From: "Björn Töpel" <bjorn.topel@gmail.com> To: ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, bpf@vger.kernel.org Cc: "Björn Töpel" <bjorn.topel@intel.com>, magnus.karlsson@intel.com, davem@davemloft.net, kuba@kernel.org, hawk@kernel.org, john.fastabend@gmail.com, intel-wired-lan@lists.osuosl.org Subject: [PATCH bpf-next 5/6] ice, xsk: finish napi loop if AF_XDP Rx queue is full Date: Fri, 4 Sep 2020 15:53:30 +0200 [thread overview] Message-ID: <20200904135332.60259-6-bjorn.topel@gmail.com> (raw) In-Reply-To: <20200904135332.60259-1-bjorn.topel@gmail.com> From: Björn Töpel <bjorn.topel@intel.com> Make the AF_XDP zero-copy path aware that the reason for redirect failure was due to full Rx queue. If so, exit the napi loop as soon as possible (exit the softirq processing), so that the userspace AF_XDP process can hopefully empty the Rx queue. This mainly helps the "one core scenario", where the userland process and Rx softirq processing is on the same core. Note that the early exit can only be performed if the "need wakeup" feature is enabled, because otherwise there is no notification mechanism available from the kernel side. This requires that the driver starts using the newly introduced xdp_do_redirect_ext() and xsk_do_redirect_rx_full() functions. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> --- drivers/net/ethernet/intel/ice/ice_xsk.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c index 797886524054..f698d0199b0a 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.c +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c @@ -502,13 +502,15 @@ ice_construct_skb_zc(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf) * ice_run_xdp_zc - Executes an XDP program in zero-copy path * @rx_ring: Rx ring * @xdp: xdp_buff used as input to the XDP program + * @early_exit: true means that the napi loop should exit early * * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR} */ static int -ice_run_xdp_zc(struct ice_ring *rx_ring, struct xdp_buff *xdp) +ice_run_xdp_zc(struct ice_ring *rx_ring, struct xdp_buff *xdp, bool *early_exit) { int err, result = ICE_XDP_PASS; + enum bpf_map_type map_type; struct bpf_prog *xdp_prog; struct ice_ring *xdp_ring; u32 act; @@ -529,8 +531,13 @@ ice_run_xdp_zc(struct ice_ring *rx_ring, struct xdp_buff *xdp) result = ice_xmit_xdp_buff(xdp, xdp_ring); break; case XDP_REDIRECT: - err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog); - result = !err ? ICE_XDP_REDIR : ICE_XDP_CONSUMED; + err = xdp_do_redirect_ext(rx_ring->netdev, xdp, xdp_prog, &map_type); + if (err) { + *early_exit = xsk_do_redirect_rx_full(err, map_type); + result = ICE_XDP_CONSUMED; + } else { + result = ICE_XDP_REDIR; + } break; default: bpf_warn_invalid_xdp_action(act); @@ -558,8 +565,8 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) { unsigned int total_rx_bytes = 0, total_rx_packets = 0; u16 cleaned_count = ICE_DESC_UNUSED(rx_ring); + bool early_exit = false, failure = false; unsigned int xdp_xmit = 0; - bool failure = false; while (likely(total_rx_packets < (unsigned int)budget)) { union ice_32b_rx_flex_desc *rx_desc; @@ -597,7 +604,7 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) rx_buf->xdp->data_end = rx_buf->xdp->data + size; xsk_buff_dma_sync_for_cpu(rx_buf->xdp, rx_ring->xsk_pool); - xdp_res = ice_run_xdp_zc(rx_ring, rx_buf->xdp); + xdp_res = ice_run_xdp_zc(rx_ring, rx_buf->xdp, &early_exit); if (xdp_res) { if (xdp_res & (ICE_XDP_TX | ICE_XDP_REDIR)) xdp_xmit |= xdp_res; @@ -610,6 +617,8 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) cleaned_count++; ice_bump_ntc(rx_ring); + if (early_exit) + break; continue; } @@ -646,12 +655,12 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) ice_update_rx_ring_stats(rx_ring, total_rx_packets, total_rx_bytes); if (xsk_uses_need_wakeup(rx_ring->xsk_pool)) { - if (failure || rx_ring->next_to_clean == rx_ring->next_to_use) + if (early_exit || failure || rx_ring->next_to_clean == rx_ring->next_to_use) xsk_set_rx_need_wakeup(rx_ring->xsk_pool); else xsk_clear_rx_need_wakeup(rx_ring->xsk_pool); - return (int)total_rx_packets; + return early_exit ? 0 : (int)total_rx_packets; } return failure ? budget : (int)total_rx_packets; -- 2.25.1
