From 206c2f812fee530f7eda8ad0e97126aec3cd7c43 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 18 Mar 2019 21:23:46 +0000 Subject: [PATCH] drm/i915: Lock the gem_context->active_list while dropping the link On unpinning the intel_context, we remove it from the active list inside the GEM context. This list is supposed to be guarded by the GEM context mutex, so remember to take it! Fixes: 7e3d9a59410d ("drm/i915: Track active engines within a context") Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20190318212347.30146-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/intel_context.c | 15 +++++++++++---- drivers/gpu/drm/i915/intel_lrc.c | 3 --- drivers/gpu/drm/i915/intel_ringbuffer.c | 3 --- drivers/gpu/drm/i915/selftests/mock_engine.c | 2 -- 4 files changed, 11 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_context.c b/drivers/gpu/drm/i915/intel_context.c index 5a16c9bb2778..0ab894a058f6 100644 --- a/drivers/gpu/drm/i915/intel_context.c +++ b/drivers/gpu/drm/i915/intel_context.c @@ -165,13 +165,13 @@ intel_context_pin(struct i915_gem_context *ctx, if (err) goto err; + i915_gem_context_get(ctx); + GEM_BUG_ON(ce->gem_context != ctx); + mutex_lock(&ctx->mutex); list_add(&ce->active_link, &ctx->active_engines); mutex_unlock(&ctx->mutex); - i915_gem_context_get(ctx); - GEM_BUG_ON(ce->gem_context != ctx); - smp_mb__before_atomic(); /* flush pin before it is visible */ } @@ -194,9 +194,16 @@ void intel_context_unpin(struct intel_context *ce) /* We may be called from inside intel_context_pin() to evict another */ mutex_lock_nested(&ce->pin_mutex, SINGLE_DEPTH_NESTING); - if (likely(atomic_dec_and_test(&ce->pin_count))) + if (likely(atomic_dec_and_test(&ce->pin_count))) { ce->ops->unpin(ce); + mutex_lock(&ce->gem_context->mutex); + list_del(&ce->active_link); + mutex_unlock(&ce->gem_context->mutex); + + i915_gem_context_put(ce->gem_context); + } + mutex_unlock(&ce->pin_mutex); } diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 8d1cb81ba0f5..c949af7be8bd 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -1277,9 +1277,6 @@ static void execlists_context_unpin(struct intel_context *ce) ce->state->obj->pin_global--; i915_gem_object_unpin_map(ce->state->obj); i915_vma_unpin(ce->state); - - list_del(&ce->active_link); - i915_gem_context_put(ce->gem_context); } static int __context_pin(struct i915_vma *vma) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 5137f0140664..81b32bac2bcd 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -1430,9 +1430,6 @@ static void ring_context_unpin(struct intel_context *ce) { __context_unpin_ppgtt(ce->gem_context); __context_unpin(ce); - - list_del(&ce->active_link); - i915_gem_context_put(ce->gem_context); } static struct i915_vma * diff --git a/drivers/gpu/drm/i915/selftests/mock_engine.c b/drivers/gpu/drm/i915/selftests/mock_engine.c index 881450c694e9..7641b74ada98 100644 --- a/drivers/gpu/drm/i915/selftests/mock_engine.c +++ b/drivers/gpu/drm/i915/selftests/mock_engine.c @@ -126,8 +126,6 @@ static void hw_delay_complete(struct timer_list *t) static void mock_context_unpin(struct intel_context *ce) { mock_timeline_unpin(ce->ring->timeline); - list_del(&ce->active_link); - i915_gem_context_put(ce->gem_context); } static void mock_context_destroy(struct intel_context *ce) -- 2.30.2