| Message ID | 20191206160428.1503343-1-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] drm/i915: Check for error before calling cmpxchg() | expand |
On Fri, 6 Dec 2019 at 16:04, Chris Wilson <chris@chris-wilson.co.uk> wrote: > > Only do the locked compare of the existing fence->error if we actually > need to set an error. As we tend to call i915_sw_fence_set_error_once() > unconditionally, it saves on typing to put the common has-error check > into the inline. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> For the series: Reviewed-by: Matthew Auld <matthew.auld@intel.com>
diff --git a/drivers/gpu/drm/i915/i915_sw_fence.h b/drivers/gpu/drm/i915/i915_sw_fence.h index 1e90d9a51bd2..19e806ce43bc 100644 --- a/drivers/gpu/drm/i915/i915_sw_fence.h +++ b/drivers/gpu/drm/i915/i915_sw_fence.h @@ -112,7 +112,8 @@ static inline void i915_sw_fence_wait(struct i915_sw_fence *fence) static inline void i915_sw_fence_set_error_once(struct i915_sw_fence *fence, int error) { - cmpxchg(&fence->error, 0, error); + if (unlikely(error)) + cmpxchg(&fence->error, 0, error); } #endif /* _I915_SW_FENCE_H_ */
Only do the locked compare of the existing fence->error if we actually need to set an error. As we tend to call i915_sw_fence_set_error_once() unconditionally, it saves on typing to put the common has-error check into the inline. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/i915_sw_fence.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)