From: Niu Yawei Subject: [PATCH 3/5] quota: simplify remove_inode_dquot_ref() Date: Wed, 04 Jun 2014 12:21:30 +0800 Message-ID: <538E9ECA.3010205@gmail.com> References: <537DD5BA.1050105@gmail.com> <538464AD.6050407@gmail.com> <20140527101219.GA28035@infradead.org> <538541FE.3070203@gmail.com> <20140602083436.GC3224@quack.suse.cz> <538D9AB0.9090607@gmail.com> <20140603154301.GE30706@quack.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Christoph Hellwig , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, yawei.niu@intel.com, andreas.dilger@intel.com, lai.siyao@intel.com To: Jan Kara Return-path: In-Reply-To: <20140603154301.GE30706@quack.suse.cz> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Simplify the remove_inode_dquot_ref() to make it more obvious that now we keep one reference for each dquot from inodes. Signed-off-by: Jan Kara Signed-off-by: Niu Yawei --- fs/quota/dquot.c | 51 +++++++++++++++++++-------------------------------- 1 files changed, 19 insertions(+), 32 deletions(-) diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c index a00201d..51b5763 100644 --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -731,7 +731,6 @@ static struct shrinker dqcache_shrinker = { /* * Put reference to dquot - * NOTE: If you change this function please check whether dqput_blocks() works right... */ void dqput(struct dquot *dquot) { @@ -961,46 +960,34 @@ static void add_dquot_ref(struct super_block *sb, int type) } /* - * Return 0 if dqput() won't block. - * (note that 1 doesn't necessarily mean blocking) - */ -static inline int dqput_blocks(struct dquot *dquot) -{ - if (atomic_read(&dquot->dq_count) <= 1) - return 1; - return 0; -} - -/* * Remove references to dquots from inode and add dquot to list for freeing * if we have the last reference to dquot * We can't race with anybody because we hold dqptr_sem for writing... */ -static int remove_inode_dquot_ref(struct inode *inode, int type, - struct list_head *tofree_head) +static void remove_inode_dquot_ref(struct inode *inode, int type, + struct list_head *tofree_head) { struct dquot *dquot = inode->i_dquot[type]; inode->i_dquot[type] = NULL; - if (dquot) { - if (dqput_blocks(dquot)) { -#ifdef CONFIG_QUOTA_DEBUG - if (atomic_read(&dquot->dq_count) != 1) - quota_error(inode->i_sb, "Adding dquot with " - "dq_count %d to dispose list", - atomic_read(&dquot->dq_count)); -#endif - spin_lock(&dq_list_lock); - /* As dquot must have currently users it can't be on - * the free list... */ - list_add(&dquot->dq_free, tofree_head); - spin_unlock(&dq_list_lock); - return 1; - } - else - dqput(dquot); /* We have guaranteed we won't block */ + if (!dquot) + return; + + if (list_empty(&dquot->dq_free)) { + /* + * The inode still has reference to dquot so it can't be in the + * free list + */ + spin_lock(&dq_list_lock); + list_add(&dquot->dq_free, tofree_head); + spin_unlock(&dq_list_lock); + } else { + /* + * Dquot is already in a list to put so we won't drop the last + * reference here. + */ + dqput(dquot); } - return 0; } /* -- 1.7.1