[tip:perf/core] tools lib traceevent: Man page for tep_parse_header_page()

tip-bot for Tzvetomir Stoyanov
2019-05-18T09:17:19Z

Commit-ID: 73b6b470f60641cf763eab60640b6dd9360297c7
Gitweb: https://git.kernel.org/tip/73b6b470f60641cf763eab60640b6dd9360297c7
Author: Tzvetomir Stoyanov <tstoyanov@vmware.com>
AuthorDate: Fri, 10 May 2019 15:56:31 -0400
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 15 May 2019 16:36:48 -0300

tools lib traceevent: Man page for tep_parse_header_page()

Create man page for tep_parse_header_page() libtraceevent API.

Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linux-trace-devel@vger.kernel.org
Link: http://lore.kernel.org/linux-trace-devel/20190503091119.23399-25-tstoyanov@vmware.com
Link: http://lkml.kernel.org/r/20190510200110.093108279@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
.../Documentation/libtraceevent-parse_head.txt | 82 ++++++++++++++++++++++
1 file changed, 82 insertions(+)

diff --git a/tools/lib/traceevent/Documentation/libtraceevent-parse_head.txt b/tools/lib/traceevent/Documentation/libtraceevent-parse_head.txt
new file mode 100644
index 000000000000..c90f16c7d8e6
--- /dev/null
+++ b/tools/lib/traceevent/Documentation/libtraceevent-parse_head.txt
@@ -0,0 +1,82 @@
+libtraceevent(3)
+================
+
+NAME
+----
+tep_parse_header_page - Parses the data stored in the header page.
+
+SYNOPSIS
+--------
+[verse]
+--
+*#include <event-parse.h>*
+
+int *tep_parse_header_page*(struct tep_handle pass:[*]_tep_, char pass:[*]_buf_, unsigned long _size_, int _long_size_);
+--
+
+DESCRIPTION
+-----------
+The _tep_parse_header_page()_ function parses the header page data from _buf_,
+and initializes the _tep_, trace event parser context, with it. The buffer
+_buf_ is with _size_, and is supposed to be copied from
+tracefs/events/header_page.
+
+Some old kernels do not have header page info, in this case the
+_tep_parse_header_page()_ function can be called with _size_ equal to 0. The
+_tep_ context is initialized with default values. The _long_size_ can be used in
+this use case, to set the size of a long integer to be used.
+
+RETURN VALUE
+------------
+The _tep_parse_header_page()_ function returns 0 in case of success, or -1
+in case of an error.
+
+EXAMPLE
+-------
+[source,c]
+--
+#include <event-parse.h>
+...
+struct tep_handle *tep = tep_alloc();
+...
+char *buf;
+int size;
+buf = read_file("/sys/kernel/tracing/events/header_page", &size);
+if (tep_parse_header_page(tep, buf, size, sizeof(unsigned long)) != 0) {
+ /* Failed to parse the header page */