From: Shai Brandes <shaib...@amazon.com>
The unlikely mechanism is used to reduce pipe flush,
caused by a wrong branch prediction.
Moreover, it increases readability by wrapping unexpected errors.
This commit adds unlikely to error checks that are unlikely to happen.
Signed-off-by: Shai Brandes <shaib...@amazon.com>
Reviewed-by: Amit Bernstein <amitb...@amazon.com>
---
drivers/net/ena/base/ena_com.c | 56 +++++++++++++++---------------
drivers/net/ena/base/ena_eth_com.c | 2 +-
2 files changed, 29 insertions(+), 29 deletions(-)
diff --git a/drivers/net/ena/base/ena_com.c b/drivers/net/ena/base/ena_com.c
index a0c88b1a0e..d2de5e172d 100644
--- a/drivers/net/ena/base/ena_com.c
+++ b/drivers/net/ena/base/ena_com.c
@@ -79,7 +79,7 @@ static int ena_com_mem_addr_set(struct ena_com_dev *ena_dev,
struct ena_common_mem_addr *ena_addr,
dma_addr_t addr)
{
- if ((addr & GENMASK_ULL(ena_dev->dma_addr_bits - 1, 0)) != addr) {
+ if (unlikely((addr & GENMASK_ULL(ena_dev->dma_addr_bits - 1, 0)) !=
addr)) {
ena_trc_err(ena_dev, "DMA address has more bits than the device
supports\n");
return ENA_COM_INVAL;
}
@@ -99,7 +99,7 @@ static int ena_com_admin_init_sq(struct ena_com_admin_queue
*admin_queue)
ENA_MEM_ALLOC_COHERENT(admin_queue->q_dmadev, size, sq->entries,
sq->dma_addr,
sq->mem_handle);
- if (!sq->entries) {
+ if (unlikely(!sq->entries)) {
ena_trc_err(ena_dev, "Memory allocation failed\n");
return ENA_COM_NO_MEM;
}
@@ -122,7 +122,7 @@ static int ena_com_admin_init_cq(struct ena_com_admin_queue
*admin_queue)
ENA_MEM_ALLOC_COHERENT(admin_queue->q_dmadev, size, cq->entries,
cq->dma_addr,
cq->mem_handle);
- if (!cq->entries) {
+ if (unlikely(!cq->entries)) {
ena_trc_err(ena_dev, "Memory allocation failed\n");
return ENA_COM_NO_MEM;
}
@@ -147,7 +147,7 @@ static int ena_com_admin_init_aenq(struct ena_com_dev
*ena_dev,
aenq->dma_addr,
aenq->mem_handle);
- if (!aenq->entries) {
+ if (unlikely(!aenq->entries)) {
ena_trc_err(ena_dev, "Memory allocation failed\n");
return ENA_COM_NO_MEM;
}
@@ -233,7 +233,7 @@ static struct ena_comp_ctx
*__ena_com_submit_admin_cmd(struct ena_com_admin_queu
/* In case of queue FULL */
cnt = (u16)ATOMIC32_READ(&admin_queue->outstanding_cmds);
- if (cnt >= admin_queue->q_depth) {
+ if (unlikely(cnt >= admin_queue->q_depth)) {
ena_trc_dbg(admin_queue->ena_dev, "Admin queue is full.\n");
admin_queue->stats.out_of_space++;
return ERR_PTR(ENA_COM_NO_SPACE);
@@ -357,7 +357,7 @@ static int ena_com_init_io_sq(struct ena_com_dev *ena_dev,
io_sq->desc_addr.mem_handle);
}
- if (!io_sq->desc_addr.virt_addr) {
+ if (unlikely(!io_sq->desc_addr.virt_addr)) {
ena_trc_err(ena_dev, "Memory allocation failed\n");
return ENA_COM_NO_MEM;
}
@@ -382,7 +382,7 @@ static int ena_com_init_io_sq(struct ena_com_dev *ena_dev,
if (!io_sq->bounce_buf_ctrl.base_buffer)
io_sq->bounce_buf_ctrl.base_buffer =
ENA_MEM_ALLOC(ena_dev->dmadev, size);
- if (!io_sq->bounce_buf_ctrl.base_buffer) {
+ if (unlikely(!io_sq->bounce_buf_ctrl.base_buffer)) {
