From d8f2ebaac650dc35db3bf5cf10e8ee1115b455f8 Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Thu, 13 Apr 2017 11:41:38 +1000 Subject: sync_file: get rid of internal reference count. sync_file uses the reference count of the file, the internal kref was never getting moved past 1. We can reintroduce this if we decide we need it later. [airlied: fix buildbot warnings] Reviewed-by: Chris Wilson Signed-off-by: Dave Airlie Acked-by: Sumit Semwal Signed-off-by: Gustavo Padovan Link: http://patchwork.freedesktop.org/patch/msgid/20170413014144.637-2-airlied@gmail.com --- drivers/dma-buf/sync_file.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c index 2321035f6204..dc89b1d484e8 100644 --- a/drivers/dma-buf/sync_file.c +++ b/drivers/dma-buf/sync_file.c @@ -41,8 +41,6 @@ static struct sync_file *sync_file_alloc(void) if (IS_ERR(sync_file->file)) goto err; - kref_init(&sync_file->kref); - init_waitqueue_head(&sync_file->wq); INIT_LIST_HEAD(&sync_file->cb.node); @@ -277,22 +275,15 @@ err: } -static void sync_file_free(struct kref *kref) +static int sync_file_release(struct inode *inode, struct file *file) { - struct sync_file *sync_file = container_of(kref, struct sync_file, - kref); + struct sync_file *sync_file = file->private_data; if (test_bit(POLL_ENABLED, &sync_file->fence->flags)) dma_fence_remove_callback(sync_file->fence, &sync_file->cb); dma_fence_put(sync_file->fence); kfree(sync_file); -} - -static int sync_file_release(struct inode *inode, struct file *file) -{ - struct sync_file *sync_file = file->private_data; - kref_put(&sync_file->kref, sync_file_free); return 0; } -- cgit v1.2.3 From 03c0c5f6641533f5fc14bf4e76d2304197402552 Mon Sep 17 00:00:00 2001 From: Andres Rodriguez Date: Wed, 26 Apr 2017 10:46:20 -0400 Subject: dma-buf: avoid scheduling on fence status query v2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a timeout of zero is specified, the caller is only interested in the fence status. In the current implementation, dma_fence_default_wait will always call schedule_timeout() at least once for an unsignaled fence. This adds a significant overhead to a fence status query. Avoid this overhead by returning early if a zero timeout is specified. v2: move early return after enable_signaling Signed-off-by: Andres Rodriguez Reviewed-by: Christian König Signed-off-by: Gustavo Padovan Link: http://patchwork.freedesktop.org/patch/msgid/20170426144620.3560-1-andresx7@gmail.com --- drivers/dma-buf/dma-fence.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c index 0918d3f003d6..57da14c15987 100644 --- a/drivers/dma-buf/dma-fence.c +++ b/drivers/dma-buf/dma-fence.c @@ -402,6 +402,11 @@ dma_fence_default_wait(struct dma_fence *fence, bool intr, signed long timeout) } } + if (!timeout) { + ret = 0; + goto out; + } + cb.base.func = dma_fence_default_wait_cb; cb.task = current; list_add(&cb.base.node, &fence->cb_list); -- cgit v1.2.3 From 9eddb41dbe98b4854e64a69b686ace734c2c7aa0 Mon Sep 17 00:00:00 2001 From: Markus Elfring Date: Mon, 8 May 2017 10:32:44 +0200 Subject: dma-buf: Combine two function calls into one in dma_buf_debug_show() A bit of data was put into a sequence by two separate function calls. Print the same data by a single function call instead. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring Reviewed-by: Gustavo Padovan Signed-off-by: Sumit Semwal --- drivers/dma-buf/dma-buf.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 512bdbc23bbb..53257c166f4d 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -1122,9 +1122,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused) attach_count = 0; list_for_each_entry(attach_obj, &buf_obj->attachments, node) { - seq_puts(s, "\t"); - - seq_printf(s, "%s\n", dev_name(attach_obj->dev)); + seq_printf(s, "\t%s\n", dev_name(attach_obj->dev)); attach_count++; } -- cgit v1.2.3 From db7942b6292306abd42d3340fdb57d9d80fcffd9 Mon Sep 17 00:00:00 2001 From: Markus Elfring Date: Mon, 8 May 2017 10:50:09 +0200 Subject: dma-buf: Improve a size determination in dma_buf_attach() Replace the specification of a data structure by a pointer dereference as the parameter for the operator "sizeof" to make the corresponding size determination