diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_gt_requests.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_gt_requests.c | 83 |
1 files changed, 79 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c index 353809ac2754..3dc13ecf41bf 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c @@ -4,6 +4,8 @@ * Copyright © 2019 Intel Corporation */ +#include <linux/workqueue.h> + #include "i915_drv.h" /* for_each_engine() */ #include "i915_request.h" #include "intel_gt.h" @@ -29,6 +31,79 @@ static void flush_submission(struct intel_gt *gt) intel_engine_flush_submission(engine); } +static void engine_retire(struct work_struct *work) +{ + struct intel_engine_cs *engine = + container_of(work, typeof(*engine), retire_work); + struct intel_timeline *tl = xchg(&engine->retire, NULL); + + do { + struct intel_timeline *next = xchg(&tl->retire, NULL); + + /* + * Our goal here is to retire _idle_ timelines as soon as + * possible (as they are idle, we do not expect userspace + * to be cleaning up anytime soon). + * + * If the timeline is currently locked, either it is being + * retired elsewhere or about to be! + */ + if (mutex_trylock(&tl->mutex)) { + retire_requests(tl); + mutex_unlock(&tl->mutex); + } + intel_timeline_put(tl); + + GEM_BUG_ON(!next); + tl = ptr_mask_bits(next, 1); + } while (tl); +} + +static bool add_retire(struct intel_engine_cs *engine, + struct intel_timeline *tl) +{ + struct intel_timeline *first; + + /* + * We open-code a llist here to include the additional tag [BIT(0)] + * so that we know when the timeline is already on a + * retirement queue: either this engine or another. + * + * However, we rely on that a timeline can only be active on a single + * engine at any one time and that add_retire() is called before the + * engine releases the timeline and transferred to another to retire. + */ + + if (READ_ONCE(tl->retire)) /* already queued */ + return false; + + intel_timeline_get(tl); + first = READ_ONCE(engine->retire); + do + tl->retire = ptr_pack_bits(first, 1, 1); + while (!try_cmpxchg(&engine->retire, &first, tl)); + + return !first; +} + +void intel_engine_add_retire(struct intel_engine_cs *engine, + struct intel_timeline *tl) +{ + if (add_retire(engine, tl)) + schedule_work(&engine->retire_work); +} + +void intel_engine_init_retire(struct intel_engine_cs *engine) +{ + INIT_WORK(&engine->retire_work, engine_retire); +} + +void intel_engine_fini_retire(struct intel_engine_cs *engine) +{ + flush_work(&engine->retire_work); + GEM_BUG_ON(engine->retire); +} + long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) { struct intel_gt_timelines *timelines = >->timelines; @@ -52,8 +127,8 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) } intel_timeline_get(tl); - GEM_BUG_ON(!tl->active_count); - tl->active_count++; /* pin the list element */ + GEM_BUG_ON(!atomic_read(&tl->active_count)); + atomic_inc(&tl->active_count); /* pin the list element */ spin_unlock_irqrestore(&timelines->lock, flags); if (timeout > 0) { @@ -74,7 +149,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) /* Resume iteration after dropping lock */ list_safe_reset_next(tl, tn, link); - if (!--tl->active_count) + if (atomic_dec_and_test(&tl->active_count)) list_del(&tl->link); else active_count += !!rcu_access_pointer(tl->last_request.fence); @@ -83,7 +158,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) /* Defer the final release to after the spinlock */ if (refcount_dec_and_test(&tl->kref.refcount)) { - GEM_BUG_ON(tl->active_count); + GEM_BUG_ON(atomic_read(&tl->active_count)); list_add(&tl->link, &free); } } |