Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Implement wraparound-safe refcount_t and kref_t types based on
     generic atomic primitives (Peter Zijlstra)

   - Improve and fix the ww_mutex code (Nicolai Hähnle)

   - Add self-tests to the ww_mutex code (Chris Wilson)

   - Optimize percpu-rwsems with the 'rcuwait' mechanism (Davidlohr
     Bueso)

   - Micro-optimize the current-task logic all around the core kernel
     (Davidlohr Bueso)

   - Tidy up after recent optimizations: remove stale code and APIs,
     clean up the code (Waiman Long)

   - ... plus misc fixes, updates and cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
  fork: Fix task_struct alignment
  locking/spinlock/debug: Remove spinlock lockup detection code
  lockdep: Fix incorrect condition to print bug msgs for MAX_LOCKDEP_CHAIN_HLOCKS
  lkdtm: Convert to refcount_t testing
  kref: Implement 'struct kref' using refcount_t
  refcount_t: Introduce a special purpose refcount type
  sched/wake_q: Clarify queue reinit comment
  sched/wait, rcuwait: Fix typo in comment
  locking/mutex: Fix lockdep_assert_held() fail
  locking/rtmutex: Flip unlikely() branch to likely() in __rt_mutex_slowlock()
  locking/rwsem: Reinit wake_q after use
  locking/rwsem: Remove unnecessary atomic_long_t casts
  jump_labels: Move header guard #endif down where it belongs
  locking/atomic, kref: Implement kref_put_lock()
  locking/ww_mutex: Turn off __must_check for now
  locking/atomic, kref: Avoid more abuse
  locking/atomic, kref: Use kref_get_unless_zero() more
  locking/atomic, kref: Kill kref_sub()
  locking/atomic, kref: Add kref_read()
  locking/atomic, kref: Add KREF_INIT()
  ...

7 files changed, 31 insertions, 32 deletions

diff --git a/drivers/scsi/bnx2fc/bnx2fc_io.c b/drivers/scsi/bnx2fc/bnx2fc_io.c
index f501095f91ac..898461b146cc 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_io.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_io.c
@@ -74,7 +74,7 @@ static void bnx2fc_cmd_timeout(struct work_struct *work)
 				    &io_req->req_flags)) {
 			/* Handle internally generated ABTS timeout */
 			BNX2FC_IO_DBG(io_req, "ABTS timed out refcnt = %d\n",
-					io_req->refcount.refcount.counter);
+					kref_read(&io_req->refcount));
 			if (!(test_and_set_bit(BNX2FC_FLAG_ABTS_DONE,
 					       &io_req->req_flags))) {
 				/*
@@ -1141,7 +1141,7 @@ int bnx2fc_eh_abort(struct scsi_cmnd *sc_cmd)
 		return SUCCESS;
 	}
 	BNX2FC_IO_DBG(io_req, "eh_abort - refcnt = %d\n",
-		      io_req->refcount.refcount.counter);
+		      kref_read(&io_req->refcount));
 
 	/* Hold IO request across abort processing */
 	kref_get(&io_req->refcount);
@@ -1299,7 +1299,7 @@ void bnx2fc_process_cleanup_compl(struct bnx2fc_cmd *io_req,
 {
 	BNX2FC_IO_DBG(io_req, "Entered process_cleanup_compl "
 			      "refcnt = %d, cmd_type = %d\n",
-		   io_req->refcount.refcount.counter, io_req->cmd_type);
+		   kref_read(&io_req->refcount), io_req->cmd_type);
 	bnx2fc_scsi_done(io_req, DID_ERROR);
 	kref_put(&io_req->refcount, bnx2fc_cmd_release);
 	if (io_req->wait_for_comp)
@@ -1318,7 +1318,7 @@ void bnx2fc_process_abts_compl(struct bnx2fc_cmd *io_req,
 	BNX2FC_IO_DBG(io_req, "Entered process_abts_compl xid = 0x%x"
 			      "refcnt = %d, cmd_type = %d\n",
 		   io_req->xid,
-		   io_req->refcount.refcount.counter, io_req->cmd_type);
+		   kref_read(&io_req->refcount), io_req->cmd_type);
 
