[SCSI] zfcp: Fix sparse warning by providing new entry in dbf

drivers/s390/scsi/zfcp_dbf.c:692:2: warning: context imbalance in 'zfcp_rec_dbf_event_thread' - different lock contexts for basic block Replace the parameter indicating if the lock is held with a new entry function that only acquires the lock. This makes the lock handling more visible and removes the sparse warning. Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] zfcp: Fix sparse warning by providing new entry in dbf
drivers/s390/scsi/zfcp_dbf.c:692:2: warning: context imbalance in 'zfcp_rec_dbf_event_thread' - different lock contexts for basic block Replace the parameter indicating if the lock is held with a new entry function that only acquires the lock. This makes the lock handling more visible and removes the sparse warning. Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Christof Schmitt · James Bottomley
1 parent 7337891f38
Showing 3 changed files with 28 additions and 17 deletions Side-by-side Diff
drivers/s390/scsi/zfcp_dbf.c
drivers/s390/scsi/zfcp_erp.c
drivers/s390/scsi/zfcp_ext.h
@@ -670,24 +670,20 @@
  * zfcp_rec_dbf_event_thread - trace event related to recovery thread operation
  * @id2: identifier for event
  * @adapter: adapter
- * @lock: non-zero value indicates that erp_lock has not yet been acquired
+ * This function assumes that the caller is holding erp_lock.
  */
-void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter, int lock)
+void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter)
 {
 	struct zfcp_rec_dbf_record *r = &adapter->rec_dbf_buf;
 	unsigned long flags = 0;
 	struct list_head *entry;
 	unsigned ready = 0, running = 0, total;
  
-	if (lock)
-		read_lock_irqsave(&adapter->erp_lock, flags);
 	list_for_each(entry, &adapter->erp_ready_head)
 		ready++;
 	list_for_each(entry, &adapter->erp_running_head)
 		running++;
 	total = adapter->erp_total_count;
-	if (lock)
-		read_unlock_irqrestore(&adapter->erp_lock, flags);
  
 	spin_lock_irqsave(&adapter->rec_dbf_lock, flags);
 	memset(r, 0, sizeof(*r));
@@ -698,6 +694,21 @@
 	r->u.thread.running = running;
 	debug_event(adapter->rec_dbf, 6, r, sizeof(*r));
 	spin_unlock_irqrestore(&adapter->rec_dbf_lock, flags);
+}
+
+/**
+ * zfcp_rec_dbf_event_thread - trace event related to recovery thread operation
+ * @id2: identifier for event
+ * @adapter: adapter
+ * This function assumes that the caller does not hold erp_lock.
+ */
+void zfcp_rec_dbf_event_thread_lock(u8 id2, struct zfcp_adapter *adapter)
+{
+	unsigned long flags;
+
+	read_lock_irqsave(&adapter->erp_lock, flags);
+	zfcp_rec_dbf_event_thread(id2, adapter);
+	read_unlock_irqrestore(&adapter->erp_lock, flags);
 }
  
 static void zfcp_rec_dbf_event_target(u8 id2, void *ref,
@@ -783,7 +783,7 @@
  
 	zfcp_erp_action_to_ready(erp_action);
 	up(&adapter->erp_ready_sem);
-	zfcp_rec_dbf_event_thread(2, adapter, 0);
+	zfcp_rec_dbf_event_thread(2, adapter);
 }
  
 /*
@@ -995,7 +995,7 @@
  
 	atomic_set_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_KILL, &adapter->status);
 	up(&adapter->erp_ready_sem);
-	zfcp_rec_dbf_event_thread(2, adapter, 1);
+	zfcp_rec_dbf_event_thread_lock(2, adapter);
  
 	wait_event(adapter->erp_thread_wqh,
 		   !atomic_test_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP,
  
@@ -1050,9 +1050,9 @@
 		 * no action in 'ready' queue to be processed and
 		 * thread is not to be killed
 		 */
-		zfcp_rec_dbf_event_thread(4, adapter, 1);
+		zfcp_rec_dbf_event_thread_lock(4, adapter);
 		down_interruptible(&adapter->erp_ready_sem);
-		zfcp_rec_dbf_event_thread(5, adapter, 1);
+		zfcp_rec_dbf_event_thread_lock(5, adapter);
 	}
  
 	atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP, &adapter->status);
  
