[PATCH v6] nvme: Skip trace complete_rq on host path error

[PATCH v6] nvme: Skip trace complete_rq on host path error

[전민식]

From cfd386c2d769552c4dd32ec8ff5233ef34f9830d Mon Sep 17 00:00:00 2001
From: Minsik Jeon <hmi.jeon@samsung.com>
Date: Thu, 16 Apr 2026 10:43:00 +0900
Subject: [PATCH v6] nvme: Skip trace complete_rq on host path error

we were checking host_pathing_error before calling nvme_setup_cmd().
This is caused the command setup to be skipped entirely when a pathing
error occurred, making it impossible to trace the nvme command via
trace_cmd nvme_complete_rq().

As a result, when nvme_complete_rq() logged a completion with cmdid=0,
it was impossible to correlate the completion with the nvme command
request.

This patch Skip trace_nvme_complete_rq() on NVMe host path error.

Co-authored-by: Beomsoo Kim <beomsooo.kim@samsung.com>
Co-authored-by: Eunsoo Lee <euns212.lee@samsung.com>
Co-authored-by: Steven Seungcheol Lee <sc108.lee@samsung.com>
Signed-off-by: Minsik Jeon <hmi.jeon@samsung.com>
---
 drivers/nvme/host/core.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 1e33af94c24b..e92c97fad305 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -454,11 +454,10 @@ void nvme_end_req(struct request *req)
 	blk_mq_end_request(req, status);
 }
 
-void nvme_complete_rq(struct request *req)
+void __nvme_complete_rq(struct request *req)
 {
 	struct nvme_ctrl *ctrl = nvme_req(req)->ctrl;
 
-	trace_nvme_complete_rq(req);
 	nvme_cleanup_cmd(req);
 
 	/*
@@ -493,6 +492,12 @@ void nvme_complete_rq(struct request *req)
 		return;
 	}
 }
+
+void nvme_complete_rq(struct request *req)
+{
+	trace_nvme_complete_rq(req);
+	__nvme_complete_rq(req);
+}
 EXPORT_SYMBOL_GPL(nvme_complete_rq);
 
 void nvme_complete_batch_req(struct request *req)
@@ -513,7 +518,7 @@ blk_status_t nvme_host_path_error(struct request *req)
 {
 	nvme_req(req)->status = NVME_SC_HOST_PATH_ERROR;
 	blk_mq_set_request_complete(req);
-	nvme_complete_rq(req);
+	__nvme_complete_rq(req);
 	return BLK_STS_OK;
 }
 EXPORT_SYMBOL_GPL(nvme_host_path_error);
-- 
2.52.0

Re: [PATCH v6] nvme: Skip trace complete_rq on host path error

[Chaitanya Kulkarni]

On 4/15/26 18:07, 전민식 wrote:
>  From cfd386c2d769552c4dd32ec8ff5233ef34f9830d Mon Sep 17 00:00:00 2001
> From: Minsik Jeon<hmi.jeon@samsung.com>
> Date: Thu, 16 Apr 2026 10:43:00 +0900
> Subject: [PATCH v6] nvme: Skip trace complete_rq on host path error
>
> we were checking host_pathing_error before calling nvme_setup_cmd().
> This is caused the command setup to be skipped entirely when a pathing
> error occurred, making it impossible to trace the nvme command via
> trace_cmd nvme_complete_rq().
>
> As a result, when nvme_complete_rq() logged a completion with cmdid=0,
> it was impossible to correlate the completion with the nvme command
> request.
>
> This patch Skip trace_nvme_complete_rq() on NVMe host path error.
>
> Co-authored-by: Beomsoo Kim<beomsooo.kim@samsung.com>
> Co-authored-by: Eunsoo Lee<euns212.lee@samsung.com>
> Co-authored-by: Steven Seungcheol Lee<sc108.lee@samsung.com>
> Signed-off-by: Minsik Jeon<hmi.jeon@samsung.com>
> ---

Is it possible to send this patch using git send-email ?
Also, do you see any performance difference after this change ?
I don't expect any but it's better to document if any since
this is in the fast path.

-ck

Re: [PATCH v6] nvme: Skip trace complete_rq on host path error

[Keith Busch]

On Thu, Apr 16, 2026 at 10:07:13AM +0900, 전민식 wrote:
> Co-authored-by: Beomsoo Kim <beomsooo.kim@samsung.com>
> Co-authored-by: Eunsoo Lee <euns212.lee@samsung.com>
> Co-authored-by: Steven Seungcheol Lee <sc108.lee@samsung.com>

...

> -void nvme_complete_rq(struct request *req)
> +void __nvme_complete_rq(struct request *req)

You're missing the "static" declaration, which was present in the
original suggestion:

https://lore.kernel.org/linux-nvme/acVCnozG1WKPkq1L@kbusch-mbp/

Should I just apply my local copy? I think it's an original patch from
me at this point.

RE: Re: [PATCH v6] nvme: Skip trace complete_rq on host path error

[전민식]

On Thu, Apr 16, 2026 at 22:00 UTC, Keith Busch wrote:
> You're missing the "static" declaration, which was present in the
> original suggestion:
>
> https://lore.kernel.org/linux-nvme/acVCnozG1WKPkq1L@kbusch-mbp/
>
> Should I just apply my local copy? I think it's an original patch from
> me at this point.

Please go ahead and apply your local copy.
I appreciate your help in finalizing the patch.

Thanks,
Minsik Jeon