perf: Extend the mmap control page with time (TSC) fields
Extend the mmap control page with fields so that userspace can compute
time deltas relative to the provided time fields.
Currently only implemented for x86 with constant and nonstop TSC.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Arun Sharma <asharma@fb.com>
Link: http://lkml.kernel.org/n/tip-3u1jucza77j3wuvs0x2bic0f@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 5311b79..0b91db2 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -291,12 +291,14 @@
__s64 offset; /* add to hardware event value */
__u64 time_enabled; /* time event active */
__u64 time_running; /* time event on cpu */
+ __u32 time_mult, time_shift;
+ __u64 time_offset;
/*
* Hole for extension of the self monitor capabilities
*/
- __u64 __reserved[123]; /* align to 1k */
+ __u64 __reserved[121]; /* align to 1k */
/*
* Control data for the mmap() data buffer.