Commit Graph

73 Commits

Author SHA1 Message Date
Andrey Ryabinin
196bd485ee x86/asm: Use register variable to get stack pointer value
Currently we use current_stack_pointer() function to get the value
of the stack pointer register. Since commit:

  f5caf621ee ("x86/asm: Fix inline asm call constraints for Clang")

... we have a stack register variable declared. It can be used instead of
current_stack_pointer() function which allows to optimize away some
excessive "mov %rsp, %<dst>" instructions:

 -mov    %rsp,%rdx
 -sub    %rdx,%rax
 -cmp    $0x3fff,%rax
 -ja     ffffffff810722fd <ist_begin_non_atomic+0x2d>

 +sub    %rsp,%rax
 +cmp    $0x3fff,%rax
 +ja     ffffffff810722fa <ist_begin_non_atomic+0x2a>

Remove current_stack_pointer(), rename __asm_call_sp to current_stack_pointer
and use it instead of the removed function.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170929141537.29167-1-aryabinin@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-29 19:39:44 +02:00
Paul Gortmaker
186f43608a x86/kernel: Audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.  Build testing
revealed some implicit header usage that was fixed up accordingly.

Note that some bool/obj-y instances remain since module.h is
the header for some exception table entry stuff, and for things
like __init_or_module (code that is tossed when MODULES=n).

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160714001901.31603-4-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 15:06:41 +02:00
Linus Torvalds
aca9c293d0 x86: fix up a few misc stack pointer vs thread_info confusions
As the actual pointer value is the same for the thread stack allocation
and the thread_info, code that confused the two worked fine, but will
break when the thread info is moved away from the stack allocation.  It
also looks very confusing.

For example, the kprobe code wanted to know the current top of stack.
To do that, it used this:

	(unsigned long)current_thread_info() + THREAD_SIZE

which did indeed give the correct value.  But it's not only a fairly
nonsensical expression, it's also rather complex, especially since we
actually have this:

	static inline unsigned long current_top_of_stack(void)

which not only gives us the value we are interested in, but happens to
be how "current_thread_info()" is currently defined as:

	(struct thread_info *)(current_top_of_stack() - THREAD_SIZE);

so using current_thread_info() to figure out the top of the stack really
is a very round-about thing to do.

The other cases are just simpler confusion about task_thread_info() vs
task_stack_page(), which currently return the same pointer - but if you
want the stack page, you really should be using the latter one.

And there was one entirely unused assignment of the current stack to a
thread_info pointer.

All cleaned up to make more sense today, and make it easier to move the
thread_info away from the stack in the future.

No semantic changes.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-24 16:55:53 -07:00
Thomas Gleixner
bd0b9ac405 genirq: Remove irq argument from irq flow handlers
Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the argument.

Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
2015-09-16 15:47:51 +02:00
Thomas Gleixner
a47d4576cd x86/irq: Do not dereference irq descriptor before checking it
Having the IS_NULL_OR_ERR() check after dereferencing the pointer is
not really working well.

Move the dereference after the check.

Fixes: a782a7e46b 'x86/irq: Store irq descriptor in vector array'
Reported-and-tested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-28 10:30:15 +02:00
Thomas Gleixner
a782a7e46b x86/irq: Store irq descriptor in vector array
We can spare the irq_desc lookup in the interrupt entry code if we
store the descriptor pointer in the vector array instead the interrupt
number.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/20150802203609.717724106@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-06 00:14:59 +02:00
Brian Gerst
c5bde906d2 x86/irq: Merge irq_regs & irq_stat
Move irq_regs and irq_stat definitions to irq.c.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1431185813-15413-2-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-10 12:34:27 +02:00
Andy Lutomirski
f39b6f0ef8 x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'
user_mode_vm() and user_mode() are now the same.  Change all callers
of user_mode_vm() to user_mode().

The next patch will remove the definition of user_mode_vm.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org
[ Merged to a more recent kernel. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-23 11:14:17 +01:00
Andy Lutomirski
83653c16da x86: Clean up current_stack_pointer
There's no good reason for it to be a macro, and x86_64 will want to
use it, so it should be in a header.

Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2015-01-02 10:22:46 -08:00
Mathias Krause
6cce16f99d x86, threadinfo: Redo "x86: Use inline assembler to get sp"
This patch restores the changes of commit dff38e3e93 "x86: Use inline
assembler instead of global register variable to get sp". They got lost
in commit 198d208df4 "x86: Keep thread_info on thread stack in x86_32"
while moving the code to arch/x86/kernel/irq_32.c.

