt_disable) as guarantees to find a quiescent state (this is really RCU "classic"). The update side uses rcu_barrier_sched() with call_rcu_sched() and the read/execute side uses "preempt_disable()/preempt_enable()". We make sure the previous array containing probes, which has been scheduled for deletion by the rcu callback, is indeed freed before we proceed to the next update. It therefore limits the rate of modification of a single tracepoint to one update per RCU period. The objective here is to permit fast batch add/removal of probes on _different_ tracepoints. Changelog : - Use #name ":" #proto as string to identify the tracepoint in the tracepoint table. This will make sure not type mismatch happens due to connexion of a probe with the wrong type to a tracepoint declared with the same name in a different header. - Add tracepoint_entry_free_old. - Change __TO_TRACE to get rid of the 'i' iterator. Masami Hiramatsu <mhiramat@redhat.com> : Tested on x86-64. Performance impact of a tracepoint : same as markers, except that it adds about 70 bytes of instructions in an unlikely branch of each instrumented function (the for loop, the stack setup and the function call). It currently adds a memory read, a test and a conditional branch at the instrumentation site (in the hot path). Immediate values will eventually change this into a load immediate, test and branch, which removes the memory read which will make the i-cache impact smaller (changing the memory read for a load immediate removes 3-4 bytes per site on x86_32 (depending on mov prefixes), or 7-8 bytes on x86_64, it also saves the d-cache hit). About the performance impact of tracepoints (which is comparable to markers), even without immediate values optimizations, tests done by Hideo Aoki on ia64 show no regression. His test case was using hackbench on a kernel where scheduler instrumentation (about 5 events in code scheduler code) was added. Quoting Hideo Aoki about Markers : I evaluated overhead of kernel marker using linux-2.6-sched-fixes git tree, which includes several markers for LTTng, using an ia64 server. While the immediate trace mark feature isn't implemented on ia64, there is no major performance regression. So, I think that we don't have any issues to propose merging marker point patches into Linus's tree from the viewpoint of performance impact. I prepared two kernels to evaluate. The first one was compiled without CONFIG_MARKERS. The second one was enabled CONFIG_MARKERS. I downloaded the original hackbench from the following URL: http://devresources.linux-foundation.org/craiger/hackbench/src/hackbench.c I ran hackbench 5 times in each condition and calculated the average and difference between the kernels. The parameter of hackbench: every 50 from 50 to 800 The number of CPUs of the server: 2, 4, and 8 Below is the results. As you can see, major performance regression wasn't found in any case. Even if number of processes increases, differences between marker-enabled kernel and marker- disabled kernel doesn't increase. Moreover, if number of CPUs increases, the differences doesn't increase either. Curiously, marker-enabled kernel is better than marker-disabled kernel in more than half cases, although I guess it comes from the difference of memory access pattern. * 2 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 4.811 | 4.872 | +0.061 | +1.27 | 100 | 9.854 | 10.309 | +0.454 | +4.61 | 150 | 15.602 | 15.040 | -0.562 | -3.6 | 200 | 20.489 | 20.380 | -0.109 | -0.53 | 250 | 25.798 | 25.652 | -0.146 | -0.56 | 300 | 31.260 | 30.797 | -0.463 | -1.48 | 350 | 36.121 | 35.770 | -0.351 | -0.97 | 400 | 42.288 | 42.102 | -0.186 | -0.44 | 450 | 47.778 | 47.253 | -0.526 | -1.1 | 500 | 51.953 | 52.278 | +0.325 | +0.63 | 550 | 58.401 | 57.700 | -0.701 | -1.2 | 600 | 63.334 | 63.222 | -0.112 | -0.18 | 650 | 68.816 | 68.511 | -0.306 | -0.44 | 700 | 74.667 | 74.088 | -0.579 | -0.78 | 750 | 78.612 | 79.582 | +0.970 | +1.23 | 800 | 85.431 | 85.263 | -0.168 | -0.2 | -------------------------------------------------------------- * 4 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.586 | 2.584 | -0.003 | -0.1 | 100 | 5.254 | 5.283 | +0.030 | +0.56 | 150 | 8.012 | 8.074 | +0.061 | +0.76 | 200 | 11.172 | 11.000 | -0.172 | -1.54 | 250 | 13.917 | 14.036 | +0.119 | +0.86 | 300 | 16.905 | 16.543 | -0.362 | -2.14 | 350 | 19.901 | 20.036 | +0.135 | +0.68 | 400 | 22.908 | 23.094 | +0.186 | +0.81 | 450 | 26.273 | 26.101 | -0.172 | -0.66 | 500 | 29.554 | 29.092 | -0.461 | -1.56 | 550 | 32.377 | 32.274 | -0.103 | -0.32 | 600 | 35.855 | 35.322 | -0.533 | -1.49 | 650 | 39.192 | 38.388 | -0.804 | -2.05 | 700 | 41.744 | 41.719 | -0.025 | -0.06 | 750 | 45.016 | 44.496 | -0.520 | -1.16 | 800 | 48.212 | 47.603 | -0.609 | -1.26 | -------------------------------------------------------------- * 8 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.094 | 2.072 | -0.022 | -1.07 | 100 | 4.162 | 4.273 | +0.111 | +2.66 | 150 | 6.485 | 6.540 | +0.055 | +0.84 | 200 | 8.556 | 8.478 | -0.078 | -0.91 | 250 | 10.458 | 10.258 | -0.200 | -1.91 | 300 | 12.425 | 12.750 | +0.325 | +2.62 | 350 | 14.807 | 14.839 | +0.032 | +0.22 | 400 | 16.801 | 16.959 | +0.158 | +0.94 | 450 | 19.478 | 19.009 | -0.470 | -2.41 | 500 | 21.296 | 21.504 | +0.208 | +0.98 | 550 | 23.842 | 23.979 | +0.137 | +0.57 | 600 | 26.309 | 26.111 | -0.198 | -0.75 | 650 | 28.705 | 28.446 | -0.259 | -0.9 | 700 | 31.233 | 31.394 | +0.161 | +0.52 | 750 | 34.064 | 33.720 | -0.344 | -1.01 | 800 | 36.320 | 36.114 | -0.206 | -0.57 | -------------------------------------------------------------- Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: 'Peter Zijlstra' <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 23:16:16 +07:00
VMLINUX_SYMBOL(__start___tracepoints) = .; \
*(__tracepoints) \
tracing: profile likely and unlikely annotations Impact: new unlikely/likely profiler Andrew Morton recently suggested having an in-kernel way to profile likely and unlikely macros. This patch achieves that goal. When configured, every(*) likely and unlikely macro gets a counter attached to it. When the condition is hit, the hit and misses of that condition are recorded. These numbers can later be retrieved by: /debugfs/tracing/profile_likely - All likely markers /debugfs/tracing/profile_unlikely - All unlikely markers. # cat /debug/tracing/profile_unlikely | head correct incorrect % Function File Line ------- --------- - -------- ---- ---- 2167 0 0 do_arch_prctl process_64.c 832 0 0 0 do_arch_prctl process_64.c 804 2670 0 0 IS_ERR err.h 34 71230 5693 7 __switch_to process_64.c 673 76919 0 0 __switch_to process_64.c 639 43184 33743 43 __switch_to process_64.c 624 12740 64181 83 __switch_to process_64.c 594 12740 64174 83 __switch_to process_64.c 590 # cat /debug/tracing/profile_unlikely | \ awk '{ if ($3 > 25) print $0; }' |head -20 44963 35259 43 __switch_to process_64.c 624 12762 67454 84 __switch_to process_64.c 594 12762 67447 84 __switch_to process_64.c 590 1478 595 28 syscall_get_error syscall.h 51 0 2821 100 syscall_trace_leave ptrace.c 1567 0 1 100 native_smp_prepare_cpus smpboot.c 1237 86338 265881 75 calc_delta_fair sched_fair.c 408 210410 108540 34 calc_delta_mine sched.c 1267 0 54550 100 sched_info_queued sched_stats.h 222 51899 66435 56 pick_next_task_fair sched_fair.c 1422 6 10 62 yield_task_fair sched_fair.c 982 7325 2692 26 rt_policy sched.c 144 0 1270 100 pre_schedule_rt sched_rt.c 1261 1268 48073 97 pick_next_task_rt sched_rt.c 884 0 45181 100 sched_info_dequeued sched_stats.h 177 0 15 100 sched_move_task sched.c 8700 0 15 100 sched_move_task sched.c 8690 53167 33217 38 schedule sched.c 4457 0 80208 100 sched_info_switch sched_stats.h 270 30585 49631 61 context_switch sched.c 2619 # cat /debug/tracing/profile_likely | awk '{ if ($3 > 25) print $0; }' 39900 36577 47 pick_next_task sched.c 4397 20824 15233 42 switch_mm mmu_context_64.h 18 0 7 100 __cancel_work_timer workqueue.c 560 617 66484 99 clocksource_adjust timekeeping.c 456 0 346340 100 audit_syscall_exit auditsc.c 1570 38 347350 99 audit_get_context auditsc.c 732 0 345244 100 audit_syscall_entry auditsc.c 1541 38 1017 96 audit_free auditsc.c 1446 0 1090 100 audit_alloc auditsc.c 862 2618 1090 29 audit_alloc auditsc.c 858 0 6 100 move_masked_irq migration.c 9 1 198 99 probe_sched_wakeup trace_sched_switch.c 58 2 2 50 probe_wakeup trace_sched_wakeup.c 227 0 2 100 probe_wakeup_sched_switch trace_sched_wakeup.c 144 4514 2090 31 __grab_cache_page filemap.c 2149 12882 228786 94 mapping_unevictable pagemap.h 50 4 11 73 __flush_cpu_slab slub.c 1466 627757 330451 34 slab_free slub.c 1731 2959 61245 95 dentry_lru_del_init dcache.c 153 946 1217 56 load_elf_binary binfmt_elf.c 904 102 82 44 disk_put_part genhd.h 206 1 1 50 dst_gc_task dst.c 82 0 19 100 tcp_mss_split_point tcp_output.c 1126 As you can see by the above, there's a bit of work to do in rethinking the use of some unlikelys and likelys. Note: the unlikely case had 71 hits that were more than 25%. Note: After submitting my first version of this patch, Andrew Morton showed me a version written by Daniel Walker, where I picked up the following ideas from: 1) Using __builtin_constant_p to avoid profiling fixed values. 2) Using __FILE__ instead of instruction pointers. 3) Using the preprocessor to stop all profiling of likely annotations from vsyscall_64.c. Thanks to Andrew Morton, Arjan van de Ven, Theodore Tso and Ingo Molnar for their feed back on this patch. (*) Not ever unlikely is recorded, those that are used by vsyscalls (a few of them) had to have profiling disabled. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Theodore Tso <tytso@mit.edu> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-12 12:14:39 +07:00
VMLINUX_SYMBOL(__stop___tracepoints) = .; \
dynamic debug: combine dprintk and dynamic printk This patch combines Greg Bank's dprintk() work with the existing dynamic printk patchset, we are now calling it 'dynamic debug'. The new feature of this patchset is a richer /debugfs control file interface, (an example output from my system is at the bottom), which allows fined grained control over the the debug output. The output can be controlled by function, file, module, format string, and line number. for example, enabled all debug messages in module 'nf_conntrack': echo -n 'module nf_conntrack +p' > /mnt/debugfs/dynamic_debug/control to disable them: echo -n 'module nf_conntrack -p' > /mnt/debugfs/dynamic_debug/control A further explanation can be found in the documentation patch. Signed-off-by: Greg Banks <gnb@sgi.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-02-05 23:51:38 +07:00
/* implement dynamic printk debug */ \
. = ALIGN(8); \
VMLINUX_SYMBOL(__start___verbose) = .; \
*(__verbose) \
VMLINUX_SYMBOL(__stop___verbose) = .; \
trace: profile all if conditionals Impact: feature to profile if statements This patch adds a branch profiler for all if () statements. The results will be found in: /debugfs/tracing/profile_branch For example: miss hit % Function File Line ------- --------- - -------- ---- ---- 0 1 100 x86_64_start_reservations head64.c 127 0 1 100 copy_bootdata head64.c 69 1 0 0 x86_64_start_kernel head64.c 111 32 0 0 set_intr_gate desc.h 319 1 0 0 reserve_ebda_region head.c 51 1 0 0 reserve_ebda_region head.c 47 0 1 100 reserve_ebda_region head.c 42 0 0 X maxcpus main.c 165 Miss means the branch was not taken. Hit means the branch was taken. The percent is the percentage the branch was taken. This adds a significant amount of overhead and should only be used by those analyzing their system. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-21 13:30:54 +07:00
LIKELY_PROFILE() \
tracing: add event trace infrastructure This patch creates the event tracing infrastructure of ftrace. It will create the files: /debug/tracing/available_events /debug/tracing/set_event The available_events will list the trace points that have been registered with the event tracer. set_events will allow the user to enable or disable an event hook. example: # echo sched_wakeup > /debug/tracing/set_event Will enable the sched_wakeup event (if it is registered). # echo "!sched_wakeup" >> /debug/tracing/set_event Will disable the sched_wakeup event (and only that event). # echo > /debug/tracing/set_event Will disable all events (notice the '>') # cat /debug/tracing/available_events > /debug/tracing/set_event Will enable all registered event hooks. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
2009-02-24 22:21:36 +07:00
BRANCH_PROFILE() \
tracing: trace_printk() fix, move format array to data section Impact: fix kernel crash when using trace_printk() trace_printk_fmt section is defined into the readonly section. But we do: trace_printk_fmt = fmt; to fill in that table of format strings - which is not read-only. Under CONFIG_DEBUG_RODATA=y this crashes ... Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1236356510-8381-5-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-09 16:09:06 +07:00
TRACE_PRINTKS() \
tracing/syscalls: core infrastructure for syscalls tracing, enhancements Impact: new feature This adds the generic support for syscalls tracing. This is currently exploited through a devoted tracer but other tracing engines can use it. (They just have to play with {start,stop}_ftrace_syscalls() and use the display callbacks unless they want to override them.) The syscalls prototypes definitions are abused here to steal some metadata informations: - syscall name, param types, param names, number of params The syscall addr is not directly saved during this definition because we don't know if its prototype is available in the namespace. But we don't really need it. The arch has just to build a function able to resolve the syscall number to its metadata struct. The current tracer prints the syscall names, parameters names and values (and their types optionally). Currently the value is a raw hex but higher level values diplaying is on my TODO list. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1236955332-10133-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 21:42:11 +07:00
FTRACE_EVENTS() \
TRACE_SYSCALLS()
all-archs: consolidate .data section definition in asm-generic With this consolidation we can now modify the .data section definition in one spot for all archs. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-17 18:38:44 +07:00
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
/*
* Data section helpers
*/
#define NOSAVE_DATA \
. = ALIGN(PAGE_SIZE); \
