On 3/31/19 11:09 AM, Ming Lei wrote:
> This patch re-organizes blk_mq_exit_hctx() into two parts, and
> one part is for exit hctx, and another part is for free hw queue.
>
> No function change, just prepare for fixing hctx lifetime issue.
>
> Cc: James Smart <james.smart@xxxxxxxxxxxx>
> Cc: Bart Van Assche <bart.vanassche@xxxxxxx>
> Cc: linux-scsi@xxxxxxxxxxxxxxx,
> Cc: Martin K . Petersen <martin.petersen@xxxxxxxxxx>,
> Cc: Christoph Hellwig <hch@xxxxxx>,
> Cc: James E . J . Bottomley <jejb@xxxxxxxxxxxxxxxxxx>,
> Cc: jianchao wang <jianchao.w.wang@xxxxxxxxxx>
> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
> ---
> block/blk-mq.c | 16 +++++++++++-----
> 1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 70b210a308c4..53265ce45238 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -2229,6 +2229,16 @@ static void blk_mq_remove_cpuhp(struct blk_mq_hw_ctx *hctx)
> &hctx->cpuhp_dead);
> }
>
> +static void blk_mq_free_hctx(struct request_queue *q,
> + struct blk_mq_hw_ctx *hctx)
> +{
> + if (hctx->flags & BLK_MQ_F_BLOCKING)
> + cleanup_srcu_struct(hctx->srcu);
> +
> + blk_free_flush_queue(hctx->fq);
> + sbitmap_free(&hctx->ctx_map);
> +}
> +
> /* hctx->ctxs will be freed in queue's release handler */
> static void blk_mq_exit_hctx(struct request_queue *q,
> struct blk_mq_tag_set *set,
> @@ -2243,12 +2253,7 @@ static void blk_mq_exit_hctx(struct request_queue *q,
> if (set->ops->exit_hctx)
> set->ops->exit_hctx(hctx, hctx_idx);
>
> - if (hctx->flags & BLK_MQ_F_BLOCKING)
> - cleanup_srcu_struct(hctx->srcu);
> -
> blk_mq_remove_cpuhp(hctx);
> - blk_free_flush_queue(hctx->fq);
> - sbitmap_free(&hctx->ctx_map);
> }
>
> static void blk_mq_exit_hw_queues(struct request_queue *q,
> @@ -2262,6 +2267,7 @@ static void blk_mq_exit_hw_queues(struct request_queue *q,
> break;
> blk_mq_debugfs_unregister_hctx(hctx);
> blk_mq_exit_hctx(q, set, hctx, i);
> + blk_mq_free_hctx(q, hctx);
Assuming if this direction is still followed, how about blk_mq_realloc_hw_ctxs()
which is another caller of blk_mq_exit_hctx(), while part of blk_mq_exit_hctx()
is extracted and encapsulated into blk_mq_free_hctx()?
Additional blk_mq_free_hctx() is missing?
Dongli Zhang
> }
> }
>
>
