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| author | Furong Xu <0x1207@gmail.com> | 2025-01-15 11:27:03 +0800 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2025-01-16 12:14:22 +0100 |
| commit | 2324c78a75c54b4c49d22bb44fcccf5727ba5ef7 (patch) | |
| tree | 84c2ca313b5a0c90d0f36a438d528062c9ed0242 /drivers/net/ethernet | |
| parent | df542f669307918f054a17878ff6dd1ddbb2fe18 (diff) | |
| download | linux-2324c78a75c54b4c49d22bb44fcccf5727ba5ef7.tar.gz linux-2324c78a75c54b4c49d22bb44fcccf5727ba5ef7.tar.bz2 linux-2324c78a75c54b4c49d22bb44fcccf5727ba5ef7.zip | |
net: stmmac: Set page_pool_params.max_len to a precise size
DMA engine will always write no more than dma_buf_sz bytes of a received
frame into a page buffer, the remaining spaces are unused or used by CPU
exclusively.
Setting page_pool_params.max_len to almost the full size of page(s) helps
nothing more, but wastes more CPU cycles on cache maintenance.
For a standard MTU of 1500, then dma_buf_sz is assigned to 1536, and this
patch brings ~16.9% driver performance improvement in a TCP RX
throughput test with iPerf tool on a single isolated Cortex-A65 CPU
core, from 2.43 Gbits/sec increased to 2.84 Gbits/sec.
Signed-off-by: Furong Xu <0x1207@gmail.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Yanteng Si <si.yanteng@linux.dev>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'drivers/net/ethernet')
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/stmmac_xdp.h | 1 |
2 files changed, 1 insertions, 2 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 1d98a5e8c98c..811e2d372abf 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -2059,7 +2059,7 @@ static int __alloc_dma_rx_desc_resources(struct stmmac_priv *priv, pp_params.dev = priv->device; pp_params.dma_dir = xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE; pp_params.offset = stmmac_rx_offset(priv); - pp_params.max_len = STMMAC_MAX_RX_BUF_SIZE(num_pages); + pp_params.max_len = dma_conf->dma_buf_sz; rx_q->page_pool = page_pool_create(&pp_params); if (IS_ERR(rx_q->page_pool)) { diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_xdp.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_xdp.h index 896dc987d4ef..77ce8cfbe976 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_xdp.h +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_xdp.h @@ -4,7 +4,6 @@ #ifndef _STMMAC_XDP_H_ #define _STMMAC_XDP_H_ -#define STMMAC_MAX_RX_BUF_SIZE(num) (((num) * PAGE_SIZE) - XDP_PACKET_HEADROOM) #define STMMAC_RX_DMA_ATTR (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING) int stmmac_xdp_setup_pool(struct stmmac_priv *priv, struct xsk_buff_pool *pool, |