There is nothing really arch specific of the push and pop functions
used by the function graph tracer. This patch moves them to generic
code.
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: bugfix
Considering the situation as follow:
before: mcelog.next == 1, mcelog.entry[0].finished = 1
+--------------------------------------------------------------------------
R W1 W2 W3
read mcelog.next (1)
mcelog.next++ (2)
(working on entry 1,
finished == 0)
mcelog.next = 0
mcelog.next++ (1)
(working on entry 0)
mcelog.next++ (2)
(working on entry 1)
<----------------- race ---------------->
(done on entry 1,
finished = 1)
(done on entry 1,
finished = 1)
To fix the race condition, a cmpxchg loop is added to mce_read() to
ensure no new MCE record can be added between mcelog.next reading and
mcelog.next = 0.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Lower priority bug fix
Offlined CPUs could still get machine checks, but the machine check handler
cannot handle them properly, leading to an unconditional crash. Disable
machine checks on CPUs that are going down.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: bug fix, in this case the resume handler shouldn't run which
avoids incorrectly reenabling machine checks on resume
When MCEs are completely disabled on the command line don't set
up the sysdev devices for them either.
Includes a comment fix from Thomas Gleixner.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Higher priority bug fix
The machine check poller runs a single timer and then broadcasted an
IPI to all CPUs to check them. This leads to unnecessary
synchronization between CPUs. The original CPU running the timer has
to wait potentially a long time for all other CPUs answering. This is
also real time unfriendly and in general inefficient.
This was especially a problem on systems with a lot of events where
the poller run with a higher frequency after processing some events.
There could be more and more CPU time wasted with this, to
the point of significantly slowing down machines.
The machine check polling is actually fully independent per CPU, so
there's no reason to not just do this all with per CPU timers. This
patch implements that.
Also switch the poller also to use standard timers instead of work
queues. It was using work queues to be able to execute a user program
on a event, but mce_notify_user() handles this case now with a
separate callback. So instead always run the poll code in in a
standard per CPU timer, which means that in the common case of not
having to execute a trigger there will be less overhead.
This allows to clean up the initialization significantly, because
standard timers are already up when machine checks get init'ed. No
multiple initialization functions.
Thanks to Thomas Gleixner for some help.
Cc: thockin@google.com
v2: Use del_timer_sync() on cpu shutdown and don't try to handle
migrated timers.
v3: Add WARN_ON for timer running on unexpected CPU
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Needed for bug fix in next patch
This relaxes the requirement that mce_notify_user has to run in process
context. Useful for future changes, but also leads to cleaner
behaviour now. Now instead mce_notify_user can be called directly
from interrupt (but not NMI) context.
The work queue only uses a single global work struct, which can be done safely
because it is always free to reuse before the trigger function is executed.
This way no events can be lost.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: low priority bug fix
This removes part of a a patch I added myself some time ago. After some
consideration the patch was a bad idea. In particular it stopped machine check
exceptions during code patching.
To quote the comment:
* MCEs only happen when something got corrupted and in this
* case we must do something about the corruption.
* Ignoring it is worse than a unlikely patching race.
* Also machine checks tend to be broadcast and if one CPU
* goes into machine check the others follow quickly, so we don't
* expect a machine check to cause undue problems during to code
* patching.
So undo the machine check related parts of
8f4e956b31 NMIs are still disabled.
This only removes code, the only additions are a new comment.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Bug fix
During suspend it is not reliable to process machine check
exceptions, because CPUs disappear but can still get machine check
broadcasts. Also the system is slightly more likely to
machine check them, but the handler is typically not a position
to handle them in a meaningfull way.
So disable them during suspend and enable them during resume.
Also make sure they are always disabled on hot-unplugged CPUs.
This new code assumes that suspend always hotunplugs all
non BP CPUs.
v2: Remove the WARN_ONs Thomas objected to.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Bugfix
The ifdef for the apic clear on shutdown for the 64bit intel thermal
vector was incorrect and never triggered. Fix that.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: bug fix (with tolerant == 3)
do_exit cannot be called directly from the exception handler because
it can sleep and the exception handler runs on the exception stack.
Use force_sig() instead.
Based on a earlier patch by Ying Huang who debugged the problem.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: Bug fix
This fixes a long standing bug in the machine check code. On resume the
boot CPU wouldn't get its vendor specific state like thermal handling
reinitialized. This means the boot cpu wouldn't ever get any thermal
events reported again.
Call the respective initialization functions on resume
v2: Remove ancient init because they don't have a resume device anyways.
Pointed out by Thomas Gleixner.
v3: Now fix the Subject too to reflect v2 change
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, vm86: fix preemption bug
x86, olpc: fix model detection without OFW
x86, hpet: fix for LS21 + HPET = boot hang
x86: CPA avoid repeated lazy mmu flush
x86: warn if arch_flush_lazy_mmu_cpu is called in preemptible context
x86/paravirt: make arch_flush_lazy_mmu/cpu disable preemption
x86, pat: fix warn_on_once() while mapping 0-1MB range with /dev/mem
x86/cpa: make sure cpa is safe to call in lazy mmu mode
x86, ptrace, mm: fix double-free on race
Impact: build fix, cleanup
A couple of arch setup callbacks were mistakenly in apic_32.c, breaking
the build.
Also simplify the code a bit.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Move the 32-bit extended-arch APIC drivers to arch/x86/kernel/apic/
too, and rename apic_64.c to probe_64.c.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.
Move them to arch/x86/kernel/apic/*, and also remove
the 'gen' prefix from those which had it.
Also move APIC related functionality: the IO-APIC driver,
the NMI and the IPI code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Now that all APIC code is consolidated there's nothing 'gen' about
apics anymore - so rename 'struct genapic' to 'struct apic'.