Quoting Andi from commit dff38e3e93:

"""
LTO in gcc 4.6/47. has trouble with global register variables. They were
used to read the stack pointer. Use a simple inline assembler statement
with a mov instead.

This also helps LLVM/clang, which does not support global register
variables.
"""

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Link: http://lkml.kernel.org/r/1394178752-18047-1-git-send-email-minipli@googlemail.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-10 17:32:01 -07:00
Steven Rostedt
198d208df4 x86: Keep thread_info on thread stack in x86_32
x86_64 uses a per_cpu variable kernel_stack to always point to
the thread stack of current. This is where the thread_info is stored
and is accessed from this location even when the irq or exception stack
is in use. This removes the complexity of having to maintain the
thread info on the stack when interrupts are running and having to
copy the preempt_count and other fields to the interrupt stack.

x86_32 uses the old method of copying the thread_info from the thread
stack to the exception stack just before executing the exception.

Having the two different requires #ifdefs and also the x86_32 way
is a bit of a pain to maintain. By converting x86_32 to the same
method of x86_64, we can remove #ifdefs, clean up the x86_32 code
a little, and remove the overhead of the copy.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20110806012354.263834829@goodmis.org
Link: http://lkml.kernel.org/r/20140206144321.852942014@goodmis.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-06 16:56:55 -08:00
Steven Rostedt
0788aa6a23 x86: Prepare removal of previous_esp from i386 thread_info structure
The i386 thread_info contains a previous_esp field that is used
to daisy chain the different stacks for dump_stack()
(ie. irq, softirq, thread stacks).

The goal is to eventual make i386 handling of thread_info the same
as x86_64, which means that the thread_info will not be in the stack
but as a per_cpu variable. We will no longer depend on thread_info
being able to daisy chain different stacks as it will only exist
in one location (the thread stack).

By moving previous_esp to the end of thread_info and referencing
it as an offset instead of using a thread_info field, this becomes
a stepping stone to moving the thread_info.

The offset to get to the previous stack is rather ugly in this
patch, but this is only temporary and the prev_esp will be changed
in the next commit. This commit is more for sanity checks of the
change.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Robert Richter <rric@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20110806012353.891757693@goodmis.org
Link: http://lkml.kernel.org/r/20140206144321.608754481@goodmis.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-06 16:56:54 -08:00
Linus Torvalds
39cf275a1a Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler changes from Ingo Molnar:
 "The main changes in this cycle are:

   - (much) improved CONFIG_NUMA_BALANCING support from Mel Gorman, Rik
     van Riel, Peter Zijlstra et al.  Yay!

   - optimize preemption counter handling: merge the NEED_RESCHED flag
     into the preempt_count variable, by Peter Zijlstra.

   - wait.h fixes and code reorganization from Peter Zijlstra

   - cfs_bandwidth fixes from Ben Segall

   - SMP load-balancer cleanups from Peter Zijstra

   - idle balancer improvements from Jason Low

   - other fixes and cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
  ftrace, sched: Add TRACE_FLAG_PREEMPT_RESCHED
  stop_machine: Fix race between stop_two_cpus() and stop_cpus()
  sched: Remove unnecessary iteration over sched domains to update nr_busy_cpus
  sched: Fix asymmetric scheduling for POWER7
  sched: Move completion code from core.c to completion.c
  sched: Move wait code from core.c to wait.c
  sched: Move wait.c into kernel/sched/
  sched/wait: Fix __wait_event_interruptible_lock_irq_timeout()
  sched: Avoid throttle_cfs_rq() racing with period_timer stopping
  sched: Guarantee new group-entities always have weight
  sched: Fix hrtimer_cancel()/rq->lock deadlock
  sched: Fix cfs_bandwidth misuse of hrtimer_expires_remaining
  sched: Fix race on toggling cfs_bandwidth_used
  sched: Remove extra put_online_cpus() inside sched_setaffinity()
  sched/rt: Fix task_tick_rt() comment
  sched/wait: Fix build breakage
  sched/wait: Introduce prepare_to_wait_event()
  sched/wait: Add ___wait_cond_timeout() to wait_event*_timeout() too
  sched: Remove get_online_cpus() usage
  sched: Fix race in migrate_swap_stop()
  ...
2013-11-12 10:20:12 +09:00
Frederic Weisbecker
7d65f4a655 irq: Consolidate do_softirq() arch overriden implementations
All arch overriden implementations of do_softirq() share the following
common code: disable irqs (to avoid races with the pending check),
check if there are softirqs pending, then execute __do_softirq() on
a specific stack.

