]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
x86: ignore the sys_getcpu() tcache parameter
authorIngo Molnar <mingo@elte.hu>
Wed, 7 Nov 2007 17:37:48 +0000 (18:37 +0100)
committerThomas Gleixner <tglx@apollo.(none)>
Sat, 17 Nov 2007 15:27:00 +0000 (16:27 +0100)
commit4307d1e5ada595c87f9a4d16db16ba5edb70dcb1
treebae1a90cc162a0d5bd1a78290ffb1f445fc07d80
parent434b3d3209a8d8dcda63c3b14815659f4671b0a8
x86: ignore the sys_getcpu() tcache parameter

dont use the vgetcpu tcache - it's causing problems with tasks
migrating, they'll see the old cache up to a jiffy after the
migration, further increasing the costs of the migration.

In the worst case they see a complete bogus information from
the tcache, when a sys_getcpu() call "invalidated" the cache
info by incrementing the jiffies _and_ the cpuid info in the
cache and the following vdso_getcpu() call happens after
vdso_jiffies have been incremented.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/vdso/vgetcpu.c
kernel/sys.c