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perf_event_open.2: 4.1 adds AUX_FLAG_OVERWRITE support 

This manpage patch relates to the addition of the AUX sample flag
AUX_FLAG_OVERWRITE as added in the following commit:

	commit 2023a0d2829e521fe6ad6b9907f3f90bfbf57142
	Author: Alexander Shishkin <alexander.shishkin@linux.intel.com>

	perf: Support overwrite mode for the AUX area

	Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
	Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
	Cc: Borislav Petkov <bp@alien8.de>
	Cc: Frederic Weisbecker <fweisbec@gmail.com>
	Cc: H. Peter Anvin <hpa@zytor.com>
	Cc: Kaixu Xia <kaixu.xia@linaro.org>
	Cc: Linus Torvalds <torvalds@linux-foundation.org>
	Cc: Mike Galbraith <efault@gmx.de>
	Cc: Paul Mackerras <paulus@samba.org>
	Cc: Robert Richter <rric@kernel.org>
	Cc: Stephane Eranian <eranian@google.com>
	Cc: Thomas Gleixner <tglx@linutronix.de>
	Cc: acme@infradead.org
	Cc: adrian.hunter@intel.com
	Cc: kan.liang@intel.com
	Cc: markus.t.metzger@intel.com
	Cc: mathieu.poirier@linaro.org
	Link: http://lkml.kernel.org/r/1421237903-181015-9-git-send-email-alexander.shishkin@linux.intel.com
	Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This commit is contained in:
Vince Weaver 2015-07-23 13:13:52 -04:00 committed by Michael Kerrisk
parent 1fda209c88
commit b1355f6a4b
1 changed files with 13 additions and 0 deletions
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13
man2/perf_event_open.2
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@ -1670,6 +1670,15 @@ rlimit as well as the
.I perf_event_mlock_kb
allowance.
By default the AUX buffer will be truncated if it will not fit
in the available space in the ring buffer.
If the AUX buffer is mapped as a read only buffer, then it will
operate in ring buffer mode where old data will be overwritten
by new.
In overwrite mode it might not be possible to infer where the
new data began, and it is the consumer's job to disable
measurement while reading to avoid possible data races.
The
.IR aux_head " and " aux_tail
ring buffer pointers have the same behavior and ordering
@ -2476,6 +2485,10 @@ describes the aux update.
.B PERF_AUX_FLAG_TRUNCATED
if set then the data returned was truncated to fit the available
buffer size.
.TP
.B PERF_AUX_FLAG_OVERWRITE
.\" commit 2023a0d2829e521fe6ad6b9907f3f90bfbf57142
if set then the data returned has overwritten previous data.
.RE
.RE
.RE