From patchwork Mon Apr 20 22:39:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Schatzberg X-Patchwork-Id: 11500031 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 36EC71392 for ; Mon, 20 Apr 2020 22:41:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DBB2B20B1F for ; Mon, 20 Apr 2020 22:41:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="L9z7d6El" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DBB2B20B1F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 094B68E0007; Mon, 20 Apr 2020 18:41:32 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 045A58E0003; Mon, 20 Apr 2020 18:41:32 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E9C618E0007; Mon, 20 Apr 2020 18:41:31 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0225.hostedemail.com [216.40.44.225]) by kanga.kvack.org (Postfix) with ESMTP id D398E8E0003 for ; Mon, 20 Apr 2020 18:41:31 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 9CD88824556B for ; Mon, 20 Apr 2020 22:41:31 +0000 (UTC) X-FDA: 76729706382.21.list22_477fad485a548 X-Spam-Summary: 2,0,0,6694f368f4970621,d41d8cd98f00b204,schatzberg.dan@gmail.com,,RULES_HIT:4:41:355:379:387:541:800:960:966:968:973:988:989:1260:1311:1314:1345:1359:1437:1515:1605:1730:1747:1777:1792:2194:2196:2198:2199:2200:2201:2393:2553:2559:2562:2637:2691:2693:2731:2918:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3872:3874:4250:4321:4384:4385:4395:4605:5007:6117:6119:6121:6261:6653:6742:6743:7514:8603:9010:9121:9413:9707:10004:11026:11473:11658:11914:12043:12291:12294:12296:12297:12438:12517:12519:12555:12683:12895:12986:13161:13184:13229:13868:13894:14096:14394:14687:14877:21433:21444:21451:21627:21666:21740:21983:21987:21990:30045:30054:30055:30090,0,RBL:209.85.219.65:@gmail.com:.lbl8.mailshell.net-66.100.201.100 62.18.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: list22_477fad485a548 X-Filterd-Recvd-Size: 15333 Received: from mail-qv1-f65.google.com (mail-qv1-f65.google.com [209.85.219.65]) by imf43.hostedemail.com (Postfix) with ESMTP for ; Mon, 20 Apr 2020 22:41:31 +0000 (UTC) Received: by mail-qv1-f65.google.com with SMTP id fb4so5619289qvb.7 for ; Mon, 20 Apr 2020 15:41:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=I53GuE/PpryNkjZAMmbvbjvTLp76oWX+vv7/Vav/aVI=; b=L9z7d6ElJQd/6gEEUGAg434Q0L+P99t4FngUseYUNBcQKomHG5udaf7w4S8UU/g9U9 IO3s8UdjtJ99I9jbpGht9XifOB7/ANCNaq8yRr4kbnbH5wR/amOnD6C1Phei1GWu1Plf z4SkSoysYKSbcyXiTsmb4j/gyGzf/ARtz+V2Pkpyow3YujXb9WHP/bGHHZFfX7Tia5sR JuYrU+qN3HErhDx/9qYUqMnuf5GvCIursi4MK9Ypm0hUWLnCw91Dxkb9cGfO3ASHrcv6 sLqteZ/a7uJgVauXLGR16sSVFG7Q78g+etC3CT/o/IvN6SLsXUoGv6IXn9NXeHPPvwFa AiTQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; 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=I53GuE/PpryNkjZAMmbvbjvTLp76oWX+vv7/Vav/aVI=; b=RiJ4BkOnndRMcRx0bbR0fRqtDZ1pas9wmf1t//8ilQGGtAt233M3GTysy1whjR6tAk 9P54O/5u/ITffYZKekLE5lux6clf+ymuCNC8xmf8QrfOHbjgM5OqBjN4yG4swbN6sDjB E/7O2rAAazCsBuXJ2AG5fHQYjbDGfmWMbtVJCPKlrja0OIbi0j96Bc4N675ADOYUUa8C 8AR9UL3qtn5C7QHEdTG2YgNiN9c0m0+/G0igc8HnwTeq2eK2ZpRWf/wa3BFgIZRbJUnu ++PE5J1dd0Jqz/webNZ6CqfnRgXVMvlMvQwoJsSSkbRGWeTCupwnU5tfUyyFSMDNXWGr bVNg== X-Gm-Message-State: AGi0PubbTdXhC/niuOeh2yWeM7sLzFwbEQ0LKthwrjEheBqMSVGFPDUF LOA1SY2icNaMntjWUUpJmxQ= X-Google-Smtp-Source: APiQypJNjAIXQw726NC6gLPclR5KgakscQJxzfArhJX+NkNQ9hVK+Q2rmE3PSI6OTj1ce/oUA+8dYQ== X-Received: by 2002:a0c:ed26:: with SMTP id u6mr17005587qvq.220.1587422490480; Mon, 20 Apr 2020 15:41:30 -0700 (PDT) Received: from dschatzberg-fedora-PC0Y6AEN.thefacebook.com ([2620:10d:c091:480::1:b0d9]) by smtp.gmail.com with ESMTPSA id j90sm511052qte.20.2020.04.20.15.41.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Apr 2020 15:41:29 -0700 (PDT) From: Dan Schatzberg To: Cc: Dan Schatzberg , Jens Axboe , Alexander Viro , Jan Kara , Amir Goldstein , Tejun Heo , Li Zefan , Johannes Weiner , Michal Hocko , Vladimir Davydov , Andrew Morton , Hugh Dickins , Roman Gushchin , Shakeel Butt , Chris Down , Yang Shi , Ingo Molnar , "Peter Zijlstra (Intel)" , Mathieu Desnoyers , Thomas Gleixner , Andrea Arcangeli , linux-block@vger.kernel.org (open list:BLOCK LAYER), linux-kernel@vger.kernel.org (open list), linux-fsdevel@vger.kernel.org (open list:FILESYSTEMS (VFS and infrastructure)), cgroups@vger.kernel.org (open list:CONTROL GROUP (CGROUP)), linux-mm@kvack.org (open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)) Subject: [PATCH 1/4] loop: Use worker per cgroup instead of kworker Date: Mon, 20 Apr 2020 18:39:29 -0400 Message-Id: <20200420223936.6773-2-schatzberg.dan@gmail.com> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200420223936.6773-1-schatzberg.dan@gmail.com> References: <20200420223936.6773-1-schatzberg.dan@gmail.com> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Existing uses of loop device may have multiple cgroups reading/writing to the same device. Simply charging resources