Re: [patch 04/11] perf_event_open.2: 4.1 data_offset and data_size fields

["Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>]

On 07/23/2015 07:11 PM, Vince Weaver wrote:
> 
> This manpage patch relates to the addition of the data_offset
> and data_size fields to the perf_event mmap buffer, as added
> in the following commit:

Thanks, Vince. Applied.

Cheers,

Michael



> 	commit e8c6deac69629c0cb97c3d3272f8631ef17f8f0f
> 	Author: Alexander Shishkin <alexander.shishkin@linux.intel.com>
> 
> 	perf: Add data_{offset,size} to user_page
> 
> 	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/1421237903-181015-2-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>
> 
> diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2
> index 09eda9a..a3bebaa 100644
> --- a/man2/perf_event_open.2
> +++ b/man2/perf_event_open.2
> @@ -1414,6 +1414,9 @@ struct perf_event_mmap_page {
>      __u64 __reserved[120];   /* Pad to 1k */
>      __u64 data_head;         /* head in the data section */
>      __u64 data_tail;         /* user-space written tail */
> +    __u64 data_offset;       /* where the buffer starts */
> +    __u64 data_size;         /* data buffer size */
> +
>  }
>  .fi
>  .in
> @@ -1630,6 +1633,16 @@ the
>  .I data_tail
>  value should be written by user space to reflect the last read data.
>  In this case, the kernel will not overwrite unread data.
> +.TP
> +.IR data_offset " (since Linux 4.1)"
> +.\" commit e8c6deac69629c0cb97c3d3272f8631ef17f8f0f
> +Contains the offset of the location in the mmap buffer
> +where perf sample data begins.
> +.TP
> +.IR data_size " (since Linux 4.1)"
> +.\" commit e8c6deac69629c0cb97c3d3272f8631ef17f8f0f
> +Contains the size of the perf sample region within
> +the mmap buffer.
>  .PP
>  The following 2^n ring-buffer pages have the layout described below.
>  
> 


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/