Our goal in wait_for_idle (intel_gt_retire_requests) is to the current workload *and* their idle barriers. This requires us to notice the late arrival of those, which is done by inspecting the list of active timelines. However, if a concurrent retirer is running that new timeline may not be added until after we drop the lock -- so flush concurrent retirers before we take the lock and inspect the list.
Closes: https://gitlab.freedesktop.org/drm/intel/issues/878 Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> --- drivers/gpu/drm/i915/gt/intel_gt_requests.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c index 9e75fa1b6bc1..fc691c130ba6 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c @@ -26,21 +26,18 @@ static bool retire_requests(struct intel_timeline *tl) return !i915_active_fence_isset(&tl->last_request); } -static bool flush_submission(struct intel_gt *gt) +static void flush_submission(struct intel_gt *gt) { struct intel_engine_cs *engine; enum intel_engine_id id; - bool active = false; if (!intel_gt_pm_is_awake(gt)) - return false; + return; for_each_engine(engine, gt, id) { - active |= intel_engine_flush_submission(engine); - active |= flush_work(&engine->retire_work); + intel_engine_flush_submission(engine); + flush_work(&engine->retire_work); } - - return active; } static void engine_retire(struct work_struct *work) @@ -126,7 +123,6 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) timeout = -timeout, interruptible = false; flush_submission(gt); /* kick the ksoftirqd tasklets */ - spin_lock(&timelines->lock); list_for_each_entry_safe(tl, tn, &timelines->active_list, link) { if (!mutex_trylock(&tl->mutex)) { @@ -153,6 +149,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) active_count += !retire_requests(tl); + flush_submission(gt); /* sync with concurrent retirees */ spin_lock(&timelines->lock); /* Resume iteration after dropping lock */ @@ -173,9 +170,6 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) list_for_each_entry_safe(tl, tn, &free, link) __intel_timeline_free(&tl->kref); - if (flush_submission(gt)) - active_count++; - return active_count ? timeout : 0; } -- 2.24.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
