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| author | Chris Wilson <chris@chris-wilson.co.uk> | 2017-05-16 14:10:42 +0300 |
|---|---|---|
| committer | Gustavo Padovan <gustavo.padovan@collabora.com> | 2017-05-24 19:08:29 +0300 |
| commit | 71ebc9a3795818eab52e81bbcbdfae130ee35d9e (patch) | |
| tree | 471cdf0619cc75a44a992c0916beb498b3c894d9 /drivers/dma-buf/sync_debug.c | |
| parent | c16f291dee8b7dc28d4bd0f395ccecf3f898cd21 (diff) | |
| download | linux-71ebc9a3795818eab52e81bbcbdfae130ee35d9e.tar.xz | |
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 <chris@chris-wilson.co.uk>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170516111042.24719-1-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/dma-buf/sync_debug.c')
| -rw-r--r-- | drivers/dma-buf/sync_debug.c | 4 |
1 files changed, 3 insertions, 1 deletions
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)) { |