 	if (test_and_set_bit(BNX2FC_FLAG_ABTS_DONE,
 				       &io_req->req_flags)) {
diff --git a/drivers/scsi/cxgbi/libcxgbi.h b/drivers/scsi/cxgbi/libcxgbi.h
index 95ba99044c3e..18e0ea83d361 100644
--- a/drivers/scsi/cxgbi/libcxgbi.h
+++ b/drivers/scsi/cxgbi/libcxgbi.h
@@ -301,7 +301,7 @@ static inline void __cxgbi_sock_put(const char *fn, struct cxgbi_sock *csk)
 {
 	log_debug(1 << CXGBI_DBG_SOCK,
 		"%s, put csk 0x%p, ref %u-1.\n",
-		fn, csk, atomic_read(&csk->refcnt.refcount));
+		fn, csk, kref_read(&csk->refcnt));
 	kref_put(&csk->refcnt, cxgbi_sock_free);
 }
 #define cxgbi_sock_put(csk)	__cxgbi_sock_put(__func__, csk)
@@ -310,7 +310,7 @@ static inline void __cxgbi_sock_get(const char *fn, struct cxgbi_sock *csk)
 {
 	log_debug(1 << CXGBI_DBG_SOCK,
 		"%s, get csk 0x%p, ref %u+1.\n",
-		fn, csk, atomic_read(&csk->refcnt.refcount));
+		fn, csk, kref_read(&csk->refcnt));
 	kref_get(&csk->refcnt);
 }
 #define cxgbi_sock_get(csk)	__cxgbi_sock_get(__func__, csk)
diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
index a63542bac153..caa7a7b0ec53 100644
--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c
@@ -607,7 +607,7 @@ lpfc_debugfs_nodelist_data(struct lpfc_vport *vport, char *buf, int size)
 		len += snprintf(buf+len, size-len, "usgmap:%x ",
 			ndlp->nlp_usg_map);
 		len += snprintf(buf+len, size-len, "refcnt:%x",
-			atomic_read(&ndlp->kref.refcount));
+			kref_read(&ndlp->kref));
 		len +=  snprintf(buf+len, size-len, "\n");
 	}
 	spin_unlock_irq(shost->host_lock);
diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index 7b6bd8ed0d0b..63bef4566548 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -3690,7 +3690,7 @@ lpfc_mbx_cmpl_dflt_rpi(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 		lpfc_printf_vlog(ndlp->vport, KERN_INFO, LOG_NODE,
 				 "0006 rpi%x DID:%x flg:%x %d map:%x %p\n",
 				 ndlp->nlp_rpi, ndlp->nlp_DID, ndlp->nlp_flag,
-				 atomic_read(&ndlp->kref.refcount),
+				 kref_read(&ndlp->kref),
 				 ndlp->nlp_usg_map, ndlp);
 		if (NLP_CHK_NODE_ACT(ndlp)) {
 			lpfc_nlp_put(ndlp);
diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index ed223937798a..82047070cdc9 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -3440,7 +3440,7 @@ lpfc_mbx_cmpl_reg_login(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 	lpfc_printf_vlog(vport, KERN_INFO, LOG_SLI,
 			 "0002 rpi:%x DID:%x flg:%x %d map:%x %p\n",
 			 ndlp->nlp_rpi, ndlp->nlp_DID, ndlp->nlp_flag,
-			 atomic_read(&ndlp->kref.refcount),
+			 kref_read(&ndlp->kref),
 			 ndlp->nlp_usg_map, ndlp);
 	if (ndlp->nlp_flag & NLP_REG_LOGIN_SEND)
 		ndlp->nlp_flag &= ~NLP_REG_LOGIN_SEND;
@@ -3861,7 +3861,7 @@ out:
 	lpfc_printf_vlog(vport, KERN_INFO, LOG_SLI,
 			 "0003 rpi:%x DID:%x flg:%x %d map%x %p\n",
 			 ndlp->nlp_rpi, ndlp->nlp_DID, ndlp->nlp_flag,
-			 atomic_read(&ndlp->kref.refcount),
+			 kref_read(&ndlp->kref),
 			 ndlp->nlp_usg_map, ndlp);
 
 	if (vport->port_state < LPFC_VPORT_READY) {
@@ -4238,7 +4238,7 @@ lpfc_enable_node(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
 				"0277 lpfc_enable_node: ndlp:x%p "
 				"usgmap:x%x refcnt:%d\n",
 				(void *)ndlp, ndlp->nlp_usg_map,
-				atomic_read(&ndlp->kref.refcount));
+				kref_read(&ndlp->kref));
 		return NULL;
 	}
 	/* The ndlp should not already be in active mode */
@@ -4248,7 +4248,7 @@ lpfc_enable_node(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
 				"0278 lpfc_enable_node: ndlp:x%p "
 				"usgmap:x%x refcnt:%d\n",
 				(void *)ndlp, ndlp->nlp_usg_map,
-				atomic_read(&ndlp->kref.refcount));
+				kref_read(&ndlp->kref));
 		return NULL;
 	}
 
@@ -4272,7 +4272,7 @@ lpfc_enable_node(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
 				 "0008 rpi:%x DID:%x flg:%x refcnt:%d "
 				 "map:%x %p\n", ndlp->nlp_rpi, ndlp->nlp_DID,
 				 ndlp->nlp_flag,
-				 atomic_read(&ndlp->kref.refcount),
+				 kref_read(&ndlp->kref),
 				 ndlp->nlp_usg_map, ndlp);
 	}
 