@@ -2062,9 +2062,9 @@
 		 * _must_ be the one belonging to the 'exchange config
 		 * data' request.
 		 */
-		zfcp_rec_dbf_event_thread(6, adapter, 1);
+		zfcp_rec_dbf_event_thread_lock(6, adapter);
 		down(&adapter->erp_ready_sem);
-		zfcp_rec_dbf_event_thread(7, adapter, 1);
+		zfcp_rec_dbf_event_thread_lock(7, adapter);
 		if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) {
 			ZFCP_LOG_INFO("error: exchange of configuration data "
 				      "for adapter %s timed out\n",
  
@@ -2118,9 +2118,9 @@
 	}
  
 	ret = ZFCP_ERP_SUCCEEDED;
-	zfcp_rec_dbf_event_thread(8, adapter, 1);
+	zfcp_rec_dbf_event_thread_lock(8, adapter);
 	down(&adapter->erp_ready_sem);
-	zfcp_rec_dbf_event_thread(9, adapter, 1);
+	zfcp_rec_dbf_event_thread_lock(9, adapter);
 	if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) {
 		ZFCP_LOG_INFO("error: exchange port data timed out (adapter "
 			      "%s)\n", zfcp_get_busid_by_adapter(adapter));
@@ -2876,7 +2876,7 @@
 	/* finally put it into 'ready' queue and kick erp thread */
 	list_add_tail(&erp_action->list, &adapter->erp_ready_head);
 	up(&adapter->erp_ready_sem);
-	zfcp_rec_dbf_event_thread(1, adapter, 0);
+	zfcp_rec_dbf_event_thread(1, adapter);
 	retval = 0;
  out:
 	zfcp_rec_dbf_event_trigger(id, ref, want, need, erp_action,
@@ -169,8 +169,8 @@
 extern void zfcp_erp_unit_access_changed(struct zfcp_unit *, u8, void *);
  