VMLINUX_SYMBOL(__nosave_begin) = .; \
*(.data.nosave) \
. = ALIGN(PAGE_SIZE); \
VMLINUX_SYMBOL(__nosave_end) = .;
#define PAGE_ALIGNED_DATA(page_align) \
. = ALIGN(page_align); \
*(.data.page_aligned)
#define READ_MOSTLY_DATA(align) \
. = ALIGN(align); \
*(.data.read_mostly)
#define CACHELINE_ALIGNED_DATA(align) \
. = ALIGN(align); \
*(.data.cacheline_aligned)
#define INIT_TASK(align) \
. = ALIGN(align); \
*(.data.init_task)
/*
* Read only Data
*/
#define RO_DATA_SECTION(align) \
sparc64: fix alignment bug in linker definition script The RO_DATA section were hardcoded to a specific alignment in include/asm-generic/vmlinux.h. But for sparc64 this did not match the PAGE_SIZE. Introduce a new section definition named: RO_DATA that takes actual alignment as parameter. RODATA are provided for backward compatibility. On top of this avoid hardcoding alignment for sparc64 in reset of the script Fix is build-tested on sparc64 + x86_64. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-30 02:29:00 +07:00
. = ALIGN((align)); \
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
.rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \
[PATCH] i386: Distinguish absolute symbols Ld knows about 2 kinds of symbols, absolute and section relative. Section relative symbols symbols change value when a section is moved and absolute symbols do not. Currently in the linker script we have several labels marking the beginning and ending of sections that are outside of sections, making them absolute symbols. Having a mixture of absolute and section relative symbols refereing to the same data is currently harmless but it is confusing. This must be done carefully as newer revs of ld do not place symbols that appear in sections without data and instead ld makes those symbols global :( My ultimate goal is to build a relocatable kernel. The safest and least intrusive technique is to generate relocation entries so the kernel can be relocated at load time. The only penalty would be an increase in the size of the kernel binary. The problem is that if absolute and relocatable symbols are not properly specified absolute symbols will be relocated or section relative symbols won't be, which is fatal. The practical motivation is that when generating kernels that will run from a reserved area for analyzing what caused a kernel panic, it is simpler if you don't need to hard code the physical memory location they will run at, especially for the distributions. [AK: and merged:] o Also put a message so that in future people can be aware of it and avoid introducing absolute symbols. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-12-07 08:14:03 +07:00
VMLINUX_SYMBOL(__start_rodata) = .; \
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
*(.rodata) *(.rodata.*) \
*(__vermagic) /* Kernel version magic */ \
Linux Kernel Markers The marker activation functions sits in kernel/marker.c. A hash table is used to keep track of the registered probes and armed markers, so the markers within a newly loaded module that should be active can be activated at module load time. marker_query has been removed. marker_get_first, marker_get_next and marker_release should be used as iterators on the markers. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: "Frank Ch. Eigler" <fche@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Mike Mason <mmlnx@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 13:41:06 +07:00
*(__markers_strings) /* Markers: strings */ \
tracing: Kernel Tracepoints Implementation of kernel tracepoints. Inspired from the Linux Kernel Markers. Allows complete typing verification by declaring both tracing statement inline functions and probe registration/unregistration static inline functions within the same macro "DEFINE_TRACE". No format string is required. See the tracepoint Documentation and Samples patches for usage examples. Taken from the documentation patch : "A tracepoint placed in code provides a hook to call a function (probe) that you can provide at runtime. A tracepoint can be "on" (a probe is connected to it) or "off" (no probe is attached). When a tracepoint is "off" it has no effect, except for adding a tiny time penalty (checking a condition for a branch) and space penalty (adding a few bytes for the function call at the end of the instrumented function and adds a data structure in a separate section). When a tracepoint is "on", the function you provide is called each time the tracepoint is executed, in the execution context of the caller. When the function provided ends its execution, it returns to the caller (continuing from the tracepoint site). You can put tracepoints at important locations in the code. They are lightweight hooks that can pass an arbitrary number of parameters, which prototypes are described in a tracepoint declaration placed in a header file." Addition and removal of tracepoints is synchronized by RCU using the scheduler (and preempt_disable) as guarantees to find a quiescent state (this is really RCU "classic"). The update side uses rcu_barrier_sched() with call_rcu_sched() and the read/execute side uses "preempt_disable()/preempt_enable()". We make sure the previous array containing probes, which has been scheduled for deletion by the rcu callback, is indeed freed before we proceed to the next update. It therefore limits the rate of modification of a single tracepoint to one update per RCU period. The objective here is to permit fast batch add/removal of probes on _different_ tracepoints. Changelog : - Use #name ":" #proto as string to identify the tracepoint in the tracepoint table. This will make sure not type mismatch happens due to connexion of a probe with the wrong type to a tracepoint declared with the same name in a different header. - Add tracepoint_entry_free_old. - Change __TO_TRACE to get rid of the 'i' iterator. Masami Hiramatsu <mhiramat@redhat.com> : Tested on x86-64. Performance impact of a tracepoint : same as markers, except that it adds about 70 bytes of instructions in an unlikely branch of each instrumented function (the for loop, the stack setup and the function call). It currently adds a memory read, a test and a conditional branch at the instrumentation site (in the hot path). Immediate values will eventually change this into a load immediate, test and branch, which removes the memory read which will make the i-cache impact smaller (changing the memory read for a load immediate removes 3-4 bytes per site on x86_32 (depending on mov prefixes), or 7-8 bytes on x86_64, it also saves the d-cache hit). About the performance impact of tracepoints (which is comparable to markers), even without immediate values optimizations, tests done by Hideo Aoki on ia64 show no regression. His test case was using hackbench on a kernel where scheduler instrumentation (about 5 events in code scheduler code) was added. Quoting Hideo Aoki about Markers : I evaluated overhead of kernel marker using linux-2.6-sched-fixes git tree, which includes several markers for LTTng, using an ia64 server. While the immediate trace mark feature isn't implemented on ia64, there is no major performance regression. So, I think that we don't have any issues to propose merging marker point patches into Linus's tree from the viewpoint of performance impact. I prepared two kernels to evaluate. The first one was compiled without CONFIG_MARKERS. The second one was enabled CONFIG_MARKERS. I downloaded the original hackbench from the following URL: http://devresources.linux-foundation.org/craiger/hackbench/src/hackbench.c I ran hackbench 5 times in each condition and calculated the average and difference between the kernels. The parameter of hackbench: every 50 from 50 to 800 The number of CPUs of the server: 2, 4, and 8 Below is the results. As you can see, major performance regression wasn't found in any case. Even if number of processes increases, differences between marker-enabled kernel and marker- disabled kernel doesn't increase. Moreover, if number of CPUs increases, the differences doesn't increase either. Curiously, marker-enabled kernel is better than marker-disabled kernel in more than half cases, although I guess it comes from the difference of memory access pattern. * 2 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 4.811 | 4.872 | +0.061 | +1.27 | 100 | 9.854 | 10.309 | +0.454 | +4.61 | 150 | 15.602 | 15.040 | -0.562 | -3.6 | 200 | 20.489 | 20.380 | -0.109 | -0.53 | 250 | 25.798 | 25.652 | -0.146 | -0.56 | 300 | 31.260 | 30.797 | -0.463 | -1.48 | 350 | 36.121 | 35.770 | -0.351 | -0.97 | 400 | 42.288 | 42.102 | -0.186 | -0.44 | 450 | 47.778 | 47.253 | -0.526 | -1.1 | 500 | 51.953 | 52.278 | +0.325 | +0.63 | 550 | 58.401 | 57.700 | -0.701 | -1.2 | 600 | 63.334 | 63.222 | -0.112 | -0.18 | 650 | 68.816 | 68.511 | -0.306 | -0.44 | 700 | 74.667 | 74.088 | -0.579 | -0.78 | 750 | 78.612 | 79.582 | +0.970 | +1.23 | 800 | 85.431 | 85.263 | -0.168 | -0.2 | -------------------------------------------------------------- * 4 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.586 | 2.584 | -0.003 | -0.1 | 100 | 5.254 | 5.283 | +0.030 | +0.56 | 150 | 8.012 | 8.074 | +0.061 | +0.76 | 200 | 11.172 | 11.000 | -0.172 | -1.54 | 250 | 13.917 | 14.036 | +0.119 | +0.86 | 300 | 16.905 | 16.543 | -0.362 | -2.14 | 350 | 19.901 | 20.036 | +0.135 | +0.68 | 400 | 22.908 | 23.094 | +0.186 | +0.81 | 450 | 26.273 | 26.101 | -0.172 | -0.66 | 500 | 29.554 | 29.092 | -0.461 | -1.56 | 550 | 32.377 | 32.274 | -0.103 | -0.32 | 600 | 35.855 | 35.322 | -0.533 | -1.49 | 650 | 39.192 | 38.388 | -0.804 | -2.05 | 700 | 41.744 | 41.719 | -0.025 | -0.06 | 750 | 45.016 | 44.496 | -0.520 | -1.16 | 800 | 48.212 | 47.603 | -0.609 | -1.26 | -------------------------------------------------------------- * 8 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.094 | 2.072 | -0.022 | -1.07 | 100 | 4.162 | 4.273 | +0.111 | +2.66 | 150 | 6.485 | 6.540 | +0.055 | +0.84 | 200 | 8.556 | 8.478 | -0.078 | -0.91 | 250 | 10.458 | 10.258 | -0.200 | -1.91 | 300 | 12.425 | 12.750 | +0.325 | +2.62 | 350 | 14.807 | 14.839 | +0.032 | +0.22 | 400 | 16.801 | 16.959 | +0.158 | +0.94 | 450 | 19.478 | 19.009 | -0.470 | -2.41 | 500 | 21.296 | 21.504 | +0.208 | +0.98 | 550 | 23.842 | 23.979 | +0.137 | +0.57 | 600 | 26.309 | 26.111 | -0.198 | -0.75 | 650 | 28.705 | 28.446 | -0.259 | -0.9 | 700 | 31.233 | 31.394 | +0.161 | +0.52 | 750 | 34.064 | 33.720 | -0.344 | -1.01 | 800 | 36.320 | 36.114 | -0.206 | -0.57 | -------------------------------------------------------------- Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: 'Peter Zijlstra' <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 23:16:16 +07:00
*(__tracepoints_strings)/* Tracepoints: strings */ \
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
} \
\
.rodata1 : AT(ADDR(.rodata1) - LOAD_OFFSET) { \
*(.rodata1) \
} \
\
move BUG_TABLE into RODATA Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:41 +07:00
BUG_TABLE \
\
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
/* PCI quirks */ \
.pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start_pci_fixups_early) = .; \
*(.pci_fixup_early) \
VMLINUX_SYMBOL(__end_pci_fixups_early) = .; \
VMLINUX_SYMBOL(__start_pci_fixups_header) = .; \
*(.pci_fixup_header) \
VMLINUX_SYMBOL(__end_pci_fixups_header) = .; \
VMLINUX_SYMBOL(__start_pci_fixups_final) = .; \
*(.pci_fixup_final) \
VMLINUX_SYMBOL(__end_pci_fixups_final) = .; \
VMLINUX_SYMBOL(__start_pci_fixups_enable) = .; \
*(.pci_fixup_enable) \
VMLINUX_SYMBOL(__end_pci_fixups_enable) = .; \
PCI: Fix multiple problems with VIA hardware This patch is designed to fix: - Disk eating corruptor on KT7 after resume from RAM - VIA IRQ handling - VIA fixups for bus lockups after resume from RAM The core of this is to add a table of resume fixups run at resume time. We need to do this for a variety of boards and features, but particularly we need to do this to get various critical VIA fixups done on resume. The second part of the problem is to handle VIA IRQ number rules which are a bit odd and need special handling for PIC interrupts. Various patches broke various boxes and while this one may not be perfect (hopefully it is) it ensures the workaround is applied to the right devices only. From: Jean Delvare <khali@linux-fr.org> Now that PCI quirks are replayed on software resume, we can safely re-enable the Asus SMBus unhiding quirk even when software suspend support is enabled. [akpm@osdl.org: fix const warning] Signed-off-by: Alan Cox <alan@redhat.com> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-05 06:14:45 +07:00
VMLINUX_SYMBOL(__start_pci_fixups_resume) = .; \
*(.pci_fixup_resume) \
VMLINUX_SYMBOL(__end_pci_fixups_resume) = .; \
Suspend/Resume bug in PCI layer wrt quirks Some quirks should be called with interrupt disabled, we can't directly call them in .resume_early. Also the patch introduces pci_fixup_resume_early and pci_fixup_suspend, which matches current device core callbacks (.suspend/.resume_early). TBD: Somebody knows why we need quirk resume should double check if a quirk should be called in resume or resume_early. I changed some per my understanding, but can't make sure I fixed all. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-05-16 02:51:31 +07:00
VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .; \
*(.pci_fixup_resume_early) \
VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .; \
VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .; \
*(.pci_fixup_suspend) \
VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .; \
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
} \
\
firmware: allow firmware files to be built into kernel image Some drivers have their own hacks to bypass the kernel's firmware loader and build their firmware into the kernel; this renders those unnecessary. Other drivers don't use the firmware loader at all, because they always want the firmware to be available. This allows them to start using the firmware loader. A third set of drivers already use the firmware loader, but can't be used without help from userspace, which sometimes requires an initrd. This allows them to work in a static kernel. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2008-05-23 19:52:42 +07:00
/* Built-in firmware blobs */ \
.builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start_builtin_fw) = .; \
*(.builtin_fw) \
VMLINUX_SYMBOL(__end_builtin_fw) = .; \
} \
\
