block: introduce 'blk_mq_ctx' parameter to blk_get_flush_queue
This patch adds 'blk_mq_ctx' parameter to blk_get_flush_queue(),
so that this function can find the corresponding blk_flush_queue
bound with current mq context since the flush queue will become
per hw-queue.
For legacy queue, the parameter can be simply 'NULL'.
For multiqueue case, the parameter should be set as the context
from which the related request is originated. With this context
info, the hw queue and related flush queue can be found easily.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index dba0a83..b1dd4e0 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -390,7 +390,7 @@
* be drained. Check all the queues and counters.
*/
if (drain_all) {
- struct blk_flush_queue *fq = blk_get_flush_queue(q);
+ struct blk_flush_queue *fq = blk_get_flush_queue(q, NULL);
drain |= !list_empty(&q->queue_head);
for (i = 0; i < 2; i++) {
drain |= q->nr_rqs[i];
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 9bc5b4f..004d95e 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -223,7 +223,7 @@
bool queued = false;
struct request *rq, *n;
unsigned long flags = 0;
- struct blk_flush_queue *fq = blk_get_flush_queue(q);
+ struct blk_flush_queue *fq = blk_get_flush_queue(q, flush_rq->mq_ctx);
if (q->mq_ops) {
spin_lock_irqsave(&fq->mq_flush_lock, flags);
@@ -319,7 +319,7 @@
static void flush_data_end_io(struct request *rq, int error)
{
struct request_queue *q = rq->q;
- struct blk_flush_queue *fq = blk_get_flush_queue(q);
+ struct blk_flush_queue *fq = blk_get_flush_queue(q, NULL);
/*
* After populating an empty queue, kick it to avoid stall. Read
@@ -333,11 +333,10 @@
{
struct request_queue *q = rq->q;
struct blk_mq_hw_ctx *hctx;
- struct blk_mq_ctx *ctx;
+ struct blk_mq_ctx *ctx = rq->mq_ctx;
unsigned long flags;
- struct blk_flush_queue *fq = blk_get_flush_queue(q);
+ struct blk_flush_queue *fq = blk_get_flush_queue(q, ctx);
- ctx = rq->mq_ctx;
hctx = q->mq_ops->map_queue(q, ctx->cpu);
/*
@@ -367,7 +366,7 @@
struct request_queue *q = rq->q;
unsigned int fflags = q->flush_flags; /* may change, cache */
unsigned int policy = blk_flush_policy(fflags, rq);
- struct blk_flush_queue *fq = blk_get_flush_queue(q);
+ struct blk_flush_queue *fq = blk_get_flush_queue(q, rq->mq_ctx);
/*
* @policy now records what operations need to be done. Adjust
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 59ca796..53b6def1 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -518,7 +518,8 @@
struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag)
{
struct request *rq = tags->rqs[tag];
- struct blk_flush_queue *fq = blk_get_flush_queue(rq->q);
+ /* mq_ctx of flush rq is always cloned from the corresponding req */
+ struct blk_flush_queue *fq = blk_get_flush_queue(rq->q, rq->mq_ctx);
if (!is_flush_request(rq, fq, tag))
return rq;
diff --git a/block/blk.h b/block/blk.h
index 9eaa6e9..7ecdd85 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -29,7 +29,7 @@
extern struct ida blk_queue_ida;
static inline struct blk_flush_queue *blk_get_flush_queue(
- struct request_queue *q)
+ struct request_queue *q, struct blk_mq_ctx *ctx)
{
return q->fq;
}
@@ -106,7 +106,7 @@
static inline struct request *__elv_next_request(struct request_queue *q)
{
struct request *rq;
- struct blk_flush_queue *fq = blk_get_flush_queue(q);
+ struct blk_flush_queue *fq = blk_get_flush_queue(q, NULL);
while (1) {
if (!list_empty(&q->queue_head)) {