[PATCH v3] nvme: change return type of nvme_poll_cq() to bool

[PATCH v3] nvme: change return type of nvme_poll_cq() to bool

[Yongsoo Joo]

The nvme_poll_cq() function currently returns the number of CQEs
found, However, only one caller, nvme_poll(), requires a boolean
value to check whether any CQE was completed. The other callers do
not use the return value at all.

To better reflect its usage, update the return type of nvme_poll_cq()
from int to bool.

Signed-off-by: Yongsoo Joo <ysjoo@kookmin.ac.kr>
---
Changes from v2 to v3:
- Changed the return type of nvme_poll_cq() instead of nvme_poll(),
  as suggested by Keith Busch.
- Updated the patch subject to reflect this change.

Changes from v1 to v2:
- Changed the return type of nvme_poll() from int to bool, rather than
  modifying the internal return variable from bool to int, as
  suggested by Christoph Hellwig.
- Updated the patch subject by replacing "fix" with "change", as
  suggested by Keith Busch.

 drivers/nvme/host/pci.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 1a5ba80f1811..79d9b4c42b95 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1148,13 +1148,13 @@ static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
 	}
 }
 
-static inline int nvme_poll_cq(struct nvme_queue *nvmeq,
-			       struct io_comp_batch *iob)
+static inline bool nvme_poll_cq(struct nvme_queue *nvmeq,
+			        struct io_comp_batch *iob)
 {
-	int found = 0;
+	bool found = false;
 
 	while (nvme_cqe_pending(nvmeq)) {
-		found++;
+		found = true;
 		/*
 		 * load-load control dependency between phase and the rest of
 		 * the cqe requires a full read memory barrier
-- 
2.34.1


-- 

Re: [PATCH v3] nvme: change return type of nvme_poll_cq() to bool

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH v3] nvme: change return type of nvme_poll_cq() to bool

[Sagi Grimberg]

Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

Re: [PATCH v3] nvme: change return type of nvme_poll_cq() to bool

[Keith Busch]

On Mon, Dec 23, 2024 at 01:05:17AM +0000, Yongsoo Joo wrote:
> The nvme_poll_cq() function currently returns the number of CQEs
> found, However, only one caller, nvme_poll(), requires a boolean
> value to check whether any CQE was completed. The other callers do
> not use the return value at all.
> 
> To better reflect its usage, update the return type of nvme_poll_cq()
> from int to bool.

Thanks, applied to nvme-6.14.