wil6210: branch prediction hints

Mark expected branches using likely()/unlikely().
Do it on high performance route - data path and interrupts

Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

2 files changed, 33 insertions, 32 deletions

diff --git a/drivers/net/wireless/ath/wil6210/interrupt.c b/drivers/net/wireless/ath/wil6210/interrupt.c
index d5a651bb800e..28ffc18466c4 100644
--- a/drivers/net/wireless/ath/wil6210/interrupt.c
+++ b/drivers/net/wireless/ath/wil6210/interrupt.c
@@ -226,7 +226,7 @@ static irqreturn_t wil6210_irq_rx(int irq, void *cookie)
         trace_wil6210_irq_rx(isr);
         wil_dbg_irq(wil, "ISR RX 0x%08x\n", isr);
 
-        if (!isr) {
+        if (unlikely(!isr)) {
                 wil_err(wil, "spurious IRQ: RX\n");
                 return IRQ_NONE;
         }
@@ -239,17 +239,18 @@ static irqreturn_t wil6210_irq_rx(int irq, void *cookie)
          * action is always the same - should empty the accumulated
          * packets from the RX ring.
          */
-        if (isr & (BIT_DMA_EP_RX_ICR_RX_DONE | BIT_DMA_EP_RX_ICR_RX_HTRSH)) {
+        if (likely(isr & (BIT_DMA_EP_RX_ICR_RX_DONE |
+                          BIT_DMA_EP_RX_ICR_RX_HTRSH))) {
                 wil_dbg_irq(wil, "RX done\n");
 
-                if (isr & BIT_DMA_EP_RX_ICR_RX_HTRSH)
+                if (unlikely(isr & BIT_DMA_EP_RX_ICR_RX_HTRSH))
                         wil_err_ratelimited(wil,
                                             "Received \"Rx buffer is in risk of overflow\" interrupt\n");
 
                 isr &= ~(BIT_DMA_EP_RX_ICR_RX_DONE |
                          BIT_DMA_EP_RX_ICR_RX_HTRSH);
-                if (test_bit(wil_status_reset_done, wil->status)) {
-                        if (test_bit(wil_status_napi_en, wil->status)) {
+                if (likely(test_bit(wil_status_reset_done, wil->status))) {
+                        if (likely(test_bit(wil_status_napi_en, wil->status))) {
                                 wil_dbg_txrx(wil, "NAPI(Rx) schedule\n");
                                 need_unmask = false;
                                 napi_schedule(&wil->napi_rx);
@@ -262,7 +263,7 @@ static irqreturn_t wil6210_irq_rx(int irq, void *cookie)
                 }
         }
 
-        if (isr)
+        if (unlikely(isr))
                 wil_err(wil, "un-handled RX ISR bits 0x%08x\n", isr);
 
         /* Rx IRQ will be enabled when NAPI processing finished */
@@ -286,19 +287,19 @@ static irqreturn_t wil6210_irq_tx(int irq, void *cookie)
         trace_wil6210_irq_tx(isr);
         wil_dbg_irq(wil, "ISR TX 0x%08x\n", isr);
 
-        if (!isr) {
+        if (unlikely(!isr)) {
                 wil_err(wil, "spurious IRQ: TX\n");
                 return IRQ_NONE;
         }
 
         wil6210_mask_irq_tx(wil);
 
-        if (isr & BIT_DMA_EP_TX_ICR_TX_DONE) {
+        if (likely(isr & BIT_DMA_EP_TX_ICR_TX_DONE)) {
                 wil_dbg_irq(wil, "TX done\n");
                 isr &= ~BIT_DMA_EP_TX_ICR_TX_DONE;
                 /* clear also all VRING interrupts */
                 isr &= ~(BIT(25) - 1UL);
-                if (test_bit(wil_status_reset_done, wil->status)) {
+                if (likely(test_bit(wil_status_reset_done, wil->status))) {
                         wil_dbg_txrx(wil, "NAPI(Tx) schedule\n");
                         need_unmask = false;
                         napi_schedule(&wil->napi_tx);
@@ -307,7 +308,7 @@ static irqreturn_t wil6210_irq_tx(int irq, void *cookie)
                 }
         }
 
-        if (isr)
+        if (unlikely(isr))
                 wil_err(wil, "un-handled TX ISR bits 0x%08x\n", isr);
 
