Revert "nvme: avoid cqe corruption when update at the same time as read"

This reverts commit 4369f33dfdd50a5011922d45830e2b69ba4067ce.

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index cbe8ad7ff43285e051796e69e35fc703cc2fd5b0..3ee056b8aa29d22d0c5ba2593e14888839047437 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -956,13 +956,6 @@ out:
        return ret;
 }
 
-/* We read the CQE phase first to check if the rest of the entry is valid */
-static inline bool nvme_cqe_valid(struct nvme_queue *nvmeq, u16 head,
-        u16 phase)
-{
-        return (le16_to_cpu(nvmeq->cqes[head].status) & 1) == phase;
-}
-
 static int nvme_process_cq(struct nvme_queue *nvmeq)
 {
        u16 head, phase;
@@ -970,10 +963,12 @@ static int nvme_process_cq(struct nvme_queue *nvmeq)
        head = nvmeq->cq_head;
        phase = nvmeq->cq_phase;
 
-       while (nvme_cqe_valid(nvmeq, head, phase)) {
+       for (;;) {
                void *ctx;
                nvme_completion_fn fn;
                struct nvme_completion cqe = nvmeq->cqes[head];
+               if ((le16_to_cpu(cqe.status) & 1) != phase)
+                       break;
                nvmeq->sq_head = le16_to_cpu(cqe.sq_head);
                if (++head == nvmeq->q_depth) {
                        head = 0;
@@ -1016,9 +1011,10 @@ static irqreturn_t nvme_irq(int irq, void *data)
 static irqreturn_t nvme_irq_check(int irq, void *data)
 {
        struct nvme_queue *nvmeq = data;
-        if (nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase))
-                return IRQ_WAKE_THREAD;
-        return IRQ_NONE;
+       struct nvme_completion cqe = nvmeq->cqes[nvmeq->cq_head];
+       if ((le16_to_cpu(cqe.status) & 1) != nvmeq->cq_phase)
+               return IRQ_NONE;
+       return IRQ_WAKE_THREAD;
 }
 
 /*