From: Keith Busch <kbusch@kernel.org>
To: linux-nvme@lists.infradead.org
Cc: sagi@grimberg.me, bigeasy@linutronix.de, ming.lei@redhat.com,
Keith Busch <kbusch@kernel.org>,
tglx@linutronix.de, hch@lst.de
Subject: [PATCHv3 1/4] nvme/pci: Disable interrupts for threaded handler
Date: Tue, 10 Dec 2019 02:56:19 +0900 [thread overview]
Message-ID: <20191209175622.1964-2-kbusch@kernel.org> (raw)
In-Reply-To: <20191209175622.1964-1-kbusch@kernel.org>
The nvme driver had always left the device in a state capable of sending
more interrupts while completions were being handled in the thread.
Re-entering the primary handler disrupts the threaded handler since
they run on the same CPU. The primary handler may also be detected as
spurious when it returns IRQ_WAKE_THREAD if the threaded handler does
not finish frequently enough due to completing many requests.
Disable the irq to ensure the primary handler will not be re-entered while
the threaded handler is running. Use the nvme specific interrupt mask
set/clear registers for MSI and legacy, and rely on the irq_flow_handler
to mask the interrupt for MSIx.
Signed-off-by: Keith Busch <kbusch@kernel.org>
---
drivers/nvme/host/pci.c | 26 ++++++++++++++++++++++----
1 file changed, 22 insertions(+), 4 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 365a2ddbeaa7..a0138e3ca0b9 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1036,12 +1036,30 @@ static irqreturn_t nvme_irq(int irq, void *data)
return ret;
}
+static irqreturn_t nvme_irq_thread(int irq, void *data)
+{
+ struct nvme_queue *nvmeq = data;
+ irqreturn_t ret = nvme_irq(irq, data);
+
+ if (!to_pci_dev(nvmeq->dev->dev)->msix_enabled)
+ writel(1 << nvmeq->cq_vector, nvmeq->dev->bar + NVME_REG_INTMC);
+
+ enable_irq(irq);
+ return ret;
+}
+
static irqreturn_t nvme_irq_check(int irq, void *data)
{
struct nvme_queue *nvmeq = data;
- if (nvme_cqe_pending(nvmeq))
- return IRQ_WAKE_THREAD;
- return IRQ_NONE;
+
+ if (!nvme_cqe_pending(nvmeq))
+ return IRQ_NONE;
+
+ if (!to_pci_dev(nvmeq->dev->dev)->msix_enabled)
+ writel(1 << nvmeq->cq_vector, nvmeq->dev->bar + NVME_REG_INTMS);
+
+ disable_irq_nosync(irq);
+ return IRQ_WAKE_THREAD;
}
/*
@@ -1499,7 +1517,7 @@ static int queue_request_irq(struct nvme_queue *nvmeq)
if (use_threaded_interrupts) {
return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
- nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
+ nvme_irq_thread, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
} else {
return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
--
2.21.0
_______________________________________________
linux-nvme mailing list
linux-nvme@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-nvme
next prev parent reply other threads:[~2019-12-09 17:57 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-09 17:56 [PATCHv3 0/4] nvme pci interrupt handling improvements Keith Busch
2019-12-09 17:56 ` Keith Busch [this message]
2019-12-10 15:12 ` [PATCHv3 1/4] nvme/pci: Disable interrupts for threaded handler Daniel Wagner
2019-12-10 15:28 ` Sebastian Andrzej Siewior
2019-12-10 15:54 ` Keith Busch
2019-12-10 16:44 ` Daniel Wagner
2019-12-10 16:57 ` Keith Busch
2019-12-10 17:11 ` Daniel Wagner
2019-12-12 9:09 ` Christoph Hellwig
2019-12-12 15:53 ` Keith Busch
2019-12-09 17:56 ` [PATCHv3 2/4] nvme/pci: Complete commands from primary handler Keith Busch
2019-12-10 20:00 ` Sagi Grimberg
2019-12-10 20:25 ` Keith Busch
2019-12-10 21:14 ` Sagi Grimberg
2019-12-11 17:35 ` Keith Busch
2019-12-12 0:40 ` Sagi Grimberg
2019-12-12 1:02 ` Keith Busch
2019-12-12 22:55 ` Ming Lei
2019-12-12 23:30 ` Keith Busch
2019-12-13 0:52 ` Ming Lei
2019-12-12 9:14 ` Christoph Hellwig
2019-12-09 17:56 ` [PATCHv3 3/4] nvme/pci: Remove use_threaded_interrupts Keith Busch
2019-12-12 9:14 ` Christoph Hellwig
2019-12-12 15:45 ` Keith Busch
2019-12-18 7:29 ` Ming Lei
2019-12-18 15:50 ` Keith Busch
2019-12-19 1:10 ` Ming Lei
2019-12-09 17:56 ` [PATCHv3 4/4] nvme/pci: Poll threaded completions Keith Busch
2019-12-10 17:43 ` Daniel Wagner
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