Consolidate the common parts such that archs only worry about the
stack switch.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
2013-10-01 12:53:25 +02:00
Peter Zijlstra
c2daa3bed5 sched, x86: Provide a per-cpu preempt_count implementation
Convert x86 to use a per-cpu preemption count. The reason for doing so
is that accessing per-cpu variables is a lot cheaper than accessing
thread_info variables.

We still need to save/restore the actual preemption count due to
PREEMPT_ACTIVE so we place the per-cpu __preempt_count variable in the
same cache-line as the other hot __switch_to() variables such as
current_task.

NOTE: this save/restore is required even for !PREEMPT kernels as
cond_resched() also relies on preempt_count's PREEMPT_ACTIVE to ignore
task_struct::state.

Also rename thread_info::preempt_count to ensure nobody is
'accidentally' still poking at it.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-gzn5rfsf8trgjoqx8hyayy3q@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25 14:07:57 +02:00
Paul Gortmaker
148f9bb877 x86: delete __cpuinit usage from all x86 files
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/x86 uses of the __cpuinit macros from
all C files.  x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:56 -04:00
Thomas Gleixner
38e7c572ce x86: Use common threadinfo allocator
The only difference is the free_thread_info function, which frees
xstate.

Use the new arch_release_task_struct() function instead and switch
over to the core allocator.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120505150141.559556763@linutronix.de
Cc: x86@kernel.org
2012-05-08 14:08:44 +02:00
Linus Torvalds
986cb48c5a x86-32/irq: Don't switch to irq stack for a user-mode irq
If the irq happens in user mode, our kernel stack is empty
(apart from the pt_regs themselves, of course), so there's no
need or advantage to switch.

And it really doesn't save any stack space, quite the reverse:
it means that a nested interrupt cannot switch irq stacks. So
instead of saving kernel stack space, it actually causes the
potential for *more* stack usage.

Also simplify the preemption count copy when we do switch
stacks: just copy the whole preemption count, rather than just
the softirq parts of it.  There is no advantage to the partial
copy: it is more effort to get a less correct result.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202191139260.10000@i5.linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-20 09:30:18 +01:00
Ingo Molnar
53b5650273 x86: Fix the 32-bit stackoverflow-debug build
The panic_on_stackoverflow variable needs to be avilable
on the 32-bit side as well ...

Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20111129060836.11076.12323.stgit@ltc219.sdl.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 12:25:44 +01:00
Mitsuo Hayasaka
55af77969f x86: Panic on detection of stack overflow
Currently, messages are just output on the detection of stack
overflow, which is not sufficient for systems that need a
high reliability. This is because in general the overflow may
corrupt data, and the additional corruption may occur due to
reading them unless systems stop.

This patch adds the sysctl parameter
kernel.panic_on_stackoverflow and causes a panic when detecting
the overflows of kernel, IRQ and exception stacks except user
stack according to the parameter. It is disabled by default.

Signed-off-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: yrl.pp-manager.tt@hitachi.com
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20111129060836.11076.12323.stgit@ltc219.sdl.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 11:37:47 +01:00
Lucas De Marchi
0d2eb44f63 x86: Fix common misspellings
They were generated by 'codespell' and then manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: trivial@kernel.org
LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-18 10:39:30 +01:00
Linus Torvalds
404cbbd52f Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Clear irqstack thread_info
  x86: Make relocatable kernel work with new binutils
2011-01-18 14:29:21 -08:00
Brian Gerst
7b698ea377 x86: Clear irqstack thread_info
Mathias Merz reported that v2.6.37 failed to boot on his
system.

Make sure that the thread_info part of the irqstack is
initialized to zeroes.

Reported-and-Tested-by: Matthias Merz <linux@merz-ka.de>
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <AANLkTimyKXfJ1x8tgwrr1hYnNLrPfgE1NTe4z7L6tUDm@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-18 14:58:37 +01:00
Tejun Heo
0a3aee0da4 x86: Use this_cpu_ops to optimize code
Go through x86 code and replace __get_cpu_var and get_cpu_var
instances that refer to a scalar and are not used for address
determinations.

Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2010-12-30 12:20:28 +01:00
Eric Dumazet
5c1eb08936 x86-32: Restore irq stacks NUMA-aware allocations
Commit 22d4cd4c4d ("Allocate irq stacks seperate from percpu
area") removed NUMA affinity of IRQ stacks as side-effect of
the fix.

