Like with the drm-native vblank wait ioctl we can entirely rely on the spinlocks in drm_vblank.c, no need at all to take expensive mutexes. The only reason we had to take mode_config.mutex was to protect the fbdev helper's data-structures, but that's now done by fb_helper->lock.
Cc: John Stultz john.stultz@linaro.org Cc: Thierry Reding treding@nvidia.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com --- drivers/gpu/drm/drm_fb_helper.c | 2 -- 1 file changed, 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 14b3f885a01f..13330c22e6bf 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1342,7 +1342,6 @@ int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd, goto unlock; }
- mutex_lock(&dev->mode_config.mutex); switch (cmd) { case FBIO_WAITFORVSYNC: /* @@ -1382,7 +1381,6 @@ int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd, }
unlock: - mutex_unlock(&dev->mode_config.mutex); mutex_unlock(&fb_helper->lock); return ret; }