This shortens the code and is nicer to read as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
- misc other cleanups that change the md5 signature
- consolidate global variables
- remove unnecessary __numaq_mps_oem_check() wrapper
- make numaq_mps_oem_check static
- update copyrights
- misc other cleanups pointed out by checkpatch
Signed-off-by: Ingo Molnar <mingo@elte.hu>
These are cleanups that change the md5 signature:
- asm/ => linux/ include conversion
- simplify the code flow of find_unisys_acpi_oem_table()
- move ACPI methods into one #ifdef block
- remove 0/NULL initialization of statics
- simplify/standardize printouts
- update copyrights
- more cleanups, pointed out by checkpatch
arch/x86/kernel/es7000_32.o:
text data bss dec hex filename
2693 192 44 2929 b71 es7000_32.o.before
2688 192 44 2924 b6c es7000_32.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
- a number of structure definitions were stale
- remove needless wrappers around apic definitions
- fix details noticed by checkpatch
No code changed:
md5:
029d8fde0aaf6e934ea63bd8b36430fd es7000_32.o.before.asm
029d8fde0aaf6e934ea63bd8b36430fd es7000_32.o.after.asm
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
In the subarch times there were a number of externs between
various bits of the ES7000 code. Now that there's a single
es7000-platform support file, the externs can be removed and
the functions can be changed the statics.
Beyond the cleanup factor, this also shrinks the size of the
kernel image a bit:
arch/x86/kernel/es7000_32.o:
text data bss dec hex filename
2813 192 44 3049 be9 es7000_32.o.before
2693 192 44 2929 b71 es7000_32.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There were multiple definitions of apicid_cluster() scattered around
in APIC drivers - but the definitions are equivalent to the already
existing generic APIC_CLUSTER() method.
So remove apicid_cluster() and change all users to APIC_CLUSTER().
No code changed:
md5:
1b8244ba8d3d6a454593ce10f09dfa58 summit_32.o.before.asm
1b8244ba8d3d6a454593ce10f09dfa58 summit_32.o.after.asm
md5:
a593d98a882bf534622c70d9568497ac es7000_32.o.before.asm
a593d98a882bf534622c70d9568497ac es7000_32.o.after.asm
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
- remove unnecessary indirections that were artifacts of the subarch code
- clean up include file section
- clean up various small details
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
APIC_DEFINITION was a hack from the x86 subarch times, it has no
meaning anymore - remove it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
- make oprofile build
- select X86_X2APIC from X86_UV - it relies on it
- export genapic for oprofile modular build
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
make it simpler, don't need have one extra struct.
v2: fix the sgi_uv build
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
1. move localise_nmi_watchdog() later
2. change setup_boot_APIC_clock() to setup_boot_clock() for 64-bit
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
set default value early - this allows the removal of a number
of dynamic initialization codepaths, and an #ifdef.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix powernow-k8 when acpi=off (or other error).
There was a spurious change introduced into powernow-k8 in this patch:
so that we try to "restore" the cpus_allowed we never saved. We revert
that file.
See lkml "[PATCH] x86/powernow: fix cpus_allowed brokage when
acpi=off" from Yinghai for the bug report.
Cc: Mike Travis <travis@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Commit 3d2a71a596 ("x86, traps: converge
do_debug handlers") changed the preemption disable logic of do_debug()
so vm86_handle_trap() is called with preemption disabled resulting in:
BUG: sleeping function called from invalid context at include/linux/kernel.h:155
in_atomic(): 1, irqs_disabled(): 0, pid: 3005, name: dosemu.bin
Pid: 3005, comm: dosemu.bin Tainted: G W 2.6.29-rc1 #51
Call Trace:
[<c050d669>] copy_to_user+0x33/0x108
[<c04181f4>] save_v86_state+0x65/0x149
[<c0418531>] handle_vm86_trap+0x20/0x8f
[<c064e345>] do_debug+0x15b/0x1a4
[<c064df1f>] debug_stack_correct+0x27/0x2c
[<c040365b>] sysenter_do_call+0x12/0x2f
BUG: scheduling while atomic: dosemu.bin/3005/0x10000001
Restore the original calling convention and reenable preemption before
calling handle_vm86_trap().
Reported-by: Michal Suchanek <hramrach@centrum.cz>
Cc: stable@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix wrong disabling of cpu features
an amd system got this strange output:
CPU: CPU feature monitor disabled due to lack of CPUID level 0x5
but in /proc/cpuinfo I have:
cpuid level : 5
on intel system:
CPU: CPU feature monitor disabled due to lack of CPUID level 0x5
CPU: CPU feature dca disabled due to lack of CPUID level 0x9
but in /proc/cpuinfo i have:
cpuid level : 11
Tt turns out there is a typo, and we should use level member in df.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix "garbled display, laptop is unusable" bug
Commit e51a1ac2df ("x86, olpc: fix endian
bug in openfirmware workaround") breaks model comparison on OLPC; the value
0xc2 needs to be scaled up by olpc_board().
The pre-patch version was wrong, but accidentally worked anyway
(big-endian 0xc2 is big enough to satisfy all other board revisions,
but little endian 0xc2 is not).
Signed-off-by: Chris Ball <cjb@laptop.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Andres Salomon <dilinger@queued.net>
Cc: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In general, the only definitions that assembly files can use
are in _types.S headers (where available), so convert them.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
The uv_hub_send_ipi() function needs to set the full apicid in the
UVH_IPI_INT mmr.
Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Convert the c/p state "power" tracer to use tracepoints. Avoids a
function call when the tracer is disabled.
Signed-off-by: Jason Baron <jbaron@redhat.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