@@ -4546,7 +4546,7 @@ lpfc_unreg_rpi(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
 				    (bf_get(lpfc_sli_intf_if_type,
 				     &phba->sli4_hba.sli_intf) ==
 				      LPFC_SLI_INTF_IF_TYPE_2) &&
-				    (atomic_read(&ndlp->kref.refcount) > 0)) {
+				    (kref_read(&ndlp->kref) > 0)) {
 					mbox->context1 = lpfc_nlp_get(ndlp);
 					mbox->mbox_cmpl =
 						lpfc_sli4_unreg_rpi_cmpl_clr;
@@ -4695,14 +4695,14 @@ lpfc_cleanup_node(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
 				"0280 lpfc_cleanup_node: ndlp:x%p "
 				"usgmap:x%x refcnt:%d\n",
 				(void *)ndlp, ndlp->nlp_usg_map,
-				atomic_read(&ndlp->kref.refcount));
+				kref_read(&ndlp->kref));
 		lpfc_dequeue_node(vport, ndlp);
 	} else {
 		lpfc_printf_vlog(vport, KERN_WARNING, LOG_NODE,
 				"0281 lpfc_cleanup_node: ndlp:x%p "
 				"usgmap:x%x refcnt:%d\n",
 				(void *)ndlp, ndlp->nlp_usg_map,
-				atomic_read(&ndlp->kref.refcount));
+				kref_read(&ndlp->kref));
 		lpfc_disable_node(vport, ndlp);
 	}
 
@@ -4791,7 +4791,7 @@ lpfc_nlp_remove(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp)
 		lpfc_printf_vlog(vport, KERN_INFO, LOG_NODE,
 				 "0005 rpi:%x DID:%x flg:%x %d map:%x %p\n",
 				 ndlp->nlp_rpi, ndlp->nlp_DID, ndlp->nlp_flag,
-				 atomic_read(&ndlp->kref.refcount),
+				 kref_read(&ndlp->kref),
 				 ndlp->nlp_usg_map, ndlp);
 		if ((mbox = mempool_alloc(phba->mbox_mem_pool, GFP_KERNEL))
 			!= NULL) {
@@ -5557,7 +5557,7 @@ lpfc_mbx_cmpl_fdmi_reg_login(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 	lpfc_printf_vlog(vport, KERN_INFO, LOG_SLI,
 			 "0004 rpi:%x DID:%x flg:%x %d map:%x %p\n",
 			 ndlp->nlp_rpi, ndlp->nlp_DID, ndlp->nlp_flag,
-			 atomic_read(&ndlp->kref.refcount),
+			 kref_read(&ndlp->kref),
 			 ndlp->nlp_usg_map, ndlp);
 	/*
 	 * Start issuing Fabric-Device Management Interface (FDMI) command to
@@ -5728,7 +5728,7 @@ lpfc_nlp_init(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
 				 "0007 rpi:%x DID:%x flg:%x refcnt:%d "
 				 "map:%x %p\n", ndlp->nlp_rpi, ndlp->nlp_DID,
 				 ndlp->nlp_flag,
-				 atomic_read(&ndlp->kref.refcount),
+				 kref_read(&ndlp->kref),
 				 ndlp->nlp_usg_map, ndlp);
 
 		ndlp->active_rrqs_xri_bitmap =
@@ -5767,7 +5767,7 @@ lpfc_nlp_release(struct kref *kref)
 			"0279 lpfc_nlp_release: ndlp:x%p did %x "
 			"usgmap:x%x refcnt:%d rpi:%x\n",
 			(void *)ndlp, ndlp->nlp_DID, ndlp->nlp_usg_map,
-			atomic_read(&ndlp->kref.refcount), ndlp->nlp_rpi);
+			kref_read(&ndlp->kref), ndlp->nlp_rpi);
 