[PATCH] RapidIO support: core base Adds a RapidIO subsystem to the kernel. RIO is a switched fabric interconnect used in higher-end embedded applications. The curious can look at the specs over at http://www.rapidio.org The core code implements enumeration/discovery, management of devices/resources, and interfaces for RIO drivers. There's a lot more to do to take advantages of all the hardware features. However, this should provide a good base for folks with RIO hardware to start contributing. Signed-off-by: Matt Porter <mporter@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 16:00:15 +07:00
/* RapidIO route ops */ \
.rio_route : AT(ADDR(.rio_route) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start_rio_route_ops) = .; \
*(.rio_route_ops) \
VMLINUX_SYMBOL(__end_rio_route_ops) = .; \
} \
\
x86: move tracedata to RODATA .. allowing it to be write-protected just as other read-only data under CONFIG_DEBUG_RODATA. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:41 +07:00
TRACEDATA \
\
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
/* Kernel symbol table: Normal symbols */ \
__ksymtab : AT(ADDR(__ksymtab) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ksymtab) = .; \
*(__ksymtab) \
VMLINUX_SYMBOL(__stop___ksymtab) = .; \
} \
\
/* Kernel symbol table: GPL-only symbols */ \
__ksymtab_gpl : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ksymtab_gpl) = .; \
*(__ksymtab_gpl) \
VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .; \
} \
\
[PATCH] Add EXPORT_UNUSED_SYMBOL and EXPORT_UNUSED_SYMBOL_GPL Temporarily add EXPORT_UNUSED_SYMBOL and EXPORT_UNUSED_SYMBOL_GPL. These will be used as a transition measure for symbols that aren't used in the kernel and are on the way out. When a module uses such a symbol, a warning is printk'd at modprobe time. The main reason for removing unused exports is size: eacho export takes roughly between 100 and 150 bytes of kernel space in the binary. This patch gives users the option to immediately get this size gain via a config option. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28 18:26:45 +07:00
/* Kernel symbol table: Normal unused symbols */ \
__ksymtab_unused : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ksymtab_unused) = .; \
*(__ksymtab_unused) \
VMLINUX_SYMBOL(__stop___ksymtab_unused) = .; \
} \
\
/* Kernel symbol table: GPL-only unused symbols */ \
__ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ksymtab_unused_gpl) = .; \
*(__ksymtab_unused_gpl) \
VMLINUX_SYMBOL(__stop___ksymtab_unused_gpl) = .; \
} \
\
[PATCH] add EXPORT_SYMBOL_GPL_FUTURE() This patch adds the ability to mark symbols that will be changed in the future, so that kernel modules that don't include MODULE_LICENSE("GPL") and use the symbols, will be flagged and printed out to the system log. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-21 04:17:13 +07:00
/* Kernel symbol table: GPL-future-only symbols */ \
__ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ksymtab_gpl_future) = .; \
*(__ksymtab_gpl_future) \
VMLINUX_SYMBOL(__stop___ksymtab_gpl_future) = .; \
} \
\
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
/* Kernel symbol table: Normal symbols */ \
__kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___kcrctab) = .; \
*(__kcrctab) \
VMLINUX_SYMBOL(__stop___kcrctab) = .; \
} \
\
/* Kernel symbol table: GPL-only symbols */ \
__kcrctab_gpl : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___kcrctab_gpl) = .; \
*(__kcrctab_gpl) \
VMLINUX_SYMBOL(__stop___kcrctab_gpl) = .; \
} \
\
[PATCH] Add EXPORT_UNUSED_SYMBOL and EXPORT_UNUSED_SYMBOL_GPL Temporarily add EXPORT_UNUSED_SYMBOL and EXPORT_UNUSED_SYMBOL_GPL. These will be used as a transition measure for symbols that aren't used in the kernel and are on the way out. When a module uses such a symbol, a warning is printk'd at modprobe time. The main reason for removing unused exports is size: eacho export takes roughly between 100 and 150 bytes of kernel space in the binary. This patch gives users the option to immediately get this size gain via a config option. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28 18:26:45 +07:00
/* Kernel symbol table: Normal unused symbols */ \
__kcrctab_unused : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___kcrctab_unused) = .; \
*(__kcrctab_unused) \
VMLINUX_SYMBOL(__stop___kcrctab_unused) = .; \
} \
\
/* Kernel symbol table: GPL-only unused symbols */ \
__kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___kcrctab_unused_gpl) = .; \
*(__kcrctab_unused_gpl) \
VMLINUX_SYMBOL(__stop___kcrctab_unused_gpl) = .; \
} \
\
[PATCH] add EXPORT_SYMBOL_GPL_FUTURE() This patch adds the ability to mark symbols that will be changed in the future, so that kernel modules that don't include MODULE_LICENSE("GPL") and use the symbols, will be flagged and printed out to the system log. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-21 04:17:13 +07:00
/* Kernel symbol table: GPL-future-only symbols */ \
__kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___kcrctab_gpl_future) = .; \
*(__kcrctab_gpl_future) \
VMLINUX_SYMBOL(__stop___kcrctab_gpl_future) = .; \
} \
\
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
/* Kernel symbol table: strings */ \
__ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
*(__ksymtab_strings) \
} \
\
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
/* __*init sections */ \
__init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \
Introduce new section reference annotations tags: __ref, __refdata, __refconst Today we have the following annotations for functions/data referencing __init/__exit functions / data: __init_refok => for init functions __initdata_refok => for init data __exit_refok => for exit functions There is really no difference between the __init and __exit versions and simplify it and to introduce a shorter annotation the following new annotations are introduced: __ref => for functions (code) that references __*init / __*exit __refdata => for variables __refconst => for const variables Whit this annotation is it more obvious what the annotation is for and there is no longer the arbitary division between __init and __exit code. The mechanishm is the same as before - a special section is created which is made part of the usual sections in the linker script. We will start to see annotations like this: -static struct pci_serial_quirk pci_serial_quirks[] = { +static const struct pci_serial_quirk pci_serial_quirks[] __refconst = { ----------------- -static struct notifier_block __cpuinitdata cpuid_class_cpu_notifier = +static struct notifier_block cpuid_class_cpu_notifier __refdata = ---------------- -static int threshold_cpu_callback(struct notifier_block *nfb, +static int __ref threshold_cpu_callback(struct notifier_block *nfb, [The above is just random samples]. Note: No modifications were needed in modpost to support the new sections due to the newly introduced blacklisting. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-29 02:21:15 +07:00
*(.ref.rodata) \
ftrace: create __mcount_loc section This patch creates a section in the kernel called "__mcount_loc". This will hold a list of pointers to the mcount relocation for each call site of mcount. For example: objdump -dr init/main.o [...] Disassembly of section .text: 0000000000000000 <do_one_initcall>: 0: 55 push %rbp [...] 000000000000017b <init_post>: 17b: 55 push %rbp 17c: 48 89 e5 mov %rsp,%rbp 17f: 53 push %rbx 180: 48 83 ec 08 sub $0x8,%rsp 184: e8 00 00 00 00 callq 189 <init_post+0xe> 185: R_X86_64_PC32 mcount+0xfffffffffffffffc [...] We will add a section to point to each function call. .section __mcount_loc,"a",@progbits [...] .quad .text + 0x185 [...] The offset to of the mcount call site in init_post is an offset from the start of the section, and not the start of the function init_post. The mcount relocation is at the call site 0x185 from the start of the .text section. .text + 0x185 == init_post + 0xa We need a way to add this __mcount_loc section in a way that we do not lose the relocations after final link. The .text section here will be attached to all other .text sections after final link and the offsets will be meaningless. We need to keep track of where these .text sections are. To do this, we use the start of the first function in the section. do_one_initcall. We can make a tmp.s file with this function as a reference to the start of the .text section. .section __mcount_loc,"a",@progbits [...] .quad do_one_initcall + 0x185 [...] Then we can compile the tmp.s into a tmp.o gcc -c tmp.s -o tmp.o And link it into back into main.o. ld -r main.o tmp.o -o tmp_main.o mv tmp_main.o main.o But we have a problem. What happens if the first function in a section is not exported, and is a static function. The linker will not let the tmp.o use it. This case exists in main.o as well. Disassembly of section .init.text: 0000000000000000 <set_reset_devices>: 0: 55 push %rbp 1: 48 89 e5 mov %rsp,%rbp 4: e8 00 00 00 00 callq 9 <set_reset_devices+0x9> 5: R_X86_64_PC32 mcount+0xfffffffffffffffc The first function in .init.text is a static function. 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices The lowercase 't' means that set_reset_devices is local and is not exported. If we simply try to link the tmp.o with the set_reset_devices we end up with two symbols: one local and one global. .section __mcount_loc,"a",@progbits .quad set_reset_devices + 0x10 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices U set_reset_devices We still have an undefined reference to set_reset_devices, and if we try to compile the kernel, we will end up with an undefined reference to set_reset_devices, or even worst, it could be exported someplace else, and then we will have a reference to the wrong location. To handle this case, we make an intermediate step using objcopy. We convert set_reset_devices into a global exported symbol before linking it with tmp.o and set it back afterwards. 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 T set_reset_devices 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 T set_reset_devices 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices Now we have a section in main.o called __mcount_loc that we can place somewhere in the kernel using vmlinux.ld.S and access it to convert all these locations that call mcount into nops before starting SMP and thus, eliminating the need to do this with kstop_machine. Note, A well documented perl script (scripts/recordmcount.pl) is used to do all this in one location. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15 02:45:07 +07:00
MCOUNT_REC() \
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
DEV_KEEP(init.rodata) \
DEV_KEEP(exit.rodata) \
CPU_KEEP(init.rodata) \
CPU_KEEP(exit.rodata) \
MEM_KEEP(init.rodata) \
MEM_KEEP(exit.rodata) \
} \
\
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
/* Built-in module parameters. */ \
__param : AT(ADDR(__param) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___param) = .; \
*(__param) \
VMLINUX_SYMBOL(__stop___param) = .; \
x86: add testcases for RODATA and NX protections/attributes Latest update; I now have 4 NX tests, but 2 fail so they're #if 0'd. I also cleaned up the NX test code quite a bit, and got rid of the ugly exception table sorting stuff. From: Arjan van de Ven <arjan@linux.intel.com> This patch adds testcases for the CONFIG_DEBUG_RODATA configuration option as well as the NX CPU feature/mappings. Both testcases can move to tests/ once that patch gets merged into mainline. (I'm half considering moving the rodata test into mm/init.c but I'll wait with that until init.c is unified) As part of this I had to fix a not-quite-right alignment in the vmlinux.lds.h for the RODATA sections, which lead to 1 page less being marked read only. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 19:34:08 +07:00
. = ALIGN((align)); \
[PATCH] i386: Distinguish absolute symbols Ld knows about 2 kinds of symbols, absolute and section relative. Section relative symbols symbols change value when a section is moved and absolute symbols do not. Currently in the linker script we have several labels marking the beginning and ending of sections that are outside of sections, making them absolute symbols. Having a mixture of absolute and section relative symbols refereing to the same data is currently harmless but it is confusing. This must be done carefully as newer revs of ld do not place symbols that appear in sections without data and instead ld makes those symbols global :( My ultimate goal is to build a relocatable kernel. The safest and least intrusive technique is to generate relocation entries so the kernel can be relocated at load time. The only penalty would be an increase in the size of the kernel binary. The problem is that if absolute and relocatable symbols are not properly specified absolute symbols will be relocated or section relative symbols won't be, which is fatal. The practical motivation is that when generating kernels that will run from a reserved area for analyzing what caused a kernel panic, it is simpler if you don't need to hard code the physical memory location they will run at, especially for the distributions. [AK: and merged:] o Also put a message so that in future people can be aware of it and avoid introducing absolute symbols. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-12-07 08:14:03 +07:00
VMLINUX_SYMBOL(__end_rodata) = .; \
[PATCH] Include __param section in read-only data range The param section is an array of "kernel_param" structures, storing only constant data: pointer to name, permission of the variable pointed to by (void *)arg and pointers to set/get methods. Move end_rodata down to include __param section in the read-only range used by CONFIG_DEBUG_RODATA. Signed-off-by: Marcelo Tosatti <marcelo@kvack.org> Acked-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 15:51:02 +07:00
} \
sparc64: fix alignment bug in linker definition script The RO_DATA section were hardcoded to a specific alignment in include/asm-generic/vmlinux.h. But for sparc64 this did not match the PAGE_SIZE. Introduce a new section definition named: RO_DATA that takes actual alignment as parameter. RODATA are provided for backward compatibility. On top of this avoid hardcoding alignment for sparc64 in reset of the script Fix is build-tested on sparc64 + x86_64. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-30 02:29:00 +07:00
. = ALIGN((align));
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
/* RODATA & RO_DATA provided for backward compatibility.
