From bc8230ee8e2ba967af780cdaf2dcc0f8e5eb45ca Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Thu, 8 Jun 2017 14:39:48 +0200 Subject: quota: Convert dqio_mutex to rwsem Convert dqio_mutex to rwsem and call it dqio_sem. No functional changes yet. Signed-off-by: Jan Kara --- include/linux/quota.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/quota.h b/include/linux/quota.h index bfd077ca6ac3..3a6df7461642 100644 --- a/include/linux/quota.h +++ b/include/linux/quota.h @@ -521,7 +521,7 @@ static inline void quota_send_warning(struct kqid qid, dev_t dev, struct quota_info { unsigned int flags; /* Flags for diskquotas on this device */ - struct mutex dqio_mutex; /* lock device while I/O in progress */ + struct rw_semaphore dqio_sem; /* Lock quota file while I/O in progress */ struct inode *files[MAXQUOTAS]; /* inodes of quotafiles */ struct mem_dqinfo info[MAXQUOTAS]; /* Information for each quota type */ const struct quota_format_ops *ops[MAXQUOTAS]; /* Operations for each type */ -- cgit v1.2.3 From 503330f3820fab13aa2a7b1f9e7633686acc7c79 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 2 Aug 2017 17:18:50 +0200 Subject: quota: Remove dq_wait_unused from dquot Currently every dquot carries a wait_queue_head_t used only when we are turning quotas off to wait for last users to drop dquot references. Since such rare case is not performance sensitive in any means, just use a global waitqueue for this and save space in struct dquot. Also convert the logic to use wait_event() instead of open-coding it. Signed-off-by: Jan Kara --- include/linux/quota.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/quota.h b/include/linux/quota.h index 3a6df7461642..ad6809f099ac 100644 --- a/include/linux/quota.h +++ b/include/linux/quota.h @@ -299,7 +299,6 @@ struct dquot { struct list_head dq_dirty; /* List of dirty dquots */ struct mutex dq_lock; /* dquot IO lock */ atomic_t dq_count; /* Use count */ - wait_queue_head_t dq_wait_unused; /* Wait queue for dquot to become unused */ struct super_block *dq_sb; /* superblock this applies to */ struct kqid dq_id; /* ID this applies to (uid, gid, projid) */ loff_t dq_off; /* Offset of dquot on disk */ -- cgit v1.2.3 From 834057bf846691552a8906f7ed3f67546e5f897c Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Thu, 3 Aug 2017 11:18:23 +0200 Subject: quota: Allow disabling tracking of dirty dquots in a list Filesystems that are journalling quotas generally don't need tracking of dirty dquots in a list since forcing a transaction commit flushes all quotas anyway. Allow filesystem to say it doesn't want dquots to be tracked as it reduces contention on the dq_list_lock. Signed-off-by: Jan Kara --- include/linux/quota.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/quota.h b/include/linux/quota.h index ad6809f099ac..eccc1cb6274e 100644 --- a/include/linux/quota.h +++ b/include/linux/quota.h @@ -490,6 +490,9 @@ enum { */ #define DQUOT_NEGATIVE_USAGE (1 << (DQUOT_STATE_LAST + 1)) /* Allow negative quota usage */ +/* Do not track dirty dquots in a list */ +#define DQUOT_NOLIST_DIRTY (1 << (DQUOT_STATE_LAST + 2)) + static inline unsigned int dquot_state_flag(unsigned int flags, int type) { return flags << type; -- cgit v1.2.3 From 0ed60de34a975804a256fb3fe233b1466c603be6 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 7 Aug 2017 17:07:28 +0200 Subject: quota: Inline functions into their callsites inode_add_rsv_space() and inode_sub_rsv_space() had only one callsite. Inline them there directly. inode_claim_rsv_space() and inode_reclaim_rsv_space() had two callsites so inline them there as well. This will simplify further locking changes. Signed-off-by: Jan Kara --- include/linux/quotaops.h | 5 ----- 1 file changed, 5 deletions(-) (limited to 'include/linux') diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h index dda22f45fc1b..0ce6fc49962e 100644 --- a/include/linux/quotaops.h +++ b/include/linux/quotaops.h @@ -38,11 +38,6 @@ void __quota_error(struct super_block *sb, const char *func, /* * declaration of quota_function calls in kernel. */ -void inode_add_rsv_space(struct inode *inode, qsize_t number); -void inode_claim_rsv_space(struct inode *inode, qsize_t number); -void inode_sub_rsv_space(struct inode *inode, qsize_t number); -void inode_reclaim_rsv_space(struct inode *inode, qsize_t number); - int dquot_initialize(struct inode *inode); bool dquot_initialize_needed(struct inode *inode); void dquot_drop(struct inode *inode); -- cgit v1.2.3 From f4a8116a4c8c8f754d0ec1498a2ba4b63d114e6a Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 8 Aug 2017 09:54:36 +0200 Subject: fs: Provide __inode_get_bytes() Provide helper __inode_get_bytes() which assumes i_lock is already acquired. Quota code will need this to be able to use i_lock to protect consistency of quota accounting information and inode usage. Signed-off-by: Jan Kara --- include/linux/fs.