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:
commit e8c6deac69629c0cb97c3d3272f8631ef17f8f0f
Author: Alexander Shishkin <[email protected]>
perf: Add data_{offset,size} to user_page
Signed-off-by: Alexander Shishkin <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Kaixu Xia <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Robert Richter <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/1421237903-181015-2-git-send-email-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Vince Weaver <[email protected]>
diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2
index 01ee579..8bd37da 100644
--- a/man2/perf_event_open.2
+++ b/man2/perf_event_open.2
@@ -1348,6 +1348,9 @@ 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
@@ -1564,6 +1567,16 @@ 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.