diff options
| author | Yong Zhang <yong.zhang0@gmail.com> | 2011-07-28 11:16:00 +0800 |
|---|---|---|
| committer | Daniel Wagner <wagi@monom.org> | 2018-07-26 06:43:31 +0200 |
| commit | 2c2ea558240cf3a94fe8ef80bb63a715bf81fb33 (patch) | |
| tree | a561eb180c5f6459c898dd5c2e694d4351f8e578 /kernel/cpu.c | |
| parent | 2ecbc4d7e92a3f69c714cdba89c2ddd4e1ac4fa2 (diff) | |
| download | linux-rt-2c2ea558240cf3a94fe8ef80bb63a715bf81fb33.tar.gz | |
hotplug: Reread hotplug_pcp on pin_current_cpu() retry
When retry happens, it's likely that the task has been migrated to
another cpu (except unplug failed), but it still derefernces the
original hotplug_pcp per cpu data.
Update the pointer to hotplug_pcp in the retry path, so it points to
the current cpu.
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110728031600.GA338@windriver.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/cpu.c')
| -rw-r--r-- | kernel/cpu.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 9897d70cb531..e343dbda85b6 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -107,9 +107,11 @@ static DEFINE_PER_CPU(struct hotplug_pcp, hotplug_pcp); */ void pin_current_cpu(void) { - struct hotplug_pcp *hp = this_cpu_ptr(&hotplug_pcp); + struct hotplug_pcp *hp; retry: + hp = this_cpu_ptr(&hotplug_pcp); + if (!hp->unplug || hp->refcount || preempt_count() > 1 || hp->unplug == current) { hp->refcount++; |