Using alloc_pages_node() instead of __get_free_pages() is safe,
even if the target node has no available LOWMEM pages :
alloc_pages_node() fallbacks to another node.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Brian Gerst <brgerst@gmail.com>
Cc: tj@kernel.org
Cc: torvalds@linux-foundation.org
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1288276854.2649.607.camel@edumazet-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-29 08:17:07 +02:00
Brian Gerst
22d4cd4c4d x86-32: Allocate irq stacks seperate from percpu area
The percpu allocator cannot handle alignments larger than one
page. Allocate the irq stacks seperately, and only keep the
pointers as percpu data.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tj@kernel.org
LKML-Reference: <1288158182-1753-1-git-send-email-brgerst@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-27 17:31:42 +02:00
Alexander van Heukelum
fe8e0c25ca x86, 32-bit: Align percpu area and irq stacks to THREAD_SIZE
The irq stacks, located in the percpu-area, need to be
THREAD_SIZE aligned. Add the infrastucture to align percpu
variables to larger-than-pagesize amounts within the percpu
area, and use it to specify the alignment for the irq stacks.
Also align the percpu area itself to THREAD_SIZE.

This should make irq stacks work with 8K THREAD_SIZE.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Cc: Tejun Heo <tj@kernel.org>
Cc: hch@lst.de
LKML-Reference: <1283799222.15941.1393621887@webmail.messagingengine.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-07 05:07:00 +02:00
Christoph Hellwig
2589737429 x86-32: Align IRQ stacks properly
As suggested by Steven Rostedt we need to align the IRQ stacks to the
stack size, not just the page size to make them work for stack traces
and other things that depend on finding the stack slot itself with 8k
stacks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
LKML-Reference: <20100727121313.GA19976@lst.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-07-27 10:06:54 -07:00
Christoph Hellwig
7974891db2 x86: Always use irq stacks
IRQ stacks provide much better safety against unexpected stack use from
interrupts, at the minimal downside of slightly higher memory usage.
Enable irq stacks also for the default 8k stack on 32-bit kernels to
minimize the problem of stack overflows through interrupt activity.

This is what the 64-bit kernel and various other architectures already do.

Signed-off-by: Christoph Hellwig <hch@lst.de>
LKML-Reference: <20100628121554.GA6605@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-06-29 12:12:59 +02:00
Suresh Siddha
7a7732bc0f x86: Unify fixup_irqs() for 32-bit and 64-bit kernels
There is no reason to have different fixup_irqs() for 32-bit and
64-bit kernels. Unify by using the superior 64-bit version for
both the kernels.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
LKML-Reference: <20091026230001.562512739@sbs-t61.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-02 15:56:34 +01:00
Marcin Slusarz
9f51e24ee8 x86: Use printk_once()
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
LKML-Reference: <1249847649-11631-6-git-send-email-marcin.slusarz@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 22:28:34 +02:00
Ingo Molnar
0edcf8d692 Merge branch 'tj-percpu' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into core/percpu
Conflicts:
	arch/x86/include/asm/pgtable.h
2009-02-24 21:52:45 +01:00
Lai Jiangshan
42f8faecf7 x86: use percpu data for 4k hardirq and softirq stacks
Impact: economize memory for large NR_CPUS

percpu data is setup earlier than irq, we can use percpu data
to economize memory.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-02-20 16:26:10 +09:00
Ingo Molnar
e641f5f525 x86, apic: remove duplicate asm/apic.h inclusions
Impact: cleanup

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-17 17:52:44 +01:00
Ingo Molnar
7b6aa335ca x86, apic: remove genapic.h
Impact: cleanup

Remove genapic.h and remove all references to it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-17 17:52:44 +01:00
Jeremy Fitzhardinge
7c1d7cdcef x86: unify do_IRQ()
With the differences in interrupt handling hoisted into handle_irq(),
do_IRQ is more or less identical between 32 and 64 bit, so unify it.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-09 12:16:05 +01:00
Jeremy Fitzhardinge
9b2b76a334 x86: add handle_irq() to allow interrupt injection
Xen uses a different interrupt path, so introduce handle_irq() to
allow interrupts to be inserted into the normal interrupt path.  This
is handled slightly differently on 32 and 64-bit.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-09 12:15:57 +01:00
Ingo Molnar
1dcdd3d15e x86: remove mach_apic.h
Spread mach_apic.h definitions into genapic.h. (with some knock-on effects
on smp.h and apic.h.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-29 14:16:42 +01:00
Mike Travis
7f7ace0cda cpumask: update irq_desc to use cpumask_var_t
Impact: reduce memory usage, use new cpumask API.

