diff options
| author | Ian Kent <raven@themaw.net> | 2021-07-16 11:28:29 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-27 09:29:15 +0200 |
| commit | 7ba0273b2f34a55efe967d3c7381fb1da2ca195f (patch) | |
| tree | b8c0df46d2918cd7fc27c87fa1f9e058bbfd6aeb /fs/kernfs/inode.c | |
| parent | kernfs: use VFS negative dentry caching (diff) | |
| download | linux-7ba0273b2f34a55efe967d3c7381fb1da2ca195f.tar.xz linux-7ba0273b2f34a55efe967d3c7381fb1da2ca195f.zip | |
kernfs: switch kernfs to use an rwsem
The kernfs global lock restricts the ability to perform kernfs node
lookup operations in parallel during path walks.
Change the kernfs mutex to an rwsem so that, when opportunity arises,
node searches can be done in parallel with path walk lookups.
Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Link: https://lore.kernel.org/r/162642770946.63632.2218304587223241374.stgit@web.messagingengine.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/kernfs/inode.c')
| -rw-r--r-- | fs/kernfs/inode.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c index 26f2aa3586f9..dad749f39518 100644 --- a/fs/kernfs/inode.c +++ b/fs/kernfs/inode.c @@ -100,9 +100,9 @@ int kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr) { int ret; - mutex_lock(&kernfs_mutex); + down_write(&kernfs_rwsem); ret = __kernfs_setattr(kn, iattr); - mutex_unlock(&kernfs_mutex); + up_write(&kernfs_rwsem); return ret; } @@ -116,7 +116,7 @@ int kernfs_iop_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, if (!kn) return -EINVAL; - mutex_lock(&kernfs_mutex); + down_write(&kernfs_rwsem); error = setattr_prepare(&init_user_ns, dentry, iattr); if (error) goto out; @@ -129,7 +129,7 @@ int kernfs_iop_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, setattr_copy(&init_user_ns, inode, iattr); out: - mutex_unlock(&kernfs_mutex); + up_write(&kernfs_rwsem); return error; } @@ -185,9 +185,9 @@ int kernfs_iop_getattr(struct user_namespace *mnt_userns, struct inode *inode = d_inode(path->dentry); struct kernfs_node *kn = inode->i_private; - mutex_lock(&kernfs_mutex); + down_write(&kernfs_rwsem); kernfs_refresh_inode(kn, inode); - mutex_unlock(&kernfs_mutex); + up_write(&kernfs_rwsem); generic_fillattr(&init_user_ns, inode, stat); return 0; @@ -278,9 +278,9 @@ int kernfs_iop_permission(struct user_namespace *mnt_userns, kn = inode->i_private; - mutex_lock(&kernfs_mutex); + down_write(&kernfs_rwsem); kernfs_refresh_inode(kn, inode); - mutex_unlock(&kernfs_mutex); + up_write(&kernfs_rwsem); return generic_permission(&init_user_ns, inode, mask); } |