for I/O to the backing file could result in priority inversion where one cgroup gets synchronously blocked, holding up all other I/O to the loop device. In order to avoid this priority inversion, we use a single workqueue where each work item is a "struct loop_worker" which contains a queue of struct loop_cmds to issue. The loop device maintains a tree mapping blk css_id -> loop_worker. This allows each cgroup to independently make forward progress issuing I/O to the backing file. There is also a single queue for I/O associated with the rootcg which can be used in cases of extreme memory shortage where we cannot allocate a loop_worker. The locking for the tree and queues is fairly heavy handed - we acquire the per-loop-device spinlock any time either is accessed. The existing implementation serializes all I/O through a single thread anyways, so I don't believe this is any worse. Signed-off-by: Dan Schatzberg --- drivers/block/loop.c | 207 ++++++++++++++++++++++++++++++++++++------- drivers/block/loop.h | 11 ++- 2 files changed, 180 insertions(+), 38 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index da693e6a834e..3a109975d2df 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -70,7 +70,6 @@ #include #include #include -#include #include #include #include @@ -83,6 +82,8 @@ #include +#define LOOP_IDLE_WORKER_TIMEOUT (60 * HZ) + static DEFINE_IDR(loop_index_idr); static DEFINE_MUTEX(loop_ctl_mutex); @@ -778,12 +779,18 @@ static ssize_t loop_attr_backing_file_show(struct loop_device *lo, char *buf) { ssize_t ret; char *p = NULL; + struct file *filp = NULL; spin_lock_irq(&lo->lo_lock); if (lo->lo_backing_file) - p = file_path(lo->lo_backing_file, buf, PAGE_SIZE - 1); + filp = get_file(lo->lo_backing_file); spin_unlock_irq(&lo->lo_lock); + if (filp) { + p = file_path(filp, buf, PAGE_SIZE - 1); + fput(filp); + } + if (IS_ERR_OR_NULL(p)) ret = PTR_ERR(p); else { @@ -911,27 +918,83 @@ static void loop_config_discard(struct loop_device *lo) blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q); } -static void loop_unprepare_queue(struct loop_device *lo) -{ - kthread_flush_worker(&lo->worker); - kthread_stop(lo->worker_task); -} +struct loop_worker { + struct rb_node rb_node; + struct work_struct work; + struct list_head cmd_list; + struct list_head idle_list; + struct loop_device *lo; + struct cgroup_subsys_state *css; + unsigned long last_ran_at; +}; -static int loop_kthread_worker_fn(void *worker_ptr) -{ - current->flags |= PF_LESS_THROTTLE | PF_MEMALLOC_NOIO; - return kthread_worker_fn(worker_ptr); -} +static void loop_workfn(struct work_struct *work); +static void loop_rootcg_workfn(struct work_struct *work); +static void loop_free_idle_workers(struct timer_list *timer); -static int loop_prepare_queue(struct loop_device *lo) +static void loop_queue_work(struct loop_device *lo, struct loop_cmd *cmd) { - kthread_init_worker(&lo->worker); - lo->worker_task = kthread_run(loop_kthread_worker_fn, - &lo->worker, "loop%d", lo->lo_number); - if (IS_ERR(lo->worker_task)) - return -ENOMEM; - set_user_nice(lo->worker_task, MIN_NICE); - return 0; + struct rb_node **node = &(lo->worker_tree.rb_node), *parent = NULL; + struct loop_worker *cur_worker, *worker = NULL; + struct work_struct *work; + struct list_head *cmd_list; + + spin_lock_irq(&lo->lo_lock); + + if (!cmd->css) + goto queue_work; + + node = &lo->worker_tree.rb_node; + + while (*node) { + parent = *node; + cur_worker = container_of(*node, struct loop_worker, rb_node); + if (cur_worker->css == cmd->css) { + worker = cur_worker; + break; + } else if ((long)cur_worker->css < (long)cmd->css) { + node = &(*node)->rb_left; + } else { + node = &(*node)->rb_right; + } + } + if (worker) + goto queue_work; + + worker = kzalloc(sizeof(struct loop_worker), GFP_NOWAIT | __GFP_NOWARN); + /* + * In the event we cannot allocate a worker, just queue on the + * rootcg worker + */ + if (!worker) + goto queue_work; + + worker->css = cmd->css; + css_get(worker->css); + INIT_WORK(&worker->work, loop_workfn); + INIT_LIST_HEAD(&worker->cmd_list); + INIT_LIST_HEAD(&worker->idle_list); + worker->lo = lo; + rb_link_node(&worker->rb_node, parent, node); + rb_insert_color(&worker->rb_node, &lo->worker_tree); +queue_work: + if (worker) { + /* + * We need to remove from the idle list here while + * holding the lock so that the idle timer doesn't + * free the worker + */ + if (!list_empty(&worker->idle_list)) + list_del_init(&worker->idle_list); + work = &worker->work; + cmd_list = &worker->cmd_list; + } else { + work = &lo->rootcg_work; + cmd_list = &lo->rootcg_cmd_list; + } + list_add_tail(&cmd->list_entry, cmd_list); + queue_work(lo->workqueue, work); + spin_unlock_irq(&lo->lo_lock); } static void loop_update_rotational(struct loop_device *lo) @@ -1007,14 +1070,25 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, size = get_loop_size(lo, file); if ((loff_t)(sector_t)size != size) goto out_unlock; - error = loop_prepare_queue(lo); - if (error) + lo->workqueue = alloc_workqueue("loop%d", + WQ_UNBOUND | WQ_FREEZABLE | + WQ_MEM_RECLAIM, + lo->lo_number); + if (!lo->workqueue) { + error = -ENOMEM; goto out_unlock; + } error = 0; set_device_ro(bdev, (lo_flags & LO_FLAGS_READ_ONLY) != 0); + INIT_WORK(&lo->rootcg_work, loop_rootcg_workfn); + INIT_LIST_HEAD(&lo->rootcg_cmd_list); + INIT_LIST_HEAD(&lo->idle_worker_list); + lo->worker_tree = RB_ROOT; + timer_setup(&lo->timer, loop_free_idle_workers, + TIMER_DEFERRABLE); lo->use_dio = false; lo->lo_device = bdev; lo->lo_flags = lo_flags; @@ -1123,6 +1197,7 @@ static int __loop_clr_fd(struct loop_device *lo, bool release) int err = 0; bool partscan = false; int lo_number; + struct loop_worker *pos, *worker; mutex_lock(&loop_ctl_mutex); if (WARN_ON_ONCE(lo->lo_state != Lo_rundown)) { @@ -1140,8 +1215,17 @@ static int __loop_clr_fd(struct loop_device *lo, bool release) blk_mq_freeze_queue(lo->lo_queue); spin_lock_irq(&lo->lo_lock); + destroy_workqueue(lo->workqueue); lo->lo_backing_file = NULL; + list_for_each_entry_safe(worker, pos, &lo->idle_worker_list, + idle_list) { + list_del(&worker->idle_list); + rb_erase(&worker->rb_node, &lo->worker_tree); + css_put(worker->css); + kfree(worker); + } spin_unlock_irq(&lo->lo_lock); + del_timer_sync(&lo->timer); loop_release_xfer(lo); lo->transfer = NULL; @@ -1176,7 +1260,6 @@ static int __loop_clr_fd(struct loop_device *lo, bool release) partscan = lo->lo_flags & LO_FLAGS_PARTSCAN && bdev; lo_number = lo->lo_number; - loop_unprepare_queue(lo); out_unlock: mutex_unlock(&loop_ctl_mutex); if (partscan) { @@ -1954,7 +2037,7 @@ static blk_status_t loop_queue_rq(struct blk_mq_hw_ctx *hctx, } else #endif cmd->css = NULL; - kthread_queue_work(&lo->worker, &cmd->work); + loop_queue_work(lo, cmd); return BLK_STS_OK; } @@ -1983,26 +2066,82 @@ static void loop_handle_cmd(struct loop_cmd *cmd) } } -static void loop_queue_work(struct kthread_work *work) +static void loop_set_timer(struct loop_device *lo) +{ + timer_reduce(&lo->timer, jiffies + LOOP_IDLE_WORKER_TIMEOUT); +} + +static void loop_process_work(struct loop_worker *worker, + struct list_head *cmd_list, struct loop_device *lo) { - struct loop_cmd *cmd = - container_of(work, struct loop_cmd, work); + int orig_flags = current->flags; + struct loop_cmd *cmd; - loop_handle_cmd(cmd); + current->flags |= PF_LESS_THROTTLE | PF_MEMALLOC_NOIO; + spin_lock_irq(&lo->lo_lock); + while (!list_empty(cmd_list)) { + cmd = container_of( + cmd_list->next, struct loop_cmd, list_entry); + list_del(cmd_list->next); + spin_unlock_irq(&lo->lo_lock); + + loop_handle_cmd(cmd); + cond_resched(); + + spin_lock_irq(&lo->lo_lock); + } + + /* + * We only add to the idle list if there are no pending cmds + * *and* the worker will not run again which ensures that it + * is safe to free any worker on the idle list + */ + if (worker && !work_pending(&worker->work)) { + worker->last_ran_at = jiffies; + list_add_tail(&worker->idle_list, &lo->idle_worker_list); + loop_set_timer(lo); + } + spin_unlock_irq(&lo->lo_lock); + current->flags = orig_flags; } -static int loop_init_request(struct blk_mq_tag_set *set, struct request *rq, - unsigned int hctx_idx, unsigned int numa_node) +static void loop_workfn(struct work_struct *work) { - struct loop_cmd *cmd = blk_mq_rq_to_pdu(rq); + struct loop_worker *worker = + container_of(work, struct loop_worker, work); + loop_process_work(worker, &worker->cmd_list, worker->lo); +} - kthread_init_work(&cmd->work, loop_queue_work); - return 0; +static void loop_rootcg_workfn(struct work_struct *work) +{ + struct loop_device *lo = + container_of(work, struct loop_device, rootcg_work); + loop_process_work(NULL, &lo->rootcg_cmd_list, lo); +} + +static void loop_free_idle_workers(struct timer_list *timer) +{ + struct loop_device *lo = container_of(timer, struct loop_device, timer); + struct loop_worker *pos, *worker; + + spin_lock_irq(&lo->lo_lock); + list_for_each_entry_safe(worker, pos, &lo->idle_worker_list, + idle_list) { + if (time_is_after_jiffies(worker->last_ran_at + + LOOP_IDLE_WORKER_TIMEOUT)) + break; + list_del(&worker->idle_list); + rb_erase(&worker->rb_node, &lo->worker_tree); + css_put(worker->css); + kfree(worker); + } + if (!list_empty(&lo->idle_worker_list)) + loop_set_timer(lo); + spin_unlock_irq(&lo->lo_lock); } static const struct blk_mq_ops loop_mq_ops = { .queue_rq = loop_queue_rq, - .init_request = loop_init_request, .complete = lo_complete_rq, }; diff --git a/drivers/block/loop.h b/drivers/block/loop.h index af75a5ee4094..87fd0e372227 100644 --- a/drivers/block/loop.h +++ b/drivers/block/loop.h @@ -14,7 +14,6 @@ #include #include #include -#include #include /* Possible states of device */ @@ -54,8 +53,12 @@ struct loop_device { spinlock_t lo_lock; int