Impact: less contention when issuing invalidate IPI, cleanup
Make x86_32 use the same tlb code as 64bit. The 64bit code uses
multiple IPI vectors for tlb shootdown to reduce contention. This
patch makes x86_32 allocate the same 8 IPIs as x86_64 and share the
code paths.
Note that the usage of asmlinkage is inconsistent for x86_32 and 64
and calls for further cleanup. This has been noted with a FIXME
comment in tlb_64.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
* 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (63 commits)
stacktrace: provide save_stack_trace_tsk() weak alias
rcu: provide RCU options on non-preempt architectures too
printk: fix discarding message when recursion_bug
futex: clean up futex_(un)lock_pi fault handling
"Tree RCU": scalable classic RCU implementation
futex: rename field in futex_q to clarify single waiter semantics
x86/swiotlb: add default swiotlb_arch_range_needs_mapping
x86/swiotlb: add default phys<->bus conversion
x86: unify pci iommu setup and allow swiotlb to compile for 32 bit
x86: add swiotlb allocation functions
swiotlb: consolidate swiotlb info message printing
swiotlb: support bouncing of HighMem pages
swiotlb: factor out copy to/from device
swiotlb: add arch hook to force mapping
swiotlb: allow architectures to override phys<->bus<->phys conversions
swiotlb: add comment where we handle the overflow of a dma mask on 32 bit
rcu: fix rcutorture behavior during reboot
resources: skip sanity check of busy resources
swiotlb: move some definitions to header
swiotlb: allow architectures to override swiotlb pool allocation
...
Fix up trivial conflicts in
arch/x86/kernel/Makefile
arch/x86/mm/init_32.c
include/linux/hardirq.h
as per Ingo's suggestions.
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (241 commits)
sched, trace: update trace_sched_wakeup()
tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3
Revert "x86: disable X86_PTRACE_BTS"
ring-buffer: prevent false positive warning
ring-buffer: fix dangling commit race
ftrace: enable format arguments checking
x86, bts: memory accounting
x86, bts: add fork and exit handling
ftrace: introduce tracing_reset_online_cpus() helper
tracing: fix warnings in kernel/trace/trace_sched_switch.c
tracing: fix warning in kernel/trace/trace.c
tracing/ring-buffer: remove unused ring_buffer size
trace: fix task state printout
ftrace: add not to regex on filtering functions
trace: better use of stack_trace_enabled for boot up code
trace: add a way to enable or disable the stack tracer
x86: entry_64 - introduce FTRACE_ frame macro v2
tracing/ftrace: add the printk-msg-only option
tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()
x86, bts: correctly report invalid bts records
...
Fixed up trivial conflict in scripts/recordmcount.pl due to SH bits
being already partly merged by the SH merge.
swiotlb on 32 bit will be used by Xen domain 0 support.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: trace more functions
When the function graph tracer is configured, three more files are not
traced to prevent only four functions to be traced. And this impacts the
normal function tracer too.
arch/x86/kernel/process_64/32.c:
I had crashes when I let this file traced. After some debugging, I saw
that the "current" task point was changed inside__swtich_to(), ie:
"write_pda(pcurrent, next_p);" inside process_64.c Since the tracer store
the original return address of the function inside current, we had
crashes. Only __switch_to() has to be excluded from tracing.
kernel/module.c and kernel/extable.c:
Because of a function used internally by the function graph tracer:
__kernel_text_address()
To let the other functions inside these files to be traced, this patch
introduces the __notrace_funcgraph function prefix which is __notrace if
function graph tracer is configured and nothing if not.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge x86/dumpstack into tracing/ftrace because upcoming ftrace changes
depend on cleanups already in x86/dumpstack.
Also merge to latest upstream -rc.
Impact: extend and enable the function graph tracer to 64-bit x86
This patch implements the support for function graph tracer under x86-64.
Both static and dynamic tracing are supported.
This causes some small CPP conditional asm on arch/x86/kernel/ftrace.c I
wanted to use probe_kernel_read/write to make the return address
saving/patching code more generic but it causes tracing recursion.
That would be perhaps useful to implement a notrace version of these
function for other archs ports.
Note that arch/x86/process_64.c is not traced, as in X86-32. I first
thought __switch_to() was responsible of crashes during tracing because I
believed current task were changed inside but that's actually not the
case (actually yes, but not the "current" pointer).
So I will have to investigate to find the functions that harm here, to
enable tracing of the other functions inside (but there is no issue at
this time, while process_64.c stays out of -pg flags).