         /* Tx IRQ will be enabled when NAPI processing finished */
@@ -496,11 +497,11 @@ static irqreturn_t wil6210_hardirq(int irq, void *cookie)
         /**
          * pseudo_cause is Clear-On-Read, no need to ACK
          */
-        if ((pseudo_cause == 0) || ((pseudo_cause & 0xff) == 0xff))
+        if (unlikely((pseudo_cause == 0) || ((pseudo_cause & 0xff) == 0xff)))
                 return IRQ_NONE;
 
         /* FIXME: IRQ mask debug */
-        if (wil6210_debug_irq_mask(wil, pseudo_cause))
+        if (unlikely(wil6210_debug_irq_mask(wil, pseudo_cause)))
                 return IRQ_NONE;
 
         trace_wil6210_irq_pseudo(pseudo_cause);
diff --git a/drivers/net/wireless/ath/wil6210/txrx.c b/drivers/net/wireless/ath/wil6210/txrx.c
index 779d8369f9bc..7e119d0d8454 100644
--- a/drivers/net/wireless/ath/wil6210/txrx.c
+++ b/drivers/net/wireless/ath/wil6210/txrx.c
@@ -370,11 +370,11 @@ static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
 
         BUILD_BUG_ON(sizeof(struct vring_rx_desc) > sizeof(skb->cb));
 
-        if (wil_vring_is_empty(vring))
+        if (unlikely(wil_vring_is_empty(vring)))
                 return NULL;
 
         _d = &vring->va[vring->swhead].rx;
-        if (!(_d->dma.status & RX_DMA_STATUS_DU)) {
+        if (unlikely(!(_d->dma.status & RX_DMA_STATUS_DU))) {
                 /* it is not error, we just reached end of Rx done area */
                 return NULL;
         }
@@ -394,7 +394,7 @@ static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
         wil_hex_dump_txrx("Rx ", DUMP_PREFIX_NONE, 32, 4,
                           (const void *)d, sizeof(*d), false);
 
-        if (dmalen > sz) {
+        if (unlikely(dmalen > sz)) {
                 wil_err(wil, "Rx size too large: %d bytes!\n", dmalen);
                 kfree_skb(skb);
                 return NULL;
@@ -423,14 +423,14 @@ static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
          * in Rx descriptor. If type is not data, it is 802.11 frame as is
          */
         ftype = wil_rxdesc_ftype(d) << 2;
-        if (ftype != IEEE80211_FTYPE_DATA) {
+        if (unlikely(ftype != IEEE80211_FTYPE_DATA)) {
                 wil_dbg_txrx(wil, "Non-data frame ftype 0x%08x\n", ftype);
                 /* TODO: process it */
                 kfree_skb(skb);
                 return NULL;
         }
 
-        if (skb->len < ETH_HLEN) {
+        if (unlikely(skb->len < ETH_HLEN)) {
                 wil_err(wil, "Short frame, len = %d\n", skb->len);
                 /* TODO: process it (i.e. BAR) */
                 kfree_skb(skb);
@@ -441,9 +441,9 @@ static struct sk_buff *wil_vring_reap_rx(struct wil6210_priv *wil,
          * and in case of error drop the packet
          * higher stack layers will handle retransmission (if required)
          */
-        if (d->dma.status & RX_DMA_STATUS_L4I) {
+        if (likely(d->dma.status & RX_DMA_STATUS_L4I)) {
                 /* L4 protocol identified, csum calculated */
-                if ((d->dma.error & RX_DMA_ERROR_L4_ERR) == 0)
+                if (likely((d->dma.error & RX_DMA_ERROR_L4_ERR) == 0))
                         skb->ip_summed = CHECKSUM_UNNECESSARY;
                 /* If HW reports bad checksum, let IP stack re-check it
                  * For example, HW don't understand Microsoft IP stack that
@@ -472,7 +472,7 @@ static int wil_rx_refill(struct wil6210_priv *wil, int count)
                         (next_tail != v->swhead) && (count-- > 0);
                         v->swtail = next_tail) {
                 rc = wil_vring_alloc_skb(wil, v, v->swtail, headroom);
-                if (rc) {
+                if (unlikely(rc)) {
                         wil_err(wil, "Error %d in wil_rx_refill[%d]\n",
                                 rc, v->swtail);
                         break;
@@ -534,7 +534,7 @@ void wil_rx_handle(struct wil6210_priv *wil, int *quota)
         struct vring *v = &wil->vring_rx;
         struct sk_buff *skb;
 
