* [PATCH net-next] net: mvneta: try to use in-irq pp cache in mvneta_txq_bufs_free @ 2020-09-25 10:01 Lorenzo Bianconi 2020-09-25 10:52 ` Jesper Dangaard Brouer 0 siblings, 1 reply; 5+ messages in thread From: Lorenzo Bianconi @ 2020-09-25 10:01 UTC (permalink / raw) To: netdev; +Cc: davem, kuba, lorenzo.bianconi, brouer, echaudro, thomas.petazzoni Try to recycle the xdp tx buffer into the in-irq page_pool cache if mvneta_txq_bufs_free is executed in the NAPI context. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- drivers/net/ethernet/marvell/mvneta.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 14df3aec285d..646fbf4ed638 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -1831,7 +1831,7 @@ static struct mvneta_tx_queue *mvneta_tx_done_policy(struct mvneta_port *pp, /* Free tx queue skbuffs */ static void mvneta_txq_bufs_free(struct mvneta_port *pp, struct mvneta_tx_queue *txq, int num, - struct netdev_queue *nq) + struct netdev_queue *nq, bool napi) { unsigned int bytes_compl = 0, pkts_compl = 0; int i; @@ -1854,7 +1854,10 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp, dev_kfree_skb_any(buf->skb); } else if (buf->type == MVNETA_TYPE_XDP_TX || buf->type == MVNETA_TYPE_XDP_NDO) { - xdp_return_frame(buf->xdpf); + if (napi) + xdp_return_frame_rx_napi(buf->xdpf); + else + xdp_return_frame(buf->xdpf); } } @@ -1872,7 +1875,7 @@ static void mvneta_txq_done(struct mvneta_port *pp, if (!tx_done) return; - mvneta_txq_bufs_free(pp, txq, tx_done, nq); + mvneta_txq_bufs_free(pp, txq, tx_done, nq, true); txq->count -= tx_done; @@ -2859,7 +2862,7 @@ static void mvneta_txq_done_force(struct mvneta_port *pp, struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id); int tx_done = txq->count; - mvneta_txq_bufs_free(pp, txq, tx_done, nq); + mvneta_txq_bufs_free(pp, txq, tx_done, nq, false); /* reset txq */ txq->count = 0; -- 2.26.2 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH net-next] net: mvneta: try to use in-irq pp cache in mvneta_txq_bufs_free 2020-09-25 10:01 [PATCH net-next] net: mvneta: try to use in-irq pp cache in mvneta_txq_bufs_free Lorenzo Bianconi @ 2020-09-25 10:52 ` Jesper Dangaard Brouer 2020-09-25 11:29 ` Lorenzo Bianconi 0 siblings, 1 reply; 5+ messages in thread From: Jesper Dangaard Brouer @ 2020-09-25 10:52 UTC (permalink / raw) To: Lorenzo Bianconi Cc: netdev, davem, kuba, lorenzo.bianconi, echaudro, thomas.petazzoni, brouer On Fri, 25 Sep 2020 12:01:32 +0200 Lorenzo Bianconi <lorenzo@kernel.org> wrote: > Try to recycle the xdp tx buffer into the in-irq page_pool cache if > mvneta_txq_bufs_free is executed in the NAPI context. NACK - I don't think this is safe. That is also why I named the function postfix rx_napi. The page pool->alloc.cache is associated with the drivers RX-queue. The xdp_frame's that gets freed could be coming from a remote driver that use page_pool. This remote drivers RX-queue processing can run concurrently on a different CPU, than this drivers TXQ-cleanup. If you want to speedup this, I instead suggest that you add a xdp_return_frame_bulk API. > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > --- > drivers/net/ethernet/marvell/mvneta.