[PATCH v5 09/14] drm/syncobj: Add deadline support for syncobj waits

[Rob Clark <robdclark@gmail.com>]

From: Rob Clark <robdclark@chromium.org>

Add a new flag to let userspace provide a deadline as a hint for syncobj
and timeline waits.  This gives a hint to the driver signaling the
backing fences about how soon userspace needs it to compete work, so it
can addjust GPU frequency accordingly.  An immediate deadline can be
given to provide something equivalent to i915 "wait boost".

v2: Use absolute u64 ns value for deadline hint, drop cap and driver
    feature flag in favor of allowing count_handles==0 as a way for
    userspace to probe kernel for support of new flag

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/drm_syncobj.c | 59 +++++++++++++++++++++++++++--------
 include/uapi/drm/drm.h        |  5 +++
 2 files changed, 51 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index 0c2be8360525..4f9c3b3906f1 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -973,7 +973,8 @@ static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
 						  uint32_t count,
 						  uint32_t flags,
 						  signed long timeout,
-						  uint32_t *idx)
+						  uint32_t *idx,
+						  ktime_t *deadline)
 {
 	struct syncobj_wait_entry *entries;
 	struct dma_fence *fence;
@@ -1053,6 +1054,15 @@ static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
 			drm_syncobj_fence_add_wait(syncobjs[i], &entries[i]);
 	}
 
+	if (deadline) {
+		for (i = 0; i < count; ++i) {
+			fence = entries[i].fence;
+			if (!fence)
+				continue;
+			dma_fence_set_deadline(fence, *deadline);
+		}
+	}
+
 	do {
 		set_current_state(TASK_INTERRUPTIBLE);
 
@@ -1151,7 +1161,8 @@ static int drm_syncobj_array_wait(struct drm_device *dev,
 				  struct drm_file *file_private,
 				  struct drm_syncobj_wait *wait,
 				  struct drm_syncobj_timeline_wait *timeline_wait,
-				  struct drm_syncobj **syncobjs, bool timeline)
+				  struct drm_syncobj **syncobjs, bool timeline,
+				  ktime_t *deadline)
 {
 	signed long timeout = 0;
 	uint32_t first = ~0;
@@ -1162,7 +1173,8 @@ static int drm_syncobj_array_wait(struct drm_device *dev,
 							 NULL,
 							 wait->count_handles,
 							 wait->flags,
-							 timeout, &first);
+							 timeout, &first,
+							 deadline);
 		if (timeout < 0)
 			return timeout;
 		wait->first_signaled = first;
@@ -1172,7 +1184,8 @@ static int drm_syncobj_array_wait(struct drm_device *dev,
 							 u64_to_user_ptr(timeline_wait->points),
 							 timeline_wait->count_handles,
 							 timeline_wait->flags,
-							 timeout, &first);
+							 timeout, &first,
+							 deadline);
 		if (timeout < 0)
 			return timeout;
 		timeline_wait->first_signaled = first;
@@ -1243,17 +1256,22 @@ drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
 {
 	struct drm_syncobj_wait *args = data;
 	struct drm_syncobj **syncobjs;
+	unsigned possible_flags;
+	ktime_t t, *tp = NULL;
 	int ret = 0;
 
 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 		return -EOPNOTSUPP;
 
-	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
-			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
+	possible_flags = DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
+			 DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
+			 DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE;
+
+	if (args->flags & ~possible_flags)
 		return -EINVAL;
 
 	if (args->count_handles == 0)
-		return -EINVAL;
+		return 0;
 
 	ret = drm_syncobj_array_find(file_private,
 				     u64_to_user_ptr(args->handles),
@@ -1262,8 +1280,13 @@ drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
 	if (ret < 0)
 		return ret;
 
+	if (args->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE) {
+		t = ns_to_ktime(args->deadline_ns);
+		tp = &t;
+	}
+
 	ret = drm_syncobj_array_wait(dev, file_private,
-				     args, NULL, syncobjs, false);
+				     args, NULL, syncobjs, false, tp);
 
 	drm_syncobj_array_free(syncobjs, args->count_handles);
 
@@ -1276,18 +1299,23 @@ drm_syncobj_timeline_wait_ioctl(struct drm_device *dev, void *data,
 {
 	struct drm_syncobj_timeline_wait *args = data;
 	struct drm_syncobj **syncobjs;
+	unsigned possible_flags;
+	ktime_t t, *tp = NULL;
 	int ret = 0;
 
 	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
 		return -EOPNOTSUPP;
 
-	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
-			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
-			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE))
+	possible_flags = DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
+			 DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
+			 DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE |
+			 DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE;
+
+	if (args->flags & ~possible_flags)
 		return -EINVAL;
 
 	if (args->count_handles == 0)
-		return -EINVAL;
+		return -0;
 
 	ret = drm_syncobj_array_find(file_private,
 				     u64_to_user_ptr(args->handles),
@@ -1296,8 +1324,13 @@ drm_syncobj_timeline_wait_ioctl(struct drm_device *dev, void *data,
 	if (ret < 0)
 		return ret;
 
+	if (args->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE) {
+		t = ns_to_ktime(args->deadline_ns);
+		tp = &t;
+	}
+
 	ret = drm_syncobj_array_wait(dev, file_private,
-				     NULL, args, syncobjs, true);
+				     NULL, args, syncobjs, true, tp);
 
 	drm_syncobj_array_free(syncobjs, args->count_handles);
 
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index 642808520d92..aefc8cc743e0 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -887,6 +887,7 @@ struct drm_syncobj_transfer {
 #define DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL (1 << 0)
 #define DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT (1 << 1)
 #define DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE (1 << 2) /* wait for time point to become available */
+#define DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE (1 << 3) /* set fence deadline based to deadline_nsec/sec */
 struct drm_syncobj_wait {
 	__u64 handles;
 	/* absolute timeout */
@@ -895,6 +896,8 @@ struct drm_syncobj_wait {
 	__u32 flags;
 	__u32 first_signaled; /* only valid when not waiting all */
 	__u32 pad;
+	/* Deadline hint to set on backing fence(s) in CLOCK_MONOTONIC: */
+	__u64 deadline_ns;
 };
 
 struct drm_syncobj_timeline_wait {
@@ -907,6 +910,8 @@ struct drm_syncobj_timeline_wait {
 	__u32 flags;
 	__u32 first_signaled; /* only valid when not waiting all */
 	__u32 pad;
+	/* Deadline hint to set on backing fence(s) in CLOCK_MONOTONIC: */
+	__u64 deadline_ns;
 };
 
 
-- 
2.39.1