crypto: caam - one tasklet per job ring

there is no noticeable benefit for multiple cores to process one
job ring's output ring: in fact, we can benefit from cache effects
of having the back-half stay on the core that receives a particular
ring's interrupts, and further relax general contention and the
locking involved with reading outring_used, since tasklets run
atomically.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

2 files changed, 6 insertions, 9 deletions

diff --git a/drivers/crypto/caam/intern.h b/drivers/crypto/caam/intern.h
index ed2b739f934b..5cd4c1b268a1 100644
--- a/drivers/crypto/caam/intern.h
+++ b/drivers/crypto/caam/intern.h
@@ -43,7 +43,7 @@ struct caam_drv_private_jr {
         struct device *parentdev;       /* points back to controller dev */
         int ridx;
         struct caam_job_ring __iomem *rregs;    /* JobR's register space */
-        struct tasklet_struct irqtask[NR_CPUS];
+        struct tasklet_struct irqtask;
         int irq;                        /* One per queue */
         int assign;                     /* busy/free */
 
diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c
index 0adaad1b8cf7..7074a1a29e8b 100644
--- a/drivers/crypto/caam/jr.c
+++ b/drivers/crypto/caam/jr.c
@@ -43,7 +43,7 @@ static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
         wr_reg32(&jrp->rregs->jrintstatus, irqstate);
 
         preempt_disable();
-        tasklet_schedule(&jrp->irqtask[smp_processor_id()]);
+        tasklet_schedule(&jrp->irqtask);
         preempt_enable();
 
         return IRQ_HANDLED;
@@ -322,11 +322,9 @@ static int caam_jr_init(struct device *dev)
 
         jrp = dev_get_drvdata(dev);
 
-        /* Connect job ring interrupt handler. */
-        for_each_possible_cpu(i)
-                tasklet_init(&jrp->irqtask[i], caam_jr_dequeue,
-                             (unsigned long)dev);
+        tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
 
+        /* Connect job ring interrupt handler. */
         error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED,
                             "caam-jobr", dev);
         if (error) {
@@ -416,12 +414,11 @@ int caam_jr_shutdown(struct device *dev)
 {
         struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
         dma_addr_t inpbusaddr, outbusaddr;
-        int ret, i;
+        int ret;
 
         ret = caam_reset_hw_jr(dev);
 
-        for_each_possible_cpu(i)
-                tasklet_kill(&jrp->irqtask[i]);
+        tasklet_kill(&jrp->irqtask);
 
         /* Release interrupt */
         free_irq(jrp->irq, dev);