sparc64: fix alignment bug in linker definition script The RO_DATA section were hardcoded to a specific alignment in include/asm-generic/vmlinux.h. But for sparc64 this did not match the PAGE_SIZE. Introduce a new section definition named: RO_DATA that takes actual alignment as parameter. RODATA are provided for backward compatibility. On top of this avoid hardcoding alignment for sparc64 in reset of the script Fix is build-tested on sparc64 + x86_64. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-30 02:29:00 +07:00
* All archs are supposed to use RO_DATA() */
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
#define RODATA RO_DATA_SECTION(4096)
#define RO_DATA(align) RO_DATA_SECTION(align)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
#define SECURITY_INIT \
[PATCH] kexec: vmlinux: fix physical addresses In vmlinux.lds.h the code is carefull to define every section so vmlinux properly reports the correct physical load address of code, as well as it's virtual address. The new SECURITY_INIT definition fails to follow that convention and and causes incorrect physical address to appear in the vmlinux if there are any security initcalls. This patch updates the SECURITY_INIT to follow the convention in the rest of the file. Signed-off-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-26 04:57:46 +07:00
.security_initcall.init : AT(ADDR(.security_initcall.init) - LOAD_OFFSET) { \
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
VMLINUX_SYMBOL(__security_initcall_start) = .; \
*(.security_initcall.init) \
VMLINUX_SYMBOL(__security_initcall_end) = .; \
}
all-archs: consolidate .text section definition in asm-generic Move definition of .text section to asm-generic. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-13 05:31:33 +07:00
/* .text section. Map to function alignment to avoid address changes
* during second ld run in second ld pass when generating System.map */
#define TEXT_TEXT \
ALIGN_FUNCTION(); \
vmlinux.lds: move __attribute__((__cold__)) functions back into final .text section Due to the addition of __attribute__((__cold__)) to a few symbols without adjusting the linker scripts, those symbols currently may end up outside the [_stext,_etext) range, as they get placed in .text.unlikely by (at least) gcc 4.3.0. This may confuse code not only outside of the kernel, symbol_put_addr()'s BUG() could also trigger. Hence we need to add .text.unlikely (and for future uses of __attribute__((__hot__)) also .text.hot) to the TEXT_TEXT() macro. Issue observed by Lukas Lipavsky. Signed-off-by: Jan Beulich <jbeulich@novell.com> Tested-by: Lukas Lipavsky <llipavsky@suse.cz> Cc: <stable@kernel.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-06-18 18:36:01 +07:00
*(.text.hot) \
kbuild: introduce __init_refok/__initdata_refok to supress section mismatch warnings Throughout the kernel there are a few legitimite references to init or exit sections. Most of these are covered by the patterns included in modpost but a few nees special attention. To avoid hardcoding a lot of function names in modpost introduce a marker so relevant function/data can be marked. When modpost see a reference to a init/exit function from a function/data marked no warning will be issued. Idea from: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Andrew Morton <akpm@linux-foundation.org>
2007-05-18 01:14:48 +07:00
*(.text) \
Introduce new section reference annotations tags: __ref, __refdata, __refconst Today we have the following annotations for functions/data referencing __init/__exit functions / data: __init_refok => for init functions __initdata_refok => for init data __exit_refok => for exit functions There is really no difference between the __init and __exit versions and simplify it and to introduce a shorter annotation the following new annotations are introduced: __ref => for functions (code) that references __*init / __*exit __refdata => for variables __refconst => for const variables Whit this annotation is it more obvious what the annotation is for and there is no longer the arbitary division between __init and __exit code. The mechanishm is the same as before - a special section is created which is made part of the usual sections in the linker script. We will start to see annotations like this: -static struct pci_serial_quirk pci_serial_quirks[] = { +static const struct pci_serial_quirk pci_serial_quirks[] __refconst = { ----------------- -static struct notifier_block __cpuinitdata cpuid_class_cpu_notifier = +static struct notifier_block cpuid_class_cpu_notifier __refdata = ---------------- -static int threshold_cpu_callback(struct notifier_block *nfb, +static int __ref threshold_cpu_callback(struct notifier_block *nfb, [The above is just random samples]. Note: No modifications were needed in modpost to support the new sections due to the newly introduced blacklisting. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-29 02:21:15 +07:00
*(.ref.text) \
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
DEV_KEEP(init.text) \
DEV_KEEP(exit.text) \
CPU_KEEP(init.text) \
CPU_KEEP(exit.text) \
MEM_KEEP(init.text) \
vmlinux.lds: move __attribute__((__cold__)) functions back into final .text section Due to the addition of __attribute__((__cold__)) to a few symbols without adjusting the linker scripts, those symbols currently may end up outside the [_stext,_etext) range, as they get placed in .text.unlikely by (at least) gcc 4.3.0. This may confuse code not only outside of the kernel, symbol_put_addr()'s BUG() could also trigger. Hence we need to add .text.unlikely (and for future uses of __attribute__((__hot__)) also .text.hot) to the TEXT_TEXT() macro. Issue observed by Lukas Lipavsky. Signed-off-by: Jan Beulich <jbeulich@novell.com> Tested-by: Lukas Lipavsky <llipavsky@suse.cz> Cc: <stable@kernel.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-06-18 18:36:01 +07:00
MEM_KEEP(exit.text) \
*(.text.unlikely)
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
all-archs: consolidate .text section definition in asm-generic Move definition of .text section to asm-generic. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-13 05:31:33 +07:00
kbuild: Avoid inconsistent kallsyms data Several reports on inconsistent kallsyms data has been caused by the aliased symbols __sched_text_start and __down to shift places in the output of nm. The root cause was that on second pass ld aligned __sched_text_start to a 4 byte boundary which is the function alignment on i386. sched.text and spinlock.text is now aligned to an 8 byte boundary to make sure they are aligned to a function alignemnt on most (all?) archs. Tested by: Paulo Marques <pmarques@grupopie.com> Tested by: Alexander Stohr <Alexander.Stohr@gmx.de> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-15 03:15:44 +07:00
/* sched.text is aling to function alignment to secure we have same
* address even at second ld pass when generating System.map */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
#define SCHED_TEXT \
kbuild: Avoid inconsistent kallsyms data Several reports on inconsistent kallsyms data has been caused by the aliased symbols __sched_text_start and __down to shift places in the output of nm. The root cause was that on second pass ld aligned __sched_text_start to a 4 byte boundary which is the function alignment on i386. sched.text and spinlock.text is now aligned to an 8 byte boundary to make sure they are aligned to a function alignemnt on most (all?) archs. Tested by: Paulo Marques <pmarques@grupopie.com> Tested by: Alexander Stohr <Alexander.Stohr@gmx.de> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-15 03:15:44 +07:00
ALIGN_FUNCTION(); \
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
VMLINUX_SYMBOL(__sched_text_start) = .; \
*(.sched.text) \
VMLINUX_SYMBOL(__sched_text_end) = .;
kbuild: Avoid inconsistent kallsyms data Several reports on inconsistent kallsyms data has been caused by the aliased symbols __sched_text_start and __down to shift places in the output of nm. The root cause was that on second pass ld aligned __sched_text_start to a 4 byte boundary which is the function alignment on i386. sched.text and spinlock.text is now aligned to an 8 byte boundary to make sure they are aligned to a function alignemnt on most (all?) archs. Tested by: Paulo Marques <pmarques@grupopie.com> Tested by: Alexander Stohr <Alexander.Stohr@gmx.de> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-15 03:15:44 +07:00
/* spinlock.text is aling to function alignment to secure we have same
* address even at second ld pass when generating System.map */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
#define LOCK_TEXT \
kbuild: Avoid inconsistent kallsyms data Several reports on inconsistent kallsyms data has been caused by the aliased symbols __sched_text_start and __down to shift places in the output of nm. The root cause was that on second pass ld aligned __sched_text_start to a 4 byte boundary which is the function alignment on i386. sched.text and spinlock.text is now aligned to an 8 byte boundary to make sure they are aligned to a function alignemnt on most (all?) archs. Tested by: Paulo Marques <pmarques@grupopie.com> Tested by: Alexander Stohr <Alexander.Stohr@gmx.de> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-15 03:15:44 +07:00
ALIGN_FUNCTION(); \
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 05:20:36 +07:00
VMLINUX_SYMBOL(__lock_text_start) = .; \
*(.spinlock.text) \
VMLINUX_SYMBOL(__lock_text_end) = .;
[PATCH] Kprobes: prevent possible race conditions generic There are possible race conditions if probes are placed on routines within the kprobes files and routines used by the kprobes. For example if you put probe on get_kprobe() routines, the system can hang while inserting probes on any routine such as do_fork(). Because while inserting probes on do_fork(), register_kprobes() routine grabs the kprobes spin lock and executes get_kprobe() routine and to handle probe of get_kprobe(), kprobes_handler() gets executed and tries to grab kprobes spin lock, and spins forever. This patch avoids such possible race conditions by preventing probes on routines within the kprobes file and routines used by kprobes. I have modified the patches as per Andi Kleen's suggestion to move kprobes routines and other routines used by kprobes to a seperate section .kprobes.text. Also moved page fault and exception handlers, general protection fault to .kprobes.text section. These patches have been tested on i386, x86_64 and ppc64 architectures, also compiled on ia64 and sparc64 architectures. Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 05:19:26 +07:00
#define KPROBES_TEXT \
ALIGN_FUNCTION(); \
VMLINUX_SYMBOL(__kprobes_text_start) = .; \
*(.kprobes.text) \
VMLINUX_SYMBOL(__kprobes_text_end) = .;
[PATCH] i386 / uml: add dwarf sections to static link script Inside the linker script, insert the code for DWARF debug info sections. This may help GDB'ing a Uml binary. Actually, it seems that ld is able to guess what I added correctly, but normal linker scripts include this section so it should be correct anyway adding it. On request by Sam Ravnborg <sam@ravnborg.org>, I've added it to asm-generic/vmlinux.lds.s. I've also moved there the stabs debug section, used the new macro in i386 linker script and added DWARF debug section to that. In the truth, I've not been able to verify the difference in GDB behaviour after this change (I've seen large improvements with another patch). This may depend on my binutils version, older one may have worse defaults. However, this section is present in normal linker script, so add it at least for the sake of cleanness. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-11 00:44:54 +07:00
tracing/function-graph-tracer: add a new .irqentry.text section Impact: let the function-graph-tracer be aware of the irq entrypoints Add a new .irqentry.text section to store the irq entrypoints functions inside the same section. This way, the tracer will be able to signal an interrupts triggering on output by recognizing these entrypoints. Also, make this section recordable for dynamic tracing. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-10 05:53:16 +07:00
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
#define IRQENTRY_TEXT \
ALIGN_FUNCTION(); \
VMLINUX_SYMBOL(__irqentry_text_start) = .; \
*(.irqentry.text) \
VMLINUX_SYMBOL(__irqentry_text_end) = .;
#else
#define IRQENTRY_TEXT
#endif
Add missing init section definitions When adding __devinitconst etc. the __initconst variant were missed. Add this one and proper definitions for .head.text for use in .S files. The naming .head.text is preferred over .text.head as the latter will conflict for a function named head when introducing -ffunctions-sections. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-02-20 03:00:18 +07:00
/* Section used for early init (in .S files) */
Add new HEAD_TEXT_SECTION macro. This patch is preparation for replacing all uses of ".head.text" or ".text.head" in the kernel with macros, so that the section name can later be changed without having to touch a lot of the kernel. Since some linker scripts do more complex things than referencing HEAD_TEXT, we add a HEAD_TEXT_SECTION macro that just contains the actual name. I've defined HEAD_TEXT_SECTION in a new header, include/linux/section-names.h, so that this section name only needs to appear in one place. I anticipate creating similar macro structures for a number of other section names. The long-term goal here is to be able to change the kernel's magic section names to those that are compatible with -ffunction-sections -fdata-sections. This requires renaming all magic sections with names of the form ".text.foo". Signed-off-by: Tim Abbott <tabbott@mit.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-26 09:10:56 +07:00
#define HEAD_TEXT *(HEAD_TEXT_SECTION)
Add missing init section definitions When adding __devinitconst etc. the __initconst variant were missed. Add this one and proper definitions for .head.text for use in .S files. The naming .head.text is preferred over .text.head as the latter will conflict for a function named head when introducing -ffunctions-sections. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-02-20 03:00:18 +07:00
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
#define HEAD_SECTION \
.head.text : AT(ADDR(.head.text) - LOAD_OFFSET) { \
HEAD_TEXT \
}
/*
* Exception table
*/
#define EXCEPTION_TABLE(align) \
. = ALIGN(align); \
