--- /dev/null
+From: David Teigland <teigland@redhat.com>
+commit c7be761a8163d2f1ac0b606c21e4316b7abc5af7
+Author: David Teigland <teigland@redhat.com>
+Date: Wed Jan 7 16:50:41 2009 -0600
+Subject: dlm: change rsbtbl rwlock to spinlock
+
+ The rwlock is almost always used in write mode, so there's no reason
+ to not use a spinlock instead.
+
+Signed-off-by: David Teigland <teigland@redhat.com>
+Signed-off-by: Coly Li <coly.li@suse.de>
+
+diff --git a/fs/dlm/debug_fs.c b/fs/dlm/debug_fs.c
+index bc4af3e..1d1d274 100644
+--- a/fs/dlm/debug_fs.c
++++ b/fs/dlm/debug_fs.c
+@@ -416,7 +416,7 @@ static void *table_seq_start(struct seq_file *seq, loff_t *pos)
+ if (seq->op == &format3_seq_ops)
+ ri->format = 3;
+
+- read_lock(&ls->ls_rsbtbl[bucket].lock);
++ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ if (!list_empty(&ls->ls_rsbtbl[bucket].list)) {
+ list_for_each_entry(r, &ls->ls_rsbtbl[bucket].list,
+ res_hashchain) {
+@@ -424,12 +424,12 @@ static void *table_seq_start(struct seq_file *seq, loff_t *pos)
+ dlm_hold_rsb(r);
+ ri->rsb = r;
+ ri->bucket = bucket;
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ return ri;
+ }
+ }
+ }
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+
+ /*
+ * move to the first rsb in the next non-empty bucket
+@@ -447,18 +447,18 @@ static void *table_seq_start(struct seq_file *seq, loff_t *pos)
+ return NULL;
+ }
+
+- read_lock(&ls->ls_rsbtbl[bucket].lock);
++ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ if (!list_empty(&ls->ls_rsbtbl[bucket].list)) {
+ r = list_first_entry(&ls->ls_rsbtbl[bucket].list,
+ struct dlm_rsb, res_hashchain);
+ dlm_hold_rsb(r);
+ ri->rsb = r;
+ ri->bucket = bucket;
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ *pos = n;
+ return ri;
+ }
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ }
+ }
+
+@@ -477,7 +477,7 @@ static void *table_seq_next(struct seq_file *seq, void *iter_ptr, loff_t *pos)
+ * move to the next rsb in the same bucket
+ */
+
+- read_lock(&ls->ls_rsbtbl[bucket].lock);
++ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ rp = ri->rsb;
+ next = rp->res_hashchain.next;
+
+@@ -485,12 +485,12 @@ static void *table_seq_next(struct seq_file *seq, void *iter_ptr, loff_t *pos)
+ r = list_entry(next, struct dlm_rsb, res_hashchain);
+ dlm_hold_rsb(r);
+ ri->rsb = r;
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ dlm_put_rsb(rp);
+ ++*pos;
+ return ri;
+ }
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ dlm_put_rsb(rp);
+
+ /*
+@@ -509,18 +509,18 @@ static void *table_seq_next(struct seq_file *seq, void *iter_ptr, loff_t *pos)
+ return NULL;
+ }
+
+- read_lock(&ls->ls_rsbtbl[bucket].lock);
++ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ if (!list_empty(&ls->ls_rsbtbl[bucket].list)) {
+ r = list_first_entry(&ls->ls_rsbtbl[bucket].list,
+ struct dlm_rsb, res_hashchain);
+ dlm_hold_rsb(r);
+ ri->rsb = r;
+ ri->bucket = bucket;
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ *pos = n;
+ return ri;
+ }
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ }
+ }
+
+diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
+index ef2f1e3..076e86f 100644
+--- a/fs/dlm/dlm_internal.h
++++ b/fs/dlm/dlm_internal.h
+@@ -105,7 +105,7 @@ struct dlm_dirtable {
+ struct dlm_rsbtable {
+ struct list_head list;
+ struct list_head toss;
+- rwlock_t lock;
++ spinlock_t lock;
+ };
+
+ struct dlm_lkbtable {
+diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
+index 6cfe65b..01e7d39 100644
+--- a/fs/dlm/lock.c
++++ b/fs/dlm/lock.c
+@@ -412,9 +412,9 @@ static int search_rsb(struct dlm_ls *ls, char *name, int len, int b,
+ unsigned int flags, struct dlm_rsb **r_ret)
+ {
+ int error;
+- write_lock(&ls->ls_rsbtbl[b].lock);
++ spin_lock(&ls->ls_rsbtbl[b].lock);
+ error = _search_rsb(ls, name, len, b, flags, r_ret);
+- write_unlock(&ls->ls_rsbtbl[b].lock);
++ spin_unlock(&ls->ls_rsbtbl[b].lock);
+ return error;
+ }
+
+@@ -478,16 +478,16 @@ static int find_rsb(struct dlm_ls *ls, char *name, int namelen,
+ r->res_nodeid = nodeid;
+ }
+
+- write_lock(&ls->ls_rsbtbl[bucket].lock);
++ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ error = _search_rsb(ls, name, namelen, bucket, 0, &tmp);
