mailbox: bcm-pdc: Try to improve branch prediction
Use likely/unlikely directives to improve branch prediction.
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
diff --git a/drivers/mailbox/bcm-pdc-mailbox.c b/drivers/mailbox/bcm-pdc-mailbox.c
index 2195760..7ed3f02 100644
--- a/drivers/mailbox/bcm-pdc-mailbox.c
+++ b/drivers/mailbox/bcm-pdc-mailbox.c
@@ -834,7 +834,7 @@ static int pdc_rx_list_init(struct pdc_state *pdcs, struct scatterlist *dst_sg,
/* allocate a buffer for the dma rx status */
vaddr = dma_pool_zalloc(pdcs->rx_buf_pool, GFP_ATOMIC, &daddr);
- if (!vaddr)
+ if (unlikely(!vaddr))
return -ENOMEM;
/*
@@ -945,14 +945,14 @@ static irqreturn_t pdc_irq_handler(int irq, void *cookie)
struct pdc_state *pdcs = cookie;
u32 intstatus = ioread32(pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET);
- if (intstatus & PDC_RCVINTEN_0)
+ if (likely(intstatus & PDC_RCVINTEN_0))
set_bit(PDC_RCVINT_0, &pdcs->intstatus);
/* Clear interrupt flags in device */
iowrite32(intstatus, pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET);
/* Wakeup IRQ thread */
- if (pdcs && (irq == pdcs->pdc_irq) && (intstatus & PDC_INTMASK))
+ if (likely(pdcs && (irq == pdcs->pdc_irq) && (intstatus & PDC_INTMASK)))
return IRQ_WAKE_THREAD;
return IRQ_NONE;
@@ -976,7 +976,7 @@ static irqreturn_t pdc_irq_thread(int irq, void *cookie)
bool rx_int;
rx_int = test_and_clear_bit(PDC_RCVINT_0, &pdcs->intstatus);
- if (pdcs && rx_int) {
+ if (likely(pdcs && rx_int)) {
dev_dbg(&pdcs->pdev->dev,
"%s() got irq %d with rx_int %s",
__func__, irq, rx_int ? "set" : "clear");
@@ -1007,14 +1007,14 @@ static int pdc_ring_init(struct pdc_state *pdcs, int ringset)
/* Allocate tx ring */
tx.vbase = dma_pool_zalloc(pdcs->ring_pool, GFP_KERNEL, &tx.dmabase);
- if (!tx.vbase) {
+ if (unlikely(!tx.vbase)) {
err = -ENOMEM;
goto done;
}
/* Allocate rx ring */
rx.vbase = dma_pool_zalloc(pdcs->ring_pool, GFP_KERNEL, &rx.dmabase);
- if (!rx.vbase) {
+ if (unlikely(!rx.vbase)) {
err = -ENOMEM;
goto fail_dealloc;
}
@@ -1219,21 +1219,21 @@ static int pdc_send_data(struct mbox_chan *chan, void *data)
u32 tx_desc_req;
u32 rx_desc_req;
- if (mssg->type != BRCM_MESSAGE_SPU)
+ if (unlikely(mssg->type != BRCM_MESSAGE_SPU))
return -ENOTSUPP;
src_nent = sg_nents(mssg->spu.src);
- if (src_nent) {
+ if (likely(src_nent)) {
nent = dma_map_sg(dev, mssg->spu.src, src_nent, DMA_TO_DEVICE);
- if (nent == 0)
+ if (unlikely(nent == 0))
return -EIO;
}
dst_nent = sg_nents(mssg->spu.dst);
- if (dst_nent) {
+ if (likely(dst_nent)) {
nent = dma_map_sg(dev, mssg->spu.dst, dst_nent,
DMA_FROM_DEVICE);
- if (nent == 0) {
+ if (unlikely(nent == 0)) {
dma_unmap_sg(dev, mssg->spu.src, src_nent,
DMA_TO_DEVICE);
return -EIO;
@@ -1251,7 +1251,7 @@ static int pdc_send_data(struct mbox_chan *chan, void *data)
*/
tx_desc_req = pdc_desc_count(mssg->spu.src);
rx_desc_req = pdc_desc_count(mssg->spu.dst);
- if (pdc_rings_full(pdcs, tx_desc_req, rx_desc_req + 1))
+ if (unlikely(pdc_rings_full(pdcs, tx_desc_req, rx_desc_req + 1)))
return -ENOSPC;
/* Create rx descriptors to SPU catch response */
@@ -1262,7 +1262,7 @@ static int pdc_send_data(struct mbox_chan *chan, void *data)
err |= pdc_tx_list_sg_add(pdcs, mssg->spu.src);
err |= pdc_tx_list_final(pdcs); /* initiate transfer */
- if (err)
+ if (unlikely(err))
dev_err(&pdcs->pdev->dev,
"%s failed with error %d", __func__, err);