__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ex_table) = .; \
*(__ex_table) \
VMLINUX_SYMBOL(__stop___ex_table) = .; \
}
/*
* Init task
*/
#define INIT_TASK_DATA(align) \
. = ALIGN(align); \
.data.init_task : { \
INIT_TASK \
}
all archs: consolidate init and exit sections in vmlinux.lds.h This patch consolidate all definitions of .init.text, .init.data and .exit.text, .exit.data section definitions in the generic vmlinux.lds.h. This is a preparational patch - alone it does not buy us much good. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-20 20:15:03 +07:00
/* init and exit section handling */
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
#define INIT_DATA \
*(.init.data) \
DEV_DISCARD(init.data) \
CPU_DISCARD(init.data) \
MEM_DISCARD(init.data) \
initconst adjustments - add .init.rodata to INIT_DATA, and group all initconst flavors together - move strings generated from __setup_param() into .init.rodata - add .*init.rodata to modpost's sets of init sections - make modpost warn about references between meminit and cpuinit as well as memexit and cpuexit sections (as CPU and memory hotplug are independently selectable features) Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-03-12 17:58:33 +07:00
*(.init.rodata) \
DEV_DISCARD(init.rodata) \
CPU_DISCARD(init.rodata) \
dynamic debug: combine dprintk and dynamic printk This patch combines Greg Bank's dprintk() work with the existing dynamic printk patchset, we are now calling it 'dynamic debug'. The new feature of this patchset is a richer /debugfs control file interface, (an example output from my system is at the bottom), which allows fined grained control over the the debug output. The output can be controlled by function, file, module, format string, and line number. for example, enabled all debug messages in module 'nf_conntrack': echo -n 'module nf_conntrack +p' > /mnt/debugfs/dynamic_debug/control to disable them: echo -n 'module nf_conntrack -p' > /mnt/debugfs/dynamic_debug/control A further explanation can be found in the documentation patch. Signed-off-by: Greg Banks <gnb@sgi.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-02-05 23:51:38 +07:00
MEM_DISCARD(init.rodata)
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
#define INIT_TEXT \
*(.init.text) \
DEV_DISCARD(init.text) \
CPU_DISCARD(init.text) \
MEM_DISCARD(init.text)
#define EXIT_DATA \
*(.exit.data) \
DEV_DISCARD(exit.data) \
DEV_DISCARD(exit.rodata) \
CPU_DISCARD(exit.data) \
CPU_DISCARD(exit.rodata) \
MEM_DISCARD(exit.data) \
MEM_DISCARD(exit.rodata)
all archs: consolidate init and exit sections in vmlinux.lds.h This patch consolidate all definitions of .init.text, .init.data and .exit.text, .exit.data section definitions in the generic vmlinux.lds.h. This is a preparational patch - alone it does not buy us much good. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-20 20:15:03 +07:00
Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Adrian Bunk <bunk@kernel.org>
2008-01-21 02:07:28 +07:00
#define EXIT_TEXT \
*(.exit.text) \
DEV_DISCARD(exit.text) \
CPU_DISCARD(exit.text) \
MEM_DISCARD(exit.text)
all archs: consolidate init and exit sections in vmlinux.lds.h This patch consolidate all definitions of .init.text, .init.data and .exit.text, .exit.data section definitions in the generic vmlinux.lds.h. This is a preparational patch - alone it does not buy us much good. Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-20 20:15:03 +07:00
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
/*
* bss (Block Started by Symbol) - uninitialized data
* zeroed during startup
*/
#define SBSS \
.sbss : AT(ADDR(.sbss) - LOAD_OFFSET) { \
*(.sbss) \
*(.scommon) \
}
#define BSS(bss_align) \
. = ALIGN(bss_align); \
.bss : AT(ADDR(.bss) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__bss_start) = .; \
*(.bss.page_aligned) \
*(.dynbss) \
*(.bss) \
*(COMMON) \
VMLINUX_SYMBOL(__bss_stop) = .; \
}
/*
* DWARF debug sections.
* Symbols in the DWARF debugging sections are relative to
* the beginning of the section so we begin them at 0.
*/
[PATCH] i386 / uml: add dwarf sections to static link script Inside the linker script, insert the code for DWARF debug info sections. This may help GDB'ing a Uml binary. Actually, it seems that ld is able to guess what I added correctly, but normal linker scripts include this section so it should be correct anyway adding it. On request by Sam Ravnborg <sam@ravnborg.org>, I've added it to asm-generic/vmlinux.lds.s. I've also moved there the stabs debug section, used the new macro in i386 linker script and added DWARF debug section to that. In the truth, I've not been able to verify the difference in GDB behaviour after this change (I've seen large improvements with another patch). This may depend on my binutils version, older one may have worse defaults. However, this section is present in normal linker script, so add it at least for the sake of cleanness. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-11 00:44:54 +07:00
#define DWARF_DEBUG \
/* DWARF 1 */ \
.debug 0 : { *(.debug) } \
.line 0 : { *(.line) } \
/* GNU DWARF 1 extensions */ \
.debug_srcinfo 0 : { *(.debug_srcinfo) } \
.debug_sfnames 0 : { *(.debug_sfnames) } \
/* DWARF 1.1 and DWARF 2 */ \
.debug_aranges 0 : { *(.debug_aranges) } \
.debug_pubnames 0 : { *(.debug_pubnames) } \
/* DWARF 2 */ \
.debug_info 0 : { *(.debug_info \
.gnu.linkonce.wi.*) } \
.debug_abbrev 0 : { *(.debug_abbrev) } \
.debug_line 0 : { *(.debug_line) } \
.debug_frame 0 : { *(.debug_frame) } \
.debug_str 0 : { *(.debug_str) } \
.debug_loc 0 : { *(.debug_loc) } \
.debug_macinfo 0 : { *(.debug_macinfo) } \
/* SGI/MIPS DWARF 2 extensions */ \
.debug_weaknames 0 : { *(.debug_weaknames) } \
.debug_funcnames 0 : { *(.debug_funcnames) } \
.debug_typenames 0 : { *(.debug_typenames) } \
.debug_varnames 0 : { *(.debug_varnames) } \
/* Stabs debugging sections. */
#define STABS_DEBUG \
.stab 0 : { *(.stab) } \
.stabstr 0 : { *(.stabstr) } \
.stab.excl 0 : { *(.stab.excl) } \
.stab.exclstr 0 : { *(.stab.exclstr) } \
.stab.index 0 : { *(.stab.index) } \
.stab.indexstr 0 : { *(.stab.indexstr) } \
.comment 0 : { *(.comment) }
[PATCH] x86: put .note.* sections into a PT_NOTE segment in vmlinux This patch will pack any .note.* section into a PT_NOTE segment in the output file. To do this, we tell ld that we need a PT_NOTE segment. This requires us to start explicitly mapping sections to segments, so we also need to explicitly create PT_LOAD segments for text and data, and map the sections to them appropriately. Fortunately, each section will default to its previous section's segment, so it doesn't take many changes to vmlinux.lds.S. This only changes i386 for now, but I presume the corresponding changes for other architectures will be as simple. This change also adds <linux/elfnote.h>, which defines C and Assembler macros for actually creating ELF notes. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 13:32:26 +07:00
move BUG_TABLE into RODATA Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:41 +07:00
#ifdef CONFIG_GENERIC_BUG
[PATCH] Generic BUG implementation This patch adds common handling for kernel BUGs, for use by architectures as they wish. The code is derived from arch/powerpc. The advantages of having common BUG handling are: - consistent BUG reporting across architectures - shared implementation of out-of-line file/line data - implement CONFIG_DEBUG_BUGVERBOSE consistently This means that in inline impact of BUG is just the illegal instruction itself, which is an improvement for i386 and x86-64. A BUG is represented in the instruction stream as an illegal instruction, which has file/line information associated with it. This extra information is stored in the __bug_table section in the ELF file. When the kernel gets an illegal instruction, it first confirms it might possibly be from a BUG (ie, in kernel mode, the right illegal instruction). It then calls report_bug(). This searches __bug_table for a matching instruction pointer, and if found, prints the corresponding file/line information. If report_bug() determines that it wasn't a BUG which caused the trap, it returns BUG_TRAP_TYPE_NONE. Some architectures (powerpc) implement WARN using the same mechanism; if the illegal instruction was the result of a WARN, then report_bug(Q) returns CONFIG_DEBUG_BUGVERBOSE; otherwise it returns BUG_TRAP_TYPE_BUG. lib/bug.c keeps a list of loaded modules which can be searched for __bug_table entries. The architecture must call module_bug_finalize()/module_bug_cleanup() from its corresponding module_finalize/cleanup functions. Unsetting CONFIG_DEBUG_BUGVERBOSE will reduce the kernel size by some amount. At the very least, filename and line information will not be recorded for each but, but architectures may decide to store no extra information per BUG at all. Unfortunately, gcc doesn't have a general way to mark an asm() as noreturn, so architectures will generally have to include an infinite loop (or similar) in the BUG code, so that gcc knows execution won't continue beyond that point. gcc does have a __builtin_trap() operator which may be useful to achieve the same effect, unfortunately it cannot be used to actually implement the BUG itself, because there's no way to get the instruction's address for use in generating the __bug_table entry. [randy.dunlap@oracle.com: Handle BUG=n, GENERIC_BUG=n to prevent build errors] [bunk@stusta.de: include/linux/bug.h must always #include <linux/module.h] Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Andi Kleen <ak@muc.de> Cc: Hugh Dickens <hugh@veritas.com> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 17:36:19 +07:00
#define BUG_TABLE \
. = ALIGN(8); \
__bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) { \
Missing symbol prefix on vmlinux.lds.h ARCH=h8300: init/main.c:781: undefined reference to `___early_initcall_end' Same problem have __start___bug_table __stop___bug_table __tracedata_start __tracedata_end __per_cpu_start __per_cpu_end When defining a symbol in vmlinux.lds, use the VMLINUX_SYMBOL macro. VMLINUX_SYMBOL adds a prefix charactor. You can't just use straight symbol names in common header files as they dont take into consideration weird arch-specific ABI conventions. in the case of Blackfin/h8300, the ABI dictates that any C-visible symbols have an underscore prefixed to them. Thus all symbols in vmlinux.lds.h need to be wrapped in VMLINUX_SYMBOL() so that each arch can put hide this magic in their own files. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Mike Frysinger" <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-31 14:07:29 +07:00
VMLINUX_SYMBOL(__start___bug_table) = .; \
[PATCH] Generic BUG implementation This patch adds common handling for kernel BUGs, for use by architectures as they wish. The code is derived from arch/powerpc. The advantages of having common BUG handling are: - consistent BUG reporting across architectures - shared implementation of out-of-line file/line data - implement CONFIG_DEBUG_BUGVERBOSE consistently This means that in inline impact of BUG is just the illegal instruction itself, which is an improvement for i386 and x86-64. A BUG is represented in the instruction stream as an illegal instruction, which has file/line information associated with it. This extra information is stored in the __bug_table section in the ELF file. When the kernel gets an illegal instruction, it first confirms it might possibly be from a BUG (ie, in kernel mode, the right illegal instruction). It then calls report_bug(). This searches __bug_table for a matching instruction pointer, and if found, prints the corresponding file/line information. If report_bug() determines that it wasn't a BUG which caused the trap, it returns BUG_TRAP_TYPE_NONE. Some architectures (powerpc) implement WARN using the same mechanism; if the illegal instruction was the result of a WARN, then report_bug(Q) returns CONFIG_DEBUG_BUGVERBOSE; otherwise it returns BUG_TRAP_TYPE_BUG. lib/bug.c keeps a list of loaded modules which can be searched for __bug_table entries. The architecture must call module_bug_finalize()/module_bug_cleanup() from its corresponding module_finalize/cleanup functions. Unsetting CONFIG_DEBUG_BUGVERBOSE will reduce the kernel size by some amount. At the very least, filename and line information will not be recorded for each but, but architectures may decide to store no extra information per BUG at all. Unfortunately, gcc doesn't have a general way to mark an asm() as noreturn, so architectures will generally have to include an infinite loop (or similar) in the BUG code, so that gcc knows execution won't continue beyond that point. gcc does have a __builtin_trap() operator which may be useful to achieve the same effect, unfortunately it cannot be used to actually implement the BUG itself, because there's no way to get the instruction's address for use in generating the __bug_table entry. [randy.dunlap@oracle.com: Handle BUG=n, GENERIC_BUG=n to prevent build errors] [bunk@stusta.de: include/linux/bug.h must always #include <linux/module.h] Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Andi Kleen <ak@muc.de> Cc: Hugh Dickens <hugh@veritas.com> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 17:36:19 +07:00
*(__bug_table) \
Missing symbol prefix on vmlinux.lds.h ARCH=h8300: init/main.c:781: undefined reference to `___early_initcall_end' Same problem have __start___bug_table __stop___bug_table __tracedata_start __tracedata_end __per_cpu_start __per_cpu_end When defining a symbol in vmlinux.lds, use the VMLINUX_SYMBOL macro. VMLINUX_SYMBOL adds a prefix charactor. You can't just use straight symbol names in common header files as they dont take into consideration weird arch-specific ABI conventions. in the case of Blackfin/h8300, the ABI dictates that any C-visible symbols have an underscore prefixed to them. Thus all symbols in vmlinux.lds.h need to be wrapped in VMLINUX_SYMBOL() so that each arch can put hide this magic in their own files. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Mike Frysinger" <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-31 14:07:29 +07:00
VMLINUX_SYMBOL(__stop___bug_table) = .; \
