[PATCH AUTOSEL 6.14 08/23] nvmet: pci-epf: cleanup nvmet_pci_epf_raise_irq()

Sasha Levin
2025-05-19T21:21:44Z

From: Damien Le Moal <dlemoal@kernel.org>

[ Upstream commit 4236e600bf902202214aa6277e84c4738c56f762 ]

There is no point in taking the controller irq_lock and calling
nvmet_pci_epf_should_raise_irq() for a completion queue which does not
have IRQ enabled (NVMET_PCI_EPF_Q_IRQ_ENABLED flag is not set).
Move the test for the NVMET_PCI_EPF_Q_IRQ_ENABLED flag out of
nvmet_pci_epf_should_raise_irq() to the top of nvmet_pci_epf_raise_irq()
to return early when no IRQ should be raised.

Also, use dev_err_ratelimited() to avoid a message storm under load when
raising IRQs is failing.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/nvme/target/pci-epf.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/nvme/target/pci-epf.c b/drivers/nvme/target/pci-epf.c
index bc1daa9aede9d..80d857798bddd 100644
--- a/drivers/nvme/target/pci-epf.c
+++ b/drivers/nvme/target/pci-epf.c
@@ -596,9 +596,6 @@ static bool nvmet_pci_epf_should_raise_irq(struct nvmet_pci_epf_ctrl *ctrl,
struct nvmet_pci_epf_irq_vector *iv = cq->iv;
bool ret;

- if (!test_bit(NVMET_PCI_EPF_Q_IRQ_ENABLED, &cq->flags))
- return false;
-
/* IRQ coalescing for the admin queue is not allowed. */
if (!cq->qid)
return true;
@@ -625,7 +622,8 @@ static void nvmet_pci_epf_raise_irq(struct nvmet_pci_epf_ctrl *ctrl,
struct pci_epf *epf = nvme_epf->epf;
int ret = 0;

- if (!test_bit(NVMET_PCI_EPF_Q_LIVE, &cq->flags))
+ if (!test_bit(NVMET_PCI_EPF_Q_LIVE, &cq->flags) ||
+ !test_bit(NVMET_PCI_EPF_Q_IRQ_ENABLED, &cq->flags))
return;

mutex_lock(&ctrl->irq_lock);
@@ -656,7 +654,9 @@ static void nvmet_pci_epf_raise_irq(struct nvmet_pci_epf_ctrl *ctrl,
}

if (ret)
- dev_err(ctrl->dev, "Failed to raise IRQ (err=%d)\n", ret);
+ dev_err_ratelimited(ctrl->dev,
+ "CQ[%u]: Failed to raise IRQ (err=%d)\n",
+ cq->qid, ret);

unlock:
mutex_unlock(&ctrl->irq_lock);
--
2.39.5