drm/ttm/amdgpu: consolidate ttm reserve paths (46bca88b) · Commits · 戴 / test

drivers/gpu/drm/amd/amdgpu/amdgpu_object.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -160,7 +160,7 @@ static inline int amdgpu_bo_reserve(struct amdgpu_bo *bo, bool no_intr)
		struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
		int r;

		r = __ttm_bo_reserve(&bo->tbo, !no_intr, false, NULL);
		r = ttm_bo_reserve(&bo->tbo, !no_intr, false, NULL);
		if (unlikely(r != 0)) {
		if (r != -ERESTARTSYS)
		dev_err(adev->dev, "%p reserve failed\n", bo);

drivers/gpu/drm/ttm/ttm_execbuf_util.c

+2 −10

Original line number	Diff line number	Diff line
		@@ -93,7 +93,7 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
		list_for_each_entry(entry, list, head) {
		struct ttm_buffer_object *bo = entry->bo;

		ret = __ttm_bo_reserve(bo, intr, (ticket == NULL), ticket);
		ret = ttm_bo_reserve(bo, intr, (ticket == NULL), ticket);
		if (ret == -EALREADY && dups) {
		struct ttm_validate_buffer *safe = entry;
		entry = list_prev_entry(entry, head);
		@@ -119,13 +119,7 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
		ttm_eu_backoff_reservation_reverse(list, entry);

		if (ret == -EDEADLK) {
		if (intr) {
		ret = dma_resv_lock_slow_interruptible(bo->base.resv,
		ticket);
		} else {
		dma_resv_lock_slow(bo->base.resv, ticket);
		ret = 0;
		}
		ret = ttm_bo_reserve_slowpath(bo, intr, ticket);
		}

		if (!ret && entry->num_shared)
		@@ -133,8 +127,6 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
		entry->num_shared);

		if (unlikely(ret != 0)) {
		if (ret == -EINTR)
		ret = -ERESTARTSYS;
		if (ticket) {
		ww_acquire_done(ticket);
		ww_acquire_fini(ticket);

include/drm/ttm/ttm_bo_driver.h

+17 −74

Original line number	Diff line number	Diff line
		@@ -599,27 +599,28 @@ int ttm_mem_io_lock(struct ttm_mem_type_manager *man, bool interruptible);
		void ttm_mem_io_unlock(struct ttm_mem_type_manager *man);

		/**
		* __ttm_bo_reserve:
		* ttm_bo_reserve:
		*
		* @bo: A pointer to a struct ttm_buffer_object.
		* @interruptible: Sleep interruptible if waiting.
		* @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
		* @ticket: ticket used to acquire the ww_mutex.
		*
		* Will not remove reserved buffers from the lru lists.
		* Otherwise identical to ttm_bo_reserve.
		* Locks a buffer object for validation. (Or prevents other processes from
		* locking it for validation), while taking a number of measures to prevent
		* deadlocks.
		*
		* Returns:
		* -EDEADLK: The reservation may cause a deadlock.
		* Release all buffer reservations, wait for @bo to become unreserved and
		* try again. (only if use_sequence == 1).
		* try again.
		* -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
		* a signal. Release all buffer reservations and return to user-space.
		* -EBUSY: The function needed to sleep, but @no_wait was true
		* -EALREADY: Bo already reserved using @ticket. This error code will only
		* be returned if @use_ticket is set to true.
		*/
		static inline int __ttm_bo_reserve(struct ttm_buffer_object *bo,
		static inline int ttm_bo_reserve(struct ttm_buffer_object *bo,
		bool interruptible, bool no_wait,
		struct ww_acquire_ctx *ticket)
		{
		@@ -643,59 +644,6 @@ static inline int __ttm_bo_reserve(struct ttm_buffer_object *bo,
		return ret;
		}

		/**
		* ttm_bo_reserve:
		*
		* @bo: A pointer to a struct ttm_buffer_object.
		* @interruptible: Sleep interruptible if waiting.
		* @no_wait: Don't sleep while trying to reserve, rather return -EBUSY.
		* @ticket: ticket used to acquire the ww_mutex.
		*
		* Locks a buffer object for validation. (Or prevents other processes from
		* locking it for validation) and removes it from lru lists, while taking
		* a number of measures to prevent deadlocks.
		*
		* Deadlocks may occur when two processes try to reserve multiple buffers in
		* different order, either by will or as a result of a buffer being evicted
		* to make room for a buffer already reserved. (Buffers are reserved before
		* they are evicted). The following algorithm prevents such deadlocks from
		* occurring:
		* Processes attempting to reserve multiple buffers other than for eviction,
		* (typically execbuf), should first obtain a unique 32-bit
		* validation sequence number,
		* and call this function with @use_ticket == 1 and @ticket->stamp == the unique
		* sequence number. If upon call of this function, the buffer object is already
		* reserved, the validation sequence is checked against the validation
		* sequence of the process currently reserving the buffer,
		* and if the current validation sequence is greater than that of the process
		* holding the reservation, the function returns -EDEADLK. Otherwise it sleeps
		* waiting for the buffer to become unreserved, after which it retries
		* reserving.
		* The caller should, when receiving an -EDEADLK error
		* release all its buffer reservations, wait for @bo to become unreserved, and
		* then rerun the validation with the same validation sequence. This procedure
		* will always guarantee that the process with the lowest validation sequence
		* will eventually succeed, preventing both deadlocks and starvation.
		*
		* Returns:
		* -EDEADLK: The reservation may cause a deadlock.
		* Release all buffer reservations, wait for @bo to become unreserved and
		* try again. (only if use_sequence == 1).
		* -ERESTARTSYS: A wait for the buffer to become unreserved was interrupted by
		* a signal. Release all buffer reservations and return to user-space.
		* -EBUSY: The function needed to sleep, but @no_wait was true
		* -EALREADY: Bo already reserved using @ticket. This error code will only
		* be returned if @use_ticket is set to true.
		*/
		static inline int ttm_bo_reserve(struct ttm_buffer_object *bo,
		bool interruptible, bool no_wait,
		struct ww_acquire_ctx *ticket)
		{
		WARN_ON(!kref_read(&bo->kref));

		return __ttm_bo_reserve(bo, interruptible, no_wait, ticket);
		}

		/**
		* ttm_bo_reserve_slowpath:
		* @bo: A pointer to a struct ttm_buffer_object.
		@@ -710,21 +658,16 @@ static inline int ttm_bo_reserve_slowpath(struct ttm_buffer_object *bo,
		bool interruptible,
		struct ww_acquire_ctx *ticket)
		{
		int ret = 0;

		WARN_ON(!kref_read(&bo->kref));

		if (interruptible)
		ret = dma_resv_lock_slow_interruptible(bo->base.resv,
		if (interruptible) {
		int ret = dma_resv_lock_slow_interruptible(bo->base.resv,
		ticket);
		else
		dma_resv_lock_slow(bo->base.resv, ticket);

		if (ret == -EINTR)
		ret = -ERESTARTSYS;

		return ret;
		}
		dma_resv_lock_slow(bo->base.resv, ticket);
		return 0;
		}

		/**
		* ttm_bo_unreserve

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