GFS2: Remove "double" locking in quota
authorSteven Whitehouse <swhiteho@redhat.com>
Thu, 8 Jan 2009 14:28:42 +0000 (14:28 +0000)
committerSteven Whitehouse <steve@dolmen.chygwyn.com>
Tue, 24 Mar 2009 11:21:13 +0000 (11:21 +0000)
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@redhat.com>
Cc: Abhijith Das <adas@redhat.com>
fs/gfs2/incore.h
fs/gfs2/ops_fstype.c
fs/gfs2/quota.c

index 592aa50..a0117d6 100644 (file)
@@ -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;
index 530d3f6..402b6a2 100644 (file)
@@ -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);
index 2ada6e1..e8ef0f8 100644 (file)
@@ -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->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 */