a bit safer according to the Linux coding style convention. Signed-off-by: Markus Elfring Reviewed-by: Gustavo Padovan Signed-off-by: Sumit Semwal --- drivers/dma-buf/dma-buf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 53257c166f4d..9887d72cf804 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -558,7 +558,7 @@ struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, if (WARN_ON(!dmabuf || !dev)) return ERR_PTR(-EINVAL); - attach = kzalloc(sizeof(struct dma_buf_attachment), GFP_KERNEL); + attach = kzalloc(sizeof(*attach), GFP_KERNEL); if (attach == NULL) return ERR_PTR(-ENOMEM); -- cgit v1.2.3 From 34d84ec4881d1343bec8c0848fd946e3073e6612 Mon Sep 17 00:00:00 2001 From: Markus Elfring Date: Mon, 8 May 2017 10:54:17 +0200 Subject: dma-buf: Adjust a null pointer check in dma_buf_attach() The script "checkpatch.pl" pointed information out like the following. Comparison to NULL could be written "!attach" Thus adjust this expression. Signed-off-by: Markus Elfring Reviewed-by: Gustavo Padovan Signed-off-by: Sumit Semwal --- drivers/dma-buf/dma-buf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 9887d72cf804..4a038dcf5361 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -559,7 +559,7 @@ struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, return ERR_PTR(-EINVAL); attach = kzalloc(sizeof(*attach), GFP_KERNEL); - if (attach == NULL) + if (!attach) return ERR_PTR(-ENOMEM); attach->dev = dev; -- cgit v1.2.3 From 47a369deaf31d247bb0074e31ecbccb44e80e542 Mon Sep 17 00:00:00 2001 From: Markus Elfring Date: Mon, 8 May 2017 10:55:42 +0200 Subject: dma-buf: Use seq_putc() in two functions Three single characters (line breaks) should be put into a sequence. Thus use the corresponding function "seq_putc". This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring Reviewed-by: Gustavo Padovan Signed-off-by: Sumit Semwal Link: http://patchwork.freedesktop.org/patch/msgid/b8a85220-039a-e4bb-c74b-d76baab234e8@users.sourceforge.net --- drivers/dma-buf/sync_debug.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/sync_debug.c b/drivers/dma-buf/sync_debug.c index c769dc653b34..a0d780ab68c3 100644 --- a/drivers/dma-buf/sync_debug.c +++ b/drivers/dma-buf/sync_debug.c @@ -110,7 +110,7 @@ static void sync_print_fence(struct seq_file *s, } } - seq_puts(s, "\n"); + seq_putc(s, '\n'); } static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj) @@ -161,7 +161,7 @@ static int sync_debugfs_show(struct seq_file *s, void *unused) sync_timeline_list); sync_print_obj(s, obj); - seq_puts(s, "\n"); + seq_putc(s, '\n'); } spin_unlock_irqrestore(&sync_timeline_list_lock, flags); @@ -173,7 +173,7 @@ static int sync_debugfs_show(struct seq_file *s, void *unused) container_of(pos, struct sync_file, sync_file_list); sync_print_sync_file(s, sync_file); - seq_puts(s, "\n"); + seq_putc(s, '\n'); } spin_unlock_irqrestore(&sync_file_list_lock, flags); return 0; -- cgit v1.2.3 From 71ebc9a3795818eab52e81bbcbdfae130ee35d9e Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 16 May 2017 12:10:42 +0100 Subject: dma-buf/sync-file: Defer creation of sync_file->name Constructing the name takes the majority of the time for allocating a sync_file to wrap a fence, and the name is very rarely used (only via the sync_file status user interface). To reduce the impact on the common path (that of creating sync_file to pass around), defer the construction of the name until it is first used. v2: Update kerneldoc (kbuild test robot) v3: sync_debug.c was peeking at the name v4: Comment upon the potential race between two users of sync_file_get_name() and claim that such a race is below the level of notice. However, to prevent any future nuisance, use a global spinlock to serialize the assignment of the name. v5: Completely avoid the read/write race by only storing the name passed in from the user inside sync_file->user_name and passing in a buffer to dynamically construct the name otherwise. Signed-off-by: Chris Wilson Cc: Sumit Semwal Cc: Gustavo Padovan Cc: Daniel Vetter Cc: David Herrmann Reviewed-by: Daniel Vetter Signed-off-by: Gustavo Padovan Link: http://patchwork.freedesktop.org/patch/msgid/20170516111042.24719-1-chris@chris-wilson.co.uk --- drivers/dma-buf/sync_debug.c | 4 +++- drivers/dma-buf/sync_file.c | 39 ++++++++++++++++++++++++++++++++------- include/linux/sync_file.h | 11 +++++++++-- 3 files changed, 44 insertions(+), 10 deletions(-) (limited to 'drivers/dma-buf') diff --git a/drivers/dma-buf/sync_debug.c b/drivers/dma-buf/sync_debug.c index a0d780ab68c3..82a6e7f6d37f 100644 --- a/drivers/dma-buf/sync_debug.c +++ b/drivers/dma-buf/sync_debug.c @@ -132,9 +132,11 @@ static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj) static void sync_print_sync_file(struct seq_file *s, struct sync_file *sync_file) { + char buf[128]; int i; - seq_printf(s, "[%p] %s: %s\n", sync_file, sync_file->name, + seq_printf(s, "[%p] %s: %s\n", sync_file, + sync_file_get_name(sync_file, buf, sizeof(buf)), sync_status_str(dma_fence_get_status(sync_file->fence))); if (dma_fence_is_array(sync_file->fence)) { diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c index dc89b1d484e8..545e2c5c4815 100644 --- a/drivers/dma-buf/sync_file.c +++ b/drivers/dma-buf/sync_file.c @@ -80,11 +80,6 @@ struct sync_file *sync_file_create(struct dma_fence *fence) sync_file->fence = dma_fence_get(fence); - snprintf(sync_file->name, sizeof(sync_file->name), "%s-%s%llu-%d", - fence->ops->get_driver_name(fence), - fence->ops->get_timeline_name(fence), fence->context, - fence->seqno); - return sync_file; } EXPORT_SYMBOL(sync_file_create); @@ -129,6 +124,36 @@ struct dma_fence *sync_file_get_fence(int fd) } EXPORT_SYMBOL(sync_file_get_fence); +/** + * sync_file_get_name - get the name of the sync_file + * @sync_file: sync_file to get the fence from + * @buf: destination buffer to copy sync_file name into + * @len: available size of destination buffer. + * + * Each sync_file may have a name assigned either by the user (when merging + * sync_files together) or created from the fence it contains. In the latter + * case construction of the name is deferred until use, and so requires + * sync_file_get_name(). + * + * Returns: a string representing the name. + */ +char *sync_file_get_name(struct sync_file *sync_file, char *buf, int len) +{ + if (sync_file->user_name[0]) { + strlcpy(buf, sync_file->user_name, len); + } else { + struct dma_fence *fence = sync_file->fence; + + snprintf(buf, len, "%s-%s%llu-%d", + fence->ops->get_driver_name(fence), + fence->ops->get_timeline_name(fence), + fence->context, + fence->seqno); + } + + return buf; +} + static int sync_file_set_fence(struct sync_file *sync_file, struct dma_fence **fences, int num_fences) { @@ -266,7 +291,7 @@ static struct sync_file *sync_file_merge(const char *name, struct sync_file *a, goto err; } - strlcpy(sync_file->name, name, sizeof(sync_file->name)); + strlcpy(sync_file->user_name, name, sizeof(sync_file->user_name)); return sync_file; err: @@ -413,7 +438,7 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file, } no_fences: - strlcpy(info.name, sync_file->name, sizeof(info.name)); + sync_file_get_name(sync_file, info.name, sizeof(info.name)); info.status = dma_fence_is_signaled(sync_file->fence); info.num_fences = num_fences; diff --git a/include/linux/sync_file.h b/include/linux/sync_file.h index d37beefdfbd5..5726107963b2 100644 --- a/include/linux/sync_file.h +++ b/include/linux/sync_file.h @@ -23,7 +23,6 @@ /** * struct sync_file - sync file to export to the userspace * @file: file representing this fence - * @name: name of sync_file. Useful for debugging * @sync_file_list: membership in global file list * @wq: wait queue for fence signaling * @fence: fence with the fences in the sync_file @@ -31,7 +30,14 @@ */ struct sync_file { struct file *file; - char name[32]; + /** + * @user_name: + * + * Name of the sync file provided by userspace, for merged fences. + * Otherwise generated through driver callbacks (in which case the + * entire array is 0). + */ + char user_name[32]; #ifdef CONFIG_DEBUG_FS struct list_head sync_file_list; #endif @@ -46,5 +52,6 @@ struct sync_file { struct sync_file *sync_file_create(struct dma_fence *fence); struct dma_fence *sync_file_get_fence(int fd); +char *sync_file_get_name(struct sync_file *sync_file, char *buf, int len); #endif /* _LINUX_SYNC_H */ -- cgit v1.2.3