From 73a370795371e41f72aeca61656d47adeadf28e5 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 17 Jun 2009 21:17:59 +0000 Subject: forcedeth: fix dma api mismatches forcedeth doesnt use properly dma api in its tx completion path and in nv_loopback_test() pci_map_single() should be paired with pci_unmap_single() pci_map_page() should be paired with pci_unmap_page() forcedeth xmit path uses pci_map_single() & pci_map_page(), but tx completion path only uses pci_unmap_single() nv_loopback_test() uses pci_map_single() & pci_unmap_page() Add a dma_single field in struct nv_skb_map, and define a helper function nv_unmap_txskb Signed-off-by: Eric Dumazet CC: Ayaz Abdulla Signed-off-by: David S. Miller --- drivers/net/forcedeth.c | 46 +++++++++++++++++++++++++++------------------- 1 file changed, 27 insertions(+), 19 deletions(-) (limited to 'drivers/net/forcedeth.c') diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c index b60a3041b64..1094d292630 100644 --- a/drivers/net/forcedeth.c +++ b/drivers/net/forcedeth.c @@ -719,7 +719,8 @@ static const struct register_test nv_registers_test[] = { struct nv_skb_map { struct sk_buff *skb; dma_addr_t dma; - unsigned int dma_len; + unsigned int dma_len:31; + unsigned int dma_single:1; struct ring_desc_ex *first_tx_desc; struct nv_skb_map *next_tx_ctx; }; @@ -1912,6 +1913,7 @@ static void nv_init_tx(struct net_device *dev) np->tx_skb[i].skb = NULL; np->tx_skb[i].dma = 0; np->tx_skb[i].dma_len = 0; + np->tx_skb[i].dma_single = 0; np->tx_skb[i].first_tx_desc = NULL; np->tx_skb[i].next_tx_ctx = NULL; } @@ -1930,23 +1932,30 @@ static int nv_init_ring(struct net_device *dev) return nv_alloc_rx_optimized(dev); } -static int nv_release_txskb(struct net_device *dev, struct nv_skb_map* tx_skb) +static void nv_unmap_txskb(struct fe_priv *np, struct nv_skb_map *tx_skb) { - struct fe_priv *np = netdev_priv(dev); - if (tx_skb->dma) { - pci_unmap_page(np->pci_dev, tx_skb->dma, - tx_skb->dma_len, - PCI_DMA_TODEVICE); + if (tx_skb->dma_single) + pci_unmap_single(np->pci_dev, tx_skb->dma, + tx_skb->dma_len, + PCI_DMA_TODEVICE); + else + pci_unmap_page(np->pci_dev, tx_skb->dma, + tx_skb->dma_len, + PCI_DMA_TODEVICE); tx_skb->dma = 0; } +} + +static int nv_release_txskb(struct fe_priv *np, struct nv_skb_map *tx_skb) +{ + nv_unmap_txskb(np, tx_skb); if (tx_skb->skb) { dev_kfree_skb_any(tx_skb->skb); tx_skb->skb = NULL; return 1; - } else { - return 0; } + return 0; } static void nv_drain_tx(struct net_device *dev) @@ -1964,10 +1973,11 @@ static void nv_drain_tx(struct net_device *dev) np->tx_ring.ex[i].bufhigh = 0; np->tx_ring.ex[i].buflow = 0; } - if (nv_release_txskb(dev, &np->tx_skb[i])) + if (nv_release_txskb(np, &np->tx_skb[i])) dev->stats.tx_dropped++; np->tx_skb[i].dma = 0; np->tx_skb[i].dma_len = 0; + np->tx_skb[i].dma_single = 0; np->tx_skb[i].first_tx_desc = NULL; np->tx_skb[i].next_tx_ctx = NULL; } @@ -2171,6 +2181,7 @@ static int nv_start_xmit(struct sk_buff *skb, struct net_device *dev) np->put_tx_ctx->dma = pci_map_single(np->pci_dev, skb->data + offset, bcnt, PCI_DMA_TODEVICE); np->put_tx_ctx->dma_len = bcnt; + np->put_tx_ctx->dma_single = 1; put_tx->buf = cpu_to_le32(np->put_tx_ctx->dma); put_tx->flaglen = cpu_to_le32((bcnt-1) | tx_flags); @@ -2196,6 +2207,7 @@ static int nv_start_xmit(struct sk_buff *skb, struct net_device *dev) np->put_tx_ctx->dma = pci_map_page(np->pci_dev, frag->page, frag->page_offset+offset, bcnt, PCI_DMA_TODEVICE); np->put_tx_ctx->dma_len = bcnt; + np->put_tx_ctx->dma_single = 0; put_tx->buf = cpu_to_le32(np->put_tx_ctx->dma); put_tx->flaglen = cpu_to_le32((bcnt-1) | tx_flags); @@ -2291,6 +2303,7 @@ static int nv_start_xmit_optimized(struct sk_buff *skb, struct net_device *dev) np->put_tx_ctx->dma = pci_map_single(np->pci_dev, skb->data + offset, bcnt, PCI_DMA_TODEVICE); np->put_tx_ctx->dma_len = bcnt; + np->put_tx_ctx->dma_single = 1; put_tx->bufhigh = cpu_to_le32(dma_high(np->put_tx_ctx->dma)); put_tx->buflow = cpu_to_le32(dma_low(np->put_tx_ctx->dma)); put_tx->flaglen = cpu_to_le32((bcnt-1) | tx_flags); @@ -2317,6 +2330,7 @@ static int nv_start_xmit_optimized(struct sk_buff *skb, struct net_device *dev) np->put_tx_ctx->dma = pci_map_page(np->pci_dev, frag->page, frag->page_offset+offset, bcnt, PCI_DMA_TODEVICE); np->put_tx_ctx->dma_len = bcnt; + np->put_tx_ctx->dma_single = 0; put_tx->bufhigh = cpu_to_le32(dma_high(np->put_tx_ctx->dma)); put_tx->buflow = cpu_to_le32(dma_low(np->put_tx_ctx->dma)); put_tx->flaglen = cpu_to_le32((bcnt-1) | tx_flags); @@ -2434,10 +2448,7 @@ static int nv_tx_done(struct net_device *dev, int limit) dprintk(KERN_DEBUG "%s: nv_tx_done: flags 0x%x.