diff options
| author | Imran Khan <imran.f.khan@oracle.com> | 2023-03-09 22:09:31 +1100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-29 12:23:45 +0200 |
| commit | c9f2dfb7b59e5a6db054f821a6e1a6db8fa57d64 (patch) | |
| tree | 05c655fea0c99066e83b7593479ccbc6d9e10389 /fs/kernfs/file.c | |
| parent | 9caf696142252a466fb89e629d0eddcdced027b0 (diff) | |
kernfs: Use a per-fs rwsem to protect per-fs list of kernfs_super_info.
Right now per-fs kernfs_rwsem protects list of kernfs_super_info instances
for a kernfs_root. Since kernfs_rwsem is used to synchronize several other
operations across kernfs and since most of these operations don't impact
kernfs_super_info, we can use a separate per-fs rwsem to synchronize access
to list of kernfs_super_info.
This helps in reducing contention around kernfs_rwsem and also allows
operations that change/access list of kernfs_super_info to proceed without
contending for kernfs_rwsem.
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Link: https://lore.kernel.org/r/20230309110932.2889010-3-imran.f.khan@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/kernfs/file.c')
| -rw-r--r-- | fs/kernfs/file.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c index e4a50e4ff0d2..40c4661f15b7 100644 --- a/fs/kernfs/file.c +++ b/fs/kernfs/file.c @@ -922,8 +922,8 @@ repeat: root = kernfs_root(kn); /* kick fsnotify */ - down_write(&root->kernfs_rwsem); + down_read(&root->kernfs_supers_rwsem); list_for_each_entry(info, &kernfs_root(kn)->supers, node) { struct kernfs_node *parent; struct inode *p_inode = NULL; @@ -960,7 +960,7 @@ repeat: iput(inode); } - up_write(&root->kernfs_rwsem); + up_read(&root->kernfs_supers_rwsem); kernfs_put(kn); goto repeat; } |