From aec11c8d7cb31c67deeba4c9fe015d09735c6813 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Fri, 3 Sep 2021 11:47:52 -0700 Subject: dma-buf/dma-fence: Add deadline awareness MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a way to hint to the fence signaler of an upcoming deadline, such as vblank, which the fence waiter would prefer not to miss. This is to aid the fence signaler in making power management decisions, like boosting frequency as the deadline approaches and awareness of missing deadlines so that can be factored in to the frequency scaling. v2: Drop dma_fence::deadline and related logic to filter duplicate deadlines, to avoid increasing dma_fence size. The fence-context implementation will need similar logic to track deadlines of all the fences on the same timeline. [ckoenig] v3: Clarify locking wrt. set_deadline callback v4: Clarify in docs comment that this is a hint v5: Drop DMA_FENCE_FLAG_HAS_DEADLINE_BIT. v6: More docs v7: Fix typo, clarify past deadlines Signed-off-by: Rob Clark Reviewed-by: Christian König Acked-by: Pekka Paalanen Reviewed-by: Bagas Sanjaya --- include/linux/dma-fence.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'include') diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h index 775cdc0b4f24..d54b595a0fe0 100644 --- a/include/linux/dma-fence.h +++ b/include/linux/dma-fence.h @@ -257,6 +257,26 @@ struct dma_fence_ops { */ void (*timeline_value_str)(struct dma_fence *fence, char *str, int size); + + /** + * @set_deadline: + * + * Callback to allow a fence waiter to inform the fence signaler of + * an upcoming deadline, such as vblank, by which point the waiter + * would prefer the fence to be signaled by. This is intended to + * give feedback to the fence signaler to aid in power management + * decisions, such as boosting GPU frequency. + * + * This is called without &dma_fence.lock held, it can be called + * multiple times and from any context. Locking is up to the callee + * if it has some state to manage. If multiple deadlines are set, + * the expectation is to track the soonest one. If the deadline is + * before the current time, it should be interpreted as an immediate + * deadline. + * + * This callback is optional. + */ + void (*set_deadline)(struct dma_fence *fence, ktime_t deadline); }; void dma_fence_init(struct dma_fence *fence, const struct dma_fence_ops *ops, @@ -583,6 +603,8 @@ static inline signed long dma_fence_wait(struct dma_fence *fence, bool intr) return ret < 0 ? ret : 0; } +void dma_fence_set_deadline(struct dma_fence *fence, ktime_t deadline); + struct dma_fence *dma_fence_get_stub(void); struct dma_fence *dma_fence_allocate_private_stub(void); u64 dma_fence_context_alloc(unsigned num); -- cgit v1.2.3 From d7d5a21dd6b4706c04fbba5d25db8da5f25aab68 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Sat, 18 Feb 2023 12:35:04 -0800 Subject: dma-buf/dma-resv: Add a way to set fence deadline MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a way to set a deadline on remaining resv fences according to the requested usage. Signed-off-by: Rob Clark Reviewed-by: Christian König --- include/linux/dma-resv.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h index 0637659a702c..8d0e34dad446 100644 --- a/include/linux/dma-resv.h +++ b/include/linux/dma-resv.h @@ -479,6 +479,8 @@ int dma_resv_get_singleton(struct dma_resv *obj, enum dma_resv_usage usage, int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src); long dma_resv_wait_timeout(struct dma_resv *obj, enum dma_resv_usage usage, bool intr, unsigned long timeout); +void dma_resv_set_deadline(struct dma_resv *obj, enum dma_resv_usage usage, + ktime_t deadline); bool dma_resv_test_signaled(struct dma_resv *obj, enum dma_resv_usage usage); void dma_resv_describe(struct dma_resv *obj, struct seq_file *seq); -- cgit v1.2.3 From d71c11cc79d259c059f4ad377c0f930263f77c53 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Tue, 28 Feb 2023 10:10:11 -0800 Subject: dma-buf/sync_file: Surface sync-file uABI We had all of the internal driver APIs, but not the all important userspace uABI, in the dma-buf doc. Fix that. And re-arrange the comments slightly as otherwise the comments for the ioctl nr defines would not show up. v2: Fix docs build warning coming from newly including the uabi header in the docs build Signed-off-by: Rob Clark Acked-by: Pekka Paalanen --- include/uapi/linux/sync_file.h | 37 +++++++++++++++---------------------- 1 file changed, 15 insertions(+), 22 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/sync_file.h b/include/uapi/linux/sync_file.h index ee2dcfb3d660..7e42a5b7558b 100644 --- a/include/uapi/linux/sync_file.h +++ b/include/uapi/linux/sync_file.h @@ -16,12 +16,16 @@ #include /** - * struct sync_merge_data - data passed to merge ioctl + * struct sync_merge_data - SYNC_IOC_MERGE: merge two fences * @name: name of new fence * @fd2: file descriptor of second fence * @fence: returns the fd of the new fence to userspace * @flags: merge_data flags * @pad: padding for 64-bit alignment, should always be zero + * + * Creates a new fence containing copies of the sync_pts in both + * the calling fd and sync_merge_data.fd2. Returns the new fence's + * fd in sync_merge_data.fence */ struct sync_merge_data { char name[32]; @@ -34,8 +38,8 @@ struct sync_merge_data { /** * struct sync_fence_info - detailed fence information * @obj_name: name of parent sync_timeline -* @driver_name: name of driver implementing the parent -* @status: status of the fence 0:active 1:signaled <0:error + * @driver_name: name of driver implementing the parent + * @status: status of the fence 0:active 1:signaled <0:error * @flags: fence_info flags * @timestamp_ns: timestamp of status change in nanoseconds */ @@ -48,14 +52,19 @@ struct sync_fence_info { }; /** - * struct sync_file_info - data returned from fence info ioctl + * struct sync_file_info - SYNC_IOC_FILE_INFO: get detailed information on a sync_file * @name: name of fence * @status: status of fence. 