If the expiring_list is empty, we can avoid a costly spinlock in the rcu-walk path through authfs4_d_manage.
Signed-off-by: NeilBrown <[email protected]> --- fs/autofs4/root.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index 1ad119407e2f..774c2dab331b 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -219,6 +219,8 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry, const unsigned char *str = name->name; struct list_head *p, *head; + if (list_empty(&sbi->expiring_list)) + return NULL; spin_lock(&sbi->lookup_lock); head = &sbi->expiring_list; list_for_each(p, head) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
