sync: allow async waits to be canceled

In order to allow drivers to cleanly handled teardown we need to allow them
to cancel pending async waits.  To do this cleanly, we move allocation of
sync_fence_waiter to the driver calling sync_async_wait().

Change-Id: Ifcd95648be6ec07026d67f810070a4310f099989
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit c80114fd8bfecfb60121d0a82c59610435604ce3)
sync: export sync API symbols

This is needed to allow modules to link against the sync subsystem

Change-Id: I15c1818de329f24e4113ef1d0923413b22fd0eff
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit 4fb837a718d33bbaba19c0ccfbb3e23fc92d8ad3)
sync: reorder sync_fence_release

Previously fence's pts were freed before the were the fence was removed from the
global fence list.  This led to a race with the debugfs support where it would
iterate over sync_pts that had been freed.

Change-Id: Ia3ddbf77de42ca593fc2dc353b5d04e42ddf3946
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit b9aad62eee535b743934e3be33a12359270975d3)
sync: optimize fence merges

If the two fences being merged contain sync_pts from the same timeline,
those two pts will be collapsed into a single pt representing the latter
of the two.

Change-Id: Iced7ebb7e5a17a0c8b1a2969ba3388a4edb9ecaf
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit 55e92560aea7277d61ed08e819b73ae29c039160)
sync: add internal refcounting to fences

If a fence is released while a timeline that one of it's pts is on is being
signaled, it is possible for that fence to be deleted before it is signaled.
This patch adds a refcount for internal references such as signaled pt
processing.

Change-Id: Ie8605e6fd2ac026c207220a03d84e1c1078ec719
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit 2d8498643c3a9c8776bfc954d974e709f165d976)
sync: add reference counting to timelines

If a timeline is destroyed while fences still hold pts on it, the reworked
fence release handler can cause the timeline to be freed before all it's points
are freed.

Change-Id: I1cd8ddb638eded7db9db446ff6b37f3dd165d6c4
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit 8b79db57632b7e9d45af8c0d4fda1db7f116b535)
sync: Fix error paths

Check the return value of get_unused_fd to make sure a valid
file descriptor is returned.

Make sure to call put_unused_fd even if an error occurs before
the fd can be used.

Change-Id: I0fe8f78d9e30ecfc4d271c5d875424543dae2d0f
Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
(cherry picked from commit 75574205e8c02e4bf561ae3a1d542befaeb8bcc4)
sync: change wait timeout to mirror poll semantics

Change-Id: Ib38e6d339d41885a33027752690d65a52b6897f6
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit 4bf8b3d9f736d614a7b2c18f54b9c4004f278ee3)
sync: fix erase-o in sync_fence_wait

Change-Id: I189707cf658a9f1f2943515c891b43961994e774
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit b033d86c307f1eb85d567f8cea51530230d2f169)
sync: clean up compiler warnings

Change-Id: I8a2ec5db652c61fd04571402067b37273b91e78f
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit f819bacd68cb99883563ed9d70944fa9b4b02505)
sync: dump sync state to console on timeout

Change-Id: I74bca6b4a2afa7ed5b1f5233c5165d2edddf269a
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit 344bd536923058faeccc8e6ad23c4a7c5f8ca0be)
sync: use correct signed type when handling SYNC_IOC_WAIT

Change-Id: Ic7d5adf9b145765e52b23186b8c3c793ccf29be7
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit fe7eb30dbc62d4e2f971c128e6c4cd0798055319)
sync: improve timeout dumps

Change-Id: I3b378d63c324c7b5862dd214f380b5e91131cc2a
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit 2c3e5cb08f29ba0e4b58c004d5f860db8e84fa8b)
sync: dump sync state of fence errors

Change-Id: I297a43aadf83504993040ea875c7f22d988628f1
Signed-off-by: Erik Gilling <konkers@android.com>
(cherry picked from commit e1f28cac507fc7c4fc7a7e03b6c8a356cf6688bc)