dlm: use rwlock for lkbidr

Convert the lock for lkbidr to an rwlock.  Most idr lookups will use
the read lock.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index b675bffb61aef0bd3bcd36b359616f3aeb29348f..19e57cbd5b13470e811faf4f8e935aab7ad3e855 100644 (file)
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -582,7 +582,7 @@ struct dlm_ls {
        struct kobject          ls_kobj;
 
        struct idr              ls_lkbidr;
-       spinlock_t              ls_lkbidr_spin;
+       rwlock_t                ls_lkbidr_lock;
 
        struct rhashtable       ls_rsbtbl;
        rwlock_t                ls_rsbtbl_lock;

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 790d0fd76bbe78345dd771d6a089147756e44f29..bbbc9593a64e5603e07dba4372b355cff20c66bd 100644 (file)
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -1522,11 +1522,11 @@ static int _create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret,
        INIT_LIST_HEAD(&lkb->lkb_ownqueue);
        INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
 
-       spin_lock_bh(&ls->ls_lkbidr_spin);
+       write_lock_bh(&ls->ls_lkbidr_lock);
        rv = idr_alloc(&ls->ls_lkbidr, lkb, start, end, GFP_NOWAIT);
        if (rv >= 0)
                lkb->lkb_id = rv;
-       spin_unlock_bh(&ls->ls_lkbidr_spin);
+       write_unlock_bh(&ls->ls_lkbidr_lock);
 
        if (rv < 0) {
                log_error(ls, "create_lkb idr error %d", rv);
@@ -1547,11 +1547,11 @@ static int find_lkb(struct dlm_ls *ls, uint32_t lkid, struct dlm_lkb **lkb_ret)
 {
        struct dlm_lkb *lkb;
 
-       spin_lock_bh(&ls->ls_lkbidr_spin);
+       read_lock_bh(&ls->ls_lkbidr_lock);
        lkb = idr_find(&ls->ls_lkbidr, lkid);
        if (lkb)
                kref_get(&lkb->lkb_ref);
-       spin_unlock_bh(&ls->ls_lkbidr_spin);
+       read_unlock_bh(&ls->ls_lkbidr_lock);
 
        *lkb_ret = lkb;
        return lkb ? 0 : -ENOENT;
@@ -1567,36 +1567,6 @@ static void kill_lkb(struct kref *kref)
        DLM_ASSERT(!lkb->lkb_status, dlm_print_lkb(lkb););
 }
 
-/* TODO move this to lib/refcount.c */
-static __must_check bool
-dlm_refcount_dec_and_lock_bh(refcount_t *r, spinlock_t *lock)
-__cond_acquires(lock)
-{
-       if (refcount_dec_not_one(r))
-               return false;
-
-       spin_lock_bh(lock);
-       if (!refcount_dec_and_test(r)) {
-               spin_unlock_bh(lock);
-               return false;
-       }
-
-       return true;
-}
-
-/* TODO move this to include/linux/kref.h */
-static inline int dlm_kref_put_lock_bh(struct kref *kref,
-                                      void (*release)(struct kref *kref),
-                                      spinlock_t *lock)
-{
-       if (dlm_refcount_dec_and_lock_bh(&kref->refcount, lock)) {
-               release(kref);
-               return 1;
-       }
-
-       return 0;
-}
-
 /* __put_lkb() is used when an lkb may not have an rsb attached to
    it so we need to provide the lockspace explicitly */
 
@@ -1605,11 +1575,11 @@ static int __put_lkb(struct dlm_ls *ls, struct dlm_lkb *lkb)
        uint32_t lkid = lkb->lkb_id;
        int rv;
 
-       rv = dlm_kref_put_lock_bh(&lkb->lkb_ref, kill_lkb,
-                                 &ls->ls_lkbidr_spin);
+       rv = dlm_kref_put_write_lock_bh(&lkb->lkb_ref, kill_lkb,
+                                       &ls->ls_lkbidr_lock);
        if (rv) {
                idr_remove(&ls->ls_lkbidr, lkid);
-               spin_unlock_bh(&ls->ls_lkbidr_spin);
+               write_unlock_bh(&ls->ls_lkbidr_lock);
 
                detach_lkb(lkb);
 

diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index 04f4c74831ce2a86df6193948b7e193f79ed084a..5ce26882159e53b9d30b7283b1d58998c59a41a3 100644 (file)
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -431,7 +431,7 @@ static int new_lockspace(const char *name, const char *cluster,
                goto out_lsfree;
 
        idr_init(&ls->ls_lkbidr);
-       spin_lock_init(&ls->ls_lkbidr_spin);
+       rwlock_init(&ls->ls_lkbidr_lock);
 
        INIT_LIST_HEAD(&ls->ls_waiters);
        spin_lock_init(&ls->ls_waiters_lock);
@@ -676,7 +676,7 @@ static int lockspace_busy(struct dlm_ls *ls, int force)
 {
        int rv;
 
-       spin_lock_bh(&ls->ls_lkbidr_spin);
+       read_lock_bh(&ls->ls_lkbidr_lock);
        if (force == 0) {
                rv = idr_for_each(&ls->ls_lkbidr, lkb_idr_is_any, ls);
        } else if (force == 1) {
@@ -684,7 +684,7 @@ static int lockspace_busy(struct dlm_ls *ls, int force)
        } else {
                rv = 0;
        }
-       spin_unlock_bh(&ls->ls_lkbidr_spin);
+       read_unlock_bh(&ls->ls_lkbidr_lock);
        return rv;
 }