WARNING: multiple messages have this Message-ID (diff)
From: =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= <bjorn.topel@gmail.com> To: intel-wired-lan@osuosl.org Subject: [Intel-wired-lan] [PATCH bpf-next 5/6] ice, xsk: finish napi loop if AF_XDP Rx queue is full Date: Fri, 4 Sep 2020 15:53:30 +0200 [thread overview] Message-ID: <20200904135332.60259-6-bjorn.topel@gmail.com> (raw) In-Reply-To: <20200904135332.60259-1-bjorn.topel@gmail.com> From: Bj?rn T?pel <bjorn.topel@intel.com> Make the AF_XDP zero-copy path aware that the reason for redirect failure was due to full Rx queue. If so, exit the napi loop as soon as possible (exit the softirq processing), so that the userspace AF_XDP process can hopefully empty the Rx queue. This mainly helps the "one core scenario", where the userland process and Rx softirq processing is on the same core. Note that the early exit can only be performed if the "need wakeup" feature is enabled, because otherwise there is no notification mechanism available from the kernel side. This requires that the driver starts using the newly introduced xdp_do_redirect_ext() and xsk_do_redirect_rx_full() functions. Signed-off-by: Bj?rn T?pel <bjorn.topel@intel.com> --- drivers/net/ethernet/intel/ice/ice_xsk.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c index 797886524054..f698d0199b0a 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.c +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c @@ -502,13 +502,15 @@ ice_construct_skb_zc(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf) * ice_run_xdp_zc - Executes an XDP program in zero-copy path * @rx_ring: Rx ring * @xdp: xdp_buff used as input to the XDP program + * @early_exit: true means that the napi loop should exit early * * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR} */ static int -ice_run_xdp_zc(struct ice_ring *rx_ring, struct xdp_buff *xdp) +ice_run_xdp_zc(struct ice_ring *rx_ring, struct xdp_buff *xdp, bool *early_exit) { int err, result = ICE_XDP_PASS; + enum bpf_map_type map_type; struct bpf_prog *xdp_prog; struct ice_ring *xdp_ring; u32 act; @@ -529,8 +531,13 @@ ice_run_xdp_zc(struct ice_ring *rx_ring, struct xdp_buff *xdp) result = ice_xmit_xdp_buff(xdp, xdp_ring); break; case XDP_REDIRECT: - err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog); - result = !err ? ICE_XDP_REDIR : ICE_XDP_CONSUMED; + err = xdp_do_redirect_ext(rx_ring->netdev, xdp, xdp_prog, &map_type); + if (err) { + *early_exit = xsk_do_redirect_rx_full(err, map_type); + result = ICE_XDP_CONSUMED; + } else { + result = ICE_XDP_REDIR; + } break; default: bpf_warn_invalid_xdp_action(act); @@ -558,8 +565,8 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) { unsigned int total_rx_bytes = 0, total_rx_packets = 0; u16 cleaned_count = ICE_DESC_UNUSED(rx_ring); + bool early_exit = false, failure = false; unsigned int xdp_xmit = 0; - bool failure = false; while (likely(total_rx_packets < (unsigned int)budget)) { union ice_32b_rx_flex_desc *rx_desc; @@ -597,7 +604,7 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) rx_buf->xdp->data_end = rx_buf->xdp->data + size; xsk_buff_dma_sync_for_cpu(rx_buf->xdp, rx_ring->xsk_pool); - xdp_res = ice_run_xdp_zc(rx_ring, rx_buf->xdp); + xdp_res = ice_run_xdp_zc(rx_ring, rx_buf->xdp, &early_exit); if (xdp_res) { if (xdp_res & (ICE_XDP_TX | ICE_XDP_REDIR)) xdp_xmit |= xdp_res; @@ -610,6 +617,8 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) cleaned_count++; ice_bump_ntc(rx_ring); + if (early_exit) + break; continue; } @@ -646,12 +655,12 @@ int ice_clean_rx_irq_zc(struct ice_ring *rx_ring, int budget) ice_update_rx_ring_stats(rx_ring, total_rx_packets, total_rx_bytes); if (xsk_uses_need_wakeup(rx_ring->xsk_pool)) { - if (failure || rx_ring->next_to_clean == rx_ring->next_to_use) + if (early_exit || failure || rx_ring->next_to_clean == rx_ring->next_to_use) xsk_set_rx_need_wakeup(rx_ring->xsk_pool); else xsk_clear_rx_need_wakeup(rx_ring->xsk_pool); - return (int)total_rx_packets; + return early_exit ? 0 : (int)total_rx_packets; } return failure ? budget : (int)total_rx_packets; -- 2.25.1
