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authorSuresh Siddha <suresh.b.siddha@intel.com>2011-11-04 23:42:17 +0100
committerIngo Molnar <mingo@elte.hu>2011-12-05 18:00:31 +0100
commit28a00184be261e3dc152ba0d664a067bbe235b6a (patch)
tree9c56ce8c758a244173c9b0016cac43f45609d4ed /arch/x86/include/asm/tsc.h
parentx86: Fix boot failures on older AMD CPU's (diff)
downloadlinux-28a00184be261e3dc152ba0d664a067bbe235b6a.tar.xz
linux-28a00184be261e3dc152ba0d664a067bbe235b6a.zip
x86, tsc: Skip TSC synchronization checks for tsc=reliable
tsc=reliable boot parameter is supposed to skip all the TSC stablility checks during boot time. On a 8-socket system where we want to run an experiment with the "tsc=reliable" boot option, TSC synchronization checks are not getting skipped and marking the TSC as not stable. Check for tsc_clocksource_reliable (which is set via tsc=reliable or for platforms supporting synthetic TSC_RELIABLE feature bit etc) and when set, skip the TSC synchronization tests during boot. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: John Stultz <johnstul@us.ibm.com> Tested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1320446537.15071.14.camel@sbsiddha-desk.sc.intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/include/asm/tsc.h')
-rw-r--r--arch/x86/include/asm/tsc.h2
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
index 83e2efd181e2..15d99153a96d 100644
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -51,6 +51,8 @@ extern int unsynchronized_tsc(void);
extern int check_tsc_unstable(void);
extern unsigned long native_calibrate_tsc(void);
+extern int tsc_clocksource_reliable;
+
/*
* Boot-time check whether the TSCs are synchronized across
* all CPUs/cores: