From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx> Signalling doesn't need to be enabled at sync_file creation, it is only required if userspace waiting the fence to signal through poll(). Thus we delay fence_add_callback() until poll is called. It only adds the callback the first time poll() is called. This avoid re-adding the same callback multiple times. v2: rebase and update to work with new fence support for sync_file Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx> --- This patch applies on top of my latest sync_file changes to support fence_array: https://lkml.org/lkml/2016/7/4/534 drivers/dma-buf/sync_file.c | 23 ++++++++++++++--------- include/linux/sync_file.h | 2 ++ 2 files changed, 16 insertions(+), 9 deletions(-) diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c index 61a687c..1db4a64 100644 --- a/drivers/dma-buf/sync_file.c +++ b/drivers/dma-buf/sync_file.c @@ -86,8 +86,6 @@ struct sync_file *sync_file_create(struct fence *fence) fence->ops->get_timeline_name(fence), fence->context, fence->seqno); - fence_add_callback(fence, &sync_file->cb, fence_check_cb_func); - return sync_file; } EXPORT_SYMBOL(sync_file_create); @@ -269,9 +267,6 @@ static struct sync_file *sync_file_merge(const char *name, struct sync_file *a, goto err; } - fence_add_callback(sync_file->fence, &sync_file->cb, - fence_check_cb_func); - strlcpy(sync_file->name, name, sizeof(sync_file->name)); return sync_file; @@ -286,7 +281,6 @@ static void sync_file_free(struct kref *kref) struct sync_file *sync_file = container_of(kref, struct sync_file, kref); - fence_remove_callback(sync_file->fence, &sync_file->cb); fence_put(sync_file->fence); kfree(sync_file); } @@ -306,13 +300,24 @@ static unsigned int sync_file_poll(struct file *file, poll_table *wait) poll_wait(file, &sync_file->wq, wait); + if (!sync_file->enabled) { + fence_add_callback(sync_file->fence, &sync_file->cb, + fence_check_cb_func); + sync_file->enabled = true; + } + status = fence_is_signaled(sync_file->fence); - if (status) - return POLLIN; + if (!status) + return 0; + + fence_remove_callback(sync_file->fence, &sync_file->cb); + sync_file->enabled = false; + if (status < 0) return POLLERR; - return 0; + + return POLLIN; } static long sync_file_ioctl_merge(struct sync_file *sync_file, diff --git a/include/linux/sync_file.h b/include/linux/sync_file.h index f7de5a0..16cbafd 100644 --- a/include/linux/sync_file.h +++ b/include/linux/sync_file.h @@ -28,6 +28,7 @@ * @name: name of sync_file. Useful for debugging * @sync_file_list: membership in global file list * @wq: wait queue for fence signaling + * @enabled: wether fence signal is enabled or not * @fence: fence with the fences in the sync_file * @cb: fence callback information */ @@ -40,6 +41,7 @@ struct sync_file { #endif wait_queue_head_t wq; + bool enabled; struct fence *fence; struct fence_cb cb; -- 2.5.5 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
