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Update to upstream HEAD (v3.1-rc10-42-g2efd7c0).

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Chuck Ebbert 2011-10-21 20:01:25 -04:00
parent 62a1a480d4
commit 65b0d9b17d
3 changed files with 4 additions and 81 deletions
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73
cputimer-cure-lock-inversion.patch
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@ -1,73 +0,0 @@
Subject: cputimer: Cure lock inversion
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Mon Oct 17 11:50:30 CEST 2011
There's a lock inversion between the cputimer->lock and rq->lock; notably
the two callchains involved are:
update_rlimit_cpu()
sighand->siglock
set_process_cpu_timer()
cpu_timer_sample_group()
thread_group_cputimer()
cputimer->lock
thread_group_cputime()
task_sched_runtime()
->pi_lock
rq->lock
scheduler_tick()
rq->lock
task_tick_fair()
update_curr()
account_group_exec()
cputimer->lock
Where the first one is enabling a CLOCK_PROCESS_CPUTIME_ID timer, and
the second one is keeping up-to-date.
This problem was introduced by e8abccb7193 ("posix-cpu-timers: Cure
SMP accounting oddities").
Cure the problem by removing the cputimer->lock and rq->lock nesting,
this leaves concurrent enablers doing duplicate work, but the time
wasted should be on the same order otherwise wasted spinning on the
lock and the greater-than assignment filter should ensure we preserve
monotonicity.
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Simon Kirby <sim@hostway.ca>
Cc: stable@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
kernel/posix-cpu-timers.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
Index: linux-2.6/kernel/posix-cpu-timers.c
===================================================================
--- linux-2.6.orig/kernel/posix-cpu-timers.c
+++ linux-2.6/kernel/posix-cpu-timers.c
@@ -274,9 +274,7 @@ void thread_group_cputimer(struct task_s
struct task_cputime sum;
unsigned long flags;
- spin_lock_irqsave(&cputimer->lock, flags);
if (!cputimer->running) {
- cputimer->running = 1;
/*
* The POSIX timer interface allows for absolute time expiry
* values through the TIMER_ABSTIME flag, therefore we have
@@ -284,8 +282,11 @@ void thread_group_cputimer(struct task_s
* it.
*/
thread_group_cputime(tsk, &sum);
+ spin_lock_irqsave(&cputimer->lock, flags);
+ cputimer->running = 1;
update_gt_cputime(&cputimer->cputime, &sum);
- }
+ } else
+ spin_lock_irqsave(&cputimer->lock, flags);
*times = cputimer->cputime;
spin_unlock_irqrestore(&cputimer->lock, flags);
}

11
kernel.spec
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@ -84,7 +84,7 @@ Summary: The Linux kernel
# The rc snapshot level
%define rcrev 10
# The git snapshot level
%define gitrev 0
%define gitrev 1
# Set rpm version accordingly
%define rpmversion 3.%{upstream_sublevel}.0
%endif
@ -749,9 +749,6 @@ Patch21002: mmc-Always-check-for-lower-base-frequency-quirk-for-.patch
Patch21020: 0001-mm-vmscan-Limit-direct-reclaim-for-higher-order-allo.patch
Patch21021: 0002-mm-Abort-reclaim-compaction-if-compaction-can-procee.patch
# rhbz #746485
Patch21030: cputimer-cure-lock-inversion.patch
%endif
BuildRoot: %{_tmppath}/kernel-%{KVERREL}-root
@ -1379,9 +1376,6 @@ ApplyPatch utrace.patch
ApplyPatch 0001-mm-vmscan-Limit-direct-reclaim-for-higher-order-allo.patch
ApplyPatch 0002-mm-Abort-reclaim-compaction-if-compaction-can-procee.patch
# rhbz #746485
ApplyPatch cputimer-cure-lock-inversion.patch
# END OF PATCH APPLICATIONS
%endif
@ -2090,8 +2084,9 @@ fi
# ||----w |
# || ||
%changelog
* Fri Oct 21 2011 Chuck Ebbert <cebbert@redhat.com>
* Fri Oct 21 2011 Chuck Ebbert <cebbert@redhat.com> 3.1.0-0.rc10.git1.1
- Require grubby >= 8.3-1 like F16 does.
- Update to upstream HEAD (v3.1-rc10-42-g2efd7c0).
* Fri Oct 21 2011 Dave Jones <davej@redhat.com>
- Lower severity of Radeon lockup messages.

1
sources
View File

@ -1,2 +1,3 @@
398e95866794def22b12dfbc15ce89c0 linux-3.0.tar.bz2
6a91efe6505579a181c5f5e1a68f6c3a patch-3.1-rc10.bz2
aaf9baa66a0fde2b3824ab618ac1be6c patch-3.1-rc10-git1.bz2