1. Aug 12, 2023
  2. Aug 10, 2023
    • Uros Bizjak's avatar
      drm/amdgpu: Use local64_try_cmpxchg in amdgpu_perf_read · 9e761bff
      Uros Bizjak authored
      
      
      Use local64_try_cmpxchg instead of local64_cmpxchg (*ptr, old, new) == old
      in amdgpu_perf_read.  x86 CMPXCHG instruction returns success in ZF flag,
      so this change saves a compare after cmpxchg (and related move instruction
      in front of cmpxchg).
      
      Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
      fails. There is no need to re-read the value in the loop.
      
      No functional change intended.
      
      Cc: Alex Deucher <alexander.deucher@amd.com>
      Cc: "Christian König" <christian.koenig@amd.com>
      Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
      Cc: David Airlie <airlied@gmail.com>
      Cc: Daniel Vetter <daniel@ffwll.ch>
      Signed-off-by: default avatarUros Bizjak <ubizjak@gmail.com>
      Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
      9e761bff
  3. Aug 09, 2023