From 7936a22dd4660d24b4ca0668c02b0372127cab44 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 14 Nov 2019 22:57:32 +0000 Subject: [PATCH] drm/i915/gt: Wait for new requests in intel_gt_retire_requests() Our callers fall into two categories, those passing timeout=0 who just want to flush request retirements and those passing a timeout that need to wait for submission completion (e.g. intel_gt_wait_for_idle()). Currently, we only wait for a snapshot of timelines at the start of the wait (but there was an expectation that new requests would cause timelines to appear at the end). However, our callers, such as intel_gt_wait_for_idle() before suspend, do require us to wait for the power management requests emitted by retirement as well. If we don't, then it takes an extra second or two for the background worker to flush the queue and mark the GT as idle. Fixes: 7e8057626640 ("drm/i915: Drop struct_mutex from around i915_retire_requests()") Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20191114225736.616885-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gt/intel_gt_requests.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c index b73229a84d85..ccbddddbbd52 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c @@ -33,7 +33,6 @@ 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); @@ -46,10 +45,8 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) 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? */ + if (!mutex_trylock(&tl->mutex)) continue; - } intel_timeline_get(tl); GEM_BUG_ON(!tl->active_count); @@ -74,9 +71,7 @@ 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) - active_count += !!rcu_access_pointer(tl->last_request.fence); - else + if (!--tl->active_count) list_del(&tl->link); mutex_unlock(&tl->mutex); @@ -92,7 +87,7 @@ 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); - return active_count ? timeout : 0; + return list_empty(&timelines->active_list) ? 0 : timeout; } int intel_gt_wait_for_idle(struct intel_gt *gt, long timeout) -- 2.30.2