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| author | Lorenzo Bianconi <lorenzo@kernel.org> | 2020-09-29 23:58:57 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-09-29 18:10:07 -0700 |
| commit | 879456bedbe54f2d38b15c21dc5e3c30232b53e1 (patch) | |
| tree | 1c39b06c8314cb7b6d89d00b0f33acaa22c3f861 /drivers | |
| parent | 2b2706aaaefee49ba0030bc679865db178e89e11 (diff) | |
| download | lwn-879456bedbe54f2d38b15c21dc5e3c30232b53e1.tar.gz lwn-879456bedbe54f2d38b15c21dc5e3c30232b53e1.zip | |
net: mvneta: avoid possible cache misses in mvneta_rx_swbm
Do not use rx_desc pointers if possible since rx descriptors are stored in
uncached memory and dereferencing rx_desc pointers generate extra loads.
This patch improves XDP_DROP performance of ~ 110Kpps (700Kpps vs 590Kpps)
on Marvell Espressobin
Analyzed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/ethernet/marvell/mvneta.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index bb485745b72a..d095718355d3 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -2236,19 +2236,22 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp, enum dma_data_direction dma_dir; struct skb_shared_info *sinfo; - if (rx_desc->data_size > MVNETA_MAX_RX_BUF_SIZE) { + if (*size > MVNETA_MAX_RX_BUF_SIZE) { len = MVNETA_MAX_RX_BUF_SIZE; data_len += len; } else { - len = rx_desc->data_size; + len = *size; data_len += len - ETH_FCS_LEN; } + *size = *size - len; dma_dir = page_pool_get_dma_dir(rxq->page_pool); dma_sync_single_for_cpu(dev->dev.parent, rx_desc->buf_phys_addr, len, dma_dir); + rx_desc->buf_phys_addr = 0; + /* Prefetch header */ prefetch(data); @@ -2259,9 +2262,6 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp, sinfo = xdp_get_shared_info_from_buff(xdp); sinfo->nr_frags = 0; - - *size = rx_desc->data_size - len; - rx_desc->buf_phys_addr = 0; } static void @@ -2375,7 +2375,7 @@ static int mvneta_rx_swbm(struct napi_struct *napi, size = rx_desc->data_size; frame_sz = size - ETH_FCS_LEN; - desc_status = rx_desc->status; + desc_status = rx_status; mvneta_swbm_rx_frame(pp, rx_desc, rxq, &xdp_buf, &size, page); |