From a1b58ee3cb34c433167b7b7d3465ab3ca0e3daf1 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Sun, 6 Oct 2019 17:49:54 +0100
Subject: drm/i915/gt: Treat a busy timeline as 'active' while waiting
Git-commit: a1b58ee3cb34c433167b7b7d3465ab3ca0e3daf1
Patch-mainline: v5.5-rc1
References: bsc#1152489
If we cannot claim the timeline->mutex while preparing for a wait on it,
we have to skip the timeline. In doing so, treat it as active so that
under a intel_gt_wait_for_idle() loop, we repeat the wait after
scheduling away.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191006165002.30312-4-chris@chris-wilson.co.uk
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
drivers/gpu/drm/i915/gt/intel_gt_requests.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index d69e78478eea..ca606b79fd5e 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -34,8 +34,10 @@ 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))
+ if (!mutex_trylock(&tl->mutex)) {
+ active_count++; /* report busy to caller, try again? */
continue;
+ }
intel_timeline_get(tl);
GEM_BUG_ON(!tl->active_count);
--
2.28.0