diff options
| author | Uros Bizjak <[email protected]> | 2022-08-22 16:38:51 +0200 |
|---|---|---|
| committer | Andrew Morton <[email protected]> | 2022-09-11 21:55:09 -0700 |
| commit | e1d7c7609ae0933b59840390c1b207ac0a925c8b (patch) | |
| tree | 55170982bc11f6e761a136a01649c1ccc5e92d1b /tools/perf/scripts/python | |
| parent | 21490eff121555b123f7088b935e40ee43d2c642 (diff) | |
bitops: use try_cmpxchg in set_mask_bits and bit_clear_unless
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
set_mask_bits and bit_clear_unless. 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, enabling further code simplifications.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Uros Bizjak <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python')
0 files changed, 0 insertions, 0 deletions