| Message ID | 20190301140404.26690-2-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/38] drm/i915/execlists: Suppress redundant preemption | expand |
On 01/03/2019 14:03, Chris Wilson wrote: > A simple mutex used for guarding the flow of requests in and out of the > timeline. In the short-term, it will be used only to guard the addition > of requests into the timeline, taken on alloc and released on commit so > that only one caller can construct a request into the timeline > (important as the seqno and ring pointers must be serialised). This will > be used by observers to ensure that the seqno/hwsp is stable. Later, > when we have reduced retiring to only operate on a single timeline at a > time, we can then use the mutex as the sole guard required for retiring. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > --- > drivers/gpu/drm/i915/i915_request.c | 6 +++++- > drivers/gpu/drm/i915/i915_timeline.c | 1 + > drivers/gpu/drm/i915/i915_timeline.h | 2 ++ > drivers/gpu/drm/i915/selftests/i915_request.c | 4 +--- > drivers/gpu/drm/i915/selftests/mock_timeline.c | 1 + > 5 files changed, 10 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c > index c65f6c990fdd..719d1a5ab082 100644 > --- a/drivers/gpu/drm/i915/i915_request.c > +++ b/drivers/gpu/drm/i915/i915_request.c > @@ -563,6 +563,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) > return ERR_CAST(ce); > > reserve_gt(i915); > + mutex_lock(&ce->ring->timeline->mutex); > > /* Move our oldest request to the slab-cache (if not in use!) */ > rq = list_first_entry(&ce->ring->request_list, typeof(*rq), ring_link); > @@ -688,6 +689,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) > > kmem_cache_free(global.slab_requests, rq); > err_unreserve: > + mutex_unlock(&ce->ring->timeline->mutex); > unreserve_gt(i915); > intel_context_unpin(ce); > return ERR_PTR(ret); > @@ -880,7 +882,7 @@ void i915_request_add(struct i915_request *request) > GEM_TRACE("%s fence %llx:%lld\n", > engine->name, request->fence.context, request->fence.seqno); > > - lockdep_assert_held(&request->i915->drm.struct_mutex); > + lockdep_assert_held(&request->timeline->mutex); > trace_i915_request_add(request); > > /* > @@ -991,6 +993,8 @@ void i915_request_add(struct i915_request *request) > */ > if (prev && i915_request_completed(prev)) > i915_request_retire_upto(prev); > + > + mutex_unlock(&request->timeline->mutex); > } > > static unsigned long local_clock_us(unsigned int *cpu) > diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c > index b2202d2e58a2..87a80558da28 100644 > --- a/drivers/gpu/drm/i915/i915_timeline.c > +++ b/drivers/gpu/drm/i915/i915_timeline.c > @@ -162,6 +162,7 @@ int i915_timeline_init(struct drm_i915_private *i915, > timeline->fence_context = dma_fence_context_alloc(1); > > spin_lock_init(&timeline->lock); > + mutex_init(&timeline->mutex); > > INIT_ACTIVE_REQUEST(&timeline->barrier); > INIT_ACTIVE_REQUEST(&timeline->last_request); > diff --git a/drivers/gpu/drm/i915/i915_timeline.h b/drivers/gpu/drm/i915/i915_timeline.h > index 7bec7d2e45bf..36c3849f7108 100644 > --- a/drivers/gpu/drm/i915/i915_timeline.h > +++ b/drivers/gpu/drm/i915/i915_timeline.h > @@ -44,6 +44,8 @@ struct i915_timeline { > #define TIMELINE_CLIENT 0 /* default subclass */ > #define TIMELINE_ENGINE 1 > > + struct mutex mutex; /* protects the flow of requests */ > + > unsigned int pin_count; > const u32 *hwsp_seqno; > struct i915_vma *hwsp_ggtt; > diff --git a/drivers/gpu/drm/i915/selftests/i915_request.c b/drivers/gpu/drm/i915/selftests/i915_request.c > index 7da52e3d67af..7e1b65b8eb19 100644 > --- a/drivers/gpu/drm/i915/selftests/i915_request.c > +++ b/drivers/gpu/drm/i915/selftests/i915_request.c > @@ -141,14 +141,12 @@ static int igt_fence_wait(void *arg) > err = -ENOMEM; > goto out_locked; > } > - mutex_unlock(&i915->drm.struct_mutex); /* safe as we are single user */ > > if (dma_fence_wait_timeout(&request->fence, false, T) != -ETIME) { > pr_err("fence wait success before submit (expected timeout)!\n"); > - goto out_device; > + goto out_locked; > } > > - mutex_lock(&i915->drm.struct_mutex); > i915_request_add(request); > mutex_unlock(&i915->drm.struct_mutex); > > diff --git a/drivers/gpu/drm/i915/selftests/mock_timeline.c b/drivers/gpu/drm/i915/selftests/mock_timeline.c > index d2de9ece2118..416d85233263 100644 > --- a/drivers/gpu/drm/i915/selftests/mock_timeline.c > +++ b/drivers/gpu/drm/i915/selftests/mock_timeline.c > @@ -14,6 +14,7 @@ void mock_timeline_init(struct i915_timeline *timeline, u64 context) > timeline->fence_context = context; > > spin_lock_init(&timeline->lock); > + mutex_init(&timeline->mutex); > > INIT_ACTIVE_REQUEST(&timeline->barrier); > INIT_ACTIVE_REQUEST(&timeline->last_request); > Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Regards, Tvrtko