\n", dev->name, flags); - pci_unmap_page(np->pci_dev, np->get_tx_ctx->dma, - np->get_tx_ctx->dma_len, - PCI_DMA_TODEVICE); - np->get_tx_ctx->dma = 0; + nv_unmap_txskb(np, np->get_tx_ctx); if (np->desc_ver == DESC_VER_1) { if (flags & NV_TX_LASTPACKET) { @@ -2502,10 +2513,7 @@ static int nv_tx_done_optimized(struct net_device *dev, int limit) dprintk(KERN_DEBUG "%s: nv_tx_done_optimized: flags 0x%x.\n", dev->name, flags); - pci_unmap_page(np->pci_dev, np->get_tx_ctx->dma, - np->get_tx_ctx->dma_len, - PCI_DMA_TODEVICE); - np->get_tx_ctx->dma = 0; + nv_unmap_txskb(np, np->get_tx_ctx); if (flags & NV_TX2_LASTPACKET) { if (!(flags & NV_TX2_ERROR)) @@ -5091,7 +5099,7 @@ static int nv_loopback_test(struct net_device *dev) dprintk(KERN_DEBUG "%s: loopback - did not receive test packet\n", dev->name); } - pci_unmap_page(np->pci_dev, test_dma_addr, + pci_unmap_single(np->pci_dev, test_dma_addr, (skb_end_pointer(tx_skb) - tx_skb->data), PCI_DMA_TODEVICE); dev_kfree_skb_any(tx_skb); -- cgit From 78c29bd95bd8d2c3bcf7932cb3ab8ae01cd8f58f Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 2 Jul 2009 04:04:45 +0000 Subject: forcedeth: Fix NAPI race. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Eric Dumazet a écrit : > Ingo Molnar a écrit : >>> The following changes since commit 52989765629e7d182b4f146050ebba0abf2cb0b7: >>> Linus Torvalds (1): >>> Merge git://git.kernel.org/.../davem/net-2.6 >>> >>> are available in the git repository at: >>> >>> master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6.git master >> Hm, something in this lot quickly wrecked networking here - see the >> tx timeout dump below. It starts with: >> >> [ 351.004596] WARNING: at net/sched/sch_generic.c:246 dev_watchdog+0x10b/0x19c() >> [ 351.011815] Hardware name: System Product Name >> [ 351.016220] NETDEV WATCHDOG: eth0 (forcedeth): transmit queue 0 timed out >> >> Config attached. Unfortunately i've got no time to do bisection >> today. > > > > forcedeth might have a problem, in its netif_wake_queue() logic, but > I could not see why a recent patch could make this problem visible now. > > CPU0/1: AMD Athlon(tm) 64 X2 Dual Core Processor 3800+ stepping 02 > is not a new cpu either :) > > forcedeth uses an internal tx_stop without appropriate barrier. > > Could you try following patch ? > > (random guess as I dont have much time right now) We might have a race in napi_schedule(), leaving interrupts disabled forever. I cannot test this patch, I dont have the hardware... Tested-by: Ingo Molnar Signed-off-by: David S. Miller --- drivers/net/forcedeth.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) (limited to 'drivers/net/forcedeth.c') diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c index 1094d292630..3b4e0766c7b 100644 --- a/drivers/net/forcedeth.c +++ b/drivers/net/forcedeth.c @@ -3514,11 +3514,13 @@ static irqreturn_t nv_nic_irq(int foo, void *data) nv_msi_workaround(np); #ifdef CONFIG_FORCEDETH_NAPI - napi_schedule(&np->napi); - - /* Disable furthur irq's - (msix not enabled with napi) */ - writel(0, base + NvRegIrqMask); + if (napi_schedule_prep(&np->napi)) { + /* + * Disable further irq's (msix not enabled with napi) + */ + writel(0, base + NvRegIrqMask); + __napi_schedule(&np->napi); + } #else do @@ -3615,12 +3617,13 @@ static irqreturn_t nv_nic_irq_optimized(int foo, void *data) nv_msi_workaround(np); #ifdef CONFIG_FORCEDETH_NAPI - napi_schedule(&np->napi); - - /* Disable furthur irq's - (msix not enabled with napi) */ - writel(0, base + NvRegIrqMask); - + if (napi_schedule_prep(&np->napi)) { + /* + * Disable further irq's (msix not enabled with napi) + */ + writel(0, base + NvRegIrqMask); + __napi_schedule(&np->napi); + } #else do { -- cgit