lo_state; - struct kthread_worker worker; - struct task_struct *worker_task; + struct workqueue_struct *workqueue; + struct work_struct rootcg_work; + struct list_head rootcg_cmd_list; + struct list_head idle_worker_list; + struct rb_root worker_tree; + struct timer_list timer; bool use_dio; bool sysfs_inited; @@ -65,7 +68,7 @@ struct loop_device { }; struct loop_cmd { - struct kthread_work work; + struct list_head list_entry; bool use_aio; /* use AIO interface to handle I/O */ atomic_t ref; /* only for aio */ long ret; From patchwork Mon Apr 20 22:39:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Schatzberg X-Patchwork-Id: 11500037 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 36FB9112C for ; Mon, 20 Apr 2020 22:41:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DC63B206F9 for ; Mon, 20 Apr 2020 22:41:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="s0ppksDP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DC63B206F9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0E4D68E0008; Mon, 20 Apr 2020 18:41:40 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 0BA098E0003; Mon, 20 Apr 2020 18:41:40 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EE9E48E0008; Mon, 20 Apr 2020 18:41:39 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0222.hostedemail.com [216.40.44.222]) by kanga.kvack.org (Postfix) with ESMTP id D840B8E0003 for ; Mon, 20 Apr 2020 18:41:39 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 9F4E1181AEF2A for ; Mon, 20 Apr 2020 22:41:39 +0000 (UTC) X-FDA: 76729706718.16.rice10_48a56ffbff521 X-Spam-Summary: 2,0,0,c4d09c7044413fc3,d41d8cd98f00b204,schatzberg.dan@gmail.com,,RULES_HIT:1:2:41:69:355:379:387:541:800:960:973:981:988:989:1260:1311:1314:1345:1359:1437:1515:1605:1730:1747:1777:1792:1801:2194:2199:2393:2553:2559:2562:2693:2894:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3872:3874:4049:4250:4321:4605:5007:6119:6261:6653:6742:6743:7514:7875:7903:8603:9413:9592:10004:11026:11232:11473:11658:11914:12043:12114:12296:12297:12438:12517:12519:12555:12895:12986:13161:13227:13229:13894:14096:14394:14687:21433:21444:21450:21627:21666:21740:21809:21990:30054:30055:30070:30080:30090,0,RBL:209.85.160.193:@gmail.com:.lbl8.mailshell.net-62.50.0.100 66.100.201.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: rice10_48a56ffbff521 X-Filterd-Recvd-Size: 10227 Received: from mail-qt1-f193.google.com (mail-qt1-f193.google.com [209.85.160.193]) by imf32.hostedemail.com (Postfix) with ESMTP for ; Mon, 20 Apr 2020 22:41:39 +0000 (UTC) Received: by mail-qt1-f193.google.com with SMTP id w29so10103165qtv.3 for ; Mon, 20 Apr 2020 15:41:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=PF+r9U7T5dFzMfmZ2H0sB6HLsz2rHKKvLwEVcGuIpcE=; b=s0ppksDPgiSOKM/KyEDwVugxCmb68ObCnOTlITDua9AHhazdNHlaSsX/KW4jFbGBhM pvUIpAr0MRoq3iv+YMnxYsAhJT6r9WiVNjR/5WwnD91XtuI2M62sKocensWqKopi4kMe trU21vd4mymUKSAapwtiANNo7l8praDENDhXtymMn/IYpSm/ERxRn2Z8AZCkccuy9e3L 7061fVDHGmriR7TKsT/ISC3xfVKc6KQ2QcZnLMqhY9erQC0h5wlkNLyx4tvVsBsozLt3 D2VPllTthDJzXvx+fdkFFCeds2NiAWkwf0ix6m2soi2cino3ITqoi84RKQ+AJJd2eytV UMMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; 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=PF+r9U7T5dFzMfmZ2H0sB6HLsz2rHKKvLwEVcGuIpcE=; b=FGg4c/xhZMixAeodKa9qGslrw2NezYGc/Rc8sY9DDhUyjilaSSjkiItnK+5KnZjEHY h2BGyyRwT0d6aAvCA2Pu5nWulzxuOueasrK/bItpPD1er96iV3ZGqr7mS/WVXExKWaMi MLUKRK0lbijeu37MGm3nWInz7uovg1WpErcXrC4/Us0tgUnb5qmHsvpabtWSvPY4FY6H Rfy0Ug7oj9Y7EE6CkYzpVs/dhYLPpRrWmzMQxTe/yJSU6QPMCkrPsDm3diac/kJtd2KF VyT4/jAA4qJlvZZhcuAXQKUxRhYwc9R9rkJJTo1gwXnOmsEWWxuv071ox7RpN8CFzb31 LxyQ== X-Gm-Message-State: AGi0PuY1Oe6F3lXmF1Wnyy0vJjJ/pSAytXo11F0rybqoeklbkDSDmBce kCgmnpOJgwjMLqyYnmaEQFc= X-Google-Smtp-Source: APiQypJGk7yzl7B27FXZuzmRx3Qzwgn98bKgk5SustM+NXz9qsMst0hrcMBafzm+J+VhYleyAKcBCw== X-Received: by 2002:ac8:3025:: with SMTP id f34mr19014333qte.219.1587422497596; Mon, 20 Apr 2020 15:41:37 -0700 (PDT) Received: from dschatzberg-fedora-PC0Y6AEN.thefacebook.com ([2620:10d:c091:480::1:b0d9]) by smtp.gmail.com with ESMTPSA id j90sm511052qte.20.2020.04.20.15.41.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Apr 2020 15:41:36 -0700 (PDT) From: Dan Schatzberg To: Cc: Dan Schatzberg , Jens Axboe , Alexander Viro , Jan Kara , Amir Goldstein , Tejun Heo , Li Zefan , Johannes Weiner , Michal Hocko , Vladimir Davydov , Andrew Morton , Hugh Dickins , Roman Gushchin , Shakeel Butt , Chris Down , Yang Shi , Ingo Molnar , "Peter Zijlstra (Intel)" , Mathieu Desnoyers , "Kirill A. Shutemov" , Andrea Arcangeli , Thomas Gleixner , linux-block@vger.kernel.org (open list:BLOCK LAYER), linux-kernel@vger.kernel.org (open list), linux-fsdevel@vger.kernel.org (open list:FILESYSTEMS (VFS and infrastructure)), cgroups@vger.kernel.org (open list:CONTROL GROUP (CGROUP)), linux-mm@kvack.org (open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)) Subject: [PATCH 2/4] mm: support nesting memalloc_use_memcg() Date: Mon, 20 Apr 2020 18:39:30 -0400 Message-Id: <20200420223936.6773-3-schatzberg.dan@gmail.com> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200420223936.6773-1-schatzberg.dan@gmail.com> References: <20200420223936.6773-1-schatzberg.dan@gmail.com> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: The memalloc_use_memcg() function to override the default memcg accounting context currently doesn't nest. But the patches to make the loop driver cgroup-aware will end up nesting: [ 98.137605] alloc_page_buffers+0x210/0x288 [ 98.141799] __getblk_gfp+0x1d4/0x400 [ 98.145475] ext4_read_block_bitmap_nowait+0x148/0xbc8 [ 98.150628] ext4_mb_init_cache+0x25c/0x9b0 [ 98.154821] ext4_mb_init_group+0x270/0x390 [ 98.159014] ext4_mb_good_group+0x264/0x270 [ 98.163208] ext4_mb_regular_allocator+0x480/0x798 [ 98.168011] ext4_mb_new_blocks+0x958/0x10f8 [ 98.172294] ext4_ext_map_blocks+0xec8/0x1618 [ 98.176660] ext4_map_blocks+0x1b8/0x8a0 [ 98.180592] ext4_writepages+0x830/0xf10 [ 98.184523] do_writepages+0xb4/0x198 [ 98.188195] __filemap_fdatawrite_range+0x170/0x1c8 [ 98.193086] filemap_write_and_wait_range+0x40/0xb0 [ 98.197974] ext4_punch_hole+0x4a4/0x660 [ 98.201907] ext4_fallocate+0x294/0x1190 [ 98.205839] loop_process_work+0x690/0x1100 [ 98.210032] loop_workfn+0x2c/0x110 [ 98.213529] process_one_work+0x3e0/0x648 [ 98.217546] worker_thread+0x70/0x670 [ 98.221217] kthread+0x1b8/0x1c0 [ 98.224452] ret_from_fork+0x10/0x18 where loop_process_work() sets the memcg override to the memcg that submitted the IO request, and alloc_page_buffers() sets the override to the memcg that instantiated the cache page, which may differ. Make memalloc_use_memcg() return the old memcg and convert existing users to a stacking model. Delete the unused memalloc_unuse_memcg(). Signed-off-by: Dan Schatzberg Reviewed-by: Shakeel Butt Acked-by: Roman Gushchin --- fs/buffer.c | 6 +++--- fs/notify/fanotify/fanotify.c | 5 +++-- fs/notify/inotify/inotify_fsnotify.c | 5 +++-- include/linux/sched/mm.h | 28 +++++++++------------------- 4 files changed, 18 insertions(+), 26 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 599a0bf7257b..e39e05985323 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -851,13 +851,13 @@ struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, struct buffer_head *bh, *head; gfp_t gfp = GFP_NOFS | __GFP_ACCOUNT; long offset; - struct mem_cgroup *memcg; + struct mem_cgroup *memcg, *oldmemcg; if (retry) gfp |= __GFP_NOFAIL; memcg = get_mem_cgroup_from_page(page); - memalloc_use_memcg(memcg); + oldmemcg = memalloc_use_memcg(memcg); head = NULL; offset = PAGE_SIZE; @@ -876,7 +876,7 @@ struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, set_bh_page(bh, page, offset); } out: - memalloc_unuse_memcg(); + memalloc_use_memcg(oldmemcg); mem_cgroup_put(memcg); return head; /* diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 5435a40f82be..54c787cd6efb 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -353,6 +353,7 @@ struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, gfp_t gfp = GFP_KERNEL_ACCOUNT; struct inode *id = fanotify_fid_inode(inode, mask, data, data_type); const struct path *path = fsnotify_data_path(data, data_type); + struct mem_cgroup *oldmemcg; /* * For queues with unlimited length lost events are not expected and @@ -366,7 +367,7 @@ struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, gfp |= __GFP_RETRY_MAYFAIL; /* Whoever is interested in the event, pays for the allocation. */ - memalloc_use_memcg(group->memcg); + oldmemcg = memalloc_use_memcg(group->memcg); if (fanotify_is_perm_event(mask)) { struct fanotify_perm_event *pevent; @@ -451,7 +452,7 @@ struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, } } out: - memalloc_unuse_memcg(); + memalloc_use_memcg(oldmemcg); return event; } diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index 2ebc89047153..d27c6e83cea6 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -69,6 +69,7 @@ int inotify_handle_event(struct fsnotify_group *group, int ret; int len = 0; int alloc_len = sizeof(struct inotify_event_info); + struct mem_cgroup *oldmemcg; if (WARN_ON(fsnotify_iter_vfsmount_mark(iter_info))) return 0; @@ -93,9 +94,9 @@ int inotify_handle_event(struct fsnotify_group *group, * trigger OOM killer in the target monitoring memcg as it may have * security repercussion. */ - memalloc_use_memcg(group->memcg); + oldmemcg = memalloc_use_memcg(group->memcg); event = kmalloc(alloc_len, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); - memalloc_unuse_memcg(); + memalloc_use_memcg(oldmemcg); if (unlikely(!event)) { /* diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index c49257a3b510..95e8bfb0cab1 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -316,31 +316,21 @@ static inline void memalloc_nocma_restore(unsigned