[PATCH 4/5] net: macb: Remove 'unlikely' optimization

From: Soren Brinkmann
Date: Sun May 04 2014 - 18:44:42 EST


Coverage data suggests that the unlikely case of receiving data while
the receive handler is running may not be that unlikely.
Coverage data after running iperf for a while:
91320: 891: work_done = bp->macbgem_ops.mog_rx(bp, budget);
91320: 892: if (work_done < budget) {
2362: 893: napi_complete(napi);
-: 894:
-: 895: /* Packets received while interrupts were disabled */
4724: 896: status = macb_readl(bp, RSR);
2362: 897: if (unlikely(status)) {
762: 898: if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
762: 899: macb_writel(bp, ISR, MACB_BIT(RCOMP));
-: 900: napi_reschedule(napi);
-: 901: } else {
1600: 902: macb_writel(bp, IER, MACB_RX_INT_FLAGS);
-: 903: }
-: 904: }

Signed-off-by: Soren Brinkmann <soren.brinkmann@xxxxxxxxxx>
---

drivers/net/ethernet/cadence/macb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
index 3f4b8ee0b0e7..3e13aa31548a 100644
--- a/drivers/net/ethernet/cadence/macb.c
+++ b/drivers/net/ethernet/cadence/macb.c
@@ -893,7 +893,7 @@ static int macb_poll(struct napi_struct *napi, int budget)

/* Packets received while interrupts were disabled */
status = macb_readl(bp, RSR);
- if (unlikely(status)) {
+ if (status) {
if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
macb_writel(bp, ISR, MACB_BIT(RCOMP));
napi_reschedule(napi);
--
1.9.2.1.g06c4abd

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