A little possible race condition is fixed inside this patch too. When the
tracer allocate a return stack dynamically, the current depth is not
initialized before but after. An interrupt could occur at this time and,
after seeing that the return stack is allocated, the tracer could try to
trace it with a random uninitialized depth. It's a prevention, even if I
hadn't problems with it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
This patch changes the name of the "return function tracer" into
function-graph-tracer which is a more suitable name for a tracing
which makes one able to retrieve the ordered call stack during
the code flow.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Move the CONFIG guard from the .c file into the makefile.
Reported-by: Andi Kleen <andi-suse@firstfloor.org>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: add infrastructure for function-return tracing
Add low level support for ftrace return tracing.
This plug-in stores return addresses on the thread_info structure of
the current task.
The index of the current return address is initialized when the task
is the first one (init) and when a process forks (the child). It is
not needed when a task does a sys_execve because after this syscall,
it still needs to return on the kernel functions it called.
Note that the code of return_to_handler has been suggested by Steven
Rostedt as almost all of the ideas of improvements in this V3.
For purpose of security, arch/x86/kernel/process_32.c is not traced
because __switch_to() changes the current task during its execution.
That could cause inconsistency in the stored return address of this
function even if I didn't have any crash after testing with tracing on
this function enabled.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: do not do function-tracing in the early-printk code
this is useful when earlyprintk=vga,keep is used to debug tracer
plugins.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
As promised, now that dumpstack_32 and dumpstack_64 have so many bits
in common, we should merge the in-sync bits into a common file, to
prevent them from diverging again.
This patch removes bits which are common between dumpstack_32.c and
dumpstack_64.c and places them in a common dumpstack.c which is built
for both 32 and 64 bit arches.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Makefile | 2
arch/x86/kernel/Makefile | 2
arch/x86/kernel/Makefile | 2
arch/x86/kernel/Makefile | 2
arch/x86/kernel/Makefile | 2
arch/x86/kernel/Makefile | 2
arch/x86/kernel/dumpstack.c | 319 +++++++++++++++++++++++++++++++++++++++++
arch/x86/kernel/dumpstack.h | 39 +++++
arch/x86/kernel/dumpstack_32.c | 294 -------------------------------------
arch/x86/kernel/dumpstack_64.c | 285 ------------------------------------
5 files changed, 363 insertions(+), 576 deletions(-)
Impact: cleanup
now that the code is moved and converted to a work queue,
there's some minor cleanups that can be done.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
The corruption check code is rather sizable and it's likely to grow over
time when we add checks for more types of corruptions (there's a few
candidates in kerneloops.org that I want to add checks for)... so lets move
it to its own file
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The entire file of ftrace.c in the arch code needs to be marked
as notrace. It is much cleaner to do this from the Makefile with
CFLAGS_REMOVE_ftrace.o.
[ powerpc already had this in its Makefile. ]
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER. The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.
This patch was generated mostly by script, and partially by hand.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
show_interrupts() and proc helpers are basically the same for
32 and 64 bit. Move them to a shared source file.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Create /sys/firmware/sgi_uv sysfs entries for partition_id and coherence_id.
Signed-off-by: Russ Anderson <rja@sgi.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Provide a means for UV interrupt MMRs to be setup with the message to be sent
when an MSI is raised.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
traps_32.c and traps_64.c are now equal. Move one to traps.c,
delete the other one and change the Makefile
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The dumpstack code is logically quite independent from the
hardware traps. Split it out into its own file.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The dumpstack code is logically quite independent from the
hardware traps. Split it out into its own file.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Combine both generic and arch-specific parts of microcode into a
single module (arch-specific parts are config-dependent).
Also while we are at it, move arch-specific parts from microcode.h
into their respective arch-specific .c files.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: "Peter Oruba" <peter.oruba@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Enables xsave/xrstor by turning on cr4.osxsave on cpu's which have
the xsave support. For now, features that OS supports/enabled are
FP and SSE.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch introduces microcode patch loading for AMD
processors. It is based on previous corresponding work
for Intel processors.
It hooks into the general patch loading module. Main
difference is that a container file format is used to hold
all patch data for multiple processors as well as an
equivalent CPU table, which comes seperately, as opposed
to Intel's microcode patching solution.
Kconfig and Makefile have been changed provice config
and build option for new source file.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Refactored code by introducing a two-module solution.
There is one general module in which vendor specific modules can hook into.
However, that is exclusive, there is only one vendor specific module
allowed at a time. A CPU vendor check makes sure only the correct
module for the underlying system gets called.
Functinally in terms of patch loading itself there are no changes. This
refactoring provides a basis for future implementations of other vendors'
patch loaders.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Split off existing code into two seperate files. One file holds general
code, the other file vendor specific parts.
No functional changes, only refactoring.
Temporarily Introduced a new module name 'ucode' for result,
due to already taken name 'microcode'.
Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
ftrace requires certain low-level code, like spinlocks and timestamps,
to be compiled without -pg in order to avoid infinite recursion. This
patch splits out the core paravirt spinlocks and the Xen spinlocks
into separate files which can be compiled without -pg.
Also do xen/time.c while we're about it. As a result, we can now use
ftrace within a Xen domain.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Real-time code needs to know the number of cycles per second
on SGI UV. The information is provided via a run time BIOS
call. This patch provides the linux side of that interface.
This is the first of several run time BIOS calls to be defined
in uv/bios.h and bios_uv.c.
Note that BIOS_CALL() is just a stub for now. The bios
side is being worked on.
Signed-off-by: Russ Anderson <rja@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
-tip testing found a bootup hang here:
initcall anon_inode_init+0x0/0x130 returned 0 after 0 msecs
calling acpi_event_init+0x0/0x57
the bootup should have continued with:
initcall acpi_event_init+0x0/0x57 returned 0 after 45 msecs
but it hung hard there instead.
bisection led to this commit:
| commit 5806b81ac1
| Merge: d14c8a6... 6712e29...
| Author: Ingo Molnar <mingo@elte.hu>
| Date: Mon Jul 14 16:11:52 2008 +0200
| Merge branch 'auto-ftrace-next' into tracing/for-linus
turns out that i made this mistake in the merge:
ifdef CONFIG_FTRACE
# Do not profile debug utilities
CFLAGS_REMOVE_tsc_64.o = -pg
CFLAGS_REMOVE_tsc_32.o = -pg
those two files got unified meanwhile - so the dont-profile annotation
got lost. The proper rule is:
CFLAGS_REMOVE_tsc.o = -pg
i guess this could have been caught sooner if the CFLAGS_REMOVE* kbuild
rule aborted the build if it met a target that does not exist anymore?
Signed-off-by: Ingo Molnar <mingo@elte.hu>
the paravirt-spinlock patches caused a boot hang with this config:
http://redhat.com/~mingo/misc/config-Wed_Jul__9_14_47_04_CEST_2008.bad
i have bisected it down to:
| commit e17b58c2e85bc2ad2afc07fb8d898017c2b75ed1
| Author: Jeremy Fitzhardinge <jeremy@goop.org>
| Date: Mon Jul 7 12:07:53 2008 -0700
|
| xen: implement Xen-specific spinlocks
i.e. applying that patch alone causes the hang. The hang happens in the
ftrace self-test:
initcall utsname_sysctl_init+0x0/0x19 returned 0 after 0 msecs
calling init_sched_switch_trace+0x0/0x4c
Testing tracer sched_switch: PASSED
initcall init_sched_switch_trace+0x0/0x4c returned 0 after 167 msecs
calling init_function_trace+0x0/0x12
Testing tracer ftrace:
[hard hang]
it should have continued like this:
Testing tracer ftrace: PASSED
initcall init_function_trace+0x0/0x12 returned 0 after 198 msecs
calling init_irqsoff_tracer+0x0/0x14
Testing tracer irqsoff: PASSED
initcall init_irqsoff_tracer+0x0/0x14 returned 0 after 3 msecs
calling init_mmio_trace+0x0/0x12
initcall init_mmio_trace+0x0/0x12 returned 0 after 0 msecs
the problem is that such lowlevel primitives as spinlocks should never
be built with -pg (which ftrace does). Marking paravirt.o as non-pg and
marking all spinlock ops as always-inline solve the hang.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Yinghai Lu reported crashes on 64-bit x86:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
IP: [<ffffffff80253b17>] hrtick_start_fair+0x89/0x173
[...]
And with a long session of debugging and a lot of difficulty, tracked it down
to this commit:
--------------->
8fbbc4b45c is first bad commit
commit 8fbbc4b45c
Author: Alok Kataria <akataria@vmware.com>
Date: Tue Jul 1 11:43:34 2008 -0700
x86: merge tsc_init and clocksource code
<--------------
The problem is that the TSC unification missed these Makefile rules
in arch/x86/kernel/Makefile:
# Do not profile debug and lowlevel utilities
CFLAGS_REMOVE_tsc_64.o = -pg
CFLAGS_REMOVE_tsc_32.o = -pg
...
