| Message ID | 20191006024516.19996-6-ming.lei@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blk-mq: improvement on handling IO during CPU hotplug | expand |
On 10/6/19 4:45 AM, Ming Lei wrote: > If hctx becomes dead, all in-queue IO requests aimed at this hctx have to > be re-submitted, so cover requests queued in scheduler queue. > > Cc: Bart Van Assche <bvanassche@acm.org> > Cc: Hannes Reinecke <hare@suse.com> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Keith Busch <keith.busch@intel.com> > Signed-off-by: Ming Lei <ming.lei@redhat.com> > --- > block/blk-mq.c | 30 +++++++++++++++++++++++++----- > 1 file changed, 25 insertions(+), 5 deletions(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 0b35fdbd1f17..94fd47cef1bc 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -2313,6 +2313,7 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) > enum hctx_type type; > bool hctx_dead; > struct request *rq; > + struct elevator_queue *e; > > hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead); > ctx = __blk_mq_get_ctx(hctx->queue, cpu); > @@ -2323,12 +2324,31 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) > hctx_dead = cpumask_first_and(hctx->cpumask, cpu_online_mask) >= > nr_cpu_ids; > > - spin_lock(&ctx->lock); > - if (!list_empty(&ctx->rq_lists[type])) { > - list_splice_init(&ctx->rq_lists[type], &tmp); > - blk_mq_hctx_clear_pending(hctx, ctx); > + e = hctx->queue->elevator; > + if (!e) { > + spin_lock(&ctx->lock); > + if (!list_empty(&ctx->rq_lists[type])) { > + list_splice_init(&ctx->rq_lists[type], &tmp); > + blk_mq_hctx_clear_pending(hctx, ctx); > + } > + spin_unlock(&ctx->lock); > + } else if (hctx_dead) { > + LIST_HEAD(sched_tmp); > + > + while ((rq = e->type->ops.dispatch_request(hctx))) { > + if (rq->mq_hctx != hctx) > + list_add(&rq->queuelist, &sched_tmp); > + else > + list_add(&rq->queuelist, &tmp); > + } > + > + while (!list_empty(&sched_tmp)) { > + rq = list_entry(sched_tmp.next, struct request, > + queuelist); > + list_del_init(&rq->queuelist); > + blk_mq_sched_insert_request(rq, true, true, true); > + } > } > - spin_unlock(&ctx->lock); > > if (list_empty(&tmp)) > return 0; > Reviewed-by: Hannes Reinecke <hare@suse.com> Cheers, Hannes
diff --git a/block/blk-mq.c b/block/blk-mq.c index 0b35fdbd1f17..94fd47cef1bc 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2313,6 +2313,7 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) enum hctx_type type; bool hctx_dead; struct request *rq; + struct elevator_queue *e; hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead); ctx = __blk_mq_get_ctx(hctx->queue, cpu); @@ -2323,12 +2324,31 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) hctx_dead = cpumask_first_and(hctx->cpumask, cpu_online_mask) >= nr_cpu_ids; - spin_lock(&ctx->lock); - if (!list_empty(&ctx->rq_lists[type])) { - list_splice_init(&ctx->rq_lists[type], &tmp); - blk_mq_hctx_clear_pending(hctx, ctx); + e = hctx->queue->elevator; + if (!e) { + spin_lock(&ctx->lock); + if (!list_empty(&ctx->rq_lists[type])) { + list_splice_init(&ctx->rq_lists[type], &tmp); + blk_mq_hctx_clear_pending(hctx, ctx); + } + spin_unlock(&ctx->lock); + } else if (hctx_dead) { + LIST_HEAD(sched_tmp); + + while ((rq = e->type->ops.dispatch_request(hctx))) { + if (rq->mq_hctx != hctx) + list_add(&rq->queuelist, &sched_tmp); + else + list_add(&rq->queuelist, &tmp); + } + + while (!list_empty(&sched_tmp)) { + rq = list_entry(sched_tmp.next, struct request, + queuelist); + list_del_init(&rq->queuelist); + blk_mq_sched_insert_request(rq, true, true, true); + } } - spin_unlock(&ctx->lock); if (list_empty(&tmp)) return 0;
If hctx becomes dead, all in-queue IO requests aimed at this hctx have to be re-submitted, so cover requests queued in scheduler queue. Cc: Bart Van Assche <bvanassche@acm.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Keith Busch <keith.busch@intel.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> --- block/blk-mq.c | 30 +++++++++++++++++++++++++----- 1 file changed, 25 insertions(+), 5 deletions(-)