[PATCH AUTOSEL 5.1 019/375] blk-mq: split blk_mq_alloc_and_init_hctx into two parts

Sasha Levin
2019-05-22T20:03:03Z

From: Ming Lei <ming.lei@redhat.com>

[ Upstream commit 7c6c5b7c9186e3fb5b10afb8e5f710ae661144c6 ]

Split blk_mq_alloc_and_init_hctx into two parts, and one is
blk_mq_alloc_hctx() for allocating all hctx resources, another
is blk_mq_init_hctx() for initializing hctx, which serves as
counter-part of blk_mq_exit_hctx().

Cc: Dongli Zhang <dongli.zhang@oracle.com>
Cc: James Smart <james.smart@broadcom.com>
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Cc: linux-scsi@vger.kernel.org
Cc: Martin K . Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James E . J . Bottomley <jejb@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
block/blk-mq.c | 139 ++++++++++++++++++++++++++-----------------------
1 file changed, 75 insertions(+), 64 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index fc60ed7e940ea..24e3ae3bd710e 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2289,15 +2289,65 @@ static void blk_mq_exit_hw_queues(struct request_queue *q,
}
}

+static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set)
+{
+ int hw_ctx_size = sizeof(struct blk_mq_hw_ctx);
+
+ BUILD_BUG_ON(ALIGN(offsetof(struct blk_mq_hw_ctx, srcu),
+ __alignof__(struct blk_mq_hw_ctx)) !=
+ sizeof(struct blk_mq_hw_ctx));
+
+ if (tag_set->flags & BLK_MQ_F_BLOCKING)
+ hw_ctx_size += sizeof(struct srcu_struct);
+
+ return hw_ctx_size;
+}
+
static int blk_mq_init_hctx(struct request_queue *q,
struct blk_mq_tag_set *set,
struct blk_mq_hw_ctx *hctx, unsigned hctx_idx)
{
- int node;
+ hctx->queue_num = hctx_idx;
+
+ cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead);
+
+ hctx->tags = set->tags[hctx_idx];
+
+ if (set->ops->init_hctx &&
+ set->ops->init_hctx(hctx, set->driver_data, hctx_idx))
+ goto unregister_cpu_notifier;

- node = hctx->numa_node;
+ if (blk_mq_init_request(set, hctx->fq->flush_rq, hctx_idx,
+ hctx->numa_node))
+ goto exit_hctx;
+ return 0;
+
+ exit_hctx:
+ if (set->ops->exit_hctx)
+ set->ops->exit_hctx(hctx, hctx_idx);
+ unregister_cpu_notifier:
+ blk_mq_remove_cpuhp(hctx);
+ return -1;
+}
+
+static struct blk_mq_hw_ctx *
+blk_mq_alloc_hctx(struct request_queue *q, struct blk_mq_tag_set *set,
+ int node)
+{
+ struct blk_mq_hw_ctx *hctx;
+ gfp_t gfp = GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY;
+
+ hctx = kzalloc_node(blk_mq_hw_ctx_size(set), gfp, node);
+ if (!hctx)
+ goto fail_alloc_hctx;
+
+ if (!zalloc_cpumask_var_node(&hctx->cpumask, gfp, node))
+ goto free_hctx;
+
+ atomic_set(&hctx->nr_active, 0);
if (node == NUMA_NO_NODE)
- node = hctx->numa_node = set->numa_node;
+ node = set->numa_node;
+ hctx->numa_node = node;

INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn);
spin_lock_init(&hctx->lock);
@@ -2305,58 +2355,45 @@ static int blk_mq_init_hctx(struct request_queue *q,
hctx->queue = q;
hctx->flags = set->flags & ~BLK_MQ_F_TAG_SHARED;

- cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead);
-
- hctx->tags = set->tags[hctx_idx];
-
/*
* Allocate space for all possible cpus to avoid allocation at
* runtime
*/
hctx->ctxs = kmalloc_array_node(nr_cpu_ids, sizeof(void *),
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node);
+ gfp, node);
if (!hctx->ctxs)
- goto unregister_cpu_notifier;
+ goto free_cpumask;

if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8),
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node))
+ gfp, node))
goto free_ctxs;
-
hctx->nr_ctx = 0;

spin_lock_init(&hctx->dispatch_wait_lock);
init_waitqueue_func_entry(&hctx->dispatch_wait, blk_mq_dispatch_wake);
INIT_LIST_HEAD(&hctx->dispatch_wait.entry);

- if (set->ops->init_hctx &&
- set->ops->init_hctx(hctx, set->driver_data, hctx_idx))
- goto free_bitmap;
-
hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size,
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY);
+ gfp);
if (!hctx->fq)
- goto exit_hctx;
-
- if (blk_mq_init_request(set, hctx->fq->flush_rq, hctx_idx, node))
- goto free_fq;
+ goto free_bitmap;

if (hctx->flags & BLK_MQ_F_BLOCKING)
init_srcu_struct(hctx->srcu);
+ blk_mq_hctx_kobj_init(hctx);

- return 0;
+ return hctx;

- free_fq:
- blk_free_flush_queue(hctx->fq);
- exit_hctx:
- if (set->ops->exit_hctx)
- set->ops->exit_hctx(hctx, hctx_idx);
free_bitmap:
sbitmap_free(&hctx->ctx_map);
free_ctxs:
kfree(hctx->ctxs);
- unregister_cpu_notifier:
- blk_mq_remove_cpuhp(hctx);
- return -1;
+ free_cpumask:
+ free_cpumask_var(hctx->cpumask);
+ free_hctx:
+ kfree(hctx);
+ fail_alloc_hctx:
+ return NULL;
}

static void blk_mq_init_cpu_queues(struct request_queue *q,
@@ -2700,51 +2737,25 @@ struct request_queue *blk_mq_init_sq_queue(struct blk_mq_tag_set *set,
}
EXPORT_SYMBOL(blk_mq_init_sq_queue);

-static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set)
-{
- int hw_ctx_size = sizeof(struct blk_mq_hw_ctx);
-
- BUILD_BUG_ON(ALIGN(offsetof(struct blk_mq_hw_ctx, srcu),
- __alignof__(struct blk_mq_hw_ctx)) !=
- sizeof(struct blk_mq_hw_ctx));
-
- if (tag_set->flags & BLK_MQ_F_BLOCKING)
- hw_ctx_size += sizeof(struct srcu_struct);
-
- return hw_ctx_size;
-}
-
static struct blk_mq_hw_ctx *blk_mq_alloc_and_init_hctx(
struct blk_mq_tag_set *set, struct request_queue *q,
int hctx_idx, int node)
{
struct blk_mq_hw_ctx *hctx;

- hctx = kzalloc_node(blk_mq_hw_ctx_size(set),
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY,
- node);
+ hctx = blk_mq_alloc_hctx(q, set, node);
if (!hctx)
- return NULL;
-
- if (!zalloc_cpumask_var_node(&hctx->cpumask,
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY,
- node)) {
- kfree(hctx);
- return NULL;
- }
-
- atomic_set(&hctx->nr_active, 0);
- hctx->numa_node = node;
- hctx->queue_num = hctx_idx;
+ goto fail;

- if (blk_mq_init_hctx(q, set, hctx, hctx_idx)) {
- free_cpumask_var(hctx->cpumask);
- kfree(hctx);
- return NULL;
- }
- blk_mq_hctx_kobj_init(hctx);
+ if (blk_mq_init_hctx(q, set, hctx, hctx_idx))
+ goto free_hctx;

return hctx;
+
+ free_hctx:
+ kobject_put(&hctx->kobj);
+ fail:
+ return NULL;
}

static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set,
--
2.20.1