hpsa: use atomics for commands_outstanding
Use atomics for commands_outstanding instead of protecting with spin locks.
Signed-off-by: Don Brace <don.brace@pmcs.com>
Signed-off-by: Stephen M. Cameron <stephenmcameron@gmail.com>
Reviewed-by: Joe Handzik <joseph.t.handzik@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h
index 80fa9a9..8e06d9e 100644
--- a/drivers/scsi/hpsa.h
+++ b/drivers/scsi/hpsa.h
@@ -118,7 +118,7 @@
struct CfgTable __iomem *cfgtable;
int interrupts_enabled;
int max_commands;
- int commands_outstanding;
+ atomic_t commands_outstanding;
# define PERF_MODE_INT 0
# define DOORBELL_INT 1
# define SIMPLE_MODE_INT 2
@@ -395,7 +395,7 @@
static unsigned long SA5_performant_completed(struct ctlr_info *h, u8 q)
{
struct reply_queue_buffer *rq = &h->reply_queue[q];
- unsigned long flags, register_value = FIFO_EMPTY;
+ unsigned long register_value = FIFO_EMPTY;
/* msi auto clears the interrupt pending bit. */
if (!(h->msi_vector || h->msix_vector)) {
@@ -413,9 +413,7 @@
if ((rq->head[rq->current_entry] & 1) == rq->wraparound) {
register_value = rq->head[rq->current_entry];
rq->current_entry++;
- spin_lock_irqsave(&h->lock, flags);
- h->commands_outstanding--;
- spin_unlock_irqrestore(&h->lock, flags);
+ atomic_dec(&h->commands_outstanding);
} else {
register_value = FIFO_EMPTY;
}
@@ -433,11 +431,7 @@
*/
static unsigned long SA5_fifo_full(struct ctlr_info *h)
{
- if (h->commands_outstanding >= h->max_commands)
- return 1;
- else
- return 0;
-
+ return atomic_read(&h->commands_outstanding) >= h->max_commands;
}
/*
* returns value read from hardware.
@@ -448,13 +442,9 @@
{
unsigned long register_value
= readl(h->vaddr + SA5_REPLY_PORT_OFFSET);
- unsigned long flags;
- if (register_value != FIFO_EMPTY) {
- spin_lock_irqsave(&h->lock, flags);
- h->commands_outstanding--;
- spin_unlock_irqrestore(&h->lock, flags);
- }
+ if (register_value != FIFO_EMPTY)
+ atomic_dec(&h->commands_outstanding);
#ifdef HPSA_DEBUG
if (register_value != FIFO_EMPTY)
@@ -510,7 +500,6 @@
{
u64 register_value;
struct reply_queue_buffer *rq = &h->reply_queue[q];
- unsigned long flags;
BUG_ON(q >= h->nreply_queues);
@@ -528,9 +517,7 @@
wmb();
writel((q << 24) | rq->current_entry, h->vaddr +
IOACCEL_MODE1_CONSUMER_INDEX);
- spin_lock_irqsave(&h->lock, flags);
- h->commands_outstanding--;
- spin_unlock_irqrestore(&h->lock, flags);
+ atomic_dec(&h->commands_outstanding);
}
return (unsigned long) register_value;
}