 /******************************** AUX ****************************************/
-extern void zfcp_rec_dbf_event_thread(u8 id, struct zfcp_adapter *adapter,
-				      int lock);
+extern void zfcp_rec_dbf_event_thread(u8 id, struct zfcp_adapter *adapter);
+extern void zfcp_rec_dbf_event_thread_lock(u8 id, struct zfcp_adapter *adapter);
 extern void zfcp_rec_dbf_event_adapter(u8 id, void *ref, struct zfcp_adapter *);
 extern void zfcp_rec_dbf_event_port(u8 id, void *ref, struct zfcp_port *port);
 extern void zfcp_rec_dbf_event_unit(u8 id, void *ref, struct zfcp_unit *unit);
...	...	@@ -670,24 +670,20 @@
670	670	* zfcp_rec_dbf_event_thread - trace event related to recovery thread operation
671	671	* @id2: identifier for event
672	672	* @adapter: adapter
673		- * @lock: non-zero value indicates that erp_lock has not yet been acquired
	673	+ * This function assumes that the caller is holding erp_lock.
674	674	*/
675		-void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter, int lock)
	675	+void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter)
676	676	{
677	677	struct zfcp_rec_dbf_record *r = &adapter->rec_dbf_buf;
678	678	unsigned long flags = 0;
679	679	struct list_head *entry;
680	680	unsigned ready = 0, running = 0, total;
681	681
682		- if (lock)
683		- read_lock_irqsave(&adapter->erp_lock, flags);
684	682	list_for_each(entry, &adapter->erp_ready_head)
685	683	ready++;
686	684	list_for_each(entry, &adapter->erp_running_head)
687	685	running++;
688	686	total = adapter->erp_total_count;
689		- if (lock)
690		- read_unlock_irqrestore(&adapter->erp_lock, flags);
691	687
692	688	spin_lock_irqsave(&adapter->rec_dbf_lock, flags);
693	689	memset(r, 0, sizeof(*r));
...	...	@@ -698,6 +694,21 @@
698	694	r->u.thread.running = running;
699	695	debug_event(adapter->rec_dbf, 6, r, sizeof(*r));
700	696	spin_unlock_irqrestore(&adapter->rec_dbf_lock, flags);
	697	+}
	698	+
	699	+/**
	700	+ * zfcp_rec_dbf_event_thread - trace event related to recovery thread operation
	701	+ * @id2: identifier for event
	702	+ * @adapter: adapter
	703	+ * This function assumes that the caller does not hold erp_lock.
	704	+ */
	705	+void zfcp_rec_dbf_event_thread_lock(u8 id2, struct zfcp_adapter *adapter)
	706	+{
	707	+ unsigned long flags;
	708	+
	709	+ read_lock_irqsave(&adapter->erp_lock, flags);
	710	+ zfcp_rec_dbf_event_thread(id2, adapter);
	711	+ read_unlock_irqrestore(&adapter->erp_lock, flags);
701	712	}
702	713
703	714	static void zfcp_rec_dbf_event_target(u8 id2, void *ref,
...	...	@@ -783,7 +783,7 @@
783	783
784	784	zfcp_erp_action_to_ready(erp_action);
785	785	up(&adapter->erp_ready_sem);
786		- zfcp_rec_dbf_event_thread(2, adapter, 0);
	786	+ zfcp_rec_dbf_event_thread(2, adapter);
787	787	}
788	788
789	789	/*
...	...	@@ -995,7 +995,7 @@
995	995
996	996	atomic_set_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_KILL, &adapter->status);
997	997	up(&adapter->erp_ready_sem);
998		- zfcp_rec_dbf_event_thread(2, adapter, 1);
	998	+ zfcp_rec_dbf_event_thread_lock(2, adapter);
999	999
1000	1000	wait_event(adapter->erp_thread_wqh,
1001	1001	!atomic_test_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP,
1002	1002
...	...	@@ -1050,9 +1050,9 @@
1050	1050	* no action in 'ready' queue to be processed and
1051	1051	* thread is not to be killed
1052	1052	*/
1053		- zfcp_rec_dbf_event_thread(4, adapter, 1);
	1053	+ zfcp_rec_dbf_event_thread_lock(4, adapter);
1054	1054	down_interruptible(&adapter->erp_ready_sem);
1055		- zfcp_rec_dbf_event_thread(5, adapter, 1);
	1055	+ zfcp_rec_dbf_event_thread_lock(5, adapter);
1056	1056	}
1057	1057
1058	1058	atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP, &adapter->status);
1059	1059
...	...	@@ -2062,9 +2062,9 @@
2062	2062	* _must_ be the one belonging to the 'exchange config
2063	2063	* data' request.
2064	2064	*/
2065		- zfcp_rec_dbf_event_thread(6, adapter, 1);
	2065	+ zfcp_rec_dbf_event_thread_lock(6, adapter);
2066	2066	down(&adapter->erp_ready_sem);
2067		- zfcp_rec_dbf_event_thread(7, adapter, 1);
	2067	+ zfcp_rec_dbf_event_thread_lock(7, adapter);
2068	2068	if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) {
2069	2069	ZFCP_LOG_INFO("error: exchange of configuration data "
2070	2070	"for adapter %s timed out\n",
2071	2071
...	...	@@ -2118,9 +2118,9 @@
2118	2118	}
2119	2119
2120	2120	ret = ZFCP_ERP_SUCCEEDED;
2121		- zfcp_rec_dbf_event_thread(8, adapter, 1);
	2121	+ zfcp_rec_dbf_event_thread_lock(8, adapter);
2122	2122	down(&adapter->erp_ready_sem);
2123		- zfcp_rec_dbf_event_thread(9, adapter, 1);
	2123	+ zfcp_rec_dbf_event_thread_lock(9, adapter);
2124	2124	if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) {
2125	2125	ZFCP_LOG_INFO("error: exchange port data timed out (adapter "
2126	2126	"%s)\n", zfcp_get_busid_by_adapter(adapter));
...	...	@@ -2876,7 +2876,7 @@
2876	2876	/* finally put it into 'ready' queue and kick erp thread */
2877	2877	list_add_tail(&erp_action->list, &adapter->erp_ready_head);
2878	2878	up(&adapter->erp_ready_sem);
2879		- zfcp_rec_dbf_event_thread(1, adapter, 0);
	2879	+ zfcp_rec_dbf_event_thread(1, adapter);
2880	2880	retval = 0;
2881	2881	out:
2882	2882	zfcp_rec_dbf_event_trigger(id, ref, want, need, erp_action,
...	...	@@ -169,8 +169,8 @@
169	169	extern void zfcp_erp_unit_access_changed(struct zfcp_unit , u8, void );
170	170
171	171	/****************************** AUX **************************************/
172		-extern void zfcp_rec_dbf_event_thread(u8 id, struct zfcp_adapter *adapter,
173		- int lock);
	172	+extern void zfcp_rec_dbf_event_thread(u8 id, struct zfcp_adapter *adapter);
	173	+extern void zfcp_rec_dbf_event_thread_lock(u8 id, struct zfcp_adapter *adapter);
174	174	extern void zfcp_rec_dbf_event_adapter(u8 id, void ref, struct zfcp_adapter );
175	175	extern void zfcp_rec_dbf_event_port(u8 id, void ref, struct zfcp_port port);
176	176	extern void zfcp_rec_dbf_event_unit(u8 id, void ref, struct zfcp_unit unit);