[PATCH 1/6] nvme: don't disable local ints for polled queue
From: Jens Axboe <axboe@kernel.dk>
Date: 2018-11-10 15:13:12
Also in:
linux-nvme
Subsystem:
nvm express driver, the rest · Maintainers:
Keith Busch, Jens Axboe, Christoph Hellwig, Sagi Grimberg, Linus Torvalds
A polled queued doesn't trigger interrupts, so it's always safe to grab the queue lock without disabling interrupts. Cc: Keith Busch <redacted> Cc: linux-nvme@lists.infradead.org Signed-off-by: Jens Axboe <axboe@kernel.dk> --- drivers/nvme/host/pci.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 6aa86dfcb32c..a6e3fbddfadf 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c@@ -1061,15 +1061,26 @@ static irqreturn_t nvme_irq_check(int irq, void *data) static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag) { + unsigned long flags = 0; /* gcc 7.x fail */ u16 start, end; - bool found; + bool found, has_irq; if (!nvme_cqe_pending(nvmeq)) return 0; - spin_lock_irq(&nvmeq->cq_lock); + /* + * Polled queue doesn't have an IRQ, no need to disable ints + */ + has_irq = !nvmeq->polled; + if (has_irq) + local_irq_save(flags); + + spin_lock(&nvmeq->cq_lock); found = nvme_process_cq(nvmeq, &start, &end, tag); - spin_unlock_irq(&nvmeq->cq_lock); + spin_unlock(&nvmeq->cq_lock); + + if (has_irq) + local_irq_restore(flags); nvme_complete_cqes(nvmeq, start, end); return found;
--
2.17.1