From 632be1942d084df89066986e74b56ff0110dd621 Mon Sep 17 00:00:00 2001 From: Hariprasad Shenai Date: Tue, 8 Dec 2015 10:09:13 +0530 Subject: [PATCH] cxgb4: Use ACCES_ONCE macro to read queue's consumer index Use helper macro ACCESS_ONCE() to load from the SGE status page to prevent the compiler loading multiple times. Based on original work by Mike Werner Signed-off-by: Hariprasad Shenai Signed-off-by: David S. Miller --- drivers/net/ethernet/chelsio/cxgb4/sge.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c index 48d8fbb..1076c35 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c @@ -406,7 +406,7 @@ static void free_tx_desc(struct adapter *adap, struct sge_txq *q, */ static inline int reclaimable(const struct sge_txq *q) { - int hw_cidx = ntohs(q->stat->cidx); + int hw_cidx = ntohs(ACCESS_ONCE(q->stat->cidx)); hw_cidx -= q->cidx; return hw_cidx < 0 ? hw_cidx + q->size : hw_cidx; } @@ -1320,7 +1320,7 @@ out_free: dev_kfree_skb_any(skb); */ static inline void reclaim_completed_tx_imm(struct sge_txq *q) { - int hw_cidx = ntohs(q->stat->cidx); + int hw_cidx = ntohs(ACCESS_ONCE(q->stat->cidx)); int reclaim = hw_cidx - q->cidx; if (reclaim < 0) -- 2.7.4