iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fold the call of retain_dentry() into fast_dput()

Browse Source 
Calls of retain_dentry() happen immediately after getting false
from fast_dput() and getting true from retain_dentry() is
treated the same way as non-zero refcount would be treated by
fast_dput() - unlock dentry and bugger off.

Doing that in fast_dput() itself is simpler.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2023-10-31 00:45:40 -04:00
parent 2f42f1eb90
commit f05441c7e1
1 changed files with 4 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
fs/dcache.c
View File

@ -757,6 +757,8 @@ got_locks:
* Try to do a lockless dput(), and return whether that was successful.
*
* If unsuccessful, we return false, having already taken the dentry lock.
* In that case refcount is guaranteed to be zero and we have already
* decided that it's not worth keeping around.
*
* The caller needs to hold the RCU read lock, so that the dentry is
* guaranteed to stay around even if the refcount goes down to zero!
@ -842,7 +844,7 @@ static inline bool fast_dput(struct dentry *dentry)
* don't need to do anything else.
*/
locked:
if (dentry->d_lockref.count) {
if (dentry->d_lockref.count || retain_dentry(dentry)) {
spin_unlock(&dentry->d_lock);
return true;
}
@ -889,12 +891,6 @@ void dput(struct dentry *dentry)
/* Slow case: now with the dentry lock held */
rcu_read_unlock();
if (likely(retain_dentry(dentry))) {
spin_unlock(&dentry->d_lock);
return;
}
dentry->d_lockref.count = 1;
dentry = dentry_kill(dentry);
}
@ -920,8 +916,7 @@ void dput_to_list(struct dentry *dentry, struct list_head *list)
return;
}
rcu_read_unlock();
if (!retain_dentry(dentry))
to_shrink_list(dentry, list);
to_shrink_list(dentry, list);
spin_unlock(&dentry->d_lock);
}