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Diffstat (limited to 'fs/gfs2/glock.c')
-rw-r--r--fs/gfs2/glock.c138
1 files changed, 91 insertions, 47 deletions
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 297421c..8b674b1 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -63,6 +63,7 @@ static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int
static DECLARE_RWSEM(gfs2_umount_flush_sem);
static struct dentry *gfs2_root;
static struct workqueue_struct *glock_workqueue;
+struct workqueue_struct *gfs2_delete_workqueue;
static LIST_HEAD(lru_list);
static atomic_t lru_count = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(lru_lock);
@@ -167,13 +168,33 @@ static void glock_free(struct gfs2_glock *gl)
*
*/
-static void gfs2_glock_hold(struct gfs2_glock *gl)
+void gfs2_glock_hold(struct gfs2_glock *gl)
{
GLOCK_BUG_ON(gl, atomic_read(&gl->gl_ref) == 0);
atomic_inc(&gl->gl_ref);
}
/**
+ * demote_ok - Check to see if it's ok to unlock a glock
+ * @gl: the glock
+ *
+ * Returns: 1 if it's ok
+ */
+
+static int demote_ok(const struct gfs2_glock *gl)
+{
+ const struct gfs2_glock_operations *glops = gl->gl_ops;
+
+ if (gl->gl_state == LM_ST_UNLOCKED)
+ return 0;
+ if (!list_empty(&gl->gl_holders))
+ return 0;
+ if (glops->go_demote_ok)
+ return glops->go_demote_ok(gl);
+ return 1;
+}
+
+/**
* gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list
* @gl: the glock
*
@@ -181,8 +202,13 @@ static void gfs2_glock_hold(struct gfs2_glock *gl)
static void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl)
{
+ int may_reclaim;
+ may_reclaim = (demote_ok(gl) &&
+ (atomic_read(&gl->gl_ref) == 1 ||
+ (gl->gl_name.ln_type == LM_TYPE_INODE &&
+ atomic_read(&gl->gl_ref) <= 2)));
spin_lock(&lru_lock);
- if (list_empty(&gl->gl_lru) && gl->gl_state != LM_ST_UNLOCKED) {
+ if (list_empty(&gl->gl_lru) && may_reclaim) {
list_add_tail(&gl->gl_lru, &lru_list);
atomic_inc(&lru_count);
}
@@ -190,6 +216,21 @@ static void gfs2_glock_schedule_for_reclaim(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_schedule_for_reclaim(gl);
+}
+
+/**
* gfs2_glock_put() - Decrement reference count on glock
* @gl: The glock to put
*
@@ -214,9 +255,9 @@ int gfs2_glock_put(struct gfs2_glock *gl)
rv = 1;
goto out;
}
- /* 1 for being hashed, 1 for having state != LM_ST_UNLOCKED */
- if (atomic_read(&gl->gl_ref) == 2)
- gfs2_glock_schedule_for_reclaim(gl);
+ spin_lock(&gl->gl_spin);
+ gfs2_glock_schedule_for_reclaim(gl);
+ spin_unlock(&gl->gl_spin);
write_unlock(gl_lock_addr(gl->gl_hash));
out:
return rv;
@@ -398,7 +439,7 @@ static void state_change(struct gfs2_glock *gl, unsigned int new_state)
if (held2)
gfs2_glock_hold(gl);
else
- gfs2_glock_put(gl);
+ gfs2_glock_put_nolock(gl);
}
gl->gl_state = new_state;
@@ -633,12 +674,35 @@ out:
out_sched:
gfs2_glock_hold(gl);
if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
- gfs2_glock_put(gl);
+ gfs2_glock_put_nolock(gl);
out_unlock:
clear_bit(GLF_LOCK, &gl->gl_flags);
goto out;
}
+static void delete_work_func(struct work_struct *work)
+{
+ struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete);
+ struct gfs2_sbd *sdp = gl->gl_sbd;
+ struct gfs2_inode *ip = NULL;
+ struct inode *inode;
+ u64 no_addr = 0;
+
+ spin_lock(&gl->gl_spin);
+ ip = (struct gfs2_inode *)gl->gl_object;
+ if (ip)
+ no_addr = ip->i_no_addr;
+ spin_unlock(&gl->gl_spin);
+ if (ip) {
+ inode = gfs2_ilookup(sdp->sd_vfs, no_addr);
