nvme-pci: open-code polling logic in nvme_poll

Given that the code is simple enough it seems better
then passing a tag by reference for each call site, also
we can now get rid of __nvme_process_cq.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 21 insertions, 19 deletions

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index d309b6c90511..2a9ee769ce9e 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -785,7 +785,7 @@ static inline bool nvme_read_cqe(struct nvme_queue *nvmeq,
         return false;
 }
 
-static void __nvme_process_cq(struct nvme_queue *nvmeq, int *tag)
+static void nvme_process_cq(struct nvme_queue *nvmeq)
 {
         struct nvme_completion cqe;
         int consumed = 0;
@@ -793,11 +793,6 @@ static void __nvme_process_cq(struct nvme_queue *nvmeq, int *tag)
         while (nvme_read_cqe(nvmeq, &cqe)) {
                 nvme_handle_cqe(nvmeq, &cqe);
                 consumed++;
-
-                if (tag && *tag == cqe.command_id) {
-                        *tag = -1;
-                        break;
-                }
         }
 
         if (consumed) {
@@ -806,11 +801,6 @@ static void __nvme_process_cq(struct nvme_queue *nvmeq, int *tag)
         }
 }
 
-static void nvme_process_cq(struct nvme_queue *nvmeq)
-{
-        __nvme_process_cq(nvmeq, NULL);
-}
-
 static irqreturn_t nvme_irq(int irq, void *data)
 {
         irqreturn_t result;
@@ -833,16 +823,28 @@ static irqreturn_t nvme_irq_check(int irq, void *data)
 
 static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag)
 {
-        if (nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase)) {
-                spin_lock_irq(&nvmeq->q_lock);
-                __nvme_process_cq(nvmeq, &tag);
-                spin_unlock_irq(&nvmeq->q_lock);
+        struct nvme_completion cqe;
+        int found = 0, consumed = 0;
 
-                if (tag == -1)
-                        return 1;
-        }
+        if (!nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase))
+                return 0;
 
-        return 0;
+        spin_lock_irq(&nvmeq->q_lock);
+        while (nvme_read_cqe(nvmeq, &cqe)) {
+                nvme_handle_cqe(nvmeq, &cqe);
+                consumed++;
+
+                if (tag == cqe.command_id) {
+                        found = 1;
+                        break;
+                }
+       }
+
+        if (consumed)
+                nvme_ring_cq_doorbell(nvmeq);
+        spin_unlock_irq(&nvmeq->q_lock);
+
+        return found;
 }
 
 static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)