diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2020-12-17 09:15:24 +0000 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2020-12-17 19:56:17 +0000 |
| commit | e3ed90b8227eaf7d67ea0a2e81af9a09c71c8e8d (patch) | |
| tree | 7d8cebf69e0ad68a816a410e1a9ca786b2dc4f84 /drivers/gpu/drm/i915/gt/intel_breadcrumbs.h | |
| parent | 460d02ba50763e73da033448d0d57f0aea23d039 (diff) | |
drm/i915/gt: Drain the breadcrumbs just once
Matthew Brost pointed out that the while-loop on a shared breadcrumb was
inherently fraught with danger as it competed with the other users of
the breadcrumbs. However, in order to completely drain the re-arming irq
worker, the while-loop is a necessity, despite my optimism that we could
force cancellation with a couple of irq_work invocations.
Given that we can't merely drop the while-loop, use an activity counter on
the breadcrumbs to detect when we are parking the breadcrumbs for the
last time.
Based on a patch by Matthew Brost.
Reported-by: Matthew Brost <matthew.brost@intel.com>
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Fixes: 9d5612ca165a ("drm/i915/gt: Defer enabling the breadcrumb interrupt to after submission")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201217091524.10258-1-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_breadcrumbs.h')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_breadcrumbs.h | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h index ed3d1deabfbd..75cc9cff3ae3 100644 --- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h +++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.h @@ -19,7 +19,18 @@ intel_breadcrumbs_create(struct intel_engine_cs *irq_engine); void intel_breadcrumbs_free(struct intel_breadcrumbs *b); void intel_breadcrumbs_reset(struct intel_breadcrumbs *b); -void intel_breadcrumbs_park(struct intel_breadcrumbs *b); +void __intel_breadcrumbs_park(struct intel_breadcrumbs *b); + +static inline void intel_breadcrumbs_unpark(struct intel_breadcrumbs *b) +{ + atomic_inc(&b->active); +} + +static inline void intel_breadcrumbs_park(struct intel_breadcrumbs *b) +{ + if (atomic_dec_and_test(&b->active)) + __intel_breadcrumbs_park(b); +} static inline void intel_engine_signal_breadcrumbs(struct intel_engine_cs *engine) |