int flags) * __GFP_ACCOUNT allocations till the end of the scope will be charged to the * given memcg. * - * NOTE: This function is not nesting safe. + * NOTE: This function can nest. Users must save the return value and + * reset the previous value after their own charging scope is over */ -static inline void memalloc_use_memcg(struct mem_cgroup *memcg) +static inline struct mem_cgroup * +memalloc_use_memcg(struct mem_cgroup *memcg) { - WARN_ON_ONCE(current->active_memcg); + struct mem_cgroup *old = current->active_memcg; current->active_memcg = memcg; -} - -/** - * memalloc_unuse_memcg - Ends the remote memcg charging scope. - * - * This function marks the end of the remote memcg charging scope started by - * memalloc_use_memcg(). - */ -static inline void memalloc_unuse_memcg(void) -{ - current->active_memcg = NULL; + return old; } #else -static inline void memalloc_use_memcg(struct mem_cgroup *memcg) -{ -} - -static inline void memalloc_unuse_memcg(void) +static inline struct mem_cgroup * +memalloc_use_memcg(struct mem_cgroup *memcg) { + return NULL; } #endif From patchwork Mon Apr 20 22:39:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Schatzberg X-Patchwork-Id: 11500041 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9E7036CA for ; Mon, 20 Apr 2020 22:41:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6101420672 for ; Mon, 20 Apr 2020 22:41:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LBEn7bne" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6101420672 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 883128E0005; Mon, 20 Apr 2020 18:41:47 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 833178E0003; Mon, 20 Apr 2020 18:41:47 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 721FC8E0005; Mon, 20 Apr 2020 18:41:47 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0177.hostedemail.com [216.40.44.177]) by kanga.kvack.org (Postfix) with ESMTP id 59F518E0003 for ; Mon, 20 Apr 2020 18:41:47 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 18826181AEF2A for ; Mon, 20 Apr 2020 22:41:47 +0000 (UTC) X-FDA: 76729707054.06.fork42_49baf2ddd4413 X-Spam-Summary: 2,0,0,f03b10b9dfdf19f0,d41d8cd98f00b204,schatzberg.dan@gmail.com,,RULES_HIT:41:355:379:387:541:800:960:973:988:989:1260:1311:1314:1345:1359:1437:1515:1535:1542:1711:1730:1747:1777:1792:2198:2199:2393:2559:2562:2731:3138:3139:3140:3141:3142:3354:3865:3867:3870:3871:3872:3874:4117:4250:4321:4605:5007:6119:6261:6653:6742:6743:7514:7901:7903:9413:10004:11026:11658:11914:12043:12296:12297:12438:12517:12519:12555:12895:12986:13053:13894:14096:14181:14394:14687:14721:21324:21433:21444:21451:21627:21666:21740:21795:21990:30012:30051:30054:30055:30075:30090,0,RBL:209.85.222.193:@gmail.com:.lbl8.mailshell.net-66.100.201.100 62.18.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: fork42_49baf2ddd4413 X-Filterd-Recvd-Size: 6911 Received: from mail-qk1-f193.google.com (mail-qk1-f193.google.com [209.85.222.193]) by imf03.hostedemail.com (Postfix) with ESMTP for ; Mon, 20 Apr 2020 22:41:46 +0000 (UTC) Received: by mail-qk1-f193.google.com with SMTP id j4so12592874qkc.11 for ; Mon, 20 Apr 2020 15:41:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=1xs7a52HdDCbAExnqSe5+2K/TyJ01Rp0raQ7acG2FHw=; b=LBEn7bneTlbqWBhqE2IIOuFPDU45rQRp1EY5buf++UFJUWy3jsS+81KMlghgb3LFBk hFj25ZFBr8VBuLNn4PaIzXR1hBoyXf8+sEdvG48kqGl3lQQ2wjQlb/XInPNC+BtMbt2S WN3T3aPyHlIH8WHoKeIizh0txrP2MwcLxuNRjsv2l2Bm9nQJjVamOygS4H4jd96tmWun kUiUxVrStl8llq4Quf4MN3w6oZmW/F7Dv9Gd1sAAUUprqFBlUmSHZ8DXteIGwybfWzG6 TkMIZe/0wZgW4z3G5XJrnFbnOcP1/15w+yMkGWWmcmIjiaZEw0qijSD2sWEVZQg74bMm ezSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; 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=1xs7a52HdDCbAExnqSe5+2K/TyJ01Rp0raQ7acG2FHw=; b=nFhBAQ2Z1Vi8csZd9tYWz/ldHOd+4FfUh74VXdVtOO8VHfWeaIKFTjSCZ/vx8IZN3S unOpy6IkQ2ex0M1xmux6DdQXc0FN5NkGCpDnCf3b+9lPMXB7i+ski/yGEb42wuxJSwuC hyaTJ0M4xS35rReF8Gvld9NqvfvLD18Ipl7E6qca6BZPlXeu9TIJwqw1LX30mFfNYwSn FzbB05kEr68H2GIBHAdKkf0/My8dib4OeN4VHS1R5wcBAD9OuA+LEKTlma9oa2r0gjfv D/bpyw2rl+DUcJ4Vx9OZf7gX3DZrYTJAQEUuHw7P0cCgByKsA8IPS5ZM9+iTPPXazBTk yvjw== X-Gm-Message-State: AGi0PubUtU4z4zuCYEAPdLrRFjXJsasziwSD5pVBWEFfP+3ysxPhNMqp 4ehY7ecl6WHPbsWZUbAt6zc= X-Google-Smtp-Source: APiQypL4UcYluQEWwxN6yDbDlj/pGdI0PL/O26k1R1mC5DVwhSgdhKf4O8pmqQGMjlFBHeB5aBBAFA== X-Received: by 2002:a05:620a:2054:: with SMTP id d20mr17844738qka.496.1587422505955; Mon, 20 Apr 2020 15:41:45 -0700 (PDT) Received: from dschatzberg-fedora-PC0Y6AEN.thefacebook.com ([2620:10d:c091:480::1:b0d9]) by smtp.gmail.com with ESMTPSA id j90sm511052qte.20.2020.04.20.15.41.