diff options
| -rw-r--r-- | fs/gfs2/glock.c | 83 | ||||
| -rw-r--r-- | fs/gfs2/glock.h | 2 | ||||
| -rw-r--r-- | fs/gfs2/glops.c | 4 | ||||
| -rw-r--r-- | fs/gfs2/incore.h | 5 | ||||
| -rw-r--r-- | include/linux/lockref.h | 6 | ||||
| -rw-r--r-- | lib/lockref.c | 1 |
6 files changed, 52 insertions, 49 deletions
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index c2f41b4..e66a800 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -31,6 +31,7 @@ #include <linux/bit_spinlock.h> #include <linux/percpu.h> #include <linux/list_sort.h> +#include <linux/lockref.h> #include "gfs2.h" #include "incore.h" @@ -129,10 +130,10 @@ void gfs2_glock_free(struct gfs2_glock *gl) * */ -void gfs2_glock_hold(struct gfs2_glock *gl) +static void gfs2_glock_hold(struct gfs2_glock *gl) { - GLOCK_BUG_ON(gl, atomic_read(&gl->gl_ref) == 0); - atomic_inc(&gl->gl_ref); + GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref)); + lockref_get(&gl->gl_lockref); } /** @@ -187,20 +188,6 @@ static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl) } /** - * gfs2_glock_put_nolock() - Decrement reference count on glock - * @gl: The glock to put - * - * This function should only be used if the caller has its own reference - * to the glock, in addition to the one it is dropping. - */ - -void gfs2_glock_put_nolock(struct gfs2_glock *gl) -{ - if (atomic_dec_and_test(&gl->gl_ref)) - GLOCK_BUG_ON(gl, 1); -} - -/** * gfs2_glock_put() - Decrement reference count on glock * @gl: The glock to put * @@ -211,17 +198,22 @@ void gfs2_glock_put(struct gfs2_glock *gl) struct gfs2_sbd *sdp = gl->gl_sbd; struct address_space *mapping = gfs2_glock2aspace(gl); - if (atomic_dec_and_lock(&gl->gl_ref, &lru_lock)) { - __gfs2_glock_remove_from_lru(gl); - spin_unlock(&lru_lock); - spin_lock_bucket(gl->gl_hash); - hlist_bl_del_rcu(&gl->gl_list); - spin_unlock_bucket(gl->gl_hash); - GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); - GLOCK_BUG_ON(gl, mapping && mapping->nrpages); - trace_gfs2_glock_put(gl); - sdp->sd_lockstruct.ls_ops->lm_put_lock(gl); - } + if (lockref_put_or_lock(&gl->gl_lockref)) + return; + + lockref_mark_dead(&gl->gl_lockref); + + spin_lock(&lru_lock); + __gfs2_glock_remove_from_lru(gl); + spin_unlock(&lru_lock); + spin_unlock(&gl->gl_lockref.lock); + spin_lock_bucket(gl->gl_hash); + hlist_bl_del_rcu(&gl->gl_list); + spin_unlock_bucket(gl->gl_hash); + GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); + GLOCK_BUG_ON(gl, mapping && mapping->nrpages); + trace_gfs2_glock_put(gl); + sdp->sd_lockstruct.ls_ops->lm_put_lock(gl); } /** @@ -244,7 +236,7 @@ static struct gfs2_glock *search_bucket(unsigned int hash, continue; if (gl->gl_sbd != sdp) continue; - if (atomic_inc_not_zero(&gl->gl_ref)) + if (lockref_get_not_dead(&gl->gl_lockref)) return gl; } @@ -396,10 +388,11 @@ static void state_change(struct gfs2_glock *gl, unsigned int new_state) held2 = (new_state != LM_ST_UNLOCKED); if (held1 != held2) { + GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref)); if (held2) - gfs2_glock_hold(gl); + gl->gl_lockref.count++; else - gfs2_glock_put_nolock(gl); + gl->gl_lockref.count--; } if (held1 && held2 && list_empty(&gl->gl_holders)) clear_bit(GLF_QUEUED, &gl->gl_flags); @@ -626,9 +619,9 @@ out: out_sched: clear_bit(GLF_LOCK, &gl->gl_flags); smp_mb__after_clear_bit(); - gfs2_glock_hold(gl); + gl->gl_lockref.count++; if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) - gfs2_glock_put_nolock(gl); + gl->gl_lockref.count--; return; out_unlock: @@ -754,7 +747,7 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, gl->gl_sbd = sdp; gl->gl_flags = 0; gl->gl_name = name; - atomic_set(&gl->gl_ref, 1); + gl->gl_lockref.count = 1; gl->gl_state = LM_ST_UNLOCKED; gl->gl_target = LM_ST_UNLOCKED; gl->gl_demote_state = LM_ST_EXCLUSIVE; @@ -1356,10 +1349,10 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret) } } - spin_unlock(&gl->gl_spin); + gl->gl_lockref.count++; set_bit(GLF_REPLY_PENDING, &gl->gl_flags); - smp_wmb(); - gfs2_glock_hold(gl); + spin_unlock(&gl->gl_spin); + if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) gfs2_glock_put(gl); } @@ -1404,15 +1397,19 @@ __acquires(&lru_lock) while(!list_empty(list)) { gl = list_entry(list->next, struct gfs2_glock, gl_lru); list_del_init(&gl->gl_lru); + if (!spin_trylock(&gl->gl_spin)) { + list_add(&gl->gl_lru, &lru_list); + atomic_inc(&lru_count); + continue; + } clear_bit(GLF_LRU, &gl->gl_flags); - gfs2_glock_hold(gl); spin_unlock(&lru_lock); - spin_lock(&gl->gl_spin); + gl->gl_lockref.count++; if (demote_ok(gl)) handle_callback(gl, LM_ST_UNLOCKED, 0, false); WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags)); if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) - gfs2_glock_put_nolock(gl); + gl->gl_lockref.count--; spin_unlock(&gl->gl_spin); spin_lock(&lru_lock); } @@ -1493,7 +1490,7 @@ static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp, rcu_read_lock(); hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) { - if ((gl->gl_sbd == sdp) && atomic_inc_not_zero(&gl->gl_ref)) + if ((gl->gl_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref)) examiner(gl); } rcu_read_unlock(); @@ -1746,7 +1743,7 @@ int gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) state2str(gl->gl_demote_state), dtime, atomic_read(&gl->gl_ail_count), atomic_read(&gl->gl_revokes), - atomic_read(&gl->gl_ref), gl->gl_hold_time); + (int)gl->gl_lockref.count, gl->gl_hold_time); list_for_each_entry(gh, &gl->gl_holders, gh_list) { error = dump_holder(seq, gh); @@ -1902,7 +1899,7 @@ static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi) gi->nhash = 0; } /* Skip entries for other sb and dead entries */ - } while (gi->sdp != gi->gl->gl_sbd || atomic_read(&gi->gl->gl_ref) == 0); + } while (gi->sdp != gi->gl->gl_sbd || __lockref_is_dead(&gl->gl_lockref)); return 0; } diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h index 69f66e3..6647d77 100644 --- a/fs/gfs2/glock.h +++ b/fs/gfs2/glock.h @@ -181,8 +181,6 @@ static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl) extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, const struct gfs2_glock_operations *glops, int create, struct gfs2_glock **glp); -extern void gfs2_glock_hold(struct gfs2_glock *gl); -extern void gfs2_glock_put_nolock(struct gfs2_glock *gl); extern void gfs2_glock_put(struct gfs2_glock *gl); extern void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags, struct gfs2_holder *gh); diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c index e2e0a90..db908f6 100644 --- a/fs/gfs2/glops.c +++ b/fs/gfs2/glops.c @@ -525,9 +525,9 @@ static void iopen_go_callback(struct gfs2_glock *gl, bool remote) if (gl->gl_demote_state == LM_ST_UNLOCKED && gl->gl_state == LM_ST_SHARED && ip) { - gfs2_glock_hold(gl); + gl->gl_lockref.count++; if (queue_work(gfs2_delete_workqueue, &gl->gl_delete) == 0) - gfs2_glock_put_nolock(gl); + gl->gl_lockref.count--; } } diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h index 2ab4f8d..bb88e41 100644 --- a/fs/gfs2/incore.h +++ b/fs/gfs2/incore.h @@ -21,6 +21,7 @@ #include <linux/rbtree.h> #include <linux/ktime.h> #include <linux/percpu.h> +#include <linux/lockref.h> #define DIO_WAIT 0x00000010 #define DIO_METADATA 0x00000020 @@ -321,9 +322,9 @@ struct gfs2_glock { struct gfs2_sbd *gl_sbd; unsigned long gl_flags; /* GLF_... */ struct lm_lockname gl_name; - atomic_t gl_ref; - spinlock_t gl_spin; + struct lockref gl_lockref; +#define gl_spin gl_lockref.lock /* State fields protected by gl_spin */ unsigned int gl_state:2, /* Current state */ diff --git a/include/linux/lockref.h b/include/linux/lockref.h index f279ed9..13dfd36 100644 --- a/include/linux/lockref.h +++ b/include/linux/lockref.h @@ -36,4 +36,10 @@ extern int lockref_put_or_lock(struct lockref *); extern void lockref_mark_dead(struct lockref *); extern int lockref_get_not_dead(struct lockref *); +/* Must be called under spinlock for reliable results */ +static inline int __lockref_is_dead(const struct lockref *l) +{ + return ((int)l->count < 0); +} + #endif /* __LINUX_LOCKREF_H */ diff --git a/lib/lockref.c b/lib/lockref.c index e2cd2c0..8ff162f 100644 --- a/lib/lockref.c +++ b/lib/lockref.c @@ -136,6 +136,7 @@ void lockref_mark_dead(struct lockref *lockref) assert_spin_locked(&lockref->lock); lockref->count = -128; } +EXPORT_SYMBOL(lockref_mark_dead); /** * lockref_get_not_dead - Increments count unless the ref is dead |
