diff options
author | Steven Rostedt (Red Hat) <rostedt@goodmis.org> | 2020-07-02 14:53:45 -0400 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-07-03 08:30:10 -0300 |
commit | 374855c5e4a76f7cc7f9aeb613c54929510eff18 (patch) | |
tree | 8cdcf0a22efc8a2b6f673e18fedf71d32e67d027 /tools/lib/traceevent/kbuffer-parse.c | |
parent | f18d5cf86cdb58eb50cafb5a5e20943ec7a61b1f (diff) |
tools lib traceevent: Add API to read time information from kbuffer
Add the functions kbuffer_subbuf_timestamp() and kbuffer_ptr_delta() to
get the timing data stored in the ring buffer that is used to produced
the time stamps of the records.
This is useful for tools like trace-cmd to be able to display the
content of the read data to understand why the records show the time
stamps that they do.
Link: http://lore.kernel.org/linux-trace-devel/20200625100516.365338-2-tz.stoyanov@gmail.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
[ Ported from trace-cmd.git ]
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/lkml/20200702185703.619656282@goodmis.org
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib/traceevent/kbuffer-parse.c')
-rw-r--r-- | tools/lib/traceevent/kbuffer-parse.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/tools/lib/traceevent/kbuffer-parse.c b/tools/lib/traceevent/kbuffer-parse.c index 27f3b07fdae8..583db99aee94 100644 --- a/tools/lib/traceevent/kbuffer-parse.c +++ b/tools/lib/traceevent/kbuffer-parse.c @@ -547,6 +547,34 @@ int kbuffer_load_subbuffer(struct kbuffer *kbuf, void *subbuffer) } /** + * kbuffer_subbuf_timestamp - read the timestamp from a sub buffer + * @kbuf: The kbuffer to load + * @subbuf: The subbuffer to read from. + * + * Return the timestamp from a subbuffer. + */ +unsigned long long kbuffer_subbuf_timestamp(struct kbuffer *kbuf, void *subbuf) +{ + return kbuf->read_8(subbuf); +} + +/** + * kbuffer_ptr_delta - read the delta field from a record + * @kbuf: The kbuffer to load + * @ptr: The record in the buffe. + * + * Return the timestamp delta from a record + */ +unsigned int kbuffer_ptr_delta(struct kbuffer *kbuf, void *ptr) +{ + unsigned int type_len_ts; + + type_len_ts = read_4(kbuf, ptr); + return ts4host(kbuf, type_len_ts); +} + + +/** * kbuffer_read_event - read the next event in the kbuffer subbuffer * @kbuf: The kbuffer to read from * @ts: The address to store the timestamp of the event (may be NULL to ignore) |