From:   Stanislaw Gruszka <sgruszka@redhat.com>
To:     Felix Fietkau <nbd@nbd.name>
Cc:     Lorenzo Bianconi <lorenzo.bianconi@redhat.com>,
        linux-wireless@vger.kernel.org,
        Stanislaw Gruszka <sgruszka@redhat.com>
Subject: [PATCH 11/12] mt76usb: allocate urb and sg as linear data
Date:   Thu, 21 Mar 2019 16:25:36 +0100
Message-Id: <20190321152537.19105-12-sgruszka@redhat.com>
In-Reply-To: <20190321152537.19105-1-sgruszka@redhat.com>
References: <20190321152537.19105-1-sgruszka@redhat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-wireless-owner@vger.kernel.org
Precedence: bulk

Alloc sg table at the end of urb structure. This will increase
cache usage.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
---
 drivers/net/wireless/mediatek/mt76/usb.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c
index 0ae69c2fedaf..a80d6abee748 100644
--- a/drivers/net/wireless/mediatek/mt76/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/usb.c
@@ -336,19 +336,19 @@ mt76u_refill_rx(struct mt76_dev *dev, struct urb *urb, int nsgs, gfp_t gfp)
 static int
 mt76u_urb_alloc(struct mt76_dev *dev, struct mt76_queue_entry *e)
 {
-	struct urb *urb;
+	unsigned int size = sizeof(struct urb);
+
+	if (dev->usb.sg_en)
+		size += MT_SG_MAX_SIZE * sizeof(struct scatterlist);
 
-	urb = usb_alloc_urb(0, GFP_KERNEL);
-	if (!urb)
+	e->urb = kzalloc(size, GFP_KERNEL);
+	if (!e->urb)
 		return -ENOMEM;
-	e->urb = urb;
 
-	if (dev->usb.sg_en) {
-		urb->sg = devm_kcalloc(dev->dev, MT_SG_MAX_SIZE,
-				       sizeof(*urb->sg), GFP_KERNEL);
-		if (!urb->sg)
-			return -ENOMEM;
-	}
+	usb_init_urb(e->urb);
+
+	if (dev->usb.sg_en)
+		e->urb->sg = (struct scatterlist *)(e->urb + 1);
 
 	return 0;
 }
-- 
2.20.1