[PATCH] Generic BUG implementation This patch adds common handling for kernel BUGs, for use by architectures as they wish. The code is derived from arch/powerpc. The advantages of having common BUG handling are: - consistent BUG reporting across architectures - shared implementation of out-of-line file/line data - implement CONFIG_DEBUG_BUGVERBOSE consistently This means that in inline impact of BUG is just the illegal instruction itself, which is an improvement for i386 and x86-64. A BUG is represented in the instruction stream as an illegal instruction, which has file/line information associated with it. This extra information is stored in the __bug_table section in the ELF file. When the kernel gets an illegal instruction, it first confirms it might possibly be from a BUG (ie, in kernel mode, the right illegal instruction). It then calls report_bug(). This searches __bug_table for a matching instruction pointer, and if found, prints the corresponding file/line information. If report_bug() determines that it wasn't a BUG which caused the trap, it returns BUG_TRAP_TYPE_NONE. Some architectures (powerpc) implement WARN using the same mechanism; if the illegal instruction was the result of a WARN, then report_bug(Q) returns CONFIG_DEBUG_BUGVERBOSE; otherwise it returns BUG_TRAP_TYPE_BUG. lib/bug.c keeps a list of loaded modules which can be searched for __bug_table entries. The architecture must call module_bug_finalize()/module_bug_cleanup() from its corresponding module_finalize/cleanup functions. Unsetting CONFIG_DEBUG_BUGVERBOSE will reduce the kernel size by some amount. At the very least, filename and line information will not be recorded for each but, but architectures may decide to store no extra information per BUG at all. Unfortunately, gcc doesn't have a general way to mark an asm() as noreturn, so architectures will generally have to include an infinite loop (or similar) in the BUG code, so that gcc knows execution won't continue beyond that point. gcc does have a __builtin_trap() operator which may be useful to achieve the same effect, unfortunately it cannot be used to actually implement the BUG itself, because there's no way to get the instruction's address for use in generating the __bug_table entry. [randy.dunlap@oracle.com: Handle BUG=n, GENERIC_BUG=n to prevent build errors] [bunk@stusta.de: include/linux/bug.h must always #include <linux/module.h] Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Andi Kleen <ak@muc.de> Cc: Hugh Dickens <hugh@veritas.com> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 17:36:19 +07:00
}
move BUG_TABLE into RODATA Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:41 +07:00
#else
#define BUG_TABLE
#endif
[PATCH] Generic BUG implementation This patch adds common handling for kernel BUGs, for use by architectures as they wish. The code is derived from arch/powerpc. The advantages of having common BUG handling are: - consistent BUG reporting across architectures - shared implementation of out-of-line file/line data - implement CONFIG_DEBUG_BUGVERBOSE consistently This means that in inline impact of BUG is just the illegal instruction itself, which is an improvement for i386 and x86-64. A BUG is represented in the instruction stream as an illegal instruction, which has file/line information associated with it. This extra information is stored in the __bug_table section in the ELF file. When the kernel gets an illegal instruction, it first confirms it might possibly be from a BUG (ie, in kernel mode, the right illegal instruction). It then calls report_bug(). This searches __bug_table for a matching instruction pointer, and if found, prints the corresponding file/line information. If report_bug() determines that it wasn't a BUG which caused the trap, it returns BUG_TRAP_TYPE_NONE. Some architectures (powerpc) implement WARN using the same mechanism; if the illegal instruction was the result of a WARN, then report_bug(Q) returns CONFIG_DEBUG_BUGVERBOSE; otherwise it returns BUG_TRAP_TYPE_BUG. lib/bug.c keeps a list of loaded modules which can be searched for __bug_table entries. The architecture must call module_bug_finalize()/module_bug_cleanup() from its corresponding module_finalize/cleanup functions. Unsetting CONFIG_DEBUG_BUGVERBOSE will reduce the kernel size by some amount. At the very least, filename and line information will not be recorded for each but, but architectures may decide to store no extra information per BUG at all. Unfortunately, gcc doesn't have a general way to mark an asm() as noreturn, so architectures will generally have to include an infinite loop (or similar) in the BUG code, so that gcc knows execution won't continue beyond that point. gcc does have a __builtin_trap() operator which may be useful to achieve the same effect, unfortunately it cannot be used to actually implement the BUG itself, because there's no way to get the instruction's address for use in generating the __bug_table entry. [randy.dunlap@oracle.com: Handle BUG=n, GENERIC_BUG=n to prevent build errors] [bunk@stusta.de: include/linux/bug.h must always #include <linux/module.h] Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Andi Kleen <ak@muc.de> Cc: Hugh Dickens <hugh@veritas.com> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 17:36:19 +07:00
x86: move tracedata to RODATA .. allowing it to be write-protected just as other read-only data under CONFIG_DEBUG_RODATA. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:41 +07:00
#ifdef CONFIG_PM_TRACE
#define TRACEDATA \
. = ALIGN(4); \
.tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) { \
Missing symbol prefix on vmlinux.lds.h ARCH=h8300: init/main.c:781: undefined reference to `___early_initcall_end' Same problem have __start___bug_table __stop___bug_table __tracedata_start __tracedata_end __per_cpu_start __per_cpu_end When defining a symbol in vmlinux.lds, use the VMLINUX_SYMBOL macro. VMLINUX_SYMBOL adds a prefix charactor. You can't just use straight symbol names in common header files as they dont take into consideration weird arch-specific ABI conventions. in the case of Blackfin/h8300, the ABI dictates that any C-visible symbols have an underscore prefixed to them. Thus all symbols in vmlinux.lds.h need to be wrapped in VMLINUX_SYMBOL() so that each arch can put hide this magic in their own files. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Mike Frysinger" <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-31 14:07:29 +07:00
VMLINUX_SYMBOL(__tracedata_start) = .; \
x86: move tracedata to RODATA .. allowing it to be write-protected just as other read-only data under CONFIG_DEBUG_RODATA. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:41 +07:00
*(.tracedata) \
Missing symbol prefix on vmlinux.lds.h ARCH=h8300: init/main.c:781: undefined reference to `___early_initcall_end' Same problem have __start___bug_table __stop___bug_table __tracedata_start __tracedata_end __per_cpu_start __per_cpu_end When defining a symbol in vmlinux.lds, use the VMLINUX_SYMBOL macro. VMLINUX_SYMBOL adds a prefix charactor. You can't just use straight symbol names in common header files as they dont take into consideration weird arch-specific ABI conventions. in the case of Blackfin/h8300, the ABI dictates that any C-visible symbols have an underscore prefixed to them. Thus all symbols in vmlinux.lds.h need to be wrapped in VMLINUX_SYMBOL() so that each arch can put hide this magic in their own files. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Mike Frysinger" <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-31 14:07:29 +07:00
VMLINUX_SYMBOL(__tracedata_end) = .; \
x86: move tracedata to RODATA .. allowing it to be write-protected just as other read-only data under CONFIG_DEBUG_RODATA. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:41 +07:00
}
#else
#define TRACEDATA
#endif
[PATCH] x86: put .note.* sections into a PT_NOTE segment in vmlinux This patch will pack any .note.* section into a PT_NOTE segment in the output file. To do this, we tell ld that we need a PT_NOTE segment. This requires us to start explicitly mapping sections to segments, so we also need to explicitly create PT_LOAD segments for text and data, and map the sections to them appropriately. Fortunately, each section will default to its previous section's segment, so it doesn't take many changes to vmlinux.lds.S. This only changes i386 for now, but I presume the corresponding changes for other architectures will be as simple. This change also adds <linux/elfnote.h>, which defines C and Assembler macros for actually creating ELF notes. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 13:32:26 +07:00
#define NOTES \
i386: Put allocated ELF notes in read-only data segment This changes the i386 linker script and the asm-generic macro it uses so that ELF note sections with SHF_ALLOC set are linked into the kernel image along with other read-only data. The PT_NOTE also points to their location. This paves the way for putting useful build-time information into ELF notes that can be found easily later in a kernel memory dump. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andi Kleen <ak@suse.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 15:48:36 +07:00
.notes : AT(ADDR(.notes) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start_notes) = .; \
*(.note.*) \
VMLINUX_SYMBOL(__stop_notes) = .; \
}
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
#define INIT_SETUP(initsetup_align) \
. = ALIGN(initsetup_align); \
VMLINUX_SYMBOL(__setup_start) = .; \
*(.init.setup) \
VMLINUX_SYMBOL(__setup_end) = .;
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
#define INITCALLS \
Better interface for hooking early initcalls Added early initcall (pre-SMP) support, using an identical interface to that of regular initcalls. Functions called from do_pre_smp_initcalls() could be converted to use this cleaner interface. This is required by CPU hotplug, because early users have to register notifiers before going SMP. One such CPU hotplug user is the relay interface with buffer-only channels, which needs to register such a notifier, to be usable in early code. This in turn is used by kmemtrace. Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Cc: Tom Zanussi <tzanussi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 09:45:11 +07:00
*(.initcallearly.init) \
Missing symbol prefix on vmlinux.lds.h ARCH=h8300: init/main.c:781: undefined reference to `___early_initcall_end' Same problem have __start___bug_table __stop___bug_table __tracedata_start __tracedata_end __per_cpu_start __per_cpu_end When defining a symbol in vmlinux.lds, use the VMLINUX_SYMBOL macro. VMLINUX_SYMBOL adds a prefix charactor. You can't just use straight symbol names in common header files as they dont take into consideration weird arch-specific ABI conventions. in the case of Blackfin/h8300, the ABI dictates that any C-visible symbols have an underscore prefixed to them. Thus all symbols in vmlinux.lds.h need to be wrapped in VMLINUX_SYMBOL() so that each arch can put hide this magic in their own files. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Mike Frysinger" <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-31 14:07:29 +07:00
VMLINUX_SYMBOL(__early_initcall_end) = .; \
Add "pure_initcall" for static variable initialization This is a quick hack to overcome the fact that SRCU currently does not allow static initializers, and we need to sometimes initialize those things before any other initializers (even "core" ones) can do so. Currently we don't allow this at all for modules, and the only user that needs is right now is cpufreq. As reported by Thomas Gleixner: "Commit b4dfdbb3c707474a2254c5b4d7e62be31a4b7da9 ("[PATCH] cpufreq: make the transition_notifier chain use SRCU breaks cpu frequency notification users, which register the callback > on core_init level." Cc: Thomas Gleixner <tglx@timesys.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Andrew Morton <akpm@osdl.org>, Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-21 02:47:18 +07:00
*(.initcall0.init) \
*(.initcall0s.init) \
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
*(.initcall1.init) \
[PATCH] drivers: wait for threaded probes between initcall levels The multithreaded-probing code has a problem: after one initcall level (eg, core_initcall) has been processed, we will then start processing the next level (postcore_initcall) while the kernel threads which are handling core_initcall are still executing. This breaks the guarantees which the layered initcalls previously gave us. IOW, we want to be multithreaded _within_ an initcall level, but not between different levels. Fix that up by causing the probing code to wait for all outstanding probes at one level to complete before we start processing the next level. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:42:37 +07:00
*(.initcall1s.init) \
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
*(.initcall2.init) \
[PATCH] drivers: wait for threaded probes between initcall levels The multithreaded-probing code has a problem: after one initcall level (eg, core_initcall) has been processed, we will then start processing the next level (postcore_initcall) while the kernel threads which are handling core_initcall are still executing. This breaks the guarantees which the layered initcalls previously gave us. IOW, we want to be multithreaded _within_ an initcall level, but not between different levels. Fix that up by causing the probing code to wait for all outstanding probes at one level to complete before we start processing the next level. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:42:37 +07:00
*(.initcall2s.init) \
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
*(.initcall3.init) \
[PATCH] drivers: wait for threaded probes between initcall levels The multithreaded-probing code has a problem: after one initcall level (eg, core_initcall) has been processed, we will then start processing the next level (postcore_initcall) while the kernel threads which are handling core_initcall are still executing. This breaks the guarantees which the layered initcalls previously gave us. IOW, we want to be multithreaded _within_ an initcall level, but not between different levels. Fix that up by causing the probing code to wait for all outstanding probes at one level to complete before we start processing the next level. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:42:37 +07:00
*(.initcall3s.init) \
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
*(.initcall4.init) \
