Commit 1ea06bec authored by Niu Yawei's avatar Niu Yawei Committed by Jan Kara
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quota: avoid unnecessary dqget()/dqput() calls 



Avoid unnecessary dqget()/dqput() calls in __dquot_initialize(),
that will introduce global lock contention otherwise.

Signed-off-by: default avatarLai Siyao <lai.siyao@intel.com>
Signed-off-by: default avatarNiu Yawei <yawei.niu@intel.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent 606cdcca

fs/quota/dquot.c

+14 −1
Original line number Diff line number Diff line
@@ -1402,7 +1402,7 @@ static int dquot_active(const struct inode *inode) 
 */

static void __dquot_initialize(struct inode *inode, int type)

{

	int cnt;

	int cnt, init_needed = 0;

	struct dquot *got[MAXQUOTAS];

	struct super_block *sb = inode->i_sb;

	qsize_t rsv;
@@ -1418,6 +1418,15 @@ static void __dquot_initialize(struct inode *inode, int type) 
		got[cnt] = NULL;

		if (type != -1 && cnt != type)

			continue;

		/*

		 * The i_dquot should have been initialized in most cases,

		 * we check it without locking here to avoid unnecessary

		 * dqget()/dqput() calls.

		 */

		if (inode->i_dquot[cnt])

			continue;

		init_needed = 1;



		switch (cnt) {

		case USRQUOTA:

			qid = make_kqid_uid(inode->i_uid);
@@ -1429,6 +1438,10 @@ static void __dquot_initialize(struct inode *inode, int type) 
		got[cnt] = dqget(sb, qid);

	}



	/* All required i_dquot has been initialized */

	if (!init_needed)

		return;



	down_write(&sb_dqopt(sb)->dqptr_sem);

	if (IS_NOQUOTA(inode))

		goto out_err;