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| author | Andi Kleen <ak@linux.intel.com> | 2015-05-10 12:22:39 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-08-04 10:16:55 +0200 |
| commit | a94cab2376cb35f236be14e2833cef63a8762a31 (patch) | |
| tree | 666ded02a83b67d8772bc771d61dd6d1ae863f05 /arch/x86/kernel/tsc.c | |
| parent | b1bf72d6691cc33fc7763fc8ec77df42ca1a8702 (diff) | |
| download | linux-a94cab2376cb35f236be14e2833cef63a8762a31.tar.bz2 | |
perf/x86: Add a native_perf_sched_clock_from_tsc()
PEBSv3 has a raw TSC time stamp in its memory buffer that
later needs to to be converted to perf_clock.
Add a native_sched_clock_from_tsc() that works the same
as native_sched_clock(), but starts with an already given
TSC value.
Paravirt is ignored, it will just get the native clock.
But there isn't a para virtualized PEBS anyway.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1431285767-27027-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/tsc.c')
| -rw-r--r-- | arch/x86/kernel/tsc.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 7437b41f6a47..88e9a38c71a5 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -296,6 +296,14 @@ u64 native_sched_clock(void) return cycles_2_ns(tsc_now); } +/* + * Generate a sched_clock if you already have a TSC value. + */ +u64 native_sched_clock_from_tsc(u64 tsc) +{ + return cycles_2_ns(tsc); +} + /* We need to define a real function for sched_clock, to override the weak default version */ #ifdef CONFIG_PARAVIRT |