CFLAGS_tsc_64.o := $(nostackp)
...
which rules make sure that various instrumentation and debugging
facilities are disabled for code that might end up in a VDSO - such as
the TSC code.
Reported-and-bisected-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Conflicts:
Signed-off-by: Ingo Molnar <mingo@elte.hu>
this is the big move: flip over VISWS to generic arch support.
From this commit on CONFIG_X86_VISWS is just another (default-disabled)
option that turns on certain quirks - no other complications.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Unify the clocksource code.
Unify the tsc_init code.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Dan Hecht <dhecht@vmware.com>
Cc: Dan Hecht <dhecht@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move the basic global variable definitions and sched_clock handling in the
common "tsc.c" file.
- Unify notsc kernel command line handling for 32 bit and 64bit.
- Functional changes for 64bit.
- "tsc_disabled" is updated if "notsc" is passed at boottime.
- Fallback to jiffies for sched_clock, incase notsc is passed on
commandline.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Dan Hecht <dhecht@vmware.com>
Cc: Dan Hecht <dhecht@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
and let 64 bit use that instead of setup_64.c
[ mingo@elte.hu ]
x86: build fix
fix:
arch/x86/kernel/setup.c: In function ‘setup_arch':
arch/x86/kernel/setup.c:561: error: implicit declaration of function ‘efi_reserve_early'
and:
arch/x86/kernel/setup.c:766: error: implicit declaration of function 'init_cpu_to_node'
and:
arch/x86/kernel/setup.c:676: warning: operation on 'max_pfn_mapped' may be undefined
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
some functions need to be moved to setup_numa.c
after we merge setup32/64.c, some funcs need to be moved back to setup.c
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
TLB shootdown for SGI UV.
Depends on patch (in tip/x86/irq):
x86-update-macros-used-by-uv-platform.patch Jack Steiner May 29
This patch provides the ability to flush TLB's in cpu's that are not on
the local node. The hardware mechanism for distributing the flush
messages is the UV's "broadcast assist unit".
The hook to intercept TLB shootdown requests is a 2-line change to
native_flush_tlb_others() (arch/x86/kernel/tlb_64.c).
This code has been tested on a hardware simulator. The real hardware
is not yet available.
The shootdown statistics are provided through /proc/sgi_uv/ptc_statistics.
The use of /sys was considered, but would have required the use of
many /sys files. The debugfs was also considered, but these statistics
should be available on an ongoing basis, not just for debugging.
Issues to be fixed later:
- The IRQ for the messaging interrupt is currently hardcoded as 200
(see UV_BAU_MESSAGE). It should be dynamically assigned in the future.
- The use of appropriate udelay()'s is untested, as they are a problem
in the simulator.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds structs for the paravirt clocksource ABI
used by both xen and kvm (pvclock-abi.h).
It also adds some helper functions to read system time and
wall clock time from a paravirtual clocksource (pvclock.[ch]).
They are based on the xen code. They are enabled using
CONFIG_PARAVIRT_CLOCK.
Subsequent patches of this series will put the code in use.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch extracts the common part of head32.c and head64.c into head.c.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: andi@firstfloor.org
Cc: mingo@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
It looks good to move bugs_64.c to cpu/bugs_64.c.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
on paravirt enabled 64-bit kernels the paravirt ops do function
calls themselves - which is bad with the stackprotector - for
example pda_init() loads 0 into %gs and then does MSR_GS_BASE
write (which modifies gs.base) - but that MSR write is a function
call on paravirt, which with stackprotector tries to read the
stack canary from the PDA ... crashing the bootup.
the solution was suggested by Arjan van de Ven: to exclude paravirt.c
from stackprotector, too many lowlevel functionality is in it. It's
not like we'll have paravirt functions with character arrays on
their stack anyway...
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>
The leftovers of the i8259 unification have nothing to do with i8259
at all. They contain interrupt init code and the i8259_xx name is just
misleading now.
Rename them to irqinit_32/64.c
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Make conversion of i8259 very mechanical -- i8259 was generated by
diff -D, with too different parts left in i8259_32 and
i8259_64.c. Only "by hand" changes were removal of #ifdef from middle
of the comment (prevented compilation) and removal of one static to
allow splitting into files.
