From: Nilay Shroff Date: Thu, 13 Nov 2025 08:58:19 +0000 (+0530) Subject: block: move elevator tags into struct elevator_resources X-Git-Tag: v6.19-rc1~168^2~48^2~3 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=04728ce90966c54417fd8120a3820104d18ba68d;p=thirdparty%2Fkernel%2Flinux.git block: move elevator tags into struct elevator_resources This patch introduces a new structure, struct elevator_resources, to group together all elevator-related resources that share the same lifetime. As a first step, this change moves the elevator tag pointer from struct elv_change_ctx into the new struct elevator_resources. Additionally, rename blk_mq_alloc_sched_tags_batch() and blk_mq_free_sched_tags_batch() to blk_mq_alloc_sched_res_batch() and blk_mq_free_sched_res_batch(), respectively. Introduce two new wrapper helpers, blk_mq_alloc_sched_res() and blk_mq_free_sched_res(), around blk_mq_alloc_sched_tags() and blk_mq_free_sched_tags(). These changes pave the way for consolidating the allocation and freeing of elevator-specific resources into common helper functions. This refactoring improves encapsulation and prepares the code for future extensions, allowing additional elevator-specific data to be added to struct elevator_resources without cluttering struct elv_change_ctx. Subsequent patches will extend struct elevator_resources to include other elevator-related data. Reviewed-by: Ming Lei Reviewed-by: Yu Kuai Signed-off-by: Nilay Shroff Signed-off-by: Jens Axboe --- diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 7ba285a7759b3..32ae57518298d 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -427,7 +427,16 @@ void blk_mq_free_sched_tags(struct elevator_tags *et, kfree(et); } -void blk_mq_free_sched_tags_batch(struct xarray *elv_tbl, +void blk_mq_free_sched_res(struct elevator_resources *res, + struct blk_mq_tag_set *set) +{ + if (res->et) { + blk_mq_free_sched_tags(res->et, set); + res->et = NULL; + } +} + +void blk_mq_free_sched_res_batch(struct xarray *elv_tbl, struct blk_mq_tag_set *set) { struct request_queue *q; @@ -445,12 +454,11 @@ void blk_mq_free_sched_tags_batch(struct xarray *elv_tbl, */ if (q->elevator) { ctx = xa_load(elv_tbl, q->id); - if (!ctx || !ctx->et) { + if (!ctx) { WARN_ON_ONCE(1); continue; } - blk_mq_free_sched_tags(ctx->et, set); - ctx->et = NULL; + blk_mq_free_sched_res(&ctx->res, set); } } } @@ -531,12 +539,24 @@ out: return NULL; } -int blk_mq_alloc_sched_tags_batch(struct xarray *elv_tbl, +int blk_mq_alloc_sched_res(struct request_queue *q, + struct elevator_resources *res, unsigned int nr_hw_queues) +{ + struct blk_mq_tag_set *set = q->tag_set; + + res->et = blk_mq_alloc_sched_tags(set, nr_hw_queues, + blk_mq_default_nr_requests(set)); + if (!res->et) + return -ENOMEM; + + return 0; +} + +int blk_mq_alloc_sched_res_batch(struct xarray *elv_tbl, struct blk_mq_tag_set *set, unsigned int nr_hw_queues) { struct elv_change_ctx *ctx; struct request_queue *q; - struct elevator_tags *et; int ret = -ENOMEM; lockdep_assert_held_write(&set->update_nr_hwq_lock); @@ -556,11 +576,10 @@ int blk_mq_alloc_sched_tags_batch(struct xarray *elv_tbl, goto out_unwind; } - ctx->et = blk_mq_alloc_sched_tags(set, nr_hw_queues, - blk_mq_default_nr_requests(set)); - if (!ctx->et) + ret = blk_mq_alloc_sched_res(q, &ctx->res, + nr_hw_queues); + if (ret) goto out_unwind; - } } return 0; @@ -568,10 +587,8 @@ out_unwind: list_for_each_entry_continue_reverse(q, &set->tag_list, tag_set_list) { if (q->elevator) { ctx = xa_load(elv_tbl, q->id); - if (ctx && ctx->et) { - blk_mq_free_sched_tags(ctx->et, set); - ctx->et = NULL; - } + if (ctx) + blk_mq_free_sched_res(&ctx->res, set); } } return ret; @@ -579,9 +596,10 @@ out_unwind: /* caller must have a reference to @e, will grab another one if successful */ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e, - struct elevator_tags *et) + struct elevator_resources *res) { unsigned int flags = q->tag_set->flags; + struct elevator_tags *et = res->et; struct blk_mq_hw_ctx *hctx; struct elevator_queue *eq; unsigned long i; diff --git a/block/blk-mq-sched.h b/block/blk-mq-sched.h index 2fddbc91a2359..1f8e58dd4b497 100644 --- a/block/blk-mq-sched.h +++ b/block/blk-mq-sched.h @@ -19,20 +19,24 @@ void __blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx); void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx); int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e, - struct elevator_tags *et); + struct elevator_resources *res); void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e); void blk_mq_sched_free_rqs(struct request_queue *q); struct elevator_tags *blk_mq_alloc_sched_tags(struct blk_mq_tag_set *set, unsigned int nr_hw_queues, unsigned int nr_requests); -int blk_mq_alloc_sched_tags_batch(struct xarray *et_table, +int blk_mq_alloc_sched_res(struct