ena_trc_err(ena_dev, "Bounce buffer memory allocation
failed\n");
return ENA_COM_NO_MEM;
}
@@ -447,7 +447,7 @@ static int ena_com_init_io_cq(struct ena_com_dev *ena_dev,
ENA_CDESC_RING_SIZE_ALIGNMENT);
}
- if (!io_cq->cdesc_addr.virt_addr) {
+ if (unlikely(!io_cq->cdesc_addr.virt_addr)) {
ena_trc_err(ena_dev, "Memory allocation failed\n");
return ENA_COM_NO_MEM;
}
@@ -577,7 +577,7 @@ static int ena_com_wait_and_process_admin_cq_polling(struct
ena_comp_ctx *comp_c
if (comp_ctx->status != ENA_CMD_SUBMITTED)
break;
- if (ENA_TIME_EXPIRE(timeout)) {
+ if (unlikely(ENA_TIME_EXPIRE(timeout))) {
ena_trc_err(admin_queue->ena_dev,
"Wait for completion (polling) timeout\n");
/* ENA didn't have any completion */
@@ -776,7 +776,7 @@ static int ena_com_config_llq_info(struct ena_com_dev
*ena_dev,
llq_default_cfg->llq_ring_entry_size_value;
rc = ena_com_set_llq(ena_dev);
- if (rc)
+ if (unlikely(rc))
ena_trc_err(ena_dev, "Cannot set LLQ configuration: %d\n", rc);
return rc;
@@ -882,7 +882,7 @@ static u32 ena_com_reg_bar_read32(struct ena_com_dev
*ena_dev, u16 offset)
goto err;
}
- if (read_resp->reg_off != offset) {
+ if (unlikely(read_resp->reg_off != offset)) {
ena_trc_err(ena_dev, "Read failure: wrong offset provided\n");
ret = ENA_MMIO_READ_TIMEOUT;
} else {
@@ -1006,7 +1006,7 @@ static int wait_for_reset_state(struct ena_com_dev
*ena_dev, u32 timeout,
exp_state)
return 0;
- if (ENA_TIME_EXPIRE(timeout_stamp))
+ if (unlikely(ENA_TIME_EXPIRE(timeout_stamp)))
return ENA_COM_TIMER_EXPIRED;
ena_delay_exponential_backoff_us(exp++,
ena_dev->ena_min_poll_delay_us);
@@ -1467,7 +1467,7 @@ int ena_com_get_io_handlers(struct ena_com_dev *ena_dev,
u16 qid,
struct ena_com_io_sq **io_sq,
struct ena_com_io_cq **io_cq)
{
- if (qid >= ENA_TOTAL_NUM_QUEUES) {
+ if (unlikely(qid >= ENA_TOTAL_NUM_QUEUES)) {
ena_trc_err(ena_dev, "Invalid queue number %d but the max is
%d\n",
qid, ENA_TOTAL_NUM_QUEUES);
return ENA_COM_INVAL;
@@ -1575,7 +1575,7 @@ int ena_com_set_aenq_config(struct ena_com_dev *ena_dev,
u32 groups_flag)
int ret;
ret = ena_com_get_feature(ena_dev, &get_resp, ENA_ADMIN_AENQ_CONFIG, 0);
- if (ret) {
+ if (unlikely(ret)) {
ena_trc_info(ena_dev, "Can't get aenq configuration\n");
return ret;
}
@@ -1622,7 +1622,7 @@ int ena_com_get_dma_width(struct ena_com_dev *ena_dev)
ena_trc_dbg(ena_dev, "ENA dma width: %d\n", width);
- if ((width < 32) || width > ENA_MAX_PHYS_ADDR_SIZE_BITS) {
+ if (unlikely(width < 32 || width > ENA_MAX_PHYS_ADDR_SIZE_BITS)) {
ena_trc_err(ena_dev, "DMA width illegal value: %d\n", width);
return ENA_COM_INVAL;
}
@@ -2092,15 +2092,15 @@ int ena_com_admin_init(struct ena_com_dev *ena_dev,
ENA_SPINLOCK_INIT(admin_queue->q_lock);
ret = ena_com_init_comp_ctxt(admin_queue);
- if (ret)
+ if (unlikely(ret))
goto error;
ret = ena_com_admin_init_sq(admin_queue);
- if (ret)
+ if (unlikely(ret))
goto error;
ret = ena_com_admin_init_cq(admin_queue);
- if (ret)
+ if (unlikely(ret))
goto error;
admin_queue->sq.db_addr = (u32 __iomem *)((uintptr_t)ena_dev->reg_bar +