 	/* remove ndlp from action. */
 	lpfc_nlp_remove(ndlp->vport, ndlp);
@@ -5804,7 +5804,7 @@ lpfc_nlp_get(struct lpfc_nodelist *ndlp)
 		lpfc_debugfs_disc_trc(ndlp->vport, LPFC_DISC_TRC_NODE,
 			"node get:        did:x%x flg:x%x refcnt:x%x",
 			ndlp->nlp_DID, ndlp->nlp_flag,
-			atomic_read(&ndlp->kref.refcount));
+			kref_read(&ndlp->kref));
 		/* The check of ndlp usage to prevent incrementing the
 		 * ndlp reference count that is in the process of being
 		 * released.
@@ -5817,7 +5817,7 @@ lpfc_nlp_get(struct lpfc_nodelist *ndlp)
 				"0276 lpfc_nlp_get: ndlp:x%p "
 				"usgmap:x%x refcnt:%d\n",
 				(void *)ndlp, ndlp->nlp_usg_map,
-				atomic_read(&ndlp->kref.refcount));
+				kref_read(&ndlp->kref));
 			return NULL;
 		} else
 			kref_get(&ndlp->kref);
@@ -5844,7 +5844,7 @@ lpfc_nlp_put(struct lpfc_nodelist *ndlp)
 	lpfc_debugfs_disc_trc(ndlp->vport, LPFC_DISC_TRC_NODE,
 	"node put:        did:x%x flg:x%x refcnt:x%x",
 		ndlp->nlp_DID, ndlp->nlp_flag,
-		atomic_read(&ndlp->kref.refcount));
+		kref_read(&ndlp->kref));
 	phba = ndlp->phba;
 	spin_lock_irqsave(&phba->ndlp_lock, flags);
 	/* Check the ndlp memory free acknowledge flag to avoid the
@@ -5857,7 +5857,7 @@ lpfc_nlp_put(struct lpfc_nodelist *ndlp)
 				"0274 lpfc_nlp_put: ndlp:x%p "
 				"usgmap:x%x refcnt:%d\n",
 				(void *)ndlp, ndlp->nlp_usg_map,
-				atomic_read(&ndlp->kref.refcount));
+				kref_read(&ndlp->kref));
 		return 1;
 	}
 	/* Check the ndlp inactivate log flag to avoid the possible
@@ -5870,7 +5870,7 @@ lpfc_nlp_put(struct lpfc_nodelist *ndlp)
 				"0275 lpfc_nlp_put: ndlp:x%p "
 				"usgmap:x%x refcnt:%d\n",
 				(void *)ndlp, ndlp->nlp_usg_map,
-				atomic_read(&ndlp->kref.refcount));
+				kref_read(&ndlp->kref));
 		return 1;
 	}
 	/* For last put, mark the ndlp usage flags to make sure no
@@ -5878,7 +5878,7 @@ lpfc_nlp_put(struct lpfc_nodelist *ndlp)
 	 * in between the process when the final kref_put has been
 	 * invoked on this ndlp.
 	 */
-	if (atomic_read(&ndlp->kref.refcount) == 1) {
+	if (kref_read(&ndlp->kref) == 1) {
 		/* Indicate ndlp is put to inactive state. */
 		NLP_SET_IACT_REQ(ndlp);
 		/* Acknowledge ndlp memory free has been seen. */
@@ -5906,8 +5906,8 @@ lpfc_nlp_not_used(struct lpfc_nodelist *ndlp)
 	lpfc_debugfs_disc_trc(ndlp->vport, LPFC_DISC_TRC_NODE,
 		"node not used:   did:x%x flg:x%x refcnt:x%x",
 		ndlp->nlp_DID, ndlp->nlp_flag,
-		atomic_read(&ndlp->kref.refcount));
-	if (atomic_read(&ndlp->kref.refcount) == 1)
+		kref_read(&ndlp->kref));
+	if (kref_read(&ndlp->kref) == 1)
 		if (lpfc_nlp_put(ndlp))
 			return 1;
 	return 0;
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 4776fd85514f..64717c171b15 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -2660,8 +2660,7 @@ lpfc_cleanup(struct lpfc_vport *vport)
 						"usgmap:x%x refcnt:%d\n",
 						ndlp->nlp_DID, (void *)ndlp,
 						ndlp->nlp_usg_map,
-						atomic_read(
-							&ndlp->kref.refcount));
+						kref_read(&ndlp->kref));
 			}
 			break;
 		}
diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
index d925910be761..3084983c1287 100644
--- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c
+++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
@@ -371,7 +371,7 @@ static int tcm_qla2xxx_write_pending(struct se_cmd *se_cmd)
 		 */
 		pr_debug("write_pending aborted cmd[%p] refcount %d "
 			"transport_state %x, t_state %x, se_cmd_flags %x\n",
-			cmd,cmd->se_cmd.cmd_kref.refcount.counter,
+			cmd, kref_read(&cmd->se_cmd.cmd_kref),
 			cmd->se_cmd.transport_state,
 			cmd->se_cmd.t_state,
 			cmd->se_cmd.se_cmd_flags);
@@ -584,7 +584,7 @@ static int tcm_qla2xxx_queue_data_in(struct se_cmd *se_cmd)
 		 */
 		pr_debug("queue_data_in aborted cmd[%p] refcount %d "
 			"transport_state %x, t_state %x, se_cmd_flags %x\n",
-			cmd,cmd->se_cmd.cmd_kref.refcount.counter,
+			cmd, kref_read(&cmd->se_cmd.cmd_kref),
 			cmd->se_cmd.transport_state,
 			cmd->se_cmd.t_state,
 			cmd->se_cmd.se_cmd_flags);