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From: Ivan Vecera <ivecera@redhat.com>
To: netdev@vger.kernel.org
Cc: rmody@brocade.com
Subject: [PATCH net] bna: fix performance regression
Date: Tue, 29 Jul 2014 16:29:30 +0200	[thread overview]
Message-ID: <1406644170-4693-1-git-send-email-ivecera@redhat.com> (raw)

The recent commit "e29aa33 bna: Enable Multi Buffer RX" is causing
a performance regression. It does not properly update 'cmpl' pointer
at the end of the loop in NAPI handler bnad_cq_process(). The result is
only one packet / per NAPI-schedule is processed.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
 drivers/net/ethernet/brocade/bna/bnad.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/brocade/bna/bnad.c b/drivers/net/ethernet/brocade/bna/bnad.c
index 3a77f9e..556aab7 100644
--- a/drivers/net/ethernet/brocade/bna/bnad.c
+++ b/drivers/net/ethernet/brocade/bna/bnad.c
@@ -600,9 +600,9 @@ bnad_cq_process(struct bnad *bnad, struct bna_ccb *ccb, int budget)
 	prefetch(bnad->netdev);
 
 	cq = ccb->sw_q;
-	cmpl = &cq[ccb->producer_index];
 
 	while (packets < budget) {
+		cmpl = &cq[ccb->producer_index];
 		if (!cmpl->valid)
 			break;
 		/* The 'valid' field is set by the adapter, only after writing
-- 
1.8.5.5

             reply	other threads:[~2014-07-29 14:29 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-29 14:29 Ivan Vecera [this message]
2014-07-31  2:10 ` [PATCH net] bna: fix performance regression David Miller

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