drm/i915/psr: Fix race in intel_psr_work()

Browse source

Commit 5422b37c90 ("drm/i915/psr: Kill delays when activating psr
back.") switched from delayed work to the plain variant and while doing so
removed the check for work_busy() before scheduling a PSR activation.
This appears to cause consecutive executions of psr_activate() in this
scenario - after a worker picks up the PSR work item for execution and
before the work function can acquire the PSR mutex, a psr_flush() can
get hold of the mutex and schedule another PSR work. Without a psr_exit()
between the two psr_activate() calls, warning messages get printed.
Further, since we drop the mutex in the midst of psr_work() to wait for
PSR to idle, another work item can also get scheduled. Fix this by
returning if PSR was already active.

Fixes: 5422b37c90 ("drm/i915/psr: Kill delays when activating psr back.")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106948
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180625054741.3919-1-dhinakaran.pandiyan@intel.com

...

This commit is contained in:

Dhinakaran Pandiyan 2018-06-24 22:47:40 -07:00

parent cf5d862db2

commit c12e0643a0

1 changed files with 1 additions and 1 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

drivers/gpu/drm/i915/intel_psr.c

View file