[PATCH 19/20] crypto: caam - consolidate memory barriers from job ring en/dequeue
From: Kim Phillips <hidden>
Date: 2012-06-23 00:50:57
Subsystem:
crypto api, freescale caam (cryptographic acceleration and assurance module) driver, the rest · Maintainers:
Herbert Xu, "David S. Miller", Horia Geantă, Pankaj Gupta, Gaurav Jain, Linus Torvalds
Memory barriers are implied by the i/o register write implementation (at least on Power). So we can remove the redundant wmb() in caam_jr_enqueue, and, in dequeue(), hoist the h/w done notification write up to before we need to increment the head of the ring, and save an smp_mb. Signed-off-by: Kim Phillips <redacted> --- drivers/crypto/caam/jr.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c
index 7ae5e51..0adaad1 100644
--- a/drivers/crypto/caam/jr.c
+++ b/drivers/crypto/caam/jr.c@@ -94,7 +94,8 @@ static void caam_jr_dequeue(unsigned long devarg) userdesc = jrp->entinfo[sw_idx].desc_addr_virt; userstatus = jrp->outring[hw_idx].jrstatus; - smp_mb(); + /* set done */ + wr_reg32(&jrp->rregs->outring_rmvd, 1); jrp->out_ring_read_index = (jrp->out_ring_read_index + 1) & (JOBR_DEPTH - 1);
@@ -114,9 +115,6 @@ static void caam_jr_dequeue(unsigned long devarg) jrp->tail = tail; } - /* set done */ - wr_reg32(&jrp->rregs->outring_rmvd, 1); - spin_unlock_bh(&jrp->outlock); /* Finally, execute user's callback */
@@ -265,8 +263,6 @@ int caam_jr_enqueue(struct device *dev, u32 *desc, (JOBR_DEPTH - 1); jrp->head = (head + 1) & (JOBR_DEPTH - 1); - wmb(); - wr_reg32(&jrp->rregs->inpring_jobadd, 1); spin_unlock(&jrp->inplock);
--
1.7.11.1