+static void blk_bio_poll_post_submit(struct bio *bio, blk_qc_t cookie) +{ + bio->bi_iter.bi_private_data = cookie; +} +
Hey Ming, thinking about nvme-mpath, I'm thinking that this should be an exported function for failover. nvme-mpath updates bio.bi_dev when re-submitting I/Os to an alternate path, so I'm thinking that if this function is exported then nvme-mpath could do as little as the below to allow polling? -- diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c index 92adebfaf86f..e562e296153b 100644 --- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -345,6 +345,7 @@ static void nvme_requeue_work(struct work_struct *work) struct nvme_ns_head *head = container_of(work, struct nvme_ns_head, requeue_work); struct bio *bio, *next; + blk_qc_t cookie; spin_lock_irq(&head->requeue_lock); next = bio_list_get(&head->requeue_list); @@ -359,7 +360,8 @@ static void nvme_requeue_work(struct work_struct *work) * path. */ bio_set_dev(bio, head->disk->part0); - submit_bio_noacct(bio); + cookie = submit_bio_noacct(bio); + blk_bio_poll_post_submit(bio, cookie); } } -- I/O failover will create misalignment from the polling context cpu and the submission cpu (running requeue_work), but I don't see if there is something that would break here... Thoughts? -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel