fs: reduce dcache_inode_lock width in lru scanning

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
This commit is contained in:
Nick Piggin 2011-01-07 17:49:46 +11:00
parent 89e6054836
commit be182bff72

View File

@ -621,7 +621,7 @@ static void shrink_dentry_list(struct list_head *list)
dentry = list_entry(list->prev, struct dentry, d_lru);
if (!spin_trylock(&dentry->d_lock)) {
relock:
relock1:
spin_unlock(&dcache_lru_lock);
cpu_relax();
spin_lock(&dcache_lru_lock);
@ -638,20 +638,24 @@ relock:
spin_unlock(&dentry->d_lock);
continue;
}
if (!spin_trylock(&dcache_inode_lock)) {
relock2:
spin_unlock(&dentry->d_lock);
goto relock1;
}
if (IS_ROOT(dentry))
parent = NULL;
else
parent = dentry->d_parent;
if (parent && !spin_trylock(&parent->d_lock)) {
spin_unlock(&dentry->d_lock);
goto relock;
spin_unlock(&dcache_inode_lock);
goto relock2;
}
__dentry_lru_del(dentry);
spin_unlock(&dcache_lru_lock);
prune_one_dentry(dentry, parent);
/* dcache_inode_lock and dentry->d_lock dropped */
spin_lock(&dcache_inode_lock);
spin_lock(&dcache_lru_lock);
}
}
@ -672,7 +676,6 @@ static void __shrink_dcache_sb(struct super_block *sb, int *count, int flags)
LIST_HEAD(tmp);
int cnt = *count;
spin_lock(&dcache_inode_lock);
relock:
spin_lock(&dcache_lru_lock);
while (!list_empty(&sb->s_dentry_lru)) {
@ -711,7 +714,6 @@ relock:
if (!list_empty(&referenced))
list_splice(&referenced, &sb->s_dentry_lru);
spin_unlock(&dcache_lru_lock);
spin_unlock(&dcache_inode_lock);
}
/**
@ -800,14 +802,12 @@ void shrink_dcache_sb(struct super_block *sb)
{
LIST_HEAD(tmp);
spin_lock(&dcache_inode_lock);
spin_lock(&dcache_lru_lock);
while (!list_empty(&sb->s_dentry_lru)) {
list_splice_init(&sb->s_dentry_lru, &tmp);
shrink_dentry_list(&tmp);
}
spin_unlock(&dcache_lru_lock);
spin_unlock(&dcache_inode_lock);
}
EXPORT_SYMBOL(shrink_dcache_sb);