diff options
| author | Mateusz Guzik <mjguzik@gmail.com> | 2024-08-15 11:33:10 +0300 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2024-08-30 09:22:37 +0300 |
| commit | b381fbbccb4cb60aefa1ab7f8e3766ddb4a461db (patch) | |
| tree | 57edc85b86716eceaa8a68045dd2f142221c2f18 /tools/perf/scripts/python/sched-migration.py | |
| parent | 433f9d76a01056dfeaefc15167b11e514e56f956 (diff) | |
| download | linux-b381fbbccb4cb60aefa1ab7f8e3766ddb4a461db.tar.xz | |
vfs: elide smp_mb in iversion handling in the common case
According to bpftrace on these routines most calls result in cmpxchg,
which already provides the same guarantee.
In inode_maybe_inc_iversion elision is possible because even if the
wrong value was read due to now missing smp_mb fence, the issue is going
to correct itself after cmpxchg. If it appears cmpxchg wont be issued,
the fence + reload are there bringing back previous behavior.
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20240815083310.3865-1-mjguzik@gmail.com
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'tools/perf/scripts/python/sched-migration.py')
0 files changed, 0 insertions, 0 deletions