@@ -2133,7 +2133,7 @@ int ena_com_admin_init(struct ena_com_dev *ena_dev,
ENA_REG_WRITE32(ena_dev->bus, aq_caps, ena_dev->reg_bar +
ENA_REGS_AQ_CAPS_OFF);
ENA_REG_WRITE32(ena_dev->bus, acq_caps, ena_dev->reg_bar +
ENA_REGS_ACQ_CAPS_OFF);
ret = ena_com_admin_init_aenq(ena_dev, aenq_handlers);
- if (ret)
+ if (unlikely(ret))
goto error;
admin_queue->ena_dev = ena_dev;
@@ -2153,7 +2153,7 @@ int ena_com_create_io_queue(struct ena_com_dev *ena_dev,
struct ena_com_io_cq *io_cq;
int ret;
- if (ctx->qid >= ENA_TOTAL_NUM_QUEUES) {
+ if (unlikely(ctx->qid >= ENA_TOTAL_NUM_QUEUES)) {
ena_trc_err(ena_dev, "Qid (%d) is bigger than max num of queues
(%d)\n",
ctx->qid, ENA_TOTAL_NUM_QUEUES);
return ENA_COM_INVAL;
@@ -2184,18 +2184,18 @@ int ena_com_create_io_queue(struct ena_com_dev *ena_dev,
ENA_MIN32(ena_dev->tx_max_header_size, SZ_256);
ret = ena_com_init_io_sq(ena_dev, ctx, io_sq);
- if (ret)
+ if (unlikely(ret))
goto error;
ret = ena_com_init_io_cq(ena_dev, ctx, io_cq);
- if (ret)
+ if (unlikely(ret))
goto error;
ret = ena_com_create_io_cq(ena_dev, io_cq);
- if (ret)
+ if (unlikely(ret))
goto error;
ret = ena_com_create_io_sq(ena_dev, io_sq, io_cq->idx);
- if (ret)
+ if (unlikely(ret))
goto destroy_io_cq;
return 0;
@@ -2212,7 +2212,7 @@ void ena_com_destroy_io_queue(struct ena_com_dev
*ena_dev, u16 qid)
struct ena_com_io_sq *io_sq;
struct ena_com_io_cq *io_cq;
- if (qid >= ENA_TOTAL_NUM_QUEUES) {
+ if (unlikely(qid >= ENA_TOTAL_NUM_QUEUES)) {
ena_trc_err(ena_dev, "Qid (%d) is bigger than max num of queues
(%d)\n",
qid, ENA_TOTAL_NUM_QUEUES);
return;
@@ -2513,7 +2513,7 @@ int ena_com_dev_reset(struct ena_com_dev *ena_dev,
rc = wait_for_reset_state(ena_dev, timeout,
ENA_REGS_DEV_STS_RESET_IN_PROGRESS_MASK);
- if (rc != 0) {
+ if (unlikely(rc)) {
ena_trc_err(ena_dev, "Reset indication didn't turn on\n");
return rc;
}
@@ -2521,7 +2521,7 @@ int ena_com_dev_reset(struct ena_com_dev *ena_dev,
/* reset done */
ENA_REG_WRITE32(ena_dev->bus, 0, ena_dev->reg_bar +
ENA_REGS_DEV_CTL_OFF);
rc = wait_for_reset_state(ena_dev, timeout, 0);
- if (rc != 0) {
+ if (unlikely(rc)) {
ena_trc_err(ena_dev, "Reset indication didn't turn off\n");
return rc;
}
@@ -3383,7 +3383,7 @@ int ena_com_config_dev_mode(struct ena_com_dev *ena_dev,
}
rc = ena_com_config_llq_info(ena_dev, llq_features, llq_default_cfg);
- if (rc)
+ if (unlikely(rc))
return rc;
ena_dev->tx_max_header_size = llq_info->desc_list_entry_size -
diff --git a/drivers/net/ena/base/ena_eth_com.c
b/drivers/net/ena/base/ena_eth_com.c
index 58d1cc68d9..f672df1001 100644
--- a/drivers/net/ena/base/ena_eth_com.c
+++ b/drivers/net/ena/base/ena_eth_com.c
@@ -454,7 +454,7 @@ int ena_com_prepare_tx(struct ena_com_io_sq *io_sq,
/* If the caller doesn't want to send packets */
if (unlikely(!num_bufs && !header_len)) {
rc = ena_com_close_bounce_buffer(io_sq);
- if (rc)
+ if (unlikely(rc))
ena_trc_err(ena_com_io_sq_to_ena_dev(io_sq),
"Failed to write buffers to LLQ\n");
*nb_hw_desc = io_sq->tail - start_tail;
--
2.17.1
