On 07/23/2015 07:13 PM, Vince Weaver wrote: > > This manpage patch relates to the addition of the AUX sample flag > AUX_FLAG_OVERWRITE as added in the following commit: Thanks, Vince. Applied. Cheers, Michael > commit 2023a0d2829e521fe6ad6b9907f3f90bfbf57142 > Author: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> > > perf: Support overwrite mode for the AUX area > > Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > Cc: Borislav Petkov <bp@xxxxxxxxx> > Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> > Cc: H. Peter Anvin <hpa@xxxxxxxxx> > Cc: Kaixu Xia <kaixu.xia@xxxxxxxxxx> > Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > Cc: Mike Galbraith <efault@xxxxxx> > Cc: Paul Mackerras <paulus@xxxxxxxxx> > Cc: Robert Richter <rric@xxxxxxxxxx> > Cc: Stephane Eranian <eranian@xxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: acme@xxxxxxxxxxxxx > Cc: adrian.hunter@xxxxxxxxx > Cc: kan.liang@xxxxxxxxx > Cc: markus.t.metzger@xxxxxxxxx > Cc: mathieu.poirier@xxxxxxxxxx > Link: http://lkml.kernel.org/r/1421237903-181015-9-git-send-email-alexander.shishkin@xxxxxxxxxxxxxxx > Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> > > Signed-off-by: Vince Weaver <vincent.weaver@xxxxxxxxx> > > diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2 > index dfb0b64..238eb62 100644 > --- a/man2/perf_event_open.2 > +++ b/man2/perf_event_open.2 > @@ -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 > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