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Apr 2020 15:41:45 -0700 (PDT) From: Dan Schatzberg To: Cc: Dan Schatzberg , Johannes Weiner , Tejun Heo , Chris Down , Shakeel Butt , Jens Axboe , Alexander Viro , Jan Kara , Amir Goldstein , Li Zefan , Michal Hocko , Vladimir Davydov , Andrew Morton , Hugh Dickins , Roman Gushchin , Yang Shi , "Peter Zijlstra (Intel)" , Ingo Molnar , Mathieu Desnoyers , Andrea Arcangeli , Thomas Gleixner , linux-block@vger.kernel.org (open list:BLOCK LAYER), linux-kernel@vger.kernel.org (open list), linux-fsdevel@vger.kernel.org (open list:FILESYSTEMS (VFS and infrastructure)), cgroups@vger.kernel.org (open list:CONTROL GROUP (CGROUP)), linux-mm@kvack.org (open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)) Subject: [PATCH 3/4] mm: Charge active memcg when no mm is set Date: Mon, 20 Apr 2020 18:39:31 -0400 Message-Id: <20200420223936.6773-4-schatzberg.dan@gmail.com> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200420223936.6773-1-schatzberg.dan@gmail.com> References: <20200420223936.6773-1-schatzberg.dan@gmail.com> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: memalloc_use_memcg() worked for kernel allocations but was silently ignored for user pages. This patch establishes a precedence order for who gets charged: 1. If there is a memcg associated with the page already, that memcg is charged. This happens during swapin. 2. If an explicit mm is passed, mm->memcg is charged. This happens during page faults, which can be triggered in remote VMs (eg gup). 3. Otherwise consult the current process context. If it has configured a current->active_memcg, use that. Otherwise, current->mm->memcg. Previously, if a NULL mm was passed to mem_cgroup_try_charge (case 3) it would always charge the root cgroup. Now it looks up the current active_memcg first (falling back to charging the root cgroup if not set). Signed-off-by: Dan Schatzberg Acked-by: Johannes Weiner Acked-by: Tejun Heo Acked-by: Chris Down Reviewed-by: Shakeel Butt --- mm/memcontrol.c | 11 ++++++++--- mm/shmem.c | 4 ++-- 2 files changed, 10 insertions(+), 5 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5beea03dd58a..af68d1d7b456 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6435,7 +6435,8 @@ enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root, * @compound: charge the page as compound or small page * * Try to charge @page to the memcg that @mm belongs to, reclaiming - * pages according to @gfp_mask if necessary. + * pages according to @gfp_mask if necessary. if @mm is NULL, try to + * charge to the active memcg. * * Returns 0 on success, with *@memcgp pointing to the charged memcg. * Otherwise, an error code is returned. @@ -6479,8 +6480,12 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, } } - if (!memcg) - memcg = get_mem_cgroup_from_mm(mm); + if (!memcg) { + if (!mm) + memcg = get_mem_cgroup_from_current(); + else + memcg = get_mem_cgroup_from_mm(mm); + } ret = try_charge(memcg, gfp_mask, nr_pages); diff --git a/mm/shmem.c b/mm/shmem.c index d722eb830317..8c8ffc35a957 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1618,7 +1618,7 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index, { struct address_space *mapping = inode->i_mapping; struct shmem_inode_info *info = SHMEM_I(inode); - struct mm_struct *charge_mm = vma ? vma->vm_mm : current->mm; + struct mm_struct *charge_mm = vma ? vma->vm_mm : NULL; struct mem_cgroup *memcg; struct page *page; swp_entry_t swap; @@ -1753,7 +1753,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, } sbinfo = SHMEM_SB(inode->i_sb); - charge_mm = vma ? vma->vm_mm : current->mm; + charge_mm = vma ? vma->vm_mm : NULL; page = find_lock_entry(mapping, index); if (xa_is_value(page)) { From patchwork Mon Apr 20 22:39:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Schatzberg X-Patchwork-Id: 11500047 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B59536CA for ; Mon, 20 Apr 2020 22:41:55 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 67A6A20672 for ; Mon, 20 Apr 2020 22:41:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="MMwrbHy7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 67A6A20672 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6AE138E0009; Mon, 20 Apr 2020 18:41:54 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 610778E0003; Mon, 20 Apr 2020 18:41:54 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 48A238E0009; Mon, 20 Apr 2020 18:41:54 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0225.hostedemail.com [216.40.44.225]) by kanga.kvack.org (Postfix) with ESMTP id 2EA9C8E0003 for ; Mon, 20 Apr 2020 18:41:54 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id ED7B7824556B for ; Mon, 20 Apr 2020 22:41:53 +0000 (UTC) X-FDA: 76729707306.14.neck88_4ac091491a92c X-Spam-Summary: 2,0,0,4d3d3e96e9554378,d41d8cd98f00b204,schatzberg.dan@gmail.com,,RULES_HIT:1:2:41:69:355:379:387:541:800:960:966:973:988:989:1260:1311:1314:1345:1359:1437:1515:1605:1730:1747:1777:1792:2196:2198:2199:2200:2393:2559:2562:2901:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3872:4049:4321:4385:4605:5007:6119:6120:6121:6261:6653:6742:6743:7514:7901:7903:9413:10004:11026:11473:11658:11914:12043:12291:12296:12297:12438:12517:12519:12555:12683:12895:13161:13229:13894:14096:14394:14687:21092:21433:21444:21451:21524:21627:21666:21740:21987:21990:30012:30054:30055:30090,0,RBL:209.85.219.66:@gmail.com:.lbl8.mailshell.net-62.18.0.100 66.100.201.