[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>
This commit is contained in:
Christof Schmitt 2008-05-19 12:17:47 +02:00 committed by James Bottomley
parent 7337891f38
commit aa0fec6239
3 changed files with 28 additions and 17 deletions

View File

@ -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,

View File

@ -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,

View File

@ -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);