+ if (inode) {
+ d_prune_aliases(inode);
+ iput(inode);
+ }
+ }
+ gfs2_glock_put(gl);
+}
+
static void glock_work_func(struct work_struct *work)
{
unsigned long delay = 0;
@@ -717,6 +781,7 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
gl->gl_sbd = sdp;
gl->gl_aspace = NULL;
INIT_DELAYED_WORK(&gl->gl_work, glock_work_func);
+ INIT_WORK(&gl->gl_delete, delete_work_func);
/* If this glock protects actual on-disk data or metadata blocks,
create a VFS inode to manage the pages/buffers holding them. */
@@ -858,6 +923,8 @@ static void handle_callback(struct gfs2_glock *gl, unsigned int state,
gl->gl_demote_state != state) {
gl->gl_demote_state = LM_ST_UNLOCKED;
}
+ if (gl->gl_ops->go_callback)
+ gl->gl_ops->go_callback(gl);
trace_gfs2_demote_rq(gl);
}
@@ -1274,33 +1341,12 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
gfs2_glock_put(gl);
}
-/**
- * demote_ok - Check to see if it's ok to unlock a glock
- * @gl: the glock
- *
- * Returns: 1 if it's ok
- */
-
-static int demote_ok(const struct gfs2_glock *gl)
-{
- const struct gfs2_glock_operations *glops = gl->gl_ops;
-
- if (gl->gl_state == LM_ST_UNLOCKED)
- return 0;
- if (!list_empty(&gl->gl_holders))
- return 0;
- if (glops->go_demote_ok)
- return glops->go_demote_ok(gl);
- return 1;
-}
-
static int gfs2_shrink_glock_memory(int nr, gfp_t gfp_mask)
{
struct gfs2_glock *gl;
int may_demote;
int nr_skipped = 0;
- int got_ref = 0;
LIST_HEAD(skipped);
if (nr == 0)
@@ -1315,37 +1361,29 @@ static int gfs2_shrink_glock_memory(int nr, gfp_t gfp_mask)
list_del_init(&gl->gl_lru);
atomic_dec(&lru_count);
+ /* Check if glock is about to be freed */
+ if (atomic_read(&gl->gl_ref) == 0)
+ continue;
+
/* Test for being demotable */
if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
gfs2_glock_hold(gl);
- got_ref = 1;
spin_unlock(&lru_lock);
spin_lock(&gl->gl_spin);
may_demote = demote_ok(gl);
- spin_unlock(&gl->gl_spin);
- clear_bit(GLF_LOCK, &gl->gl_flags);
if (may_demote) {
handle_callback(gl, LM_ST_UNLOCKED, 0);
nr--;
- if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
- gfs2_glock_put(gl);
- got_ref = 0;
}
+ if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+ gfs2_glock_put_nolock(gl);
+ spin_unlock(&gl->gl_spin);
+ clear_bit(GLF_LOCK, &gl->gl_flags);
spin_lock(&lru_lock);
- if (may_demote)
- continue;
- }
- if (list_empty(&gl->gl_lru) &&
- (atomic_read(&gl->gl_ref) <= (2 + got_ref))) {
- nr_skipped++;
- list_add(&gl->gl_lru, &skipped);
- }
- if (got_ref) {
- spin_unlock(&lru_lock);
- gfs2_glock_put(gl);
- spin_lock(&lru_lock);
- got_ref = 0;
+ continue;
}
+ nr_skipped++;
+ list_add(&gl->gl_lru, &skipped);
}
list_splice(&skipped, &lru_list);
atomic_add(nr_skipped, &lru_count);
@@ -1727,6 +1765,11 @@ int __init gfs2_glock_init(void)
glock_workqueue = create_workqueue("glock_workqueue");
if (IS_ERR(glock_workqueue))
return PTR_ERR(glock_workqueue);
+ gfs2_delete_workqueue = create_workqueue("delete_workqueue");
+ if (IS_ERR(gfs2_delete_workqueue)) {
+ destroy_workqueue(glock_workqueue);
+ return PTR_ERR(gfs2_delete_workqueue);
+ }
register_shrinker(&glock_shrinker);
@@ -1737,6 +1780,7 @@ void gfs2_glock_exit(void)
{
unregister_shrinker(&glock_shrinker);
destroy_workqueue(glock_workqueue);
+ destroy_workqueue(gfs2_delete_workqueue);
}
static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi)
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