Messages in this thread Patch in this message | | | From | Wang Nan <> | Subject | [PATCH 1/2] perf_event_open.2: Document PERF_EVENT_IOC_PAUSE_OUTPUT | Date | Fri, 21 Oct 2016 11:38:12 +0000 |
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Linux 4.7 (86e7972f690c1017fd086cdfe53d8524e68c661c) introduces PERF_EVENT_IOC_PAUSE_OUTPUT feature. Document it.
Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> --- man2/perf_event_open.2 | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2 index fade28c..2d3acad 100644 --- a/man2/perf_event_open.2 +++ b/man2/perf_event_open.2 @@ -2865,7 +2865,18 @@ The argument is a BPF program file descriptor that was created by a previous .BR bpf (2) system call. -.SS Using prctl(2) +.TP +.BR PERF_EVENT_IOC_PAUSE_OUTPUT " (since Linux 4.7)" +.\" commit 86e7972f690c1017fd086cdfe53d8524e68c661c +This allows pausing and resuming the event's ring-buffer. A +paused ring-buffer does not prevent samples generation, but simply +discards them. The discarded samples are considered lost, causes +.BR PERF_RECORD_LOST +to be generated when possible. + +The argument is an integer. Nonzero value pauses the ring-buffer, +zero value resumes the ring-buffer. +.SS Using prctl A process can enable or disable all the event groups that are attached to it using the .BR prctl (2) -- 2.10.1
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