From: Sasha Levin <sashal@kernel.org> To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yannick Vignon <yannick.vignon@nxp.com>, Jakub Kicinski <kuba@kernel.org>, Sasha Levin <sashal@kernel.org>, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 5.4 23/23] net: stmmac: Do not enable RX FIFO overflow interrupts Date: Wed, 12 May 2021 14:04:07 -0400 [thread overview] Message-ID: <20210512180408.665338-23-sashal@kernel.org> (raw) In-Reply-To: <20210512180408.665338-1-sashal@kernel.org> From: Yannick Vignon <yannick.vignon@nxp.com> [ Upstream commit 8a7cb245cf28cb3e541e0d6c8624b95d079e155b ] The RX FIFO overflows when the system is not able to process all received packets and they start accumulating (first in the DMA queue in memory, then in the FIFO). An interrupt is then raised for each overflowing packet and handled in stmmac_interrupt(). This is counter-productive, since it brings the system (or more likely, one CPU core) to its knees to process the FIFO overflow interrupts. stmmac_interrupt() handles overflow interrupts by writing the rx tail ptr into the corresponding hardware register (according to the MAC spec, this has the effect of restarting the MAC DMA). However, without freeing any rx descriptors, the DMA stops right away, and another overflow interrupt is raised as the FIFO overflows again. Since the DMA is already restarted at the end of stmmac_rx_refill() after freeing descriptors, disabling FIFO overflow interrupts and the corresponding handling code has no side effect, and eliminates the interrupt storm when the RX FIFO overflows. Signed-off-by: Yannick Vignon <yannick.vignon@nxp.com> Link: https://lore.kernel.org/r/20210506143312.20784-1-yannick.vignon@oss.nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c | 7 +------ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 14 ++------------ 2 files changed, 3 insertions(+), 18 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c index a41ac13cc4e5..0d993f4b701c 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c @@ -211,7 +211,7 @@ static void dwmac4_dma_rx_chan_op_mode(void __iomem *ioaddr, int mode, u32 channel, int fifosz, u8 qmode) { unsigned int rqs = fifosz / 256 - 1; - u32 mtl_rx_op, mtl_rx_int; + u32 mtl_rx_op; mtl_rx_op = readl(ioaddr + MTL_CHAN_RX_OP_MODE(channel)); @@ -282,11 +282,6 @@ static void dwmac4_dma_rx_chan_op_mode(void __iomem *ioaddr, int mode, } writel(mtl_rx_op, ioaddr + MTL_CHAN_RX_OP_MODE(channel)); - - /* Enable MTL RX overflow */ - mtl_rx_int = readl(ioaddr + MTL_CHAN_INT_CTRL(channel)); - writel(mtl_rx_int | MTL_RX_OVERFLOW_INT_EN, - ioaddr + MTL_CHAN_INT_CTRL(channel)); } static void dwmac4_dma_tx_chan_op_mode(void __iomem *ioaddr, int mode, diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 8e7c60e02fa0..10d28be73f45 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3855,7 +3855,6 @@ static irqreturn_t stmmac_interrupt(int irq, void *dev_id) /* To handle GMAC own interrupts */ if ((priv->plat->has_gmac) || xmac) { int status = stmmac_host_irq_status(priv, priv->hw, &priv->xstats); - int mtl_status; if (unlikely(status)) { /* For LPI we need to save the tx status */ @@ -3866,17 +3865,8 @@ static irqreturn_t stmmac_interrupt(int irq, void *dev_id) } for (queue = 0; queue < queues_count; queue++) { - struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue]; - - mtl_status = stmmac_host_mtl_irq_status(priv, priv->hw, - queue); - if (mtl_status != -EINVAL) - status |= mtl_status; - - if (status & CORE_IRQ_MTL_RX_OVERFLOW) - stmmac_set_rx_tail_ptr(priv, priv->ioaddr, - rx_q->rx_tail_addr, - queue); + status = stmmac_host_mtl_irq_status(priv, priv->hw, + queue); } /* PCS link status */ -- 2.30.2
WARNING: multiple messages have this Message-ID (diff)
From: Sasha Levin <sashal@kernel.org> To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yannick Vignon <yannick.vignon@nxp.com>, Jakub Kicinski <kuba@kernel.org>, Sasha Levin <sashal@kernel.org>, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 5.4 23/23] net: stmmac: Do not enable RX FIFO overflow interrupts Date: Wed, 12 May 2021 14:04:07 -0400 [thread overview] Message-ID: <20210512180408.665338-23-sashal@kernel.org> (raw) In-Reply-To: <20210512180408.665338-1-sashal@kernel.org> From: Yannick Vignon <yannick.vignon@nxp.com> [ Upstream commit 8a7cb245cf28cb3e541e0d6c8624b95d079e155b ] The RX FIFO overflows when the system is not able to process all received packets and they start accumulating (first in the DMA queue in memory, then in the FIFO). An interrupt is then raised for each overflowing packet and handled in stmmac_interrupt(). This is counter-productive, since it brings the system (or more likely, one CPU core) to its knees to process the FIFO overflow interrupts. stmmac_interrupt() handles overflow interrupts by writing the rx tail ptr into the corresponding hardware register (according to the MAC spec, this has the effect of restarting the MAC DMA). However, without freeing any rx descriptors, the DMA stops right away, and another overflow interrupt is raised as the FIFO overflows again. Since the DMA is already restarted at the end of stmmac_rx_refill() after freeing descriptors, disabling FIFO overflow interrupts and the corresponding handling code has no side effect, and eliminates the interrupt storm when the RX FIFO overflows. Signed-off-by: Yannick Vignon <yannick.vignon@nxp.com> Link: https://lore.kernel.org/r/20210506143312.20784-1-yannick.vignon@oss.nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c | 7 +------ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 14 ++------------ 2 files changed, 3 insertions(+), 18 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c index a41ac13cc4e5..0d993f4b701c 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c @@ -211,7 +211,7 @@ static void dwmac4_dma_rx_chan_op_mode(void __iomem *ioaddr, int mode, u32 channel, int fifosz, u8 qmode) { unsigned int rqs = fifosz / 256 - 1; - u32 mtl_rx_op, mtl_rx_int; + u32 mtl_rx_op; mtl_rx_op = readl(ioaddr + MTL_CHAN_RX_OP_MODE(channel)); @@ -282,11 +282,6 @@ static void dwmac4_dma_rx_chan_op_mode(void __iomem *ioaddr, int mode, } writel(mtl_rx_op, ioaddr + MTL_CHAN_RX_OP_MODE(channel)); - - /* Enable MTL RX overflow */ - mtl_rx_int = readl(ioaddr + MTL_CHAN_INT_CTRL(channel)); - writel(mtl_rx_int | MTL_RX_OVERFLOW_INT_EN, - ioaddr + MTL_CHAN_INT_CTRL(channel)); } static void dwmac4_dma_tx_chan_op_mode(void __iomem *ioaddr, int mode, diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 8e7c60e02fa0..10d28be73f45 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3855,7 +3855,6 @@ static irqreturn_t stmmac_interrupt(int irq, void *dev_id) /* To handle GMAC own interrupts */ if ((priv->plat->has_gmac) || xmac) { int status = stmmac_host_irq_status(priv, priv->hw, &priv->xstats); - int mtl_status; if (unlikely(status)) { /* For LPI we need to save the tx status */ @@ -3866,17 +3865,8 @@ static irqreturn_t stmmac_interrupt(int irq, void *dev_id) } for (queue = 0; queue < queues_count; queue++) { - struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue]; - - mtl_status = stmmac_host_mtl_irq_status(priv, priv->hw, - queue); - if (mtl_status != -EINVAL) - status |= mtl_status; - - if (status & CORE_IRQ_MTL_RX_OVERFLOW) - stmmac_set_rx_tail_ptr(priv, priv->ioaddr, - rx_q->rx_tail_addr, - queue); + status = stmmac_host_mtl_irq_status(priv, priv->hw, + queue); } /* PCS link status */ -- 2.30.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-05-12 19:57 UTC|newest] Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-05-12 18:03 [PATCH AUTOSEL 5.4 01/23] ARM: 9058/1: cache-v7: refactor v7_invalidate_l1 to avoid clobbering r5/r6 Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 02/23] PCI: thunder: Fix compile testing Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 03/23] dmaengine: dw-edma: Fix crash on loading/unloading driver Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 04/23] ARM: 9066/1: ftrace: pause/unpause function graph tracer in cpu_suspend() Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 05/23] f2fs: fix to avoid out-of-bounds memory access Sasha Levin 2021-05-12 18:03 ` [f2fs-dev] " Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 06/23] ACPI / hotplug / PCI: Fix reference count leak in enable_slot() Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 07/23] Input: elants_i2c - do not bind to i2c-hid compatible ACPI instantiated devices Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 08/23] Input: silead - add workaround for x86 BIOS-es which bring the chip up in a stuck state Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 09/23] um: Mark all kernel symbols as local Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 10/23] um: Disable CONFIG_GCOV with MODULES Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 11/23] ARM: 9075/1: kernel: Fix interrupted SMC calls Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 12/23] scripts/recordmcount.pl: Fix RISC-V regex for clang Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 13/23] riscv: Workaround mcount name prior to clang-13 Sasha Levin 2021-05-12 18:03 ` Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 14/23] scsi: lpfc: Fix illegal memory access on Abort IOCBs Sasha Levin 2021-05-12 18:03 ` [PATCH AUTOSEL 5.4 15/23] ceph: fix fscache invalidation Sasha Levin 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 16/23] scsi: target: tcmu: Return from tcmu_handle_completions() if cmd_id not found Sasha Levin 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 17/23] bridge: Fix possible races between assigning rx_handler_data and setting IFF_BRIDGE_PORT bit Sasha Levin 2021-05-12 18:04 ` [Bridge] " Sasha Levin 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 18/23] drm/amd/display: Fix two cursor duplication when using overlay Sasha Levin 2021-05-12 18:04 ` Sasha Levin 2021-05-12 18:04 ` Sasha Levin 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 19/23] gpiolib: acpi: Add quirk to ignore EC wakeups on Dell Venue 10 Pro 5055 Sasha Levin 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 20/23] ALSA: hda: generic: change the DAC ctl name for LO+SPK or LO+HP Sasha Levin 2021-05-12 18:04 ` Sasha Levin 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 21/23] block: reexpand iov_iter after read/write Sasha Levin 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 22/23] lib: stackdepot: turn depot_lock spinlock to raw_spinlock Sasha Levin 2021-05-12 18:04 ` Sasha Levin [this message] 2021-05-12 18:04 ` [PATCH AUTOSEL 5.4 23/23] net: stmmac: Do not enable RX FIFO overflow interrupts Sasha Levin
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=20210512180408.665338-23-sashal@kernel.org \ --to=sashal@kernel.org \ --cc=kuba@kernel.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-stm32@st-md-mailman.stormreply.com \ --cc=netdev@vger.kernel.org \ --cc=stable@vger.kernel.org \ --cc=yannick.vignon@nxp.com \ /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.