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d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=SADjSKEOkix4t8p9x6JY890dWdHLGsY9Rc7Lg6faQoU=; b=dvYTd1y0T5bHako3qX5y0bER4y2rL5k7ZtFDWTjDabekNZtyp0ZWH6itEgas2htxEA rkwTfM15axoiIjMU4dTvbLB0FVb3gJn+cB3/9na4uLeXiqSc472HKa7wEPAmCxzhW9Di 7YgXQVAwB7wdPyzbKH+VIkg0o6zvbDdm9Elw0Rtv2Lj85iejEn8BwrkL3d+NlBWN1k9Z IlypKwuUTNH+a6/dNJ1Skr9g4/ObRbBWVIvOnXR5GV4TeZN7ln7cZqp4sxmLzEXdD4kO SgxUm+pLsrkZn5HskVKmBoYbQwfKIq1hvAJxE7hgWabjGoyLUN9uSSJtNUeGbM4NigZe CaMg== X-Gm-Message-State: AOAM533wLiWnzzQYNZY0IJeMR1EQG+1+wWIPtcLt1MrsK9Re1mfsFu24 vHqlu3NdjyFHOEXfy794NgK8qWINjzicgw== X-Google-Smtp-Source: ABdhPJy7GZTEmdCMo498WUqWo9a2uGPWdWpqsedqeFm0EtTYld1vhYQOY8G7RBbK3kSdSt6fd4aawQ== X-Received: by 2002:a37:7b41:: with SMTP id w62mr195775qkc.256.1615909051073; Tue, 16 Mar 2021 08:37:31 -0700 (PDT) From: Dan Schatzberg Cc: Jens Axboe , Tejun Heo , Zefan Li , Johannes Weiner , Andrew Morton , Michal Hocko , Vladimir Davydov , Hugh Dickins , Shakeel Butt , Roman Gushchin , Muchun Song , Alex Shi , Alexander Duyck , Chris Down , Yafang Shao , Wei Yang , linux-block@vger.kernel.org (open list:BLOCK LAYER), linux-kernel@vger.kernel.org (open list), cgroups@vger.kernel.org (open list:CONTROL GROUP (CGROUP)), linux-mm@kvack.org (open list:MEMORY MANAGEMENT) Subject: [PATCH 3/3] loop: Charge i/o to mem and blk cg Date: Tue, 16 Mar 2021 08:36:52 -0700 Message-Id: <20210316153655.500806-4-schatzberg.dan@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210316153655.500806-1-schatzberg.dan@gmail.com> References: <20210316153655.500806-1-schatzberg.dan@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" The current code only associates with the existing blkcg when aio is used to access the backing file. This patch covers all types of i/o to the backing file and also associates the memcg so if the backing file is on tmpfs, memory is charged appropriately. This patch also exports cgroup_get_e_css and int_active_memcg so it can be used by the loop module. Signed-off-by: Dan Schatzberg Acked-by: Johannes Weiner --- drivers/block/loop.c | 61 +++++++++++++++++++++++++------------- drivers/block/loop.h | 3 +- include/linux/memcontrol.h | 11 +++++++ kernel/cgroup/cgroup.c | 1 + mm/memcontrol.c | 1 + 5 files changed, 56 insertions(+), 21 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 5c080af73caa..6cf3086a2e75 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -77,6 +77,7 @@ #include #include #include +#include =20 #include "loop.h" =20 @@ -515,8 +516,6 @@ static void lo_rw_aio_complete(struct kiocb *iocb, long= ret, long ret2) { struct loop_cmd *cmd =3D container_of(iocb, struct loop_cmd, iocb); =20 - if (cmd->css) - css_put(cmd->css); cmd->ret =3D ret; lo_rw_aio_do_completion(cmd); } @@ -577,8 +576,6 @@ static int lo_rw_aio(struct loop_device *lo, struct loo= p_cmd *cmd, cmd->iocb.ki_complete =3D lo_rw_aio_complete; cmd->iocb.ki_flags =3D IOCB_DIRECT; cmd->iocb.ki_ioprio =3D IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0); - if (cmd->css) - kthread_associate_blkcg(cmd->css); =20 if (rw =3D=3D WRITE) ret =3D call_write_iter(file, &cmd->iocb, &iter); @@ -586,7 +583,6 @@ static int lo_rw_aio(struct loop_device *lo, struct loo= p_cmd *cmd, ret =3D call_read_iter(file, &cmd->iocb, &iter); =20 lo_rw_aio_do_completion(cmd); - kthread_associate_blkcg(NULL); =20 if (ret !=3D -EIOCBQUEUED) cmd->iocb.ki_complete(&cmd->iocb, ret, 0); @@ -927,7 +923,7 @@ struct loop_worker { struct list_head cmd_list; struct list_head idle_list; struct loop_device *lo; - struct cgroup_subsys_state *css; + struct cgroup_subsys_state *blkcg_css; unsigned long last_ran_at; }; =20 @@ -944,7 +940,7 @@ static void loop_queue_work(struct loop_device *lo, str= uct loop_cmd *cmd) =20 spin_lock_irq(&lo->lo_work_lock); =20 - if (!cmd->css) + if (!cmd->blkcg_css) goto queue_work; =20 node =3D &lo->worker_tree.rb_node; @@ -952,10 +948,10 @@ static void loop_queue_work(struct loop_device *lo, s= truct loop_cmd *cmd) while (*node) { parent =3D *node; cur_worker =3D container_of(*node, struct loop_worker, rb_node); - if (cur_worker->css =3D=3D cmd->css) { + if (cur_worker->blkcg_css =3D=3D cmd->blkcg_css) { worker =3D cur_worker; break; - } else if ((long)cur_worker->css < (long)cmd->css) { + } else if ((long)cur_worker->blkcg_css < (long)cmd->blkcg_css) { node =3D &(*node)->rb_left; } else { node =3D &(*node)->rb_right; @@ -967,13 +963,18 @@ static void loop_queue_work(struct loop_device *lo, s= truct loop_cmd *cmd) worker =3D kzalloc(sizeof(struct loop_worker), GFP_NOWAIT | __GFP_NOWARN); /* * In the event we cannot allocate a worker, just queue on the - * rootcg worker + * rootcg worker and issue the I/O as the rootcg */ - if (!worker) + if (!worker) { + cmd->blkcg_css =3D NULL; + if (cmd->memcg_css) + css_put(cmd->memcg_css); + cmd->memcg_css =3D NULL; goto queue_work; + } =20 - worker->css =3D cmd->css; - css_get(worker->css); + worker->blkcg_css =3D cmd->blkcg_css; + css_get(worker->blkcg_css); INIT_WORK(&worker->work, loop_workfn); INIT_LIST_HEAD(&worker->cmd_list); INIT_LIST_HEAD(&worker->idle_list); @@ -1297,7 +1298,7 @@ static int __loop_clr_fd(struct loop_device *lo, bool= release) idle_list) { list_del(&worker->idle_list); rb_erase(&worker->rb_node, &lo->worker_tree); - css_put(worker->css); + css_put(worker->blkcg_css); kfree(worker); } spin_unlock_irq(&lo->lo_work_lock); @@ -2102,13 +2103,18 @@ static blk_status_t loop_queue_rq(struct blk_mq_hw_= ctx *hctx, } =20 /* always use the first bio's css */ + cmd->blkcg_css =3D NULL; + cmd->memcg_css =3D NULL; #ifdef CONFIG_BLK_CGROUP - if (cmd->use_aio && rq->bio && rq->bio->bi_blkg) { - cmd->css =3D &bio_blkcg(rq->bio)->css; - css_get(cmd->css); - } else + if (rq->bio && rq->bio->bi_blkg) { + cmd->blkcg_css =3D &bio_blkcg(rq->bio)->css; +#ifdef CONFIG_MEMCG + cmd->memcg_css =3D + cgroup_get_e_css(cmd->blkcg_css->cgroup, + &memory_cgrp_subsys); +#endif + } #endif - cmd->css =3D NULL; loop_queue_work(lo, cmd); =20 return BLK_STS_OK; @@ -2120,13 +2126,28 @@ static void loop_handle_cmd(struct loop_cmd *cmd) const bool write =3D op_is_write(req_op(rq)); struct loop_device *lo =3D rq->q->queuedata; int ret =3D 0; + struct mem_cgroup *old_memcg =3D NULL; =20 if (write && (lo->lo_flags & LO_FLAGS_READ_ONLY)) { ret =3D -EIO; goto failed; } =20 + if (cmd->blkcg_css) + kthread_associate_blkcg(cmd->blkcg_css); + if (cmd->memcg_css) + old_memcg =3D set_active_memcg( + mem_cgroup_from_css(cmd->memcg_css)); + ret =3D do_req_filebacked(lo, rq); + + if (cmd->blkcg_css) + kthread_associate_blkcg(NULL); + + if (cmd->memcg_css) { + set_active_memcg(old_memcg); + css_put(cmd->memcg_css); + } failed: /* complete non-aio request */ if (!cmd->use_aio || ret) { @@ -2205,7 +2226,7 @@ static void loop_free_idle_workers(struct timer_list = *timer) break; list_del(&worker->idle_list); rb_erase(&worker->rb_node, &lo->worker_tree); - css_put(worker->css); + css_put(worker->blkcg_css); kfree(worker); } if (!list_empty(&lo->idle_worker_list)) diff --git a/drivers/block/loop.h b/drivers/block/loop.h index 9289c1cd6374..cd24a81e00e6 100644 --- a/drivers/block/loop.h +++ b/drivers/block/loop.h @@ -76,7 +76,8 @@ struct loop_cmd { long ret; struct kiocb iocb; struct bio_vec *bvec; - struct cgroup_subsys_state *css; + struct cgroup_subsys_state *blkcg_css; + struct cgroup_subsys_state *memcg_css; }; =20 /* Support for loadable transfer modules */ diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 0c04d39a7967..fd5dd961d01f 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1187,6 +1187,17 @@ static inline struct mem_cgroup *get_mem_cgroup_from= _mm(struct mm_struct *mm) return NULL; } =20 +static inline struct mem_cgroup *get_mem_cgroup_from_page(struct page *pag= e) +{ + return NULL; +} + +static inline +struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css) +{ + return NULL; +} + static inline void mem_cgroup_put(struct mem_cgroup *memcg) { } diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 9153b20e5cc6..94c88f7221c5 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -577,6 +577,7 @@ struct cgroup_subsys_state *cgroup_get_e_css(struct cgr= oup *cgrp, rcu_read_unlock(); return css; } +EXPORT_SYMBOL_GPL(cgroup_get_e_css); =20 static void cgroup_get_live(struct cgroup *cgrp) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9a1b23ed3412..f05501669e29 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -78,6 +78,7 @@ struct mem_cgroup *root_mem_cgroup __read_mostly; =20 /* Active memory cgroup to use from an interrupt context */ DEFINE_PER_CPU(struct mem_cgroup *, int_active_memcg); +EXPORT_PER_CPU_SYMBOL_GPL(int_active_memcg); =20 /* Socket memory accounting disabled? */ static bool cgroup_memory_nosocket; --=20 2.30.2