[Intel-gfx] [PATCH 40/43] drm/i915: Move GEM object busy checking to its own file

Chris Wilson chris at chris-wilson.co.uk
Wed Mar 6 14:25:14 UTC 2019


Continuing the decluttering of i915_gem.c by moving the object busy
checking into its own file.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/Makefile            |   1 +
 drivers/gpu/drm/i915/gem/i915_gem_busy.c | 137 +++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_gem.c          | 127 ---------------------
 3 files changed, 138 insertions(+), 127 deletions(-)
 create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_busy.c

diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 2e78fbe79280..50bc8f344000 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -75,6 +75,7 @@ i915-$(CONFIG_DRM_I915_WERROR) += \
 
 # GEM code
 i915-y += \
+	  gem/i915_gem_busy.o \
 	  gem/i915_gem_clflush.o \
 	  gem/i915_gem_context.o \
 	  gem/i915_gem_dmabuf.o \
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_busy.c b/drivers/gpu/drm/i915/gem/i915_gem_busy.c
new file mode 100644
index 000000000000..c06ba7bdf7b0
--- /dev/null
+++ b/drivers/gpu/drm/i915/gem/i915_gem_busy.c
@@ -0,0 +1,137 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2014-2016 Intel Corporation
+ */
+
+#include "i915_gem_ioctls.h"
+#include "i915_gem_object.h"
+
+#include "../intel_ringbuffer.h"
+
+static __always_inline unsigned int __busy_read_flag(unsigned int id)
+{
+	if (id == I915_ENGINE_CLASS_INVALID)
+		return 0xffff0000;
+
+	GEM_BUG_ON(id >= 16);
+	return 0x10000 << id;
+}
+
+static __always_inline unsigned int __busy_write_id(unsigned int id)
+{
+	/*
+	 * The uABI guarantees an active writer is also amongst the read
+	 * engines. This would be true if we accessed the activity tracking
+	 * under the lock, but as we perform the lookup of the object and
+	 * its activity locklessly we can not guarantee that the last_write
+	 * being active implies that we have set the same engine flag from
+	 * last_read - hence we always set both read and write busy for
+	 * last_write.
+	 */
+	if (id == I915_ENGINE_CLASS_INVALID)
+		return 0xffffffff;
+
+	return (id + 1) | __busy_read_flag(id);
+}
+
+static __always_inline unsigned int
+__busy_set_if_active(const struct dma_fence *fence,
+		     unsigned int (*flag)(unsigned int id))
+{
+	const struct i915_request *rq;
+
+	/*
+	 * We have to check the current hw status of the fence as the uABI
+	 * guarantees forward progress. We could rely on the idle worker
+	 * to eventually flush us, but to minimise latency just ask the
+	 * hardware.
+	 *
+	 * Note we only report on the status of native fences.
+	 */
+	if (!dma_fence_is_i915(fence))
+		return 0;
+
+	/* opencode to_request() in order to avoid const warnings */
+	rq = container_of(fence, const struct i915_request, fence);
+	if (i915_request_completed(rq))
+		return 0;
+
+	return flag(rq->engine->uabi_class);
+}
+
+static __always_inline unsigned int
+busy_check_reader(const struct dma_fence *fence)
+{
+	return __busy_set_if_active(fence, __busy_read_flag);
+}
+
+static __always_inline unsigned int
+busy_check_writer(const struct dma_fence *fence)
+{
+	if (!fence)
+		return 0;
+
+	return __busy_set_if_active(fence, __busy_write_id);
+}
+
+int
+i915_gem_busy_ioctl(struct drm_device *dev, void *data,
+		    struct drm_file *file)
+{
+	struct drm_i915_gem_busy *args = data;
+	struct drm_i915_gem_object *obj;
+	struct reservation_object_list *list;
+	unsigned int seq;
+	int err;
+
+	err = -ENOENT;
+	rcu_read_lock();
+	obj = i915_gem_object_lookup_rcu(file, args->handle);
+	if (!obj)
+		goto out;
+
+	/*
+	 * A discrepancy here is that we do not report the status of
+	 * non-i915 fences, i.e. even though we may report the object as idle,
+	 * a call to set-domain may still stall waiting for foreign rendering.
+	 * This also means that wait-ioctl may report an object as busy,
+	 * where busy-ioctl considers it idle.
+	 *
+	 * We trade the ability to warn of foreign fences to report on which
+	 * i915 engines are active for the object.
+	 *
+	 * Alternatively, we can trade that extra information on read/write
+	 * activity with
+	 *	args->busy =
+	 *		!reservation_object_test_signaled_rcu(obj->resv, true);
+	 * to report the overall busyness. This is what the wait-ioctl does.
+	 *
+	 */
+retry:
+	seq = raw_read_seqcount(&obj->resv->seq);
+
+	/* Translate the exclusive fence to the READ *and* WRITE engine */
+	args->busy = busy_check_writer(rcu_dereference(obj->resv->fence_excl));
+
+	/* Translate shared fences to READ set of engines */
+	list = rcu_dereference(obj->resv->fence);
+	if (list) {
+		unsigned int shared_count = list->shared_count, i;
+
+		for (i = 0; i < shared_count; ++i) {
+			struct dma_fence *fence =
+				rcu_dereference(list->shared[i]);
+
+			args->busy |= busy_check_reader(fence);
+		}
+	}
+
+	if (args->busy && read_seqcount_retry(&obj->resv->seq, seq))
+		goto retry;
+
+	err = 0;
+out:
+	rcu_read_unlock();
+	return err;
+}
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 77403a1fba22..49e491275664 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1329,133 +1329,6 @@ i915_gem_object_ggtt_pin(struct drm_i915_gem_object *obj,
 	return vma;
 }
 
