From 2d4bd971f5baa51418625f379a69f5d58b5a0450 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 6 Mar 2020 15:46:47 +0000 Subject: [PATCH] drm/i915/gt: Close race between cacheline_retire and free If the cacheline may still be busy, atomically mark it for future release, and only if we can determine that it will never be used again, immediately free it. Closes: https://gitlab.freedesktop.org/drm/intel/issues/1392 Fixes: ebece7539242 ("drm/i915: Keep timeline HWSP allocated until idle across the system") Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: Mika Kuoppala Cc: Matthew Auld Reviewed-by: Mika Kuoppala Cc: # v5.2+ Link: https://patchwork.freedesktop.org/patch/msgid/20200306154647.3528345-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gt/intel_timeline.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c index 54e1e55f3c81..91debbc97c9a 100644 --- a/drivers/gpu/drm/i915/gt/intel_timeline.c +++ b/drivers/gpu/drm/i915/gt/intel_timeline.c @@ -192,11 +192,15 @@ static void cacheline_release(struct intel_timeline_cacheline *cl) static void cacheline_free(struct intel_timeline_cacheline *cl) { + if (!i915_active_acquire_if_busy(&cl->active)) { + __idle_cacheline_free(cl); + return; + } + GEM_BUG_ON(ptr_test_bit(cl->vaddr, CACHELINE_FREE)); cl->vaddr = ptr_set_bit(cl->vaddr, CACHELINE_FREE); - if (i915_active_is_idle(&cl->active)) - __idle_cacheline_free(cl); + i915_active_release(&cl->active); } int intel_timeline_init(struct intel_timeline *timeline,