request_queue *q, + struct elevator_resources *res, unsigned int nr_hw_queues); +int blk_mq_alloc_sched_res_batch(struct xarray *elv_tbl, struct blk_mq_tag_set *set, unsigned int nr_hw_queues); int blk_mq_alloc_sched_ctx_batch(struct xarray *elv_tbl, struct blk_mq_tag_set *set); void blk_mq_free_sched_ctx_batch(struct xarray *elv_tbl); void blk_mq_free_sched_tags(struct elevator_tags *et, struct blk_mq_tag_set *set); -void blk_mq_free_sched_tags_batch(struct xarray *et_table, +void blk_mq_free_sched_res(struct elevator_resources *res, + struct blk_mq_tag_set *set); +void blk_mq_free_sched_res_batch(struct xarray *et_table, struct blk_mq_tag_set *set); static inline void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx) diff --git a/block/blk-mq.c b/block/blk-mq.c index 04c6356f0eb24..0d38daaa4705c 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -5072,7 +5072,7 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, if (blk_mq_alloc_sched_ctx_batch(&elv_tbl, set) < 0) goto out_free_ctx; - if (blk_mq_alloc_sched_tags_batch(&elv_tbl, set, nr_hw_queues) < 0) + if (blk_mq_alloc_sched_res_batch(&elv_tbl, set, nr_hw_queues) < 0) goto out_free_ctx; list_for_each_entry(q, &set->tag_list, tag_set_list) { diff --git a/block/elevator.c b/block/elevator.c index cd7bdff205c8c..cbec292a4af5b 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -580,7 +580,7 @@ static int elevator_switch(struct request_queue *q, struct elv_change_ctx *ctx) } if (new_e) { - ret = blk_mq_init_sched(q, new_e, ctx->et); + ret = blk_mq_init_sched(q, new_e, &ctx->res); if (ret) goto out_unfreeze; ctx->new = q->elevator; @@ -604,7 +604,8 @@ out_unfreeze: return ret; } -static void elv_exit_and_release(struct request_queue *q) +static void elv_exit_and_release(struct elv_change_ctx *ctx, + struct request_queue *q) { struct elevator_queue *e; unsigned memflags; @@ -616,7 +617,7 @@ static void elv_exit_and_release(struct request_queue *q) mutex_unlock(&q->elevator_lock); blk_mq_unfreeze_queue(q, memflags); if (e) { - blk_mq_free_sched_tags(e->et, q->tag_set); + blk_mq_free_sched_res(&ctx->res, q->tag_set); kobject_put(&e->kobj); } } @@ -627,11 +628,12 @@ static int elevator_change_done(struct request_queue *q, int ret = 0; if (ctx->old) { + struct elevator_resources res = {.et = ctx->old->et}; bool enable_wbt = test_bit(ELEVATOR_FLAG_ENABLE_WBT_ON_EXIT, &ctx->old->flags); elv_unregister_queue(q, ctx->old); - blk_mq_free_sched_tags(ctx->old->et, q->tag_set); + blk_mq_free_sched_res(&res, q->tag_set); kobject_put(&ctx->old->kobj); if (enable_wbt) wbt_enable_default(q->disk); @@ -639,7 +641,7 @@ static int elevator_change_done(struct request_queue *q, if (ctx->new) { ret = elv_register_queue(q, ctx->new, !ctx->no_uevent); if (ret) - elv_exit_and_release(q); + elv_exit_and_release(ctx, q); } return ret; } @@ -656,10 +658,9 @@ static int elevator_change(struct request_queue *q, struct elv_change_ctx *ctx) lockdep_assert_held(&set->update_nr_hwq_lock); if (strncmp(ctx->name, "none", 4)) { - ctx->et = blk_mq_alloc_sched_tags(set, set->nr_hw_queues, - blk_mq_default_nr_requests(set)); - if (!ctx->et) - return -ENOMEM; + ret = blk_mq_alloc_sched_res(q, &ctx->res, set->nr_hw_queues); + if (ret) + return ret; } memflags = blk_mq_freeze_queue(q); @@ -681,10 +682,10 @@ static int elevator_change(struct request_queue *q, struct elv_change_ctx *ctx) if (!ret) ret = elevator_change_done(q, ctx); /* - * Free sched tags if it's allocated but we couldn't switch elevator. + * Free sched resource if it's allocated but we couldn't switch elevator. */ - if (ctx->et && !ctx->new) - blk_mq_free_sched_tags(ctx->et, set); + if (!ctx->new) + blk_mq_free_sched_res(&ctx->res, set); return ret; } @@ -711,10 +712,10 @@ void elv_update_nr_hw_queues(struct request_queue *q, if (!ret) WARN_ON_ONCE(elevator_change_done(q, ctx)); /* - * Free sched tags if it's allocated but we couldn't switch elevator. + * Free sched resource if it's allocated but we couldn't switch elevator. */ - if (ctx->et && !ctx->new) - blk_mq_free_sched_tags(ctx->et, set); + if (!ctx->new) + blk_mq_free_sched_res(&ctx->res, set); } /* diff --git a/block/elevator.h b/block/elevator.h index bad43182361e5..621a63597249e 100644 --- a/block/elevator.h +++ b/block/elevator.h @@ -32,6 +32,11 @@ struct elevator_tags { struct blk_mq_tags *tags[]; }; +struct elevator_resources { + /* holds elevator tags */ + struct elevator_tags *et; +}; + /* Holding context data for changing elevator */ struct elv_change_ctx { const char *name; @@ -43,8 +48,8 @@ struct elv_change_ctx { struct elevator_queue *new; /* store elevator type */ struct elevator_type *type; - /* holds sched tags data */ - struct elevator_tags *et; + /* store elevator resources */ + struct elevator_resources res; }; struct elevator_mq_ops {