-static __always_inline unsigned int __busy_read_flag(unsigned int id)
-{
-	if (id == I915_ENGINE_CLASS_INVALID)
-		return 0xffff0000;
-
-	GEM_BUG_ON(id >= 16);
-	return 0x10000 << id;
-}
-
-static __always_inline unsigned int __busy_write_id(unsigned int id)
-{
-	/*
-	 * The uABI guarantees an active writer is also amongst the read
-	 * engines. This would be true if we accessed the activity tracking
-	 * under the lock, but as we perform the lookup of the object and
-	 * its activity locklessly we can not guarantee that the last_write
-	 * being active implies that we have set the same engine flag from
-	 * last_read - hence we always set both read and write busy for
-	 * last_write.
-	 */
-	if (id == I915_ENGINE_CLASS_INVALID)
-		return 0xffffffff;
-
-	return (id + 1) | __busy_read_flag(id);
-}
-
-static __always_inline unsigned int
-__busy_set_if_active(const struct dma_fence *fence,
-		     unsigned int (*flag)(unsigned int id))
-{
-	const struct i915_request *rq;
-
-	/*
-	 * We have to check the current hw status of the fence as the uABI
-	 * guarantees forward progress. We could rely on the idle worker
-	 * to eventually flush us, but to minimise latency just ask the
-	 * hardware.
-	 *
-	 * Note we only report on the status of native fences.
-	 */
-	if (!dma_fence_is_i915(fence))
-		return 0;
-
-	/* opencode to_request() in order to avoid const warnings */
-	rq = container_of(fence, const struct i915_request, fence);
-	if (i915_request_completed(rq))
-		return 0;
-
-	return flag(rq->engine->uabi_class);
-}
-
-static __always_inline unsigned int
-busy_check_reader(const struct dma_fence *fence)
-{
-	return __busy_set_if_active(fence, __busy_read_flag);
-}
-
-static __always_inline unsigned int
-busy_check_writer(const struct dma_fence *fence)
-{
-	if (!fence)
-		return 0;
-
-	return __busy_set_if_active(fence, __busy_write_id);
-}
-
-int
-i915_gem_busy_ioctl(struct drm_device *dev, void *data,
-		    struct drm_file *file)
-{
-	struct drm_i915_gem_busy *args = data;
-	struct drm_i915_gem_object *obj;
-	struct reservation_object_list *list;
-	unsigned int seq;
-	int err;
-
-	err = -ENOENT;
-	rcu_read_lock();
-	obj = i915_gem_object_lookup_rcu(file, args->handle);
-	if (!obj)
-		goto out;
-
-	/*
-	 * A discrepancy here is that we do not report the status of
-	 * non-i915 fences, i.e. even though we may report the object as idle,
-	 * a call to set-domain may still stall waiting for foreign rendering.
-	 * This also means that wait-ioctl may report an object as busy,
-	 * where busy-ioctl considers it idle.
-	 *
-	 * We trade the ability to warn of foreign fences to report on which
-	 * i915 engines are active for the object.
-	 *
-	 * Alternatively, we can trade that extra information on read/write
-	 * activity with
-	 *	args->busy =
-	 *		!reservation_object_test_signaled_rcu(obj->resv, true);
-	 * to report the overall busyness. This is what the wait-ioctl does.
-	 *
-	 */
-retry:
-	seq = raw_read_seqcount(&obj->resv->seq);
-
-	/* Translate the exclusive fence to the READ *and* WRITE engine */
-	args->busy = busy_check_writer(rcu_dereference(obj->resv->fence_excl));
-
-	/* Translate shared fences to READ set of engines */
-	list = rcu_dereference(obj->resv->fence);
-	if (list) {
-		unsigned int shared_count = list->shared_count, i;
-
-		for (i = 0; i < shared_count; ++i) {
-			struct dma_fence *fence =
-				rcu_dereference(list->shared[i]);
-
-			args->busy |= busy_check_reader(fence);
-		}
-	}
-
-	if (args->busy && read_seqcount_retry(&obj->resv->seq, seq))
-		goto retry;
-
-	err = 0;
-out:
-	rcu_read_unlock();
-	return err;
-}
-
 int
 i915_gem_throttle_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file_priv)
-- 
2.20.1



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