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 | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c new file mode 100644 index 000000000000..3dc13ecf41bf --- /dev/null +++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c @@ -0,0 +1,212 @@ +/* + * SPDX-License-Identifier: MIT + * + * Copyright © 2019 Intel Corporation + */ + +#include <linux/workqueue.h> + +#include "i915_drv.h" /* for_each_engine() */ +#include "i915_request.h" +#include "intel_gt.h" +#include "intel_gt_pm.h" +#include "intel_gt_requests.h" +#include "intel_timeline.h" + +static void retire_requests(struct intel_timeline *tl) +{ + struct i915_request *rq, *rn; + + list_for_each_entry_safe(rq, rn, &tl->requests, link) + if (!i915_request_retire(rq)) + break; +} + +static void flush_submission(struct intel_gt *gt) +{ + struct intel_engine_cs *engine; + enum intel_engine_id id; + + for_each_engine(engine, gt, id) + 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; + struct intel_timeline *tl, *tn; + unsigned long active_count = 0; + unsigned long flags; + bool interruptible; + LIST_HEAD(free); + + interruptible = true; + if (unlikely(timeout < 0)) + timeout = -timeout, interruptible = false; + + flush_submission(gt); /* kick the ksoftirqd tasklets */ + + spin_lock_irqsave(&timelines->lock, flags); + list_for_each_entry_safe(tl, tn, &timelines->active_list, link) { + if (!mutex_trylock(&tl->mutex)) { + active_count++; /* report busy to caller, try again? */ + continue; + } + + intel_timeline_get(tl); + 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) { + struct dma_fence *fence; + + fence = i915_active_fence_get(&tl->last_request); + if (fence) { + timeout = dma_fence_wait_timeout(fence, + interruptible, + timeout); + dma_fence_put(fence); + } + } + + retire_requests(tl); + + spin_lock_irqsave(&timelines->lock, flags); + + /* Resume iteration after dropping lock */ + list_safe_reset_next(tl, tn, link); + if (atomic_dec_and_test(&tl->active_count)) + list_del(&tl->link); + else + active_count += !!rcu_access_pointer(tl->last_request.fence); + + mutex_unlock(&tl->mutex); + + /* Defer the final release to after the spinlock */ + if (refcount_dec_and_test(&tl->kref.refcount)) { + GEM_BUG_ON(atomic_read(&tl->active_count)); + list_add(&tl->link, &free); + } + } + spin_unlock_irqrestore(&timelines->lock, flags); + + list_for_each_entry_safe(tl, tn, &free, link) + __intel_timeline_free(&tl->kref); + + return active_count ? timeout : 0; +} + +int intel_gt_wait_for_idle(struct intel_gt *gt, long timeout) +{ + /* If the device is asleep, we have no requests outstanding */ + if (!intel_gt_pm_is_awake(gt)) + return 0; + + while ((timeout = intel_gt_retire_requests_timeout(gt, timeout)) > 0) { + cond_resched(); + if (signal_pending(current)) + return -EINTR; + } + + return timeout; +} + +static void retire_work_handler(struct work_struct *work) +{ + struct intel_gt *gt = + container_of(work, typeof(*gt), requests.retire_work.work); + + intel_gt_retire_requests(gt); + schedule_delayed_work(>->requests.retire_work, + round_jiffies_up_relative(HZ)); +} + +void intel_gt_init_requests(struct intel_gt *gt) +{ + INIT_DELAYED_WORK(>->requests.retire_work, retire_work_handler); +} + +void intel_gt_park_requests(struct intel_gt *gt) +{ + cancel_delayed_work(>->requests.retire_work); +} + +void intel_gt_unpark_requests(struct intel_gt *gt) +{ + schedule_delayed_work(>->requests.retire_work, + round_jiffies_up_relative(HZ)); +} |