next prev parent reply other threads:[~2020-09-04 13:54 UTC|newest] Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-09-04 13:53 [PATCH bpf-next 0/6] xsk: exit NAPI loop when AF_XDP Rx ring is full Björn Töpel 2020-09-04 13:53 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 13:53 ` [PATCH bpf-next 1/6] xsk: improve xdp_do_redirect() error codes Björn Töpel 2020-09-04 13:53 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 13:53 ` [PATCH bpf-next 2/6] xdp: introduce xdp_do_redirect_ext() function Björn Töpel 2020-09-04 13:53 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 13:53 ` [PATCH bpf-next 3/6] xsk: introduce xsk_do_redirect_rx_full() helper Björn Töpel 2020-09-04 13:53 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 15:11 ` Jesper Dangaard Brouer 2020-09-04 15:11 ` [Intel-wired-lan] " Jesper Dangaard Brouer 2020-09-04 15:39 ` Björn Töpel 2020-09-04 15:39 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-07 12:45 ` Jesper Dangaard Brouer 2020-09-07 12:45 ` [Intel-wired-lan] " Jesper Dangaard Brouer 2020-09-04 13:53 ` [PATCH bpf-next 4/6] i40e, xsk: finish napi loop if AF_XDP Rx queue is full Björn Töpel 2020-09-04 13:53 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 13:53 ` Björn Töpel [this message] 2020-09-04 13:53 ` [Intel-wired-lan] [PATCH bpf-next 5/6] ice, " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 13:53 ` [PATCH bpf-next 6/6] ixgbe, " Björn Töpel 2020-09-04 13:53 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 15:35 ` Jesper Dangaard Brouer 2020-09-04 15:35 ` [Intel-wired-lan] " Jesper Dangaard Brouer 2020-09-04 15:54 ` Björn Töpel 2020-09-04 15:54 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 13:59 ` [PATCH bpf-next 0/6] xsk: exit NAPI loop when AF_XDP Rx ring " Björn Töpel 2020-09-04 13:59 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-08 10:32 ` Maxim Mikityanskiy 2020-09-08 10:32 ` [Intel-wired-lan] " Maxim Mikityanskiy 2020-09-08 11:37 ` Magnus Karlsson 2020-09-08 11:37 ` [Intel-wired-lan] " Magnus Karlsson 2020-09-08 12:21 ` Björn Töpel 2020-09-08 12:21 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-09 15:37 ` Jesper Dangaard Brouer 2020-09-09 15:37 ` [Intel-wired-lan] " Jesper Dangaard Brouer 2020-09-04 14:27 ` Jesper Dangaard Brouer 2020-09-04 14:27 ` [Intel-wired-lan] " Jesper Dangaard Brouer 2020-09-04 14:32 ` Björn Töpel 2020-09-04 14:32 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-04 23:58 ` Jakub Kicinski 2020-09-04 23:58 ` [Intel-wired-lan] " Jakub Kicinski 2020-09-07 13:37 ` Björn Töpel 2020-09-07 13:37 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-07 18:40 ` Jakub Kicinski 2020-09-07 18:40 ` [Intel-wired-lan] " Jakub Kicinski 2020-09-08 6:58 ` Björn Töpel 2020-09-08 6:58 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-08 17:24 ` Jakub Kicinski 2020-09-08 17:24 ` [Intel-wired-lan] " Jakub Kicinski 2020-09-08 18:28 ` Björn Töpel 2020-09-08 18:28 ` [Intel-wired-lan] " =?unknown-8bit?q?Bj=C3=B6rn_T=C3=B6pel?= 2020-09-08 18:34 ` Jakub Kicinski 2020-09-08 18:34 ` [Intel-wired-lan] " Jakub Kicinski
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20200904135332.60259-6-bjorn.topel@gmail.com \ --to=bjorn.topel@gmail.com \ --cc=ast@kernel.org \ --cc=bjorn.topel@intel.com \ --cc=bpf@vger.kernel.org \ --cc=daniel@iogearbox.net \ --cc=davem@davemloft.net \ --cc=hawk@kernel.org \ --cc=intel-wired-lan@lists.osuosl.org \ --cc=john.fastabend@gmail.com \ --cc=kuba@kernel.org \ --cc=magnus.karlsson@intel.com \ --cc=netdev@vger.kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.