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > index 14df3aec285d..646fbf4ed638 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -1831,7 +1831,7 @@ static struct mvneta_tx_queue *mvneta_tx_done_policy(struct mvneta_port *pp, > /* Free tx queue skbuffs */ > static void mvneta_txq_bufs_free(struct mvneta_port *pp, > struct mvneta_tx_queue *txq, int num, > - struct netdev_queue *nq) > + struct netdev_queue *nq, bool napi) > { > unsigned int bytes_compl = 0, pkts_compl = 0; > int i; > @@ -1854,7 +1854,10 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp, > dev_kfree_skb_any(buf->skb); > } else if (buf->type == MVNETA_TYPE_XDP_TX || > buf->type == MVNETA_TYPE_XDP_NDO) { > - xdp_return_frame(buf->xdpf); > + if (napi) > + xdp_return_frame_rx_napi(buf->xdpf); > + else > + xdp_return_frame(buf->xdpf); > } > } > > @@ -1872,7 +1875,7 @@ static void mvneta_txq_done(struct mvneta_port *pp, > if (!tx_done) > return; > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, true); > > txq->count -= tx_done; > > @@ -2859,7 +2862,7 @@ static void mvneta_txq_done_force(struct mvneta_port *pp, > struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id); > int tx_done = txq->count; > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, false); > > /* reset txq */ > txq->count = 0; -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH net-next] net: mvneta: try to use in-irq pp cache in mvneta_txq_bufs_free 2020-09-25 10:52 ` Jesper Dangaard Brouer @ 2020-09-25 11:29 ` Lorenzo Bianconi 2020-09-25 12:09 ` Jesper Dangaard Brouer 0 siblings, 1 reply; 5+ messages in thread From: Lorenzo Bianconi @ 2020-09-25 11:29 UTC (permalink / raw) To: Jesper Dangaard Brouer Cc: Lorenzo Bianconi, Network Development, David S. Miller, Jakub Kicinski, Eelco Chaudron, thomas.petazzoni > > On Fri, 25 Sep 2020 12:01:32 +0200 > Lorenzo Bianconi <lorenzo@kernel.org> wrote: > > > Try to recycle the xdp tx buffer into the in-irq page_pool cache if > > mvneta_txq_bufs_free is executed in the NAPI context. > > NACK - I don't think this is safe. That is also why I named the > function postfix rx_napi. The page pool->alloc.cache is associated > with the drivers RX-queue. The xdp_frame's that gets freed could be > coming from a remote driver that use page_pool. This remote drivers > RX-queue processing can run concurrently on a different CPU, than this > drivers TXQ-cleanup. ack, right. What about if we do it just XDP_TX use case? Like: if (napi && buf->type == MVNETA_TYPE_XDP_TX) xdp_return_frame_rx_napi(buf->xdpf); else xdp_return_frame(buf->xdpf); In this way we are sure the packet is coming from local page_pool. > > If you want to speedup this, I instead suggest that you add a > xdp_return_frame_bulk API. I will look at it Regards, Lorenzo > > > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > > --- > > drivers/net/ethernet/marvell/mvneta.c | 11 +++++++---- > > 1 file changed, 7 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > > index 14df3aec285d..646fbf4ed638 100644 > > --- a/drivers/net/ethernet/marvell/mvneta.c > > +++ b/drivers/net/ethernet/marvell/mvneta.c > > @@ -1831,7 +1831,7 @@ static struct mvneta_tx_queue *mvneta_tx_done_policy(struct mvneta_port *pp, > > /* Free tx queue skbuffs */ > > static void mvneta_txq_bufs_free(struct mvneta_port *pp, > > struct mvneta_tx_queue *txq, int num, > > - struct netdev_queue *nq) > > + struct netdev_queue *nq, bool napi) > > { > > unsigned int bytes_compl = 0, pkts_compl = 0; > > int i; > > @@ -1854,7 +1854,10 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp, > > dev_kfree_skb_any(buf->skb); > > } else if (buf->type == MVNETA_TYPE_XDP_TX || > > buf->type == MVNETA_TYPE_XDP_NDO) { > > - xdp_return_frame(buf->xdpf); > > + if (napi) > > + xdp_return_frame_rx_napi(buf->xdpf); > > + else > > + xdp_return_frame(buf->xdpf); > > } > > } > > > > @@ -1872,7 +1875,7 @@ static void mvneta_txq_done(struct mvneta_port *pp, > > if (!tx_done) > > return; > > > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, true); > > > > txq->count -= tx_done; > > > > @@ -2859,7 +2862,7 @@ static void mvneta_txq_done_force(struct mvneta_port *pp, > > struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id); > > int tx_done = txq->count; > > > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, false); > > > > /* reset txq */ > > txq->count = 0; > > > > -- > Best regards, > Jesper Dangaard Brouer > MSc.CS, Principal Kernel Engineer at Red Hat > LinkedIn: http://www.linkedin.com/in/brouer > ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH net-next] net: mvneta: try to use in-irq pp cache in mvneta_txq_bufs_free 2020-09-25 11:29 ` Lorenzo Bianconi @ 2020-09-25 12:09 ` Jesper Dangaard Brouer 2020-09-25 13:05 ` Lorenzo Bianconi 0 siblings, 1 reply; 5+ messages in thread From: Jesper Dangaard Brouer @ 2020-09-25 12:09 UTC (permalink / raw) To: Lorenzo Bianconi Cc: Lorenzo Bianconi, Network Development, David S. Miller, Jakub Kicinski, Eelco Chaudron, thomas.petazzoni, brouer On Fri, 25 Sep 2020 13:29:00 +0200 Lorenzo Bianconi <lorenzo.bianconi@redhat.com> wrote: > > > > On Fri, 25 Sep 2020 12:01:32 +0200 > > Lorenzo Bianconi <lorenzo@kernel.org> wrote: > > > > > Try to recycle the xdp tx buffer into the in-irq page_pool cache if > > > mvneta_txq_bufs_free is executed in the NAPI context. > > > > NACK - I don't think this is safe. That is also why I named the > > function postfix rx_napi. The page pool->alloc.cache is associated > > with the drivers RX-queue. The xdp_frame's that gets freed could be > > coming from a remote driver that use page_pool. This remote drivers > > RX-queue processing can run concurrently on a different CPU, than this > > drivers TXQ-cleanup. > > ack, right. What about if we do it just XDP_TX use case? Like: > > if (napi && buf->type == MVNETA_TYPE_XDP_TX) > xdp_return_frame_rx_napi(buf->xdpf); > else > xdp_return_frame(buf->xdpf); > > In this way we are sure the packet is coming from local page_pool. Yes, that case XDP_TX should be safe. > > > > If you want to speedup this, I instead suggest that you add a > > xdp_return_frame_bulk API. > > I will look at it Great! Notice that bulk return should be easy/obvious in most drivers, as they (like mvneta in mvneta_txq_bufs_free()) have a loop that process several TXQ completions. I did a quick tests on mlx5 with xdp_redirect_map and perf report shows __xdp_return calls at the top#1 overhead. # Overhead CPU Symbol # ........ ... .................................... # 8.46% 003 [k] __xdp_return 6.41% 003 [k] dma_direct_map_page 4.65% 003 [k] bpf_xdp_redirect_map 4.58% 003 [k] dma_direct_unmap_page 4.04% 003 [k] xdp_do_redirect 3.53% 003 [k] __page_pool_put_page 3.27% 003 [k] dma_direct_sync_single_for_cpu 2.63% 003 [k] dev_map_enqueue 2.28% 003 [k] page_pool_refill_alloc_cache 1.69% 003 [k] bq_enqueue.isra.0 1.15% 003 [k] _raw_spin_lock 0.92% 003 [k] xdp_return_frame Thus, there will be a benefit from implementing a bulk return. Also for your XDP_TX case, as the overhead in __xdp_return also exist for rx_napi variant. > > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > > > --- > > > drivers/net/ethernet/marvell/mvneta.c | 11 +++++++---- > > > 1 file changed, 7 insertions(+), 4 deletions(-) > > > > > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > > > index 14df3aec285d..646fbf4ed638 