From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ryder Lee Subject: [PATCH v3 2/4] mt76: add unlikely() for dma_mapping_error() check Date: Mon, 1 Apr 2019 15:16:42 +0800 Message-ID: <87b458bb8525f3fe31cc96fef71df8542a01e1ab.1554102584.git.ryder.lee@mediatek.com> References: Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Lorenzo Bianconi , Felix Fietkau Cc: Roy Luo , Sean Wang , Nelson Chang , YF Luo , Kai Lin , Rorscha Yang , Kyle Lee , Miller Shen , Haipin Liang , KL Huang , YH chen , linux-wireless@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Ryder Lee List-Id: linux-mediatek@lists.infradead.org In the tx/rx fastpath, the funciton dma_map_single() rarely fails. This adds unlikely() optimization to this error check conditional. Signed-off-by: Ryder Lee --- drivers/net/wireless/mediatek/mt76/dma.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c index 8a4b935..6f3ef09 100644 --- a/drivers/net/wireless/mediatek/mt76/dma.c +++ b/drivers/net/wireless/mediatek/mt76/dma.c @@ -272,7 +272,7 @@ addr = dma_map_single(dev->dev, skb->data, skb->len, DMA_TO_DEVICE); - if (dma_mapping_error(dev->dev, addr)) + if (unlikely(dma_mapping_error(dev->dev, addr))) return -ENOMEM; buf.addr = addr; @@ -315,7 +315,7 @@ len = skb_headlen(skb); addr = dma_map_single(dev->dev, skb->data, len, DMA_TO_DEVICE); - if (dma_mapping_error(dev->dev, addr)) + if (unlikely(dma_mapping_error(dev->dev, addr))) goto free; tx_info.buf[n].addr = t->dma_addr; @@ -329,7 +329,7 @@ addr = dma_map_single(dev->dev, iter->data, iter->len, DMA_TO_DEVICE); - if (dma_mapping_error(dev->dev, addr)) + if (unlikely(dma_mapping_error(dev->dev, addr))) goto unmap; tx_info.buf[n].addr = addr; @@ -386,7 +386,7 @@ break; addr = dma_map_single(dev->dev, buf, len, DMA_FROM_DEVICE); - if (dma_mapping_error(dev->dev, addr)) { + if (unlikely(dma_mapping_error(dev->dev, addr))) { skb_free_frag(buf); break; } -- 1.9.1