Commit Graph

11 Commits

Author SHA1 Message Date
Haixia Shi
179bd77ab6 SF: more DispSync improvements.
Pass the reference time to DispSyncThread. Since the phase offset is calculated
using timestamps relative to the reference time, we must also adjust the phase
offset by the same reference time when computing the next refresh time.

Always reset phase offset to zero when updating the reference time because the
reference time equals the first timestamp.

After beginResync() we need to keep HW vsync enabled until the model is updated.

Bug: 25113115
Change-Id: I8eae227bee91c24a99bf8e57fbebceb98d29c77d
Test: check in systrace that app/sf vsync events have correct phase
2016-07-20 04:16:16 -07:00
Haixia Shi
95cda3b92f SF: use first sample timestamp as reference.
Do not use the absolute 64-bit nsecs_t timestamp directly in phase
and error calculations. Compared to the estimated vsync period, the
timestamp tend to many orders of magnitudes larger, and consequently
the integer modulo operation used to calculate phase and error can
be very sensitive to tiny fluctuation in vsync period.

Bug: 25113115
Test: set kTraceDetailedInfo=true; see Phase and Error are stable in systrace

Change-Id: I687703eec31b1072c606898c0424a96c0a8ca033
2016-07-20 04:16:16 -07:00
Raj Kamal
67ec1ad104 sf: Avoid disabling DispSync resync
Avoid disabling DispSync resync if app and SF events aren't
using phase offsets. This prevents hardware VSYNC from turning
on always whenever something needs to be drawn, thereby
bringing down the power numbers.

Change-Id: I83c8f79eb46b9fdaa730ec32767ebed3286347b8
2015-10-06 03:22:28 -06:00
Dan Stoza
9c64757f65 SF: Reduce resync samples without present
Reduces the number of resync samples that DispSync will attempt to
collect without an intervening present from 12 to 4. The former value
was causing excessive power draw for some vendors' implementations, and
reducing it doesn't seem to harm anything.

Bug: 20724456
Change-Id: Ifd6e0490be67756ed001d509a38e8a36953b4618
2015-05-29 13:00:23 -07:00
Lajos Molnar
67d8bd66aa surfaceflinger: add getDisplayStats() method
This is used by media service to schedule video frames at the
proper time, based on precise vsync timings.

Bug: 14659809
Change-Id: I1a90603f3dc09dca9aa4f90a3aa845fab56e0a5e
2014-09-18 17:03:20 -07:00
Andy McFadden
645b1f7ffb Replace "lower power mode" experiment
This replaces the previous low-power mode experiment, which
discarded refresh events, with a new experiment that alters
the refresh period.

(see also I2849e5ea335c0d2509fea1c315392bce7f20451d )

The feature is enabled by specifying a nonzero value for the
"refresh skip count", which indicates the number of periods
to skip.  For example, the command:

  adb shell service call SurfaceFlinger 1016 i32 1

sets a skip count of '1', yielding a 30Hz refresh rate on a device
with a 60Hz display.  Changing the last value to '2' would set the
refresh to 20Hz.  '0' returns to the default behavior.

Bug 15523257

Change-Id: I00039c22a55750e74035644c63800e4bee1c774a
2014-06-11 10:19:08 -07:00
Andy McFadden
5167ec68fe Disable DispSync resync when not needed
If app and SF events aren't using phase offsets, we don't need
to maintain the DispSync model.  We just turn hardware VSYNC on
whenever something wants to draw.  This avoids some edge cases
where we were doing too much resync work.

Also, updated the systrace output.  The "VsyncOn" line was a
combination of SF and app event threads, and would occasionally
be very weird.  Removed VsyncOn, renamed VSYNC to VSYNC-app,
and added VSYNC-sf.

Also, added more details to the --dispsync dumpsys output.

Also, renamed global constants to not look like local variables.

Bug 15516453

Change-Id: I0da10b72f0d9a7b7eb5202d87cc18967f698adbd
2014-06-10 13:12:19 -07:00
Andy McFadden
c751e92c56 Add "dumpsys SurfaceFlinger --dispsync"
Dumps the current DispSync state.

Bug 14651879

Change-Id: Ide4e6dbd58b117bc1a6b97b57d10cd92ec86dc84
2014-05-08 16:14:41 -07:00
Andy McFadden
41d67d7ab4 Improve SurfaceFlinger PTS estimation
Get the next refresh time from DispSync instead of guessing based
on the current time.

Change-Id: I8dc72a3217bfd4e9b4c905034194d1a298cad69a
2014-05-02 10:56:54 -07:00
Ruchi Kandoi
f52b3c88f1 SurfaceFlinger: Adds the functionality to reduce refresh rate to half of
the default.

Feature added for the low power mode.

Change-Id: I2849e5ea335c0d2509fea1c315392bce7f20451d
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
2014-05-01 18:29:33 +00:00
Jamie Gennis
faf77cce9d SurfaceFlinger: SW-based vsync events
This change adds the DispSync class, which models the hardware vsync event
times to allow vsync event callbacks to be done at an arbitrary phase offset
from the hardware vsync.  This can be used to reduce the minimum latency from
Choreographer wake-up to on-screen image presentation.

Bug: 10624956
Change-Id: I8c7a54ceacaa4d709726ed97b0dcae4093a7bdcf
2013-10-07 17:59:53 -07:00