Of course, it will need some cleanups now, and those will follow.
Signed-of-by: Pavel Machek <pavel@suse.cz>
The leftovers of the i8259 unification have nothing to do with i8259
at all. They contain interrupt init code and the i8259_xx name is just
misleading now.
Rename them to initirq_32/64.c
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch removes the Makefile turd and uses the nice CFLAGS_REMOVE macro
in the x86/kernel directory.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds a feature to dynamically replace the ftrace code
with the jmps to allow a kernel with ftrace configured to run
as fast as it can without it configured.
The way this works, is on bootup (if ftrace is enabled), a ftrace
function is registered to record the instruction pointer of all
places that call the function.
Later, if there's still any code to patch, a kthread is awoken
(rate limited to at most once a second) that performs a stop_machine,
and replaces all the code that was called with a jmp over the call
to ftrace. It only replaces what was found the previous time. Typically
the system reaches equilibrium quickly after bootup and there's no code
patching needed at all.
e.g.
call ftrace /* 5 bytes */
is replaced with
jmp 3f /* jmp is 2 bytes and we jump 3 forward */
3:
When we want to enable ftrace for function tracing, the IP recording
is removed, and stop_machine is called again to replace all the locations
of that were recorded back to the call of ftrace. When it is disabled,
we replace the code back to the jmp.
Allocation is done by the kthread. If the ftrace recording function is
called, and we don't have any record slots available, then we simply
skip that call. Once a second a new page (if needed) is allocated for
recording new ftrace function calls. A large batch is allocated at
boot up to get most of the calls there.
Because we do this via stop_machine, we don't have to worry about another
CPU executing a ftrace call as we modify it. But we do need to worry
about NMI's so all functions that might be called via nmi must be
annotated with notrace_nmi. When this code is configured in, the NMI code
will not call notrace.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
fix pcspkr dependancies: make the pcspkr platform
drivers to depend on a platform device, and
not the other way around.
Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
CC: Vojtech Pavlik <vojtech@suse.cz>
CC: Michael Opdenacker <michael-lists@free-electrons.com>
[fixed for 2.6.26-rc1 by tiwai]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
the 'reboot_force' flag is a notion that non-PC subarchitectures do
not have.
also, unify the X86_BIOS_REBOOT option between 32-bit and 64-bit
and get rid of a few unnecessary Kconfig and Makefile complications
that way.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-bigbox-pci:
x86: add pci=check_enable_amd_mmconf and dmi check
x86: work around io allocation overlap of HT links
acpi: get boot_cpu_id as early for k8_scan_nodes
x86_64: don't need set default res if only have one root bus
x86: double check the multi root bus with fam10h mmconf
x86: multi pci root bus with different io resource range, on 64-bit
x86: use bus conf in NB conf fun1 to get bus range on, on 64-bit
x86: get mp_bus_to_node early
x86 pci: remove checking type for mmconfig probe
x86: remove unneeded check in mmconf reject
driver core: try parent numa_node at first before using default
x86: seperate mmconf for fam10h out from setup_64.c
x86: if acpi=off, force setting the mmconf for fam10h
x86_64: check MSR to get MMCONFIG for AMD Family 10h
x86_64: check and enable MMCONFIG for AMD Family 10h
x86_64: set cfg_size for AMD Family 10h in case MMCONFIG
x86: mmconf enable mcfg early
x86: clear pci_mmcfg_virt when mmcfg get rejected
x86: validate against acpi motherboard resources
Fixed up fairly trivial conflicts in arch/x86/pci/{init.c,pci.h} due to
OLPC support manually.
This adds support for OLPC XO hardware. Open Firmware on XOs don't contain
the VSA, so it is necessary to emulate the PCI BARs in the kernel. This also
adds functionality for running EC commands, and a CONFIG_OLPC.
A number of OLPC drivers depend upon CONFIG_OLPC.
olpc_ec_timeout is a hack to work around Embedded Controller bugs.
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: geode_has_vsa build fix]
[akpm@linux-foundation.org: olpc_register_battery_callback doesn't exist]
Signed-off-by: Andres Salomon <dilinger@debian.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the guest part of kvm clock implementation
It does not do tsc-only timing, as tsc can have deltas
between cpus, and it did not seem worthy to me to keep
adjusting them.
We do use it, however, for fine-grained adjustment.
Other than that, time comes from the host.
[randy dunlap: add missing include]
[randy dunlap: disallow on Voyager or Visual WS]
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