[PATCH] drivers: wait for threaded probes between initcall levels The multithreaded-probing code has a problem: after one initcall level (eg, core_initcall) has been processed, we will then start processing the next level (postcore_initcall) while the kernel threads which are handling core_initcall are still executing. This breaks the guarantees which the layered initcalls previously gave us. IOW, we want to be multithreaded _within_ an initcall level, but not between different levels. Fix that up by causing the probing code to wait for all outstanding probes at one level to complete before we start processing the next level. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:42:37 +07:00
*(.initcall4s.init) \
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
*(.initcall5.init) \
[PATCH] drivers: wait for threaded probes between initcall levels The multithreaded-probing code has a problem: after one initcall level (eg, core_initcall) has been processed, we will then start processing the next level (postcore_initcall) while the kernel threads which are handling core_initcall are still executing. This breaks the guarantees which the layered initcalls previously gave us. IOW, we want to be multithreaded _within_ an initcall level, but not between different levels. Fix that up by causing the probing code to wait for all outstanding probes at one level to complete before we start processing the next level. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:42:37 +07:00
*(.initcall5s.init) \
Make sure we populate the initroot filesystem late enough We should not initialize rootfs before all the core initializers have run. So do it as a separate stage just before starting the regular driver initializers. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-12 03:12:04 +07:00
*(.initcallrootfs.init) \
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
*(.initcall6.init) \
[PATCH] drivers: wait for threaded probes between initcall levels The multithreaded-probing code has a problem: after one initcall level (eg, core_initcall) has been processed, we will then start processing the next level (postcore_initcall) while the kernel threads which are handling core_initcall are still executing. This breaks the guarantees which the layered initcalls previously gave us. IOW, we want to be multithreaded _within_ an initcall level, but not between different levels. Fix that up by causing the probing code to wait for all outstanding probes at one level to complete before we start processing the next level. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:42:37 +07:00
*(.initcall6s.init) \
*(.initcall7.init) \
*(.initcall7s.init)
[PATCH] vmlinux.lds: consolidate initcall sections Add a vmlinux.lds.h helper macro for defining the eight-level initcall table, teach all the architectures to use it. This is a prerequisite for a patch which performs initcall synchronisation for multithreaded-probing. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> [ Added AVR32 as well ] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 01:41:44 +07:00
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
#define INIT_CALLS \
VMLINUX_SYMBOL(__initcall_start) = .; \
INITCALLS \
VMLINUX_SYMBOL(__initcall_end) = .;
#define CON_INITCALL \
VMLINUX_SYMBOL(__con_initcall_start) = .; \
*(.con_initcall.init) \
VMLINUX_SYMBOL(__con_initcall_end) = .;
#define SECURITY_INITCALL \
VMLINUX_SYMBOL(__security_initcall_start) = .; \
*(.security_initcall.init) \
VMLINUX_SYMBOL(__security_initcall_end) = .;
#ifdef CONFIG_BLK_DEV_INITRD
#define INIT_RAM_FS \
. = ALIGN(PAGE_SIZE); \
VMLINUX_SYMBOL(__initramfs_start) = .; \
*(.init.ramfs) \
VMLINUX_SYMBOL(__initramfs_end) = .;
#else
#define INITRAMFS
#endif
x86: make percpu symbols zerobased on SMP [ Based on original patch from Christoph Lameter and Mike Travis. ] This patch makes percpu symbols zerobased on x86_64 SMP by adding PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on the percpu output section and using it in vmlinux_64.lds.S. A new PHDR is added as existing ones cannot contain sections near address zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which always points to the vaddr of the loaded percpu data.init region. The following adjustments have been made to accomodate the address change. * code to locate percpu gdt_page in head_64.S is updated to add the load address to the gdt_page offset. * __per_cpu_load is used in places where access to the init data area is necessary. * pda->data_offset is initialized soon after C code is entered as zero value doesn't work anymore. This patch is mostly taken from Mike Travis' "x86_64: Base percpu variables at zero" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-13 18:41:35 +07:00
/**
linker script: kill PERCPU_VADDR_PREALLOC() Impact: cleanup With .data.percpu.first in place, PERCPU_VADDR_PREALLOC() is no longer necessary. Kill it. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-19 10:21:28 +07:00
* PERCPU_VADDR - define output section for percpu area
x86: make percpu symbols zerobased on SMP [ Based on original patch from Christoph Lameter and Mike Travis. ] This patch makes percpu symbols zerobased on x86_64 SMP by adding PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on the percpu output section and using it in vmlinux_64.lds.S. A new PHDR is added as existing ones cannot contain sections near address zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which always points to the vaddr of the loaded percpu data.init region. The following adjustments have been made to accomodate the address change. * code to locate percpu gdt_page in head_64.S is updated to add the load address to the gdt_page offset. * __per_cpu_load is used in places where access to the init data area is necessary. * pda->data_offset is initialized soon after C code is entered as zero value doesn't work anymore. This patch is mostly taken from Mike Travis' "x86_64: Base percpu variables at zero" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-13 18:41:35 +07:00
* @vaddr: explicit base address (optional)
* @phdr: destination PHDR (optional)
*
* Macro which expands to output section for percpu area. If @vaddr
* is not blank, it specifies explicit base address and all percpu
* symbols will be offset from the given address. If blank, @vaddr
* always equals @laddr + LOAD_OFFSET.
*
* @phdr defines the output PHDR to use if not blank. Be warned that
* output PHDR is sticky. If @phdr is specified, the next output
* section in the linker script will go there too. @phdr should have
* a leading colon.
*
linker script: use separate simpler definition for PERCPU() Impact: fix linker screwup on x86_32 Recent x86_64 zerobased patches introduced PERCPU_VADDR() to put .data.percpu to a predefined address and re-defined PERCPU() in terms of it. The new macro defined one extra symbol, __per_cpu_load, for LMA of the section so that the init data could be accessed. This new symbol introduced the following problems to x86_32. 1. If __per_cpu_load is defined outside of .data.percpu as an absolute symbol, relocation generation for relocatable kernel fails due to absolute relocation. 2. If __per_cpu_load is put inside .data.percpu with absolute address assignment to work around #1, linker gets confused and under certain configurations ends up relocating the symbol against .data.percpu such that the load address gets added on top of already set load address. As x86_32 doesn't use predefined address for .data.percpu, there's no need for it to care about the possibility of __per_cpu_load being different from __per_cpu_start. This patch defines PERCPU() separately so that __per_cpu_load is defined inside .data.percpu so that everything is ordinary linking-wise. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-30 14:32:22 +07:00
* Note that this macros defines __per_cpu_load as an absolute symbol.
* If there is no need to put the percpu section at a predetermined
* address, use PERCPU().
x86: make percpu symbols zerobased on SMP [ Based on original patch from Christoph Lameter and Mike Travis. ] This patch makes percpu symbols zerobased on x86_64 SMP by adding PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on the percpu output section and using it in vmlinux_64.lds.S. A new PHDR is added as existing ones cannot contain sections near address zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which always points to the vaddr of the loaded percpu data.init region. The following adjustments have been made to accomodate the address change. * code to locate percpu gdt_page in head_64.S is updated to add the load address to the gdt_page offset. * __per_cpu_load is used in places where access to the init data area is necessary. * pda->data_offset is initialized soon after C code is entered as zero value doesn't work anymore. This patch is mostly taken from Mike Travis' "x86_64: Base percpu variables at zero" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-13 18:41:35 +07:00
*/
#define PERCPU_VADDR(vaddr, phdr) \
Revert "generic, x86: fix __per_cpu_load relocation" This reverts commit 5a611268b69f05262936dd177205acbce4471358. It is causing occasional boot crashes, caused by certain linker versions (GNU ld version 2.18.50.0.6-2 20080403) messing up: 82dcc000 D __per_cpu_load c16e6000 A __per_cpu_load_abs The __per_cpu_load value is out of whack. Hpa noticed the following detail: * (gdb) p/x -(0xc16e6000-0x82dcc000) * $2 = 0xc16e6000 * I.e. one is the other << 1 The two symbols should be equal. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-29 23:10:12 +07:00
VMLINUX_SYMBOL(__per_cpu_load) = .; \
.data.percpu vaddr : AT(VMLINUX_SYMBOL(__per_cpu_load) \
linker script: kill PERCPU_VADDR_PREALLOC() Impact: cleanup With .data.percpu.first in place, PERCPU_VADDR_PREALLOC() is no longer necessary. Kill it. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-19 10:21:28 +07:00
- LOAD_OFFSET) { \
VMLINUX_SYMBOL(__per_cpu_start) = .; \
percpu: refactor percpu.h Impact: cleanup Refactor the DEFINE_PER_CPU_* macros and add .data.percpu.first section. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-19 10:21:27 +07:00
*(.data.percpu.first) \
percpu: introduce DEFINE_PER_CPU_PAGE_ALIGNED() macro While examining holes in percpu section I found this : c05f5000 D per_cpu__current_task c05f5000 D __per_cpu_start c05f5004 D per_cpu__cpu_number c05f5008 D per_cpu__irq_regs c05f500c d per_cpu__cpu_devices c05f5040 D per_cpu__cyc2ns <Big Hole of about 4000 bytes> c05f6000 d per_cpu__cpuid4_info c05f6004 d per_cpu__cache_kobject c05f6008 d per_cpu__index_kobject <Big Hole of about 4000 bytes> c05f7000 D per_cpu__gdt_page This is because gdt_page is a percpu variable, defined with a page alignement, and linker is doing its job, two times because of .o nesting in the build process. I introduced a new macro DEFINE_PER_CPU_PAGE_ALIGNED() to avoid wasting this space. All page aligned variables (only one at this time) are put in a separate subsection .data.percpu.page_aligned, at the very begining of percpu zone. Before patch , on a x86_32 machine : .data.percpu 30232 3227471872 .data.percpu 22168 3227471872 Thats 8064 bytes saved for each CPU. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:40 +07:00
*(.data.percpu.page_aligned) \
define new percpu interface for shared data per cpu data section contains two types of data. One set which is exclusively accessed by the local cpu and the other set which is per cpu, but also shared by remote cpus. In the current kernel, these two sets are not clearely separated out. This can potentially cause the same data cacheline shared between the two sets of data, which will result in unnecessary bouncing of the cacheline between cpus. One way to fix the problem is to cacheline align the remotely accessed per cpu data, both at the beginning and at the end. Because of the padding at both ends, this will likely cause some memory wastage and also the interface to achieve this is not clean. This patch: Moves the remotely accessed per cpu data (which is currently marked as ____cacheline_aligned_in_smp) into a different section, where all the data elements are cacheline aligned. And as such, this differentiates the local only data and remotely accessed data cleanly. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Christoph Lameter <clameter@sgi.com> Cc: <linux-arch@vger.kernel.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 15:48:12 +07:00
*(.data.percpu) \
*(.data.percpu.shared_aligned) \
linker script: kill PERCPU_VADDR_PREALLOC() Impact: cleanup With .data.percpu.first in place, PERCPU_VADDR_PREALLOC() is no longer necessary. Kill it. Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-19 10:21:28 +07:00
VMLINUX_SYMBOL(__per_cpu_end) = .; \
} phdr \
Revert "generic, x86: fix __per_cpu_load relocation" This reverts commit 5a611268b69f05262936dd177205acbce4471358. It is causing occasional boot crashes, caused by certain linker versions (GNU ld version 2.18.50.0.6-2 20080403) messing up: 82dcc000 D __per_cpu_load c16e6000 A __per_cpu_load_abs The __per_cpu_load value is out of whack. Hpa noticed the following detail: * (gdb) p/x -(0xc16e6000-0x82dcc000) * $2 = 0xc16e6000 * I.e. one is the other << 1 The two symbols should be equal. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-29 23:10:12 +07:00
. = VMLINUX_SYMBOL(__per_cpu_load) + SIZEOF(.data.percpu);
x86: make percpu symbols zerobased on SMP [ Based on original patch from Christoph Lameter and Mike Travis. ] This patch makes percpu symbols zerobased on x86_64 SMP by adding PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on the percpu output section and using it in vmlinux_64.lds.S. A new PHDR is added as existing ones cannot contain sections near address zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which always points to the vaddr of the loaded percpu data.init region. The following adjustments have been made to accomodate the address change. * code to locate percpu gdt_page in head_64.S is updated to add the load address to the gdt_page offset. * __per_cpu_load is used in places where access to the init data area is necessary. * pda->data_offset is initialized soon after C code is entered as zero value doesn't work anymore. This patch is mostly taken from Mike Travis' "x86_64: Base percpu variables at zero" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-13 18:41:35 +07:00
/**
* PERCPU - define output section for percpu area, simple version
* @align: required alignment
*
* Align to @align and outputs output section for percpu area. This
* macro doesn't maniuplate @vaddr or @phdr and __per_cpu_load and
* __per_cpu_start will be identical.