100644 > > > --- a/drivers/net/ethernet/marvell/mvneta.c > > > +++ b/drivers/net/ethernet/marvell/mvneta.c > > > @@ -1831,7 +1831,7 @@ static struct mvneta_tx_queue *mvneta_tx_done_policy(struct mvneta_port *pp, > > > /* Free tx queue skbuffs */ > > > static void mvneta_txq_bufs_free(struct mvneta_port *pp, > > > struct mvneta_tx_queue *txq, int num, > > > - struct netdev_queue *nq) > > > + struct netdev_queue *nq, bool napi) > > > { > > > unsigned int bytes_compl = 0, pkts_compl = 0; > > > int i; > > > @@ -1854,7 +1854,10 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp, > > > dev_kfree_skb_any(buf->skb); > > > } else if (buf->type == MVNETA_TYPE_XDP_TX || > > > buf->type == MVNETA_TYPE_XDP_NDO) { > > > - xdp_return_frame(buf->xdpf); > > > + if (napi) > > > + xdp_return_frame_rx_napi(buf->xdpf); > > > + else > > > + xdp_return_frame(buf->xdpf); > > > } > > > } > > > > > > @@ -1872,7 +1875,7 @@ static void mvneta_txq_done(struct mvneta_port *pp, > > > if (!tx_done) > > > return; > > > > > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > > > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, true); > > > > > > txq->count -= tx_done; > > > > > > @@ -2859,7 +2862,7 @@ static void mvneta_txq_done_force(struct mvneta_port *pp, > > > struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id); > > > int tx_done = txq->count; > > > > > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > > > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, false); > > > > > > /* reset txq */ > > > txq->count = 0; -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH net-next] net: mvneta: try to use in-irq pp cache in mvneta_txq_bufs_free 2020-09-25 12:09 ` Jesper Dangaard Brouer @ 2020-09-25 13:05 ` Lorenzo Bianconi 0 siblings, 0 replies; 5+ messages in thread From: Lorenzo Bianconi @ 2020-09-25 13:05 UTC (permalink / raw) To: Jesper Dangaard Brouer Cc: Lorenzo Bianconi, Network Development, David S. Miller, Jakub Kicinski, Eelco Chaudron, thomas.petazzoni [-- Attachment #1: Type: text/plain, Size: 5235 bytes --] > On Fri, 25 Sep 2020 13:29:00 +0200 > Lorenzo Bianconi <lorenzo.bianconi@redhat.com> wrote: > > > > > > > On Fri, 25 Sep 2020 12:01:32 +0200 > > > Lorenzo Bianconi <lorenzo@kernel.org> wrote: > > > > > > > Try to recycle the xdp tx buffer into the in-irq page_pool cache if > > > > mvneta_txq_bufs_free is executed in the NAPI context. > > > > > > NACK - I don't think this is safe. That is also why I named the > > > function postfix rx_napi. The page pool->alloc.cache is associated > > > with the drivers RX-queue. The xdp_frame's that gets freed could be > > > coming from a remote driver that use page_pool. This remote drivers > > > RX-queue processing can run concurrently on a different CPU, than this > > > drivers TXQ-cleanup. > > > > ack, right. What about if we do it just XDP_TX use case? Like: > > > > if (napi && buf->type == MVNETA_TYPE_XDP_TX) > > xdp_return_frame_rx_napi(buf->xdpf); > > else > > xdp_return_frame(buf->xdpf); > > > > In this way we are sure the packet is coming from local page_pool. > > Yes, that case XDP_TX should be safe. > > > > > > > If you want to speedup this, I instead suggest that you add a > > > xdp_return_frame_bulk API. > > > > I will look at it > > Great! > > Notice that bulk return should be easy/obvious in most drivers, as they > (like mvneta in mvneta_txq_bufs_free()) have a loop that process > several TXQ completions. > > I did a quick tests on mlx5 with xdp_redirect_map and perf report shows > __xdp_return calls at the top#1 overhead. > > # Overhead CPU Symbol > # ........ ... .................................... > # > 8.46% 003 [k] __xdp_return > 6.41% 003 [k] dma_direct_map_page > 4.65% 003 [k] bpf_xdp_redirect_map > 4.58% 003 [k] dma_direct_unmap_page > 4.04% 003 [k] xdp_do_redirect > 3.53% 003 [k] __page_pool_put_page > 3.27% 003 [k] dma_direct_sync_single_for_cpu > 2.63% 003 [k] dev_map_enqueue > 2.28% 003 [k] page_pool_refill_alloc_cache > 1.69% 003 [k] bq_enqueue.isra.0 > 1.15% 003 [k] _raw_spin_lock > 0.92% 003 [k] xdp_return_frame > > Thus, there will be a benefit from implementing a bulk return. Also > for your XDP_TX case, as the overhead in __xdp_return also exist for > rx_napi variant. ack, I will post a v2 limiting the xdp_return_frame_rx_napi just for XDP_TX use-case and then I will look at implementing a xdp bulk return. Regards, Lorenzo > > > > > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > > > > --- > > > > drivers/net/ethernet/marvell/mvneta.c | 11 +++++++---- > > > > 1 file changed, 7 insertions(+), 4 deletions(-) > > > > > > > > diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c > > > > index 14df3aec285d..646fbf4ed638 100644 > > > > --- a/drivers/net/ethernet/marvell/mvneta.c > > > > +++ b/drivers/net/ethernet/marvell/mvneta.c > > > > @@ -1831,7 +1831,7 @@ static struct mvneta_tx_queue *mvneta_tx_done_policy(struct mvneta_port *pp, > > > > /* Free tx queue skbuffs */ > > > > static void mvneta_txq_bufs_free(struct mvneta_port *pp, > > > > struct mvneta_tx_queue *txq, int num, > > > > - struct netdev_queue *nq) > > > > + struct netdev_queue *nq, bool napi) > > > > { > > > > unsigned int bytes_compl = 0, pkts_compl = 0; > > > > int i; > > > > @@ -1854,7 +1854,10 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp, > > > > dev_kfree_skb_any(buf->skb); > > > > } else if (buf->type == MVNETA_TYPE_XDP_TX || > > > > buf->type == MVNETA_TYPE_XDP_NDO) { > > > > - xdp_return_frame(buf->xdpf); > > > > + if (napi) > > > > + xdp_return_frame_rx_napi(buf->xdpf); > > > > + else > > > > + xdp_return_frame(buf->xdpf); > > > > } > > > > } > > > > > > > > @@ -1872,7 +1875,7 @@ static void mvneta_txq_done(struct mvneta_port *pp, > > > > if (!tx_done) > > > > return; > > > > > > > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > > > > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, true); > > > > > > > > txq->count -= tx_done; > > > > > > > > @@ -2859,7 +2862,7 @@ static void mvneta_txq_done_force(struct mvneta_port *pp, > > > > struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id); > > > > int tx_done = txq->count; > > > > > > > > - mvneta_txq_bufs_free(pp, txq, tx_done, nq); > > > > + mvneta_txq_bufs_free(pp, txq, tx_done, nq, false); > > > > > > > > /* reset txq */ > > > > txq->count = 0; > > -- > Best regards, > Jesper Dangaard Brouer > MSc.CS, Principal Kernel Engineer at Red Hat > LinkedIn: http://www.linkedin.com/in/brouer > [-- Attachment #2: signature.asc --] [-- Type: application/pgp-signature, Size: 228 bytes --] ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2020-09-25 13:05 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-09-25 10:01 [PATCH net-next] net: mvneta: try to use in-irq pp cache in mvneta_txq_bufs_free Lorenzo Bianconi 2020-09-25 10:52 ` Jesper Dangaard Brouer 2020-09-25 11:29 ` Lorenzo Bianconi 2020-09-25 12:09 ` Jesper Dangaard Brouer 2020-09-25 13:05 ` Lorenzo Bianconi
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