Commit aa0fec62 authored by Christof Schmitt's avatar Christof Schmitt Committed by James Bottomley
Browse files

[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: default avatarChristof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: default avatarMartin Peschke <mp3@de.ibm.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
parent 7337891f

drivers/s390/scsi/zfcp_dbf.c

+17 −6
Original line number Diff line number Diff line
@@ -670,24 +670,20 @@ static struct debug_view zfcp_rec_dbf_view = { 
 * 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));
@@ -700,6 +696,21 @@ void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter, int lock) 
	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,

				      struct zfcp_adapter *adapter,

				      atomic_t *status, atomic_t *erp_count,

drivers/s390/scsi/zfcp_erp.c

+9 −9
Original line number Diff line number Diff line
@@ -783,7 +783,7 @@ zfcp_erp_action_ready(struct zfcp_erp_action *erp_action) 


	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 @@ zfcp_erp_thread_kill(struct zfcp_adapter *adapter) 


	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 @@ zfcp_erp_thread(void *data) 
		 * 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 @@ zfcp_erp_adapter_strategy_open_fsf_xconfig(struct zfcp_erp_action *erp_action) 
		 * _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 @@ zfcp_erp_adapter_strategy_open_fsf_xport(struct zfcp_erp_action *erp_action) 
	}



	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 @@ static int zfcp_erp_action_enqueue(int want, struct zfcp_adapter *adapter, 
	/* 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,

drivers/s390/scsi/zfcp_ext.h

+2 −2
Original line number Diff line number Diff line
@@ -169,8 +169,8 @@ extern void zfcp_erp_port_access_changed(struct zfcp_port *, u8, void *); 
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);

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