+ if (!error) {
+- write_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ dlm_free_rsb(r);
+ r = tmp;
+ goto out;
+ }
+ list_add(&r->res_hashchain, &ls->ls_rsbtbl[bucket].list);
+- write_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ error = 0;
+ out:
+ *r_ret = r;
+@@ -530,9 +530,9 @@ static void put_rsb(struct dlm_rsb *r)
+ struct dlm_ls *ls = r->res_ls;
+ uint32_t bucket = r->res_bucket;
+
+- write_lock(&ls->ls_rsbtbl[bucket].lock);
++ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ kref_put(&r->res_ref, toss_rsb);
+- write_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ }
+
+ void dlm_put_rsb(struct dlm_rsb *r)
+@@ -967,7 +967,7 @@ static int shrink_bucket(struct dlm_ls *ls, int b)
+
+ for (;;) {
+ found = 0;
+- write_lock(&ls->ls_rsbtbl[b].lock);
++ spin_lock(&ls->ls_rsbtbl[b].lock);
+ list_for_each_entry_reverse(r, &ls->ls_rsbtbl[b].toss,
+ res_hashchain) {
+ if (!time_after_eq(jiffies, r->res_toss_time +
+@@ -978,20 +978,20 @@ static int shrink_bucket(struct dlm_ls *ls, int b)
+ }
+
+ if (!found) {
+- write_unlock(&ls->ls_rsbtbl[b].lock);
++ spin_unlock(&ls->ls_rsbtbl[b].lock);
+ break;
+ }
+
+ if (kref_put(&r->res_ref, kill_rsb)) {
+ list_del(&r->res_hashchain);
+- write_unlock(&ls->ls_rsbtbl[b].lock);
++ spin_unlock(&ls->ls_rsbtbl[b].lock);
+
+ if (is_master(r))
+ dir_remove(r);
+ dlm_free_rsb(r);
+ count++;
+ } else {
+- write_unlock(&ls->ls_rsbtbl[b].lock);
++ spin_unlock(&ls->ls_rsbtbl[b].lock);
+ log_error(ls, "tossed rsb in use %s", r->res_name);
+ }
+ }
+@@ -4224,7 +4224,7 @@ static struct dlm_rsb *find_purged_rsb(struct dlm_ls *ls, int bucket)
+ {
+ struct dlm_rsb *r, *r_ret = NULL;
+
+- read_lock(&ls->ls_rsbtbl[bucket].lock);
++ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ list_for_each_entry(r, &ls->ls_rsbtbl[bucket].list, res_hashchain) {
+ if (!rsb_flag(r, RSB_LOCKS_PURGED))
+ continue;
+@@ -4233,7 +4233,7 @@ static struct dlm_rsb *find_purged_rsb(struct dlm_ls *ls, int bucket)
+ r_ret = r;
+ break;
+ }
+- read_unlock(&ls->ls_rsbtbl[bucket].lock);
++ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+ return r_ret;
+ }
+
+diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
+index 8d86b79..aa32e5f 100644
+--- a/fs/dlm/lockspace.c
++++ b/fs/dlm/lockspace.c
+@@ -464,7 +464,7 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
+ for (i = 0; i < size; i++) {
+ INIT_LIST_HEAD(&ls->ls_rsbtbl[i].list);
+ INIT_LIST_HEAD(&ls->ls_rsbtbl[i].toss);
+- rwlock_init(&ls->ls_rsbtbl[i].lock);
++ spin_lock_init(&ls->ls_rsbtbl[i].lock);
+ }
+
+ size = dlm_config.ci_lkbtbl_size;
+diff --git a/fs/dlm/recover.c b/fs/dlm/recover.c
+index 80aba5b..eda43f3 100644
+--- a/fs/dlm/recover.c
++++ b/fs/dlm/recover.c
+@@ -726,7 +726,7 @@ int dlm_create_root_list(struct dlm_ls *ls)
+ }
+
+ for (i = 0; i < ls->ls_rsbtbl_size; i++) {
+- read_lock(&ls->ls_rsbtbl[i].lock);
++ spin_lock(&ls->ls_rsbtbl[i].lock);
+ list_for_each_entry(r, &ls->ls_rsbtbl[i].list, res_hashchain) {
+ list_add(&r->res_root_list, &ls->ls_root_list);
+ dlm_hold_rsb(r);
+@@ -737,7 +737,7 @@ int dlm_create_root_list(struct dlm_ls *ls)
+ but no other recovery steps should do anything with them. */
+
+ if (dlm_no_directory(ls)) {
+- read_unlock(&ls->ls_rsbtbl[i].lock);
++ spin_unlock(&ls->ls_rsbtbl[i].lock);
+ continue;
+ }
+
+@@ -745,7 +745,7 @@ int dlm_create_root_list(struct dlm_ls *ls)
+ list_add(&r->res_root_list, &ls->ls_root_list);
+ dlm_hold_rsb(r);
+ }
+- read_unlock(&ls->ls_rsbtbl[i].lock);
++ spin_unlock(&ls->ls_rsbtbl[i].lock);
+ }
+ out:
+ up_write(&ls->ls_root_sem);
+@@ -775,7 +775,7 @@ void dlm_clear_toss_list(struct dlm_ls *ls)
+ int i;
+
+ for (i = 0; i < ls->ls_rsbtbl_size; i++) {
+- write_lock(&ls->ls_rsbtbl[i].lock);
++ spin_lock(&ls->ls_rsbtbl[i].lock);
+ list_for_each_entry_safe(r, safe, &ls->ls_rsbtbl[i].toss,
+ res_hashchain) {
+ if (dlm_no_directory(ls) || !is_master(r)) {
+@@ -783,7 +783,7 @@ void dlm_clear_toss_list(struct dlm_ls *ls)
+ dlm_free_rsb(r);
+ }
+ }
+- write_unlock(&ls->ls_rsbtbl[i].lock);
++ spin_unlock(&ls->ls_rsbtbl[i].lock);
+ }
+ }
+
projects / ipfire-2.x.git / blobdiff