| Message ID | 1472896767-18352-3-git-send-email-sean.wang@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 03/09/2016 11:59, sean.wang@mediatek.com wrote: > From: Sean Wang <sean.wang@mediatek.com> > > The patch adds support for aggregating more SKBs feed into NAPI in > order to get more benefits from generic receive offload (GRO) by > peeking at the RX ring status and moving more packets right before > returning from NAPI RX polling handler if NAPI budgets are still > available and some packets already present in hardware. > > Signed-off-by: Sean Wang <sean.wang@mediatek.com> this looks ok to me, gave it a quick try on my HW and it works well. i am just not sure if this is something that is commonly done. someone with more overview of how NAPI should be used might want to comment on this. Tested-by: John Crispin <john@phrozen.org> > --- > drivers/net/ethernet/mediatek/mtk_eth_soc.c | 31 ++++++++++++++++------------- > 1 file changed, 17 insertions(+), 14 deletions(-) > > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > index a1bdb53..66fd45a 100644 > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > @@ -893,14 +893,14 @@ release_desc: > > done++; > } > - /* make sure that all changes to the dma ring are flushed before > - * we continue > - */ > - wmb(); > - mtk_w32(eth, ring->calc_idx, MTK_PRX_CRX_IDX0); > > - if (done < budget) > - mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_STATUS); > + if (done) { > + /* make sure that all changes to the dma ring are flushed before > + * we continue > + */ > + wmb(); > + mtk_w32(eth, ring->calc_idx, MTK_PRX_CRX_IDX0); > + } > > return done; > } > @@ -1020,10 +1020,13 @@ static int mtk_napi_rx(struct napi_struct *napi, int budget) > struct mtk_eth *eth = container_of(napi, struct mtk_eth, rx_napi); > u32 status, mask; > int rx_done = 0; > + int remain_budget = budget; > > mtk_handle_status_irq(eth); > + > +poll_again: > mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_STATUS); > - rx_done = mtk_poll_rx(napi, budget, eth); > + rx_done = mtk_poll_rx(napi, remain_budget, eth); > > if (unlikely(netif_msg_intr(eth))) { > status = mtk_r32(eth, MTK_PDMA_INT_STATUS); > @@ -1032,18 +1035,18 @@ static int mtk_napi_rx(struct napi_struct *napi, int budget) > "done rx %d, intr 0x%08x/0x%x\n", > rx_done, status, mask); > } > - > - if (rx_done == budget) > + if (rx_done == remain_budget) > return budget; > > status = mtk_r32(eth, MTK_PDMA_INT_STATUS); > - if (status & MTK_RX_DONE_INT) > - return budget; > - > + if (status & MTK_RX_DONE_INT) { > + remain_budget -= rx_done; > + goto poll_again; > + } > napi_complete(napi); > mtk_irq_enable(eth, MTK_PDMA_INT_MASK, MTK_RX_DONE_INT); > > - return rx_done; > + return rx_done + budget - remain_budget; > } > > static int mtk_tx_alloc(struct mtk_eth *eth) >
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index a1bdb53..66fd45a 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -893,14 +893,14 @@ release_desc: done++; } - /* make sure that all changes to the dma ring are flushed before - * we continue - */ - wmb(); - mtk_w32(eth, ring->calc_idx, MTK_PRX_CRX_IDX0); - if (done < budget) - mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_STATUS); + if (done) { + /* make sure that all changes to the dma ring are flushed before + * we continue + */ + wmb(); + mtk_w32(eth, ring->calc_idx, MTK_PRX_CRX_IDX0); + } return done; } @@ -1020,10 +1020,13 @@ static int mtk_napi_rx(struct napi_struct *napi, int budget) struct mtk_eth *eth = container_of(napi, struct mtk_eth, rx_napi); u32 status, mask; int rx_done = 0; + int remain_budget = budget; mtk_handle_status_irq(eth); + +poll_again: mtk_w32(eth, MTK_RX_DONE_INT, MTK_PDMA_INT_STATUS); - rx_done = mtk_poll_rx(napi, budget, eth); + rx_done = mtk_poll_rx(napi, remain_budget, eth); if (unlikely(netif_msg_intr(eth))) { status = mtk_r32(eth, MTK_PDMA_INT_STATUS); @@ -1032,18 +1035,18 @@ static int mtk_napi_rx(struct napi_struct *napi, int budget) "done rx %d, intr 0x%08x/0x%x\n", rx_done, status, mask); } - - if (rx_done == budget) + if (rx_done == remain_budget) return budget; status = mtk_r32(eth, MTK_PDMA_INT_STATUS); - if (status & MTK_RX_DONE_INT) - return budget; - + if (status & MTK_RX_DONE_INT) { + remain_budget -= rx_done; + goto poll_again; + } napi_complete(napi); mtk_irq_enable(eth, MTK_PDMA_INT_MASK, MTK_RX_DONE_INT); - return rx_done; + return rx_done + budget - remain_budget; } static int mtk_tx_alloc(struct mtk_eth *eth)