fs: reduce dcache_inode_lock width in lru scanning (be182bff) · Commits · e / devices / android_kernel_fairphone_FP4

fs/dcache.c

+8 −8

Original line number	Diff line number	Diff line
		@@ -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 @@ static void shrink_dentry_list(struct list_head *list)
		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 @@ static void __shrink_dcache_sb(struct super_block sb, int count, int flags)
		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);