From 6c8b232efea1ad3d263ff8b9c16b7e8767a77488 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Wed, 22 Feb 2017 18:14:01 +0800 Subject: [PATCH] blk-mq: make lifetime consistent between hctx and its kobject This patch removes kobject_put() over hctx in __blk_mq_unregister_dev(), and trys to keep lifetime consistent between hctx and hctx's kobject. Now blk_mq_sysfs_register() and blk_mq_sysfs_unregister() become totally symmetrical, and kobject's refcounter drops to zero just when the hctx is freed. Signed-off-by: Ming Lei Tested-by: Peter Zijlstra (Intel) Signed-off-by: Jens Axboe --- block/blk-mq-sysfs.c | 15 ++++++++++----- block/blk-mq.c | 5 +---- 2 files changed, 11 insertions(+), 9 deletions(-) diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c index 77fb238af2be..cb19ec16a7fc 100644 --- a/block/blk-mq-sysfs.c +++ b/block/blk-mq-sysfs.c @@ -17,6 +17,14 @@ static void blk_mq_sysfs_release(struct kobject *kobj) { } +static void blk_mq_hw_sysfs_release(struct kobject *kobj) +{ + struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx, + kobj); + kfree(hctx->ctxs); + kfree(hctx); +} + struct blk_mq_ctx_sysfs_entry { struct attribute attr; ssize_t (*show)(struct blk_mq_ctx *, char *); @@ -200,7 +208,7 @@ static struct kobj_type blk_mq_ctx_ktype = { static struct kobj_type blk_mq_hw_ktype = { .sysfs_ops = &blk_mq_hw_sysfs_ops, .default_attrs = default_hw_ctx_attrs, - .release = blk_mq_sysfs_release, + .release = blk_mq_hw_sysfs_release, }; static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx) @@ -244,12 +252,9 @@ static void __blk_mq_unregister_dev(struct device *dev, struct request_queue *q) struct blk_mq_hw_ctx *hctx; int i; - queue_for_each_hw_ctx(q, hctx, i) { + queue_for_each_hw_ctx(q, hctx, i) blk_mq_unregister_hctx(hctx); - kobject_put(&hctx->kobj); - } - blk_mq_debugfs_unregister_hctxs(q); kobject_uevent(&q->mq_kobj, KOBJ_REMOVE); diff --git a/block/blk-mq.c b/block/blk-mq.c index b985c236f50f..f70595e5fb86 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2256,8 +2256,7 @@ void blk_mq_release(struct request_queue *q) queue_for_each_hw_ctx(q, hctx, i) { if (!hctx) continue; - kfree(hctx->ctxs); - kfree(hctx); + kobject_put(&hctx->kobj); } q->mq_map = NULL; @@ -2336,8 +2335,6 @@ static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, blk_mq_exit_hctx(q, set, hctx, j); free_cpumask_var(hctx->cpumask); kobject_put(&hctx->kobj); - kfree(hctx->ctxs); - kfree(hctx); hctxs[j] = NULL; }