weston/src/timeline.h
Pekka Paalanen b502654b9f compositor: Implement JSON-timeline logging
Logging is activated and deactivated with the debug key binding 't'.
When activated, it creates a new log file, where it records the events.
The log file contains events and detailed object information entries in
JSON format, and is meant to be parsed in sequence from beginning to the
end.

The emitted events are mostly related to the output repaint cycle, like
when repaint begins, is submitted to GPU, and when it completes on a
vblank. This is recorded per-output. Also some per-surface events are
recorded, including when surface damage is flushed.

To reduce the log size, events refer to objects like outputs and
surfaces by id numbers. Detailed object information is emitted only as
needed: on the first object occurrence, and afterwards only if
weston_timeline_object::force_refresh asks for it.

The detailed information for surfaces includes the string returned by
weston_surface::get_label. Therefore it is important to set
weston_timeline_object::force_refresh = 1 whenever the string would
change, so that the new details get recorded.

A rudimentary parser and SVG generator can be found at:
https://github.com/ppaalanen/wesgr

The timeline logs can answer questions including:
- How does the compositor repaint cycle work timing-wise?
- When was the vblank deadline missed?
- What is the latency from surface commit to showing the new content on
  screen?
- How long does it take to process the scenegraph?

v2: weston_surface::get_description renamed to get_label.
v3: reafctor a bit into fprint_quoted_string().

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
2014-12-08 15:02:56 +02:00

63 lines
2.1 KiB
C

/*
* Copyright © 2014 Pekka Paalanen <pq@iki.fi>
* Copyright © 2014 Collabora, Ltd.
*
* Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name of the copyright holders not be used in
* advertising or publicity pertaining to distribution of the software
* without specific, written prior permission. The copyright holders make
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
* CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef WESTON_TIMELINE_H
#define WESTON_TIMELINE_H
extern int weston_timeline_enabled_;
struct weston_compositor;
void
weston_timeline_open(struct weston_compositor *compositor);
void
weston_timeline_close(void);
enum timeline_type {
TLT_END = 0,
TLT_OUTPUT,
TLT_SURFACE,
TLT_VBLANK,
};
#define TYPEVERIFY(type, arg) ({ \
typeof(arg) tmp___ = (arg); \
(void)((type)0 == tmp___); \
tmp___; })
#define TLP_END TLT_END, NULL
#define TLP_OUTPUT(o) TLT_OUTPUT, TYPEVERIFY(struct weston_output *, (o))
#define TLP_SURFACE(s) TLT_SURFACE, TYPEVERIFY(struct weston_surface *, (s))
#define TLP_VBLANK(t) TLT_VBLANK, TYPEVERIFY(const struct timespec *, (t))
#define TL_POINT(...) do { \
if (weston_timeline_enabled_) \
weston_timeline_point(__VA_ARGS__); \
} while (0)
void
weston_timeline_point(const char *name, ...);
#endif /* WESTON_TIMELINE_H */