On 6/27/22 20:16, Keith Busch wrote:
On Mon, Jun 27, 2022 at 04:43:35PM -0700, Bart Van Assche wrote:
@@ -854,6 +854,12 @@ static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
if (req->cmd_flags & REQ_RAHEAD)
dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
+ if (blk_queue_pipeline_zoned_writes(req->q) &&
+ blk_rq_is_seq_zone_write(req))
+ nvme_req(req)->max_retries =
+ min(0UL + type_max(typeof(nvme_req(req)->max_retries)),
+ nvme_req(req)->max_retries + req->q->nr_requests);
I can't make much sense of what the above is trying to accomplish. This
reevaluates max_retries every time the request is retried, and the new
max_retries is based on the previous max_retries?
Hi Keith,
Thanks for your question. It made me realize that the above code should be
moved. How about replacing patch 8/8 with the (untested) patch below?
Thanks,
Bart.
Subject: [PATCH] nvme: Enable pipelining of zoned writes
Enabling pipelining for zoned writes. Increase the number of retries
for zoned writes to the maximum number of outstanding commands per hardware
queue.
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index aeeaca1c3197..6a0b824a343f 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -630,10 +630,15 @@ EXPORT_SYMBOL_NS_GPL(nvme_put_ns, NVME_TARGET_PASSTHRU);
static inline void nvme_clear_nvme_request(struct request *req)
{
+ u32 max_retries = nvme_max_retries;
+
nvme_req(req)->status = 0;
nvme_req(req)->retries = 0;
nvme_req(req)->flags = 0;
- nvme_req(req)->max_retries = nvme_max_retries;
+ if (blk_queue_pipeline_zoned_writes(req->q) &&
+ blk_rq_is_seq_zone_write(req))
+ max_retries += req->q->nr_requests;
+ nvme_req(req)->max_retries = min(0xffU, max_retries);
req->rq_flags |= RQF_DONTPREP;
}
diff --git a/drivers/nvme/host/zns.c b/drivers/nvme/host/zns.c
index 9f81beb4df4e..0b10db3b8d3a 100644
--- a/drivers/nvme/host/zns.c
+++ b/drivers/nvme/host/zns.c
@@ -54,6 +54,8 @@ int nvme_update_zone_info(struct nvme_ns *ns, unsigned lbaf)
struct nvme_id_ns_zns *id;
int status;
+ blk_queue_flag_set(QUEUE_FLAG_PIPELINE_ZONED_WRITES, ns->queue);
+
/* Driver requires zone append support */
if ((le32_to_cpu(log->iocs[nvme_cmd_zone_append]) &
NVME_CMD_EFFECTS_CSUPP)) {