1: signaled 0:active <0:error * @flags: sync_file_info flags * @num_fences number of fences in the sync_file * @pad: padding for 64-bit alignment, should always be zero - * @sync_fence_info: pointer to array of structs sync_fence_info with all + * @sync_fence_info: pointer to array of struct &sync_fence_info with all * fences in the sync_file + * + * Takes a struct sync_file_info. If num_fences is 0, the field is updated + * with the actual number of fences. If num_fences is > 0, the system will + * use the pointer provided on sync_fence_info to return up to num_fences of + * struct sync_fence_info, with detailed fence information. */ struct sync_file_info { char name[32]; @@ -69,30 +78,14 @@ struct sync_file_info { #define SYNC_IOC_MAGIC '>' -/** +/* * Opcodes 0, 1 and 2 were burned during a API change to avoid users of the * old API to get weird errors when trying to handling sync_files. The API * change happened during the de-stage of the Sync Framework when there was * no upstream users available. */ -/** - * DOC: SYNC_IOC_MERGE - merge two fences - * - * Takes a struct sync_merge_data. Creates a new fence containing copies of - * the sync_pts in both the calling fd and sync_merge_data.fd2. Returns the - * new fence's fd in sync_merge_data.fence - */ #define SYNC_IOC_MERGE _IOWR(SYNC_IOC_MAGIC, 3, struct sync_merge_data) - -/** - * DOC: SYNC_IOC_FILE_INFO - get detailed information on a sync_file - * - * Takes a struct sync_file_info. If num_fences is 0, the field is updated - * with the actual number of fences. If num_fences is > 0, the system will - * use the pointer provided on sync_fence_info to return up to num_fences of - * struct sync_fence_info, with detailed fence information. - */ #define SYNC_IOC_FILE_INFO _IOWR(SYNC_IOC_MAGIC, 4, struct sync_file_info) #endif /* _UAPI_LINUX_SYNC_H */ -- cgit v1.2.3 From f3823da7e4ba7d4781375c2bb786a8a78efc6591 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Tue, 21 Sep 2021 09:35:50 -0700 Subject: drm/scheduler: Add fence deadline support As the finished fence is the one that is exposed to userspace, and therefore the one that other operations, like atomic update, would block on, we need to propagate the deadline from from the finished fence to the actual hw fence. v2: Split into drm_sched_fence_set_parent() (ckoenig) v3: Ensure a thread calling drm_sched_fence_set_deadline_finished() sees fence->parent set before drm_sched_fence_set_parent() does this test_bit(DMA_FENCE_FLAG_HAS_DEADLINE_BIT). Signed-off-by: Rob Clark Acked-by: Luben Tuikov --- include/drm/gpu_scheduler.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'include') diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h index 9db9e5e504ee..99584e457153 100644 --- a/include/drm/gpu_scheduler.h +++ b/include/drm/gpu_scheduler.h @@ -41,6 +41,15 @@ */ #define DRM_SCHED_FENCE_DONT_PIPELINE DMA_FENCE_FLAG_USER_BITS +/** + * DRM_SCHED_FENCE_FLAG_HAS_DEADLINE_BIT - A fence deadline hint has been set + * + * Because we could have a deadline hint can be set before the backing hw + * fence is created, we need to keep track of whether a deadline has already + * been set. + */ +#define DRM_SCHED_FENCE_FLAG_HAS_DEADLINE_BIT (DMA_FENCE_FLAG_USER_BITS + 1) + enum dma_resv_usage; struct dma_resv; struct drm_gem_object; @@ -280,6 +289,12 @@ struct drm_sched_fence { */ struct dma_fence finished; + /** + * @deadline: deadline set on &drm_sched_fence.finished which + * potentially needs to be propagated to &drm_sched_fence.parent + */ + ktime_t deadline; + /** * @parent: the fence returned by &drm_sched_backend_ops.run_job * when scheduling the job on hardware. We signal the @@ -568,6 +583,8 @@ void drm_sched_entity_set_priority(struct drm_sched_entity *entity, enum drm_sched_priority priority); bool drm_sched_entity_is_ready(struct drm_sched_entity *entity); +void drm_sched_fence_set_parent(struct drm_sched_fence *s_fence, + struct dma_fence *fence); struct drm_sched_fence *drm_sched_fence_alloc( struct drm_sched_entity *s_entity, void *owner); void drm_sched_fence_init(struct drm_sched_fence *fence, -- cgit v1.2.3 From b2c077d001b612b1f34f7e528b2dc6072bd6794e Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Fri, 3 Sep 2021 11:47:53 -0700 Subject: drm/vblank: Add helper to get next vblank time Will be used in the next commit to set a deadline on fences that an atomic update is waiting on. v2: Calculate time at *start* of vblank period, not end v3: Fix kbuild complaints Signed-off-by: Rob Clark Reviewed-by: Mario Kleiner --- include/drm/drm_vblank.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h index 733a3e2d1d10..7f3957943dd1 100644 --- a/include/drm/drm_vblank.h +++ b/include/drm/drm_vblank.h @@ -230,6 +230,7 @@ bool drm_dev_has_vblank(const struct drm_device *dev); u64 drm_crtc_vblank_count(struct drm_crtc *crtc); u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, ktime_t *vblanktime); +int drm_crtc_next_vblank_start(struct drm_crtc *crtc, ktime_t *vblanktime); void drm_crtc_send_vblank_event(struct drm_crtc *crtc, struct drm_pending_vblank_event *e); void drm_crtc_arm_vblank_event(struct drm_crtc *crtc, -- cgit v1.2.3