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/fs.h b/include/linux/fs.h index 6e1fd5d21248..d6e9ab7f184f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2998,6 +2998,10 @@ void __inode_add_bytes(struct inode *inode, loff_t bytes); void inode_add_bytes(struct inode *inode, loff_t bytes); void __inode_sub_bytes(struct inode *inode, loff_t bytes); void inode_sub_bytes(struct inode *inode, loff_t bytes); +static inline loff_t __inode_get_bytes(struct inode *inode) +{ + return (((loff_t)inode->i_blocks) << 9) + inode->i_bytes; +} loff_t inode_get_bytes(struct inode *inode); void inode_set_bytes(struct inode *inode, loff_t bytes); const char *simple_get_link(struct dentry *, struct inode *, -- cgit v1.2.3 From 7b9ca4c61bc278b771fb57d6290a31ab1fc7fdac Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 7 Aug 2017 13:19:50 +0200 Subject: quota: Reduce contention on dq_data_lock dq_data_lock is currently used to protect all modifications of quota accounting information, consistency of quota accounting on the inode, and dquot pointers from inode. As a result contention on the lock can be pretty heavy. Reduce the contention on the lock by protecting quota accounting information by a new dquot->dq_dqb_lock and consistency of quota accounting with inode usage by inode->i_lock. This change reduces time to create 500000 files on ext4 on ramdisk by 50 different processes in separate directories by 6% when user quota is turned on. When those 50 processes belong to 50 different users, the improvement is about 9%. Signed-off-by: Jan Kara --- include/linux/quota.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/quota.h b/include/linux/quota.h index eccc1cb6274e..074123975595 100644 --- a/include/linux/quota.h +++ b/include/linux/quota.h @@ -298,12 +298,13 @@ struct dquot { struct list_head dq_free; /* Free list element */ struct list_head dq_dirty; /* List of dirty dquots */ struct mutex dq_lock; /* dquot IO lock */ + spinlock_t dq_dqb_lock; /* Lock protecting dq_dqb changes */ atomic_t dq_count; /* Use count */ struct super_block *dq_sb; /* superblock this applies to */ struct kqid dq_id; /* ID this applies to (uid, gid, projid) */ loff_t dq_off; /* Offset of dquot on disk */ unsigned long dq_flags; /* See DQ_* */ - struct mem_dqblk dq_dqb; /* Diskquota usage */ + struct mem_dqblk dq_dqb; /* Diskquota usage [dq_dqb_lock] */ }; /* Operations which must be implemented by each quota format */ -- cgit v1.2.3 From 6c83fd5142c68294acb0e857b7bac2ce8a5077f7 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 21 Aug 2017 14:06:46 +0200 Subject: quota: Add lock annotations to struct members Add annotation which lock protects which struct members to struct dquot and struct mem_dqinfo. Signed-off-by: Jan Kara --- include/linux/quota.h | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'include/linux') diff --git a/include/linux/quota.h b/include/linux/quota.h index 074123975595..5ac9de4fcd6f 100644 --- a/include/linux/quota.h +++ b/include/linux/quota.h @@ -223,12 +223,12 @@ struct mem_dqinfo { struct quota_format_type *dqi_format; int dqi_fmt_id; /* Id of the dqi_format - used when turning * quotas on after remount RW */ - struct list_head dqi_dirty_list; /* List of dirty dquots */ - unsigned long dqi_flags; - unsigned int dqi_bgrace; - unsigned int dqi_igrace; - qsize_t dqi_max_spc_limit; - qsize_t dqi_max_ino_limit; + struct list_head dqi_dirty_list; /* List of dirty dquots [dq_list_lock] */ + unsigned long dqi_flags; /* DFQ_ flags [dq_data_lock] */ + unsigned int dqi_bgrace; /* Space grace time [dq_data_lock] */ + unsigned int dqi_igrace; /* Inode grace time [dq_data_lock] */ + qsize_t dqi_max_spc_limit; /* Maximum space limit [static] */ + qsize_t dqi_max_ino_limit; /* Maximum inode limit [static] */ void *dqi_priv; }; @@ -293,16 +293,16 @@ static inline void dqstats_dec(unsigned int type) * clear them when it sees fit. */ struct dquot { - struct hlist_node dq_hash; /* Hash list in memory */ - struct list_head dq_inuse; /* List of all quotas */ - struct list_head dq_free; /* Free list element */ - struct list_head dq_dirty; /* List of dirty dquots */ + struct hlist_node dq_hash; /* Hash list in memory [dq_list_lock] */ + struct list_head dq_inuse; /* List of all quotas [dq_list_lock] */ + struct list_head dq_free; /* Free list element [dq_list_lock] */ + struct list_head dq_dirty; /* List of dirty dquots [dq_list_lock] */ struct mutex dq_lock; /* dquot IO lock */ spinlock_t dq_dqb_lock; /* Lock protecting dq_dqb changes */ atomic_t dq_count; /* Use count */ struct super_block *dq_sb; /* superblock this applies to */ struct kqid dq_id; /* ID this applies to (uid, gid, projid) */ - loff_t dq_off; /* Offset of dquot on disk */ + loff_t dq_off; /* Offset of dquot on disk [dq_lock, stable once set] */ unsigned long dq_flags; /* See DQ_* */ struct mem_dqblk dq_dqb; /* Diskquota usage [dq_dqb_lock] */ }; -- cgit v1.2.3