Replace the affinity and pending_masks with cpumask_var_t's.  This adds
to the significant size reduction done with the SPARSE_IRQS changes.

The added functions (init_alloc_desc_masks & init_copy_desc_masks) are
in the include file so they can be inlined (and optimized out for the
!CONFIG_CPUMASKS_OFFSTACK case.)  [Naming chosen to be consistent with
the other init*irq functions, as well as the backwards arg declaration
of "from, to" instead of the more common "to, from" standard.]

Includes a slight change to the declaration of struct irq_desc to embed
the pending_mask within ifdef(CONFIG_SMP) to be consistent with other
references, and some small changes to Xen.

Tested: sparse/non-sparse/cpumask_offstack/non-cpumask_offstack/nonuma/nosmp on x86_64

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: virtualization@lists.osdl.org
Cc: xen-devel@lists.xensource.com
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
2009-01-11 19:12:46 +01:00
Jaswinder Singh Rajput
72ade5f9ca x86: irq_32.c fix style problems
Impact: cleanup

Fix:

 WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
 ERROR: "(foo*)" should be "(foo *)"
 ERROR: space required after that ',' (ctx:VxV)

total: 5 errors, 1 warnings

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-04 18:19:37 +01:00
Mike Travis
d7b381bb7b x86: fixup_irqs() doesnt need an argument.
Impact: cleanup, remove on-stack cpumask.

The "map" arg is always cpu_online_mask.  Importantly, set_affinity
always ands the argument with cpu_online_mask anyway, so we don't need
to do it in fixup_irqs(), avoiding a temporary.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
2008-12-16 17:40:57 -08:00
Rusty Russell
968ea6d80e Merge ../linux-2.6-x86
Conflicts:

	arch/x86/kernel/io_apic.c
	kernel/sched.c
	kernel/sched_stats.h
2008-12-13 21:55:51 +10:30
Rusty Russell
0de26520c7 cpumask: make irq_set_affinity() take a const struct cpumask
Impact: change existing irq_chip API

Not much point with gentle transition here: the struct irq_chip's
setaffinity method signature needs to change.

Fortunately, not widely used code, but hits a few architectures.

Note: In irq_select_affinity() I save a temporary in by mangling
irq_desc[irq].affinity directly.  Ingo, does this break anything?

(Folded in fix from KOSAKI Motohiro)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: jeremy@xensource.com
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
2008-12-13 21:20:26 +10:30
Yinghai Lu
0b8f1efad3 sparse irq_desc[] array: core kernel and x86 changes
Impact: new feature

Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with
NR_CPUS set to large values. The goal is to be able to scale up to much
larger NR_IRQS value without impacting the (important) common case.

To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of
irq_desc pointers.

When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc,
this also makes the IRQ descriptors NUMA-local (to the site that calls
request_irq()).

This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now
uses desc->chip_data for x86 to store irq_cfg.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-08 14:31:51 +01:00
Thomas Gleixner
249f6d9eab x86: move ack_bad_irq() to irq.c
Share more duplicated code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16 16:53:30 +02:00
Thomas Gleixner
6b39ba771e x86: unify show_interrupts() and proc helpers
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>
2008-10-16 16:53:29 +02:00
Thomas Gleixner
c0c168ca26 x86: cleanup show_interrupts
The sparseirq patches introduced some more ugliness in show_interrupts().
Clean it up all together and make the code easier to read by splitting out
the "tail" function  which prints the special interrupts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16 16:53:29 +02:00
Thomas Gleixner
2cc21ef843 genirq: remove sparse irq code
This code is not ready, but we need to rip it out instead of rebasing
as we would lose the APIC/IO_APIC unification otherwise.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16 16:53:15 +02:00
Yinghai Lu
7564676813 x86: irq no should not use hex in /proc/interrupts
Arjan van de Ven noticed that we changed IRQ numbers from decimal
to hex in /proc/interrupts - that can break user-space utilities
like irqbalanced.

Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:53:12 +02:00
Yinghai Lu
8f09cd20a2 x86: make HAVE_SPARSE_IRQ support selectable
Ingo said sparse_irq is some intrusive. need to make it selectable

to make it simple, remove irq_desc as parameter in some functions.
(ack, eoi, set_affinity).
may need to make member if irq_chip to take irq_desc, or struct irq later.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:52:57 +02:00