linker script: use separate simpler definition for PERCPU() Impact: fix linker screwup on x86_32 Recent x86_64 zerobased patches introduced PERCPU_VADDR() to put .data.percpu to a predefined address and re-defined PERCPU() in terms of it. The new macro defined one extra symbol, __per_cpu_load, for LMA of the section so that the init data could be accessed. This new symbol introduced the following problems to x86_32. 1. If __per_cpu_load is defined outside of .data.percpu as an absolute symbol, relocation generation for relocatable kernel fails due to absolute relocation. 2. If __per_cpu_load is put inside .data.percpu with absolute address assignment to work around #1, linker gets confused and under certain configurations ends up relocating the symbol against .data.percpu such that the load address gets added on top of already set load address. As x86_32 doesn't use predefined address for .data.percpu, there's no need for it to care about the possibility of __per_cpu_load being different from __per_cpu_start. This patch defines PERCPU() separately so that __per_cpu_load is defined inside .data.percpu so that everything is ordinary linking-wise. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-30 14:32:22 +07:00
*
* This macro is equivalent to ALIGN(align); PERCPU_VADDR( , ) except
* that __per_cpu_load is defined as a relative symbol against
* .data.percpu which is required for relocatable x86_32
* configuration.
x86: make percpu symbols zerobased on SMP [ Based on original patch from Christoph Lameter and Mike Travis. ] This patch makes percpu symbols zerobased on x86_64 SMP by adding PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on the percpu output section and using it in vmlinux_64.lds.S. A new PHDR is added as existing ones cannot contain sections near address zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which always points to the vaddr of the loaded percpu data.init region. The following adjustments have been made to accomodate the address change. * code to locate percpu gdt_page in head_64.S is updated to add the load address to the gdt_page offset. * __per_cpu_load is used in places where access to the init data area is necessary. * pda->data_offset is initialized soon after C code is entered as zero value doesn't work anymore. This patch is mostly taken from Mike Travis' "x86_64: Base percpu variables at zero" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-13 18:41:35 +07:00
*/
define new percpu interface for shared data per cpu data section contains two types of data. One set which is exclusively accessed by the local cpu and the other set which is per cpu, but also shared by remote cpus. In the current kernel, these two sets are not clearely separated out. This can potentially cause the same data cacheline shared between the two sets of data, which will result in unnecessary bouncing of the cacheline between cpus. One way to fix the problem is to cacheline align the remotely accessed per cpu data, both at the beginning and at the end. Because of the padding at both ends, this will likely cause some memory wastage and also the interface to achieve this is not clean. This patch: Moves the remotely accessed per cpu data (which is currently marked as ____cacheline_aligned_in_smp) into a different section, where all the data elements are cacheline aligned. And as such, this differentiates the local only data and remotely accessed data cleanly. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Christoph Lameter <clameter@sgi.com> Cc: <linux-arch@vger.kernel.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 15:48:12 +07:00
#define PERCPU(align) \
. = ALIGN(align); \
linker script: use separate simpler definition for PERCPU() Impact: fix linker screwup on x86_32 Recent x86_64 zerobased patches introduced PERCPU_VADDR() to put .data.percpu to a predefined address and re-defined PERCPU() in terms of it. The new macro defined one extra symbol, __per_cpu_load, for LMA of the section so that the init data could be accessed. This new symbol introduced the following problems to x86_32. 1. If __per_cpu_load is defined outside of .data.percpu as an absolute symbol, relocation generation for relocatable kernel fails due to absolute relocation. 2. If __per_cpu_load is put inside .data.percpu with absolute address assignment to work around #1, linker gets confused and under certain configurations ends up relocating the symbol against .data.percpu such that the load address gets added on top of already set load address. As x86_32 doesn't use predefined address for .data.percpu, there's no need for it to care about the possibility of __per_cpu_load being different from __per_cpu_start. This patch defines PERCPU() separately so that __per_cpu_load is defined inside .data.percpu so that everything is ordinary linking-wise. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-30 14:32:22 +07:00
.data.percpu : AT(ADDR(.data.percpu) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__per_cpu_load) = .; \
VMLINUX_SYMBOL(__per_cpu_start) = .; \
*(.data.percpu.first) \
percpu: introduce DEFINE_PER_CPU_PAGE_ALIGNED() macro While examining holes in percpu section I found this : c05f5000 D per_cpu__current_task c05f5000 D __per_cpu_start c05f5004 D per_cpu__cpu_number c05f5008 D per_cpu__irq_regs c05f500c d per_cpu__cpu_devices c05f5040 D per_cpu__cyc2ns <Big Hole of about 4000 bytes> c05f6000 d per_cpu__cpuid4_info c05f6004 d per_cpu__cache_kobject c05f6008 d per_cpu__index_kobject <Big Hole of about 4000 bytes> c05f7000 D per_cpu__gdt_page This is because gdt_page is a percpu variable, defined with a page alignement, and linker is doing its job, two times because of .o nesting in the build process. I introduced a new macro DEFINE_PER_CPU_PAGE_ALIGNED() to avoid wasting this space. All page aligned variables (only one at this time) are put in a separate subsection .data.percpu.page_aligned, at the very begining of percpu zone. Before patch , on a x86_32 machine : .data.percpu 30232 3227471872 .data.percpu 22168 3227471872 Thats 8064 bytes saved for each CPU. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12 20:44:40 +07:00
*(.data.percpu.page_aligned) \
define new percpu interface for shared data per cpu data section contains two types of data. One set which is exclusively accessed by the local cpu and the other set which is per cpu, but also shared by remote cpus. In the current kernel, these two sets are not clearely separated out. This can potentially cause the same data cacheline shared between the two sets of data, which will result in unnecessary bouncing of the cacheline between cpus. One way to fix the problem is to cacheline align the remotely accessed per cpu data, both at the beginning and at the end. Because of the padding at both ends, this will likely cause some memory wastage and also the interface to achieve this is not clean. This patch: Moves the remotely accessed per cpu data (which is currently marked as ____cacheline_aligned_in_smp) into a different section, where all the data elements are cacheline aligned. And as such, this differentiates the local only data and remotely accessed data cleanly. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Christoph Lameter <clameter@sgi.com> Cc: <linux-arch@vger.kernel.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 15:48:12 +07:00
*(.data.percpu) \
*(.data.percpu.shared_aligned) \
linker script: use separate simpler definition for PERCPU() Impact: fix linker screwup on x86_32 Recent x86_64 zerobased patches introduced PERCPU_VADDR() to put .data.percpu to a predefined address and re-defined PERCPU() in terms of it. The new macro defined one extra symbol, __per_cpu_load, for LMA of the section so that the init data could be accessed. This new symbol introduced the following problems to x86_32. 1. If __per_cpu_load is defined outside of .data.percpu as an absolute symbol, relocation generation for relocatable kernel fails due to absolute relocation. 2. If __per_cpu_load is put inside .data.percpu with absolute address assignment to work around #1, linker gets confused and under certain configurations ends up relocating the symbol against .data.percpu such that the load address gets added on top of already set load address. As x86_32 doesn't use predefined address for .data.percpu, there's no need for it to care about the possibility of __per_cpu_load being different from __per_cpu_start. This patch defines PERCPU() separately so that __per_cpu_load is defined inside .data.percpu so that everything is ordinary linking-wise. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-30 14:32:22 +07:00
VMLINUX_SYMBOL(__per_cpu_end) = .; \
}
Improve vmlinux.lds.h support for arch specific linker scripts To support alingment of the individual architecture specific linker scripts provide a set of general definitions in vmlinux.lds.h With these definitions applied the diverse linekr scripts can be reduced in line count and their readability are improved - IMO. A sample linker script is included to give the preferred order of the sections for the architectures that do not have any special requirments. These definitions are also a first step towards eventual support for -ffunction-sections. The definitions makes it much easier to do a global renaming of section names - but the main purpose is to clean up the linker scripts. Tim Aboot has provided a lot of inputs to improve the definitions - all faults are mine. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@mit.edu>
2009-06-08 01:46:37 +07:00
/*
* Definition of the high level *_SECTION macros
* They will fit only a subset of the architectures
*/
/*
* Writeable data.
* All sections are combined in a single .data section.
* The sections following CONSTRUCTORS are arranged so their
* typical alignment matches.
* A cacheline is typical/always less than a PAGE_SIZE so
* the sections that has this restriction (or similar)
* is located before the ones requiring PAGE_SIZE alignment.
* NOSAVE_DATA starts and ends with a PAGE_SIZE alignment which
* matches the requirment of PAGE_ALIGNED_DATA.
*
/* use 0 as page_align if page_aligned data is not used */
#define RW_DATA_SECTION(cacheline, nosave, pagealigned, inittask) \
. = ALIGN(PAGE_SIZE); \
.data : AT(ADDR(.data) - LOAD_OFFSET) { \
INIT_TASK(inittask) \
CACHELINE_ALIGNED_DATA(cacheline) \
READ_MOSTLY_DATA(cacheline) \
DATA_DATA \
CONSTRUCTORS \
NOSAVE_DATA(nosave) \
PAGE_ALIGNED_DATA(pagealigned) \
}
#define INIT_TEXT_SECTION(inittext_align) \
. = ALIGN(inittext_align); \
.init.text : AT(ADDR(.init.text) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(_sinittext) = .; \
INIT_TEXT \
VMLINUX_SYMBOL(_einittext) = .; \
}
#define INIT_DATA_SECTION(initsetup_align) \
.init.data : AT(ADDR(.init.data) - LOAD_OFFSET) { \
INIT_DATA \
INIT_SETUP(initsetup_align) \
INIT_CALLS \
CON_INITCALL \
SECURITY_INITCALL \
INIT_RAM_FS \
}
#define BSS_SECTION(sbss_align, bss_align) \
SBSS \
BSS(bss_align) \
. = ALIGN(4); \
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