-        if (!v->va) {
+        if (unlikely(!v->va)) {
                 wil_err(wil, "Rx IRQ while Rx not yet initialized\n");
                 return;
         }
@@ -927,7 +927,7 @@ static int __wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
         if (unlikely(!txdata->enabled))
                 return -EINVAL;
 
-        if (avail < 1 + nr_frags) {
+        if (unlikely(avail < 1 + nr_frags)) {
                 wil_err_ratelimited(wil,
                                     "Tx ring[%2d] full. No space for %d fragments\n",
                                     vring_index, 1 + nr_frags);
@@ -948,7 +948,7 @@ static int __wil_tx_vring(struct wil6210_priv *wil, struct vring *vring,
         /* 1-st segment */
         wil_tx_desc_map(d, pa, skb_headlen(skb), vring_index);
         /* Process TCP/UDP checksum offloading */
-        if (wil_tx_desc_offload_cksum_set(wil, d, skb)) {
+        if (unlikely(wil_tx_desc_offload_cksum_set(wil, d, skb))) {
                 wil_err(wil, "Tx[%2d] Failed to set cksum, drop packet\n",
                         vring_index);
                 goto dma_error;
@@ -1051,18 +1051,18 @@ netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
         int rc;
 
         wil_dbg_txrx(wil, "%s()\n", __func__);
-        if (!test_bit(wil_status_fwready, wil->status)) {
+        if (unlikely(!test_bit(wil_status_fwready, wil->status))) {
                 if (!pr_once_fw) {
                         wil_err(wil, "FW not ready\n");
                         pr_once_fw = true;
                 }
                 goto drop;
         }
-        if (!test_bit(wil_status_fwconnected, wil->status)) {
+        if (unlikely(!test_bit(wil_status_fwconnected, wil->status))) {
                 wil_err(wil, "FW not connected\n");
                 goto drop;
         }
-        if (wil->wdev->iftype == NL80211_IFTYPE_MONITOR) {
+        if (unlikely(wil->wdev->iftype == NL80211_IFTYPE_MONITOR)) {
                 wil_err(wil, "Xmit in monitor mode not supported\n");
                 goto drop;
         }
@@ -1078,7 +1078,7 @@ netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
                 else
                         vring = wil_tx_bcast(wil, skb);
         }
-        if (!vring) {
+        if (unlikely(!vring)) {
                 wil_dbg_txrx(wil, "No Tx VRING found for %pM\n", eth->h_dest);
                 goto drop;
         }
@@ -1086,7 +1086,7 @@ netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev)
         rc = wil_tx_vring(wil, vring, skb);
 
         /* do we still have enough room in the vring? */
-        if (wil_vring_avail_tx(vring) < wil_vring_wmark_low(vring)) {
+        if (unlikely(wil_vring_avail_tx(vring) < wil_vring_wmark_low(vring))) {
                 netif_tx_stop_all_queues(wil_to_ndev(wil));
                 wil_dbg_txrx(wil, "netif_tx_stop : ring full\n");
         }
@@ -1142,12 +1142,12 @@ int wil_tx_complete(struct wil6210_priv *wil, int ringid)
         struct wil_net_stats *stats = &wil->sta[cid].stats;
         volatile struct vring_tx_desc *_d;
 
-        if (!vring->va) {
+        if (unlikely(!vring->va)) {
                 wil_err(wil, "Tx irq[%d]: vring not initialized\n", ringid);
                 return 0;
         }
 
-        if (!txdata->enabled) {
+        if (unlikely(!txdata->enabled)) {
                 wil_info(wil, "Tx irq[%d]: vring disabled\n", ringid);
                 return 0;
         }
@@ -1165,7 +1165,7 @@ int wil_tx_complete(struct wil6210_priv *wil, int ringid)
                 /* TODO: check we are not past head */
 
                 _d = &vring->va[lf].tx;
-                if (!(_d->dma.status & TX_DMA_STATUS_DU))
+                if (unlikely(!(_d->dma.status & TX_DMA_STATUS_DU)))
                         break;
 
                 new_swtail = (lf + 1) % vring->size;
@@ -1193,7 +1193,7 @@ int wil_tx_complete(struct wil6210_priv *wil, int ringid)
                         wil_txdesc_unmap(dev, d, ctx);
 
                         if (skb) {
-                                if (d->dma.error == 0) {
+                                if (likely(d->dma.error == 0)) {
                                         ndev->stats.tx_packets++;
                                         stats->tx_packets++;
                                         ndev->stats.tx_bytes += skb->len;