Commit 5bcd3b6f authored by Konstantin Khlebnikov's avatar Konstantin Khlebnikov Committed by Jan Kara
Browse files

quota: optimize i_dquot access 



Remove redundant calls of i_dquot(), keep pointer in local variable.

add/remove: 0/0 grow/shrink: 3/7 up/down: 40/-278 (-238)
function                                     old     new   delta
__dquot_free_space                           734     750     +16
__dquot_alloc_space                          484     500     +16
dquot_free_inode                             324     332      +8
dquot_drop                                    82      69     -13
vfs_load_quota_inode                        1357    1341     -16
dquot_reclaim_space_nodirty                  348     316     -32
dquot_disable                               1980    1944     -36
dquot_claim_space_nodirty                    354     314     -40
__dquot_drop                                 125      83     -42
__dquot_initialize                           522     423     -99

Signed-off-by: default avatarKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent 023a6007

fs/quota/dquot.c

+39 −24
Original line number Diff line number Diff line
@@ -900,14 +900,17 @@ static inline struct dquot **i_dquot(struct inode *inode) 


static int dqinit_needed(struct inode *inode, int type)

{

	struct dquot * const *dquots;

	int cnt;



	if (IS_NOQUOTA(inode))

		return 0;



	dquots = i_dquot(inode);

	if (type != -1)

		return !i_dquot(inode)[type];

		return !dquots[type];

	for (cnt = 0; cnt < MAXQUOTAS; cnt++)

		if (!i_dquot(inode)[cnt])

		if (!dquots[cnt])

			return 1;

	return 0;

}
@@ -970,12 +973,13 @@ static void add_dquot_ref(struct super_block *sb, int type) 
static void remove_inode_dquot_ref(struct inode *inode, int type,

				   struct list_head *tofree_head)

{

	struct dquot *dquot = i_dquot(inode)[type];

	struct dquot **dquots = i_dquot(inode);

	struct dquot *dquot = dquots[type];



	i_dquot(inode)[type] = NULL;

	if (!dquot)

		return;



	dquots[type] = NULL;

	if (list_empty(&dquot->dq_free)) {

		/*

		 * The inode still has reference to dquot so it can't be in the
@@ -1389,13 +1393,15 @@ static int dquot_active(const struct inode *inode) 
static void __dquot_initialize(struct inode *inode, int type)

{

	int cnt, init_needed = 0;

	struct dquot *got[MAXQUOTAS];

	struct dquot **dquots, *got[MAXQUOTAS];

	struct super_block *sb = inode->i_sb;

	qsize_t rsv;



	if (!dquot_active(inode))

		return;



	dquots = i_dquot(inode);



	/* First get references to structures we might need. */

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		struct kqid qid;
@@ -1407,7 +1413,7 @@ static void __dquot_initialize(struct inode *inode, int type) 
		 * we check it without locking here to avoid unnecessary

		 * dqget()/dqput() calls.

		 */

		if (i_dquot(inode)[cnt])

		if (dquots[cnt])

			continue;

		init_needed = 1;
@@ -1438,8 +1444,8 @@ static void __dquot_initialize(struct inode *inode, int type) 
		/* We could race with quotaon or dqget() could have failed */

		if (!got[cnt])

			continue;

		if (!i_dquot(inode)[cnt]) {

			i_dquot(inode)[cnt] = got[cnt];

		if (!dquots[cnt]) {

			dquots[cnt] = got[cnt];

			got[cnt] = NULL;

			/*

			 * Make quota reservation system happy if someone
@@ -1447,7 +1453,7 @@ static void __dquot_initialize(struct inode *inode, int type) 
			 */

			rsv = inode_get_rsv_space(inode);

			if (unlikely(rsv))

				dquot_resv_space(i_dquot(inode)[cnt], rsv);

				dquot_resv_space(dquots[cnt], rsv);

		}

	}

out_err:
@@ -1473,12 +1479,13 @@ EXPORT_SYMBOL(dquot_initialize); 
static void __dquot_drop(struct inode *inode)

{

	int cnt;

	struct dquot **dquots = i_dquot(inode);

	struct dquot *put[MAXQUOTAS];



	spin_lock(&dq_data_lock);

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		put[cnt] = i_dquot(inode)[cnt];

		i_dquot(inode)[cnt] = NULL;

		put[cnt] = dquots[cnt];

		dquots[cnt] = NULL;

	}

	spin_unlock(&dq_data_lock);

	dqput_all(put);
@@ -1486,6 +1493,7 @@ static void __dquot_drop(struct inode *inode) 


void dquot_drop(struct inode *inode)

{

	struct dquot * const *dquots;

	int cnt;



	if (IS_NOQUOTA(inode))
@@ -1498,8 +1506,9 @@ void dquot_drop(struct inode *inode) 
	 * must assure that nobody can come after the DQUOT_DROP and

	 * add quota pointers back anyway.

