Messages in this thread | | | Subject | Re: [patch] perf_event_open.2: PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT | From | "Michael Kerrisk (man-pages)" <> | Date | Tue, 18 Oct 2016 08:14:56 +0200 |
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Hi Vince,
On 10/17/2016 04:50 PM, Vince Weaver wrote: > > Linux 4.2 reserved a new bit from the misc field in the perf_event_open > mmap sample buffer: > PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT > > Despite being reserved in the public include/uapi/linux/perf_event.h > header file, this bit is never set by the kernel, rather it is used > internally by the userspace "perf" utility to indicate that when > attempting to parse all of the /proc/xxx/maps files for the sample > it ended up taking too long so the scan was aborted. > > Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Thanks. Applied!
Cheers,
Michael
> diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2 > index fa8b1bd..59ad289 100644 > --- a/man2/perf_event_open.2 > +++ b/man2/perf_event_open.2 > @@ -1822,6 +1822,14 @@ See also > .BR PERF_RECORD_MISC_EXT_RESERVED " (since Linux 2.6.35)" > .\" commit 1676b8a077c352085d52578fb4f29350b58b6e74 > This indicates there is extended data available (currently not used). > +.TP > +.B PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT > +.\" commit 930e6fcd2bcce9bcd9d4aa7e755678d33f3fe6f4 > +This bit is not set by the kernel. > +It is reserved for the userspace perf utility to indicate that > +.I /proc/xxx/maps > +parsing was taking too long and stopped and thus the mmap > +records may be truncated. > .RE > .TP > .I type >
-- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/
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