From: Grigori Goronzy Date: Thu, 2 Jul 2015 23:54:10 +0000 (+0200) Subject: drm/radeon: use RCU query for GEM_BUSY syscall X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=828202a382a06eda74202d4888d01a1078c68922;p=deliverable%2Flinux.git drm/radeon: use RCU query for GEM_BUSY syscall We don't need to call the (expensive) radeon_bo_wait, checking the fences via RCU is much faster. The reservation done by radeon_bo_wait does not save us from any race conditions. Reviewed-by: Christian König Signed-off-by: Grigori Goronzy Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c index ac3c1310b953..7199e19eb8ba 100644 --- a/drivers/gpu/drm/radeon/radeon_gem.c +++ b/drivers/gpu/drm/radeon/radeon_gem.c @@ -428,7 +428,6 @@ int radeon_gem_mmap_ioctl(struct drm_device *dev, void *data, int radeon_gem_busy_ioctl(struct drm_device *dev, void *data, struct drm_file *filp) { - struct radeon_device *rdev = dev->dev_private; struct drm_radeon_gem_busy *args = data; struct drm_gem_object *gobj; struct radeon_bo *robj; @@ -440,10 +439,16 @@ int radeon_gem_busy_ioctl(struct drm_device *dev, void *data, return -ENOENT; } robj = gem_to_radeon_bo(gobj); - r = radeon_bo_wait(robj, &cur_placement, true); + + r = reservation_object_test_signaled_rcu(robj->tbo.resv, true); + if (r == 0) + r = -EBUSY; + else + r = 0; + + cur_placement = ACCESS_ONCE(robj->tbo.mem.mem_type); args->domain = radeon_mem_type_to_domain(cur_placement); drm_gem_object_unreference_unlocked(gobj); - r = radeon_gem_handle_lockup(rdev, r); return r; }