	 */

	dquots = i_dquot(inode);

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		if (i_dquot(inode)[cnt])

		if (dquots[cnt])

			break;

	}
@@ -1600,8 +1609,8 @@ int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 
{

	int cnt, ret = 0, index;

	struct dquot_warn warn[MAXQUOTAS];

	struct dquot **dquots = i_dquot(inode);

	int reserve = flags & DQUOT_SPACE_RESERVE;

	struct dquot **dquots;



	if (!dquot_active(inode)) {

		inode_incr_space(inode, number, reserve);
@@ -1611,6 +1620,7 @@ int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags) 
	for (cnt = 0; cnt < MAXQUOTAS; cnt++)

		warn[cnt].w_type = QUOTA_NL_NOWARN;



	dquots = i_dquot(inode);

	index = srcu_read_lock(&dquot_srcu);

	spin_lock(&dq_data_lock);

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
@@ -1652,13 +1662,14 @@ int dquot_alloc_inode(struct inode *inode) 
{

	int cnt, ret = 0, index;

	struct dquot_warn warn[MAXQUOTAS];

	struct dquot * const *dquots = i_dquot(inode);

	struct dquot * const *dquots;



	if (!dquot_active(inode))

		return 0;

	for (cnt = 0; cnt < MAXQUOTAS; cnt++)

		warn[cnt].w_type = QUOTA_NL_NOWARN;



	dquots = i_dquot(inode);

	index = srcu_read_lock(&dquot_srcu);

	spin_lock(&dq_data_lock);

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
@@ -1690,6 +1701,7 @@ EXPORT_SYMBOL(dquot_alloc_inode); 
 */

int dquot_claim_space_nodirty(struct inode *inode, qsize_t number)

{

	struct dquot **dquots;

	int cnt, index;



	if (!dquot_active(inode)) {
@@ -1697,18 +1709,18 @@ int dquot_claim_space_nodirty(struct inode *inode, qsize_t number) 
		return 0;

	}



	dquots = i_dquot(inode);

	index = srcu_read_lock(&dquot_srcu);

	spin_lock(&dq_data_lock);

	/* Claim reserved quotas to allocated quotas */

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		if (i_dquot(inode)[cnt])

			dquot_claim_reserved_space(i_dquot(inode)[cnt],

							number);

		if (dquots[cnt])

			dquot_claim_reserved_space(dquots[cnt], number);

	}

	/* Update inode bytes */

	inode_claim_rsv_space(inode, number);

	spin_unlock(&dq_data_lock);

	mark_all_dquot_dirty(i_dquot(inode));

	mark_all_dquot_dirty(dquots);

	srcu_read_unlock(&dquot_srcu, index);

	return 0;

}
@@ -1719,6 +1731,7 @@ EXPORT_SYMBOL(dquot_claim_space_nodirty); 
 */

void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number)

{

	struct dquot **dquots;

	int cnt, index;



	if (!dquot_active(inode)) {
@@ -1726,18 +1739,18 @@ void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number) 
		return;

	}



	dquots = i_dquot(inode);

	index = srcu_read_lock(&dquot_srcu);

	spin_lock(&dq_data_lock);

	/* Claim reserved quotas to allocated quotas */

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

		if (i_dquot(inode)[cnt])

			dquot_reclaim_reserved_space(i_dquot(inode)[cnt],

						     number);

		if (dquots[cnt])

			dquot_reclaim_reserved_space(dquots[cnt], number);

	}

	/* Update inode bytes */

	inode_reclaim_rsv_space(inode, number);

	spin_unlock(&dq_data_lock);

	mark_all_dquot_dirty(i_dquot(inode));

	mark_all_dquot_dirty(dquots);

	srcu_read_unlock(&dquot_srcu, index);

	return;

}
@@ -1750,7 +1763,7 @@ void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 
{

	unsigned int cnt;

	struct dquot_warn warn[MAXQUOTAS];

	struct dquot **dquots = i_dquot(inode);

	struct dquot **dquots;

	int reserve = flags & DQUOT_SPACE_RESERVE, index;



	if (!dquot_active(inode)) {
@@ -1758,6 +1771,7 @@ void __dquot_free_space(struct inode *inode, qsize_t number, int flags) 
		return;

	}



	dquots = i_dquot(inode);

	index = srcu_read_lock(&dquot_srcu);

	spin_lock(&dq_data_lock);

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
@@ -1793,12 +1807,13 @@ void dquot_free_inode(struct inode *inode) 
{

	unsigned int cnt;

	struct dquot_warn warn[MAXQUOTAS];

	struct dquot * const *dquots = i_dquot(inode);

	struct dquot * const *dquots;

	int index;



	if (!dquot_active(inode))

		return;



	dquots = i_dquot(inode);

	index = srcu_read_lock(&dquot_srcu);

	spin_lock(&dq_data_lock);

	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

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