locking/atomic, kref: Add kref_read()

Since we need to change the implementation, stop exposing internals.

Provide kref_read() to read the current reference count; typically
used for debug messages.

Kills two anti-patterns:

	atomic_read(&kref->refcount)
	kref->refcount.counter

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

6 files changed, 14 insertions, 14 deletions

diff --git a/fs/ocfs2/cluster/netdebug.c b/fs/ocfs2/cluster/netdebug.c
index 27d1242c8383..564c504d6efd 100644
--- a/fs/ocfs2/cluster/netdebug.c
+++ b/fs/ocfs2/cluster/netdebug.c
@@ -349,7 +349,7 @@ static void sc_show_sock_container(struct seq_file *seq,
 		   "  func key:        0x%08x\n"
 		   "  func type:       %u\n",
 		   sc,
-		   atomic_read(&sc->sc_kref.refcount),
+		   kref_read(&sc->sc_kref),
 		   &saddr, inet ? ntohs(sport) : 0,
 		   &daddr, inet ? ntohs(dport) : 0,
 		   sc->sc_node->nd_name,
diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c
index d4b5c81f0445..ec000575e863 100644
--- a/fs/ocfs2/cluster/tcp.c
+++ b/fs/ocfs2/cluster/tcp.c
@@ -97,7 +97,7 @@
 	typeof(sc) __sc = (sc);						\
 	mlog(ML_SOCKET, "[sc %p refs %d sock %p node %u page %p "	\
 	     "pg_off %zu] " fmt, __sc,					\
-	     atomic_read(&__sc->sc_kref.refcount), __sc->sc_sock,	\
+	     kref_read(&__sc->sc_kref), __sc->sc_sock,	\
 	    __sc->sc_node->nd_num, __sc->sc_page, __sc->sc_page_off ,	\
 	    ##args);							\
 } while (0)
diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c
index e7b760deefae..9b984cae4c4e 100644
--- a/fs/ocfs2/dlm/dlmdebug.c
+++ b/fs/ocfs2/dlm/dlmdebug.c
@@ -81,7 +81,7 @@ static void __dlm_print_lock(struct dlm_lock *lock)
 	       lock->ml.type, lock->ml.convert_type, lock->ml.node,
 	       dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
 	       dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
-	       atomic_read(&lock->lock_refs.refcount),
+	       kref_read(&lock->lock_refs),
 	       (list_empty(&lock->ast_list) ? 'y' : 'n'),
 	       (lock->ast_pending ? 'y' : 'n'),
 	       (list_empty(&lock->bast_list) ? 'y' : 'n'),
@@ -106,7 +106,7 @@ void __dlm_print_one_lock_resource(struct dlm_lock_resource *res)
 	printk("lockres: %s, owner=%u, state=%u\n",
 	       buf, res->owner, res->state);
 	printk("  last used: %lu, refcnt: %u, on purge list: %s\n",
-	       res->last_used, atomic_read(&res->refs.refcount),
+	       res->last_used, kref_read(&res->refs),
 	       list_empty(&res->purge) ? "no" : "yes");
 	printk("  on dirty list: %s, on reco list: %s, "
 	       "migrating pending: %s\n",
@@ -298,7 +298,7 @@ static int dump_mle(struct dlm_master_list_entry *mle, char *buf, int len)
 			mle_type, mle->master, mle->new_master,
 			!list_empty(&mle->hb_events),
 			!!mle->inuse,
-			atomic_read(&mle->mle_refs.refcount));
+			kref_read(&mle->mle_refs));
 
 	out += snprintf(buf + out, len - out, "Maybe=");
 	out += stringify_nodemap(mle->maybe_map, O2NM_MAX_NODES,
@@ -494,7 +494,7 @@ static int dump_lock(struct dlm_lock *lock, int list_type, char *buf, int len)
 		       lock->ast_pending, lock->bast_pending,
 		       lock->convert_pending, lock->lock_pending,
 		       lock->cancel_pending, lock->unlock_pending,
-		       atomic_read(&lock->lock_refs.refcount));
+		       kref_read(&lock->lock_refs));
 	spin_unlock(&lock->spinlock);
 
 	return out;
@@ -521,7 +521,7 @@ static int dump_lockres(struct dlm_lock_resource *res, char *buf, int len)
 			!list_empty(&res->recovering),
 			res->inflight_locks, res->migration_pending,
 			atomic_read(&res->asts_reserved),
-			atomic_read(&res->refs.refcount));
+			kref_read(&res->refs));
 
 	/* refmap */
 	out += snprintf(buf + out, len - out, "RMAP:");
@@ -777,7 +777,7 @@ static int debug_state_print(struct dlm_ctxt *dlm, char *buf, int len)
 	/* Purge Count: xxx  Refs: xxx */
 	out += snprintf(buf + out, len - out,
 			"Purge Count: %d  Refs: %d\n", dlm->purge_count,
-			atomic_read(&dlm->dlm_refs.refcount));
+			kref_read(&dlm->dlm_refs));
 
 	/* Dead Node: xxx */
 	out += snprintf(buf + out, len - out,
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 733e4e79c8e2..32fd261ae13d 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -2072,7 +2072,7 @@ static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
 	INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
 
 	mlog(0, "context init: refcount %u\n",
-		  atomic_read(&dlm->dlm_refs.refcount));
+		  kref_read(&dlm->dlm_refs));
 
 leave:
 	if (ret < 0 && dlm) {
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index a464c8088170..7025d8c27999 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -233,7 +233,7 @@ static void __dlm_put_mle(struct dlm_master_list_entry *mle)
 
 	assert_spin_locked(&dlm->spinlock);
 	assert_spin_locked(&dlm->master_lock);
-	if (!atomic_read(&mle->mle_refs.refcount)) {
+	if (!kref_read(&mle->mle_refs)) {
 		/* this may or may not crash, but who cares.
 		 * it's a BUG. */
 		mlog(ML_ERROR, "bad mle: %p\n", mle);
@@ -1124,9 +1124,9 @@ recheck:
 		unsigned long timeo = msecs_to_jiffies(DLM_MASTERY_TIMEOUT_MS);
 
 		/*
-		if (atomic_read(&mle->mle_refs.refcount) < 2)
+		if (kref_read(&mle->mle_refs) < 2)
 			mlog(ML_ERROR, "mle (%p) refs=%d, name=%.*s\n", mle,
-			atomic_read(&mle->mle_refs.refcount),
+			kref_read(&mle->mle_refs),
 			res->lockname.len, res->lockname.name);
 		*/
 		atomic_set(&mle->woken, 0);
@@ -1979,7 +1979,7 @@ ok:
 		 * on this mle. */
 		spin_lock(&dlm->master_lock);
 
-		rr = atomic_read(&mle->mle_refs.refcount);
+		rr = kref_read(&mle->mle_refs);
 		if (mle->inuse > 0) {
 			if (extra_ref && rr < 3)
 				err = 1;
diff --git a/fs/ocfs2/dlm/dlmunlock.c b/fs/ocfs2/dlm/dlmunlock.c
index 1082b2c3014b..63d701cd1e2e 100644
--- a/fs/ocfs2/dlm/dlmunlock.c
+++ b/fs/ocfs2/dlm/dlmunlock.c
@@ -251,7 +251,7 @@ leave:
 		mlog(0, "lock %u:%llu should be gone now! refs=%d\n",
 		     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
 		     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
-		     atomic_read(&lock->lock_refs.refcount)-1);
+		     kref_read(&lock->lock_refs)-1);
 		dlm_lock_put(lock);
 	}
 	if (actions & DLM_UNLOCK_CALL_AST)