[PATCH 04/18] GFS2: Remove "double" locking in quota
From: swhiteho
Date: Wed Mar 18 2009 - 09:28:04 EST
From: Steven Whitehouse <swhiteho@xxxxxxxxxx>
We only really need a single spin lock for the quota data, so
lets just use the lru lock for now.
Signed-off-by: Steven Whitehouse <swhiteho@xxxxxxxxxx>
Cc: Abhijith Das <adas@xxxxxxxxxx>
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 592aa50..a0117d6 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -540,7 +540,6 @@ struct gfs2_sbd {
struct list_head sd_quota_list;
atomic_t sd_quota_count;
- spinlock_t sd_quota_spin;
struct mutex sd_quota_mutex;
wait_queue_head_t sd_quota_wait;
struct list_head sd_trunc_list;
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 530d3f6..402b6a2 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -98,7 +98,6 @@ static struct gfs2_sbd *init_sbd(struct super_block *sb)
mutex_init(&sdp->sd_jindex_mutex);
INIT_LIST_HEAD(&sdp->sd_quota_list);
- spin_lock_init(&sdp->sd_quota_spin);
mutex_init(&sdp->sd_quota_mutex);
init_waitqueue_head(&sdp->sd_quota_wait);
INIT_LIST_HEAD(&sdp->sd_trunc_list);
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 2ada6e1..e8ef0f8 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -104,13 +104,11 @@ int gfs2_shrink_qd_memory(int nr, gfp_t gfp_mask)
/* Free from the filesystem-specific list */
list_del(&qd->qd_list);
- spin_lock(&sdp->sd_quota_spin);
gfs2_assert_warn(sdp, !qd->qd_change);
gfs2_assert_warn(sdp, !qd->qd_slot_count);
gfs2_assert_warn(sdp, !qd->qd_bh_count);
gfs2_lvb_unhold(qd->qd_gl);
- spin_unlock(&sdp->sd_quota_spin);
atomic_dec(&sdp->sd_quota_count);
/* Delete it from the common reclaim list */
@@ -249,10 +247,10 @@ static int slot_get(struct gfs2_quota_data *qd)
unsigned int c, o = 0, b;
unsigned char byte = 0;
- spin_lock(&sdp->sd_quota_spin);
+ spin_lock(&qd_lru_lock);
if (qd->qd_slot_count++) {
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
return 0;
}
@@ -276,13 +274,13 @@ found:
sdp->sd_quota_bitmap[c][o] |= 1 << b;
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
return 0;
fail:
qd->qd_slot_count--;
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
return -ENOSPC;
}
@@ -290,23 +288,23 @@ static void slot_hold(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
- spin_lock(&sdp->sd_quota_spin);
+ spin_lock(&qd_lru_lock);
gfs2_assert(sdp, qd->qd_slot_count);
qd->qd_slot_count++;
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
}
static void slot_put(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
- spin_lock(&sdp->sd_quota_spin);
+ spin_lock(&qd_lru_lock);
gfs2_assert(sdp, qd->qd_slot_count);
if (!--qd->qd_slot_count) {
gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
qd->qd_slot = -1;
}
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
}
static int bh_get(struct gfs2_quota_data *qd)
@@ -382,7 +380,6 @@ static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
return 0;
spin_lock(&qd_lru_lock);
- spin_lock(&sdp->sd_quota_spin);
list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
@@ -406,7 +403,6 @@ static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
if (!found)
qd = NULL;
- spin_unlock(&sdp->sd_quota_spin);
spin_unlock(&qd_lru_lock);
if (qd) {
@@ -433,11 +429,9 @@ static int qd_trylock(struct gfs2_quota_data *qd)
return 0;
spin_lock(&qd_lru_lock);
- spin_lock(&sdp->sd_quota_spin);
if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
!test_bit(QDF_CHANGE, &qd->qd_flags)) {
- spin_unlock(&sdp->sd_quota_spin);
spin_unlock(&qd_lru_lock);
return 0;
}
@@ -451,7 +445,6 @@ static int qd_trylock(struct gfs2_quota_data *qd)
gfs2_assert_warn(sdp, qd->qd_slot_count);
qd->qd_slot_count++;
- spin_unlock(&sdp->sd_quota_spin);
spin_unlock(&qd_lru_lock);
gfs2_assert_warn(sdp, qd->qd_change_sync);
@@ -612,9 +605,9 @@ static void do_qc(struct gfs2_quota_data *qd, s64 change)
x = be64_to_cpu(qc->qc_change) + change;
qc->qc_change = cpu_to_be64(x);
- spin_lock(&sdp->sd_quota_spin);
+ spin_lock(&qd_lru_lock);
qd->qd_change = x;
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
if (!x) {
gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
@@ -945,9 +938,9 @@ static int need_sync(struct gfs2_quota_data *qd)
if (!qd->qd_qb.qb_limit)
return 0;
- spin_lock(&sdp->sd_quota_spin);
+ spin_lock(&qd_lru_lock);
value = qd->qd_change;
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
spin_lock(>->gt_spin);
num = gt->gt_quota_scale_num;
@@ -1040,9 +1033,9 @@ int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
continue;
value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
- spin_lock(&sdp->sd_quota_spin);
+ spin_lock(&qd_lru_lock);
value += qd->qd_change;
- spin_unlock(&sdp->sd_quota_spin);
+ spin_unlock(&qd_lru_lock);
if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
print_message(qd, "exceeded");
@@ -1228,9 +1221,7 @@ int gfs2_quota_init(struct gfs2_sbd *sdp)
qd->qd_slot_count = 1;
spin_lock(&qd_lru_lock);
- spin_lock(&sdp->sd_quota_spin);
gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
- spin_unlock(&sdp->sd_quota_spin);
list_add(&qd->qd_list, &sdp->sd_quota_list);
atomic_inc(&sdp->sd_quota_count);
spin_unlock(&qd_lru_lock);
@@ -1263,18 +1254,15 @@ void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
while (!list_empty(head)) {
qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
- spin_lock(&sdp->sd_quota_spin);
if (atomic_read(&qd->qd_count) > 1 ||
(atomic_read(&qd->qd_count) &&
!test_bit(QDF_CHANGE, &qd->qd_flags))) {
- spin_unlock(&sdp->sd_quota_spin);
list_move(&qd->qd_list, head);
spin_unlock(&qd_lru_lock);
schedule();
spin_lock(&qd_lru_lock);
continue;
}
- spin_unlock(&sdp->sd_quota_spin);
list_del(&qd->qd_list);
/* Also remove if this qd exists in the reclaim list */
--
1.6.0.3
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