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index c65f6c990fdd..719d1a5ab082 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -563,6 +563,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) return ERR_CAST(ce); reserve_gt(i915); + mutex_lock(&ce->ring->timeline->mutex); /* Move our oldest request to the slab-cache (if not in use!) */ rq = list_first_entry(&ce->ring->request_list, typeof(*rq), ring_link); @@ -688,6 +689,7 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) kmem_cache_free(global.slab_requests, rq); err_unreserve: + mutex_unlock(&ce->ring->timeline->mutex); unreserve_gt(i915); intel_context_unpin(ce); return ERR_PTR(ret); @@ -880,7 +882,7 @@ void i915_request_add(struct i915_request *request) GEM_TRACE("%s fence %llx:%lld\n", engine->name, request->fence.context, request->fence.seqno); - lockdep_assert_held(&request->i915->drm.struct_mutex); + lockdep_assert_held(&request->timeline->mutex); trace_i915_request_add(request); /* @@ -991,6 +993,8 @@ void i915_request_add(struct i915_request *request) */ if (prev && i915_request_completed(prev)) i915_request_retire_upto(prev); + + mutex_unlock(&request->timeline->mutex); } static unsigned long local_clock_us(unsigned int *cpu) diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c index b2202d2e58a2..87a80558da28 100644 --- a/drivers/gpu/drm/i915/i915_timeline.c +++ b/drivers/gpu/drm/i915/i915_timeline.c @@ -162,6 +162,7 @@ int i915_timeline_init(struct drm_i915_private *i915, timeline->fence_context = dma_fence_context_alloc(1); spin_lock_init(&timeline->lock); + mutex_init(&timeline->mutex); INIT_ACTIVE_REQUEST(&timeline->barrier); INIT_ACTIVE_REQUEST(&timeline->last_request); diff --git a/drivers/gpu/drm/i915/i915_timeline.h b/drivers/gpu/drm/i915/i915_timeline.h index 7bec7d2e45bf..36c3849f7108 100644 --- a/drivers/gpu/drm/i915/i915_timeline.h +++ b/drivers/gpu/drm/i915/i915_timeline.h @@ -44,6 +44,8 @@ struct i915_timeline { #define TIMELINE_CLIENT 0 /* default subclass */ #define TIMELINE_ENGINE 1 + struct mutex mutex; /* protects the flow of requests */ + unsigned int pin_count; const u32 *hwsp_seqno; struct i915_vma *hwsp_ggtt; diff --git a/drivers/gpu/drm/i915/selftests/i915_request.c b/drivers/gpu/drm/i915/selftests/i915_request.c index 7da52e3d67af..7e1b65b8eb19 100644 --- a/drivers/gpu/drm/i915/selftests/i915_request.c +++ b/drivers/gpu/drm/i915/selftests/i915_request.c @@ -141,14 +141,12 @@ static int igt_fence_wait(void *arg) err = -ENOMEM; goto out_locked; } - mutex_unlock(&i915->drm.struct_mutex); /* safe as we are single user */ if (dma_fence_wait_timeout(&request->fence, false, T) != -ETIME) { pr_err("fence wait success before submit (expected timeout)!\n"); - goto out_device; + goto out_locked; } - mutex_lock(&i915->drm.struct_mutex); i915_request_add(request); mutex_unlock(&i915->drm.struct_mutex); diff --git a/drivers/gpu/drm/i915/selftests/mock_timeline.c b/drivers/gpu/drm/i915/selftests/mock_timeline.c index d2de9ece2118..416d85233263 100644 --- a/drivers/gpu/drm/i915/selftests/mock_timeline.c +++ b/drivers/gpu/drm/i915/selftests/mock_timeline.c @@ -14,6 +14,7 @@ void mock_timeline_init(struct i915_timeline *timeline, u64 context) timeline->fence_context = context; spin_lock_init(&timeline->lock); + mutex_init(&timeline->mutex); INIT_ACTIVE_REQUEST(&timeline->barrier); INIT_ACTIVE_REQUEST(&timeline->last_request);
A simple mutex used for guarding the flow of requests in and out of the timeline. In the short-term, it will be used only to guard the addition of requests into the timeline, taken on alloc and released on commit so that only one caller can construct a request into the timeline (important as the seqno and ring pointers must be serialised). This will be used by observers to ensure that the seqno/hwsp is stable. Later, when we have reduced retiring to only operate on a single timeline at a time, we can then use the mutex as the sole guard required for retiring. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/i915_request.c | 6 +++++- drivers/gpu/drm/i915/i915_timeline.c | 1 + drivers/gpu/drm/i915/i915_timeline.h | 2 ++ drivers/gpu/drm/i915/selftests/i915_request.c | 4 +--- drivers/gpu/drm/i915/selftests/mock_timeline.c | 1 + 5 files changed, 10 insertions(+), 4 deletions(-)