This is a note to let you know that I've just added the patch titled
dma-fence: Wrap querying the fence->status
to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: dma-fence-wrap-querying-the-fence-status.patch and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From d6c99f4bf093a58d3ab47caaec74b81f18bc4e3f Mon Sep 17 00:00:00 2001
From: Chris Wilson chris@chris-wilson.co.uk Date: Wed, 4 Jan 2017 14:12:21 +0000 Subject: dma-fence: Wrap querying the fence->status
From: Chris Wilson chris@chris-wilson.co.uk
commit d6c99f4bf093a58d3ab47caaec74b81f18bc4e3f upstream.
The fence->status is an optional field that is only valid once the fence has been signaled. (Driver may fill the fence->status with an error code prior to calling dma_fence_signal().) Given the restriction upon its validity, wrap querying of the fence->status into a helper dma_fence_get_status().
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch Reviewed-by: Sumit Semwal sumit.semwal@linaro.org Signed-off-by: Sumit Semwal sumit.semwal@linaro.org Link: http://patchwork.freedesktop.org/patch/msgid/20170104141222.6992-2-chris@chr... [s/dma_fence/fence/g - gregkh] Cc: Jisheng Zhang Jisheng.Zhang@synaptics.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/dma-buf/fence.c | 25 +++++++++++++++++++++++++ drivers/dma-buf/sync_debug.c | 20 ++++++++++---------- drivers/dma-buf/sync_file.c | 6 ++---- include/linux/fence.h | 24 ++++++++++++++++++++++++ 4 files changed, 61 insertions(+), 14 deletions(-)
--- a/drivers/dma-buf/fence.c +++ b/drivers/dma-buf/fence.c @@ -281,6 +281,31 @@ int fence_add_callback(struct fence *fen EXPORT_SYMBOL(fence_add_callback);
/** + * fence_get_status - returns the status upon completion + * @fence: [in] the fence to query + * + * This wraps fence_get_status_locked() to return the error status + * condition on a signaled fence. See fence_get_status_locked() for more + * details. + * + * Returns 0 if the fence has not yet been signaled, 1 if the fence has + * been signaled without an error condition, or a negative error code + * if the fence has been completed in err. + */ +int fence_get_status(struct fence *fence) +{ + unsigned long flags; + int status; + + spin_lock_irqsave(fence->lock, flags); + status = fence_get_status_locked(fence); + spin_unlock_irqrestore(fence->lock, flags); + + return status; +} +EXPORT_SYMBOL(fence_get_status); + +/** * fence_remove_callback - remove a callback from the signaling list * @fence: [in] the fence to wait on * @cb: [in] the callback to remove --- a/drivers/dma-buf/sync_debug.c +++ b/drivers/dma-buf/sync_debug.c @@ -62,29 +62,29 @@ void sync_file_debug_remove(struct sync_
static const char *sync_status_str(int status) { - if (status == 0) - return "signaled"; + if (status < 0) + return "error";
if (status > 0) - return "active"; + return "signaled";
- return "error"; + return "active"; }
-static void sync_print_fence(struct seq_file *s, struct fence *fence, bool show) +static void sync_print_fence(struct seq_file *s, + struct fence *fence, bool show) { - int status = 1; struct sync_timeline *parent = fence_parent(fence); + int status;
- if (fence_is_signaled_locked(fence)) - status = fence->status; + status = fence_get_status_locked(fence);
seq_printf(s, " %s%sfence %s", show ? parent->name : "", show ? "_" : "", sync_status_str(status));
- if (status <= 0) { + if (status) { struct timespec64 ts64 = ktime_to_timespec64(fence->timestamp);
@@ -133,7 +133,7 @@ static void sync_print_sync_file(struct int i;
seq_printf(s, "[%p] %s: %s\n", sync_file, sync_file->name, - sync_status_str(!fence_is_signaled(sync_file->fence))); + sync_status_str(fence_get_status(sync_file->fence)));
if (fence_is_array(sync_file->fence)) { struct fence_array *array = to_fence_array(sync_file->fence); --- a/drivers/dma-buf/sync_file.c +++ b/drivers/dma-buf/sync_file.c @@ -377,10 +377,8 @@ static void sync_fill_fence_info(struct sizeof(info->obj_name)); strlcpy(info->driver_name, fence->ops->get_driver_name(fence), sizeof(info->driver_name)); - if (fence_is_signaled(fence)) - info->status = fence->status >= 0 ? 1 : fence->status; - else - info->status = 0; + + info->status = fence_get_status(fence); info->timestamp_ns = ktime_to_ns(fence->timestamp); }
--- a/include/linux/fence.h +++ b/include/linux/fence.h @@ -334,6 +334,30 @@ static inline struct fence *fence_later( return fence_is_signaled(f2) ? NULL : f2; }
+/** + * fence_get_status_locked - returns the status upon completion + * @fence: [in] the fence to query + * + * Drivers can supply an optional error status condition before they signal + * the fence (to indicate whether the fence was completed due to an error + * rather than success). The value of the status condition is only valid + * if the fence has been signaled, fence_get_status_locked() first checks + * the signal state before reporting the error status. + * + * Returns 0 if the fence has not yet been signaled, 1 if the fence has + * been signaled without an error condition, or a negative error code + * if the fence has been completed in err. + */ +static inline int fence_get_status_locked(struct fence *fence) +{ + if (fence_is_signaled_locked(fence)) + return fence->status < 0 ? fence->status : 1; + else + return 0; +} + +int fence_get_status(struct fence *fence); + signed long fence_wait_timeout(struct fence *, bool intr, signed long timeout); signed long fence_wait_any_timeout(struct fence **fences, uint32_t count, bool intr, signed long timeout);
Patches currently in stable-queue which might be from chris@chris-wilson.co.uk are
queue-4.9/dma-buf-sw-sync-fix-the-is-signaled-test-to-handle-u32-wraparound.patch queue-4.9/dma-fence-clear-fence-status-during-dma_fence_init.patch queue-4.9/dma-buf-sw-sync-fix-locking-around-sync_timeline-lists.patch queue-4.9/dma-fence-wrap-querying-the-fence-status.patch queue-4.9/dma-buf-sw_sync-clean-up-list-before-signaling-the-fence.patch queue-4.9/dma-buf-sw-sync-reduce-irqsave-irqrestore-from-known-context.patch queue-4.9/dma-buf-sw_sync-move-timeline_fence_ops-around.patch queue-4.9/dma-buf-sw-sync-prevent-user-overflow-on-timeline-advance.patch queue-4.9/dma-fence-introduce-drm_fence_set_error-helper.patch queue-4.9/dma-buf-sw_sync-force-signal-all-unsignaled-fences-on-dying-timeline.patch queue-4.9/dma-buf-sw-sync-use-an-rbtree-to-sort-fences-in-the-timeline.patch queue-4.9/dma-buf-sw-sync-sync_pt-is-private-and-of-fixed-size.patch queue-4.9/dma-buf-dma-fence-extract-__dma_fence_is_later.patch