Merge "drm/msm/sde: avoid spinlock recursion in sde fence" into msm-4.9 (f1ac0d4f) · Commits · e / devices / android_kernel_fairphone_FP3

drivers/gpu/drm/msm/sde/sde_fence.c

+31 −23

Original line number	Diff line number	Diff line
		@@ -139,10 +139,9 @@ static void sde_fence_release(struct fence *fence)
		struct sde_fence *f = to_sde_fence(fence);
		struct sde_fence fc, next;
		struct sde_fence_context *ctx = f->ctx;
		unsigned long flags;
		bool release_kref = false;

		spin_lock_irqsave(&ctx->lock, flags);
		spin_lock(&ctx->list_lock);
		list_for_each_entry_safe(fc, next, &ctx->fence_list_head,
		fence_list) {
		/* fence release called before signal */
		@@ -152,7 +151,7 @@ static void sde_fence_release(struct fence *fence)
		break;
		}
		}
		spin_unlock_irqrestore(&ctx->lock, flags);
		spin_unlock(&ctx->list_lock);

		/* keep kput outside spin_lock because it may release ctx */
		if (release_kref)
		@@ -198,7 +197,6 @@ static int _sde_fence_create_fd(void *fence_ctx, uint32_t val)
		struct sync_file *sync_file;
		signed int fd = -EINVAL;
		struct sde_fence_context *ctx = fence_ctx;
		unsigned long flags;

		if (!ctx) {
		SDE_ERROR("invalid context\n");
		@@ -234,12 +232,12 @@ static int _sde_fence_create_fd(void *fence_ctx, uint32_t val)

		fd_install(fd, sync_file->file);

		spin_lock_irqsave(&ctx->lock, flags);
		spin_lock(&ctx->list_lock);
		sde_fence->ctx = fence_ctx;
		sde_fence->fd = fd;
		list_add_tail(&sde_fence->fence_list, &ctx->fence_list_head);
		kref_get(&ctx->kref);
		spin_unlock_irqrestore(&ctx->lock, flags);
		spin_unlock(&ctx->list_lock);
		exit:
		return fd;
		}
		@@ -260,6 +258,7 @@ int sde_fence_init(struct sde_fence_context *ctx,
		ctx->context = fence_context_alloc(1);

		spin_lock_init(&ctx->lock);
		spin_lock_init(&ctx->list_lock);
		INIT_LIST_HEAD(&ctx->fence_list_head);

		return 0;
		@@ -333,7 +332,8 @@ void sde_fence_signal(struct sde_fence_context *ctx, bool is_error)
		{
		unsigned long flags;
		struct sde_fence fc, next;
		uint32_t count = 0;
		bool is_signaled = false;
		struct list_head local_list_head;

		if (!ctx) {
		SDE_ERROR("invalid ctx, %pK\n", ctx);
		@@ -342,37 +342,45 @@ void sde_fence_signal(struct sde_fence_context *ctx, bool is_error)
		return;
		}

		INIT_LIST_HEAD(&local_list_head);

		spin_lock_irqsave(&ctx->lock, flags);
		if ((int)(ctx->done_count - ctx->commit_count) < 0) {
		++ctx->done_count;
		SDE_DEBUG("fence_signal:done count:%d commit count:%d\n",
		ctx->commit_count, ctx->done_count);
		} else {
		SDE_ERROR("extra signal attempt! done count:%d commit:%d\n",
		ctx->done_count, ctx->commit_count);
		goto end;
		spin_unlock_irqrestore(&ctx->lock, flags);
		return;
		}
		spin_unlock_irqrestore(&ctx->lock, flags);

		spin_lock(&ctx->list_lock);
		if (list_empty(&ctx->fence_list_head)) {
		SDE_DEBUG("nothing to trigger!-no get_prop call\n");
		goto end;
		spin_unlock(&ctx->list_lock);
		return;
		}

		SDE_DEBUG("fence_signal:done count:%d commit count:%d\n",
		ctx->commit_count, ctx->done_count);
		list_for_each_entry_safe(fc, next, &ctx->fence_list_head, fence_list)
		list_move(&fc->fence_list, &local_list_head);
		spin_unlock(&ctx->list_lock);

		list_for_each_entry_safe(fc, next, &ctx->fence_list_head,
		fence_list) {
		if (fence_is_signaled_locked(&fc->base)) {
		list_del_init(&fc->fence_list);
		count++;
		list_for_each_entry_safe(fc, next, &local_list_head, fence_list) {
		spin_lock_irqsave(&ctx->lock, flags);
		is_signaled = fence_signal_locked(&fc->base);
		spin_unlock_irqrestore(&ctx->lock, flags);

		if (is_signaled) {
		kref_put(&ctx->kref, sde_fence_destroy);
		} else {
		spin_lock(&ctx->list_lock);
		list_move(&fc->fence_list, &ctx->fence_list_head);
		spin_unlock(&ctx->list_lock);
		}
		}

		SDE_EVT32(ctx->drm_id, ctx->done_count);

		end:
		spin_unlock_irqrestore(&ctx->lock, flags);

		/* keep this outside spin_lock because same ctx may be released */
		for (; count > 0; count--)
		kref_put(&ctx->kref, sde_fence_destroy);
		}

drivers/gpu/drm/msm/sde/sde_fence.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -29,7 +29,8 @@
		* @done_count: Number of completed commits since bootup
		* @drm_id: ID number of owning DRM Object
		* @ref: kref counter on timeline
		* @lock: spinlock for timeline and fence counter protection
		* @lock: spinlock for fence counter protection
		* @list_lock: spinlock for timeline protection
		* @context: fence context
		* @list_head: fence list to hold all the fence created on this context
		* @name: name of fence context/timeline
		@@ -40,6 +41,7 @@ struct sde_fence_context {
		uint32_t drm_id;
		struct kref kref;
		spinlock_t lock;
		spinlock_t list_lock;
		u64 context;
		struct list_head fence_list_head;
		char name[SDE_FENCE_NAME_SIZE];