x86/tsc: Sync test only for the first cpu in a package
authorThomas Gleixner <tglx@linutronix.de>
Sat, 19 Nov 2016 13:47:39 +0000 (13:47 +0000)
committerThomas Gleixner <tglx@linutronix.de>
Tue, 29 Nov 2016 18:23:17 +0000 (19:23 +0100)
commita36f5136814b6a87601220927cb9ad9ecc731e92
tree8f216d647d363e058d3d419d9a95198ad8ded609
parent1d0095feea591bbd94f35d8a98aed746319783e1
x86/tsc: Sync test only for the first cpu in a package

If the TSC_ADJUST MSR is available all CPUs in a package are forced to the
same value. So TSCs cannot be out of sync when the first CPU in the package
was in sync.

That allows to skip the sync test for all CPUs except the first starting
CPU in a package.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20161119134017.809901363@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/include/asm/tsc.h
arch/x86/kernel/tsc_sync.c