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: neck88_4ac091491a92c X-Filterd-Recvd-Size: 10982 Received: from mail-qv1-f66.google.com (mail-qv1-f66.google.com [209.85.219.66]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Mon, 20 Apr 2020 22:41:53 +0000 (UTC) Received: by mail-qv1-f66.google.com with SMTP id q2so2643351qvd.1 for ; Mon, 20 Apr 2020 15:41:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=3ole8TWcabCnpMGKsqdKip1VZqK6476/UWpp0kgBe70=; b=MMwrbHy7Dp4rVk0D31KjbYSihvaSGCE46LuvgK45w4aA65KXKEBm5fU9g2jxCp3iWC 4IjM9j7PdxBWHekfW/LNIE9JGRhJeNvcsSZzOXQL0DWUlIqbgIQD75ivjGUUjyIPTtEn 3vfvgpy5ZTyakNXj21uuoZ0q3YxHszsn+Mrr8jbWD5WcNdhkLX9gN0e5oX9KnyEc1oHj efT7LHIwTuNIuVMlGi+6g8nXbU0/r/YtZ78g6eRvQ4OcsBBW8d32CYiWlb+MQZoc6kFq KhDZtWyYKqUmq4i2iGxkQfZJ3N11KIr0XDyE4giauH++oehVND5feLQ8WkW/dR6UYsj3 p5Zg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; 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=3ole8TWcabCnpMGKsqdKip1VZqK6476/UWpp0kgBe70=; b=fGjWYUE1Wqz9U2elDjfEVqKZYeNruojL+AL3U84wQHHdydMd7CPvvMH4hJ08s+HPg5 FfIekjowBs3xcPXgaYNB+VvaMyFQh2Zumqx+iJSMN1l/BB6fBXfhL0dmpVThapNo9zMI LdR2hruUwTiAHQddm6oW6dD1eYhEQxTkJGlKMXaPCKTU0u9nbEA2QRCwQ2Lwk7pTHQjS QWNAofFKi8ENuUoBNgdIDyF/JNgGadJ5Rp8qoGYh4ouTPoOPwIkZSARHBCPxL58D+5gF G2Wq1HQjFj/nwFnynR+CVEz43l3iiZpNfSv6XulQ0wA2MdXWm/7hSf1r4NtmyG0RHo7P v+rw== X-Gm-Message-State: AGi0Pub0U0lwaYja4POd+CiA/hmjFLmMCqxt6M9cso5ptPBdW7ln7TwA 4I+kMgKsqm0XoGHnXpX7UoI= X-Google-Smtp-Source: APiQypIhZ4iNAXDX6ud7MgukSmGwxXNFVPbhVSSFfIGD0fZRSsa6sRjlWRUc3fEu/U8s3JGpSUVCUg== X-Received: by 2002:a0c:e305:: with SMTP id s5mr11609464qvl.234.1587422512944; Mon, 20 Apr 2020 15:41:52 -0700 (PDT) Received: from dschatzberg-fedora-PC0Y6AEN.thefacebook.com ([2620:10d:c091:480::1:b0d9]) by smtp.gmail.com with ESMTPSA id j90sm511052qte.20.2020.04.20.15.41.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Apr 2020 15:41:52 -0700 (PDT) From: Dan Schatzberg To: Cc: Dan Schatzberg , Johannes Weiner , Jens Axboe , Alexander Viro , Jan Kara , Amir Goldstein , Tejun Heo , Li Zefan , Michal Hocko , Vladimir Davydov , Andrew Morton , Hugh Dickins , Roman Gushchin , Shakeel Butt , Chris Down , Yang Shi , Ingo Molnar , "Peter Zijlstra (Intel)" , Mathieu Desnoyers , "Kirill A. Shutemov" , Andrea Arcangeli , Thomas Gleixner , linux-block@vger.kernel.org (open list:BLOCK LAYER), linux-kernel@vger.kernel.org (open list), linux-fsdevel@vger.kernel.org (open list:FILESYSTEMS (VFS and infrastructure)), cgroups@vger.kernel.org (open list:CONTROL GROUP (CGROUP)), linux-mm@kvack.org (open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)) Subject: [PATCH 4/4] loop: Charge i/o to mem and blk cg Date: Mon, 20 Apr 2020 18:39:32 -0400 Message-Id: <20200420223936.6773-5-schatzberg.dan@gmail.com> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200420223936.6773-1-schatzberg.dan@gmail.com> References: <20200420223936.6773-1-schatzberg.dan@gmail.com> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 so it can be used by the loop module. Signed-off-by: Dan Schatzberg Acked-by: Johannes Weiner --- drivers/block/loop.c | 59 +++++++++++++++++++++++++------------- drivers/block/loop.h | 3 +- include/linux/memcontrol.h | 6 ++++ kernel/cgroup/cgroup.c | 1 + 4 files changed, 48 insertions(+), 21 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 3a109975d2df..0a4838faf5e6 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -77,6 +77,7 @@ #include #include #include +#include #include "loop.h" @@ -507,8 +508,6 @@ static void lo_rw_aio_complete(struct kiocb *iocb, long ret, long ret2) { struct loop_cmd *cmd = container_of(iocb, struct loop_cmd, iocb); - if (cmd->css) - css_put(cmd->css); cmd->ret = ret; lo_rw_aio_do_completion(cmd); } @@ -569,8 +568,6 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, cmd->iocb.ki_complete = lo_rw_aio_complete; cmd->iocb.ki_flags = IOCB_DIRECT; cmd->iocb.ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0); - if (cmd->css) - kthread_associate_blkcg(cmd->css); if (rw == WRITE) ret = call_write_iter(file, &cmd->iocb, &iter); @@ -578,7 +575,6 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, ret = call_read_iter(file, &cmd->iocb, &iter); lo_rw_aio_do_completion(cmd); - kthread_associate_blkcg(NULL); if (ret != -EIOCBQUEUED) cmd->iocb.ki_complete(&cmd->iocb, ret, 0); @@ -924,7 +920,7 @@ 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; }; @@ -941,7 +937,7 @@ static void loop_queue_work(struct loop_device *lo, struct loop_cmd *cmd) spin_lock_irq(&lo->lo_lock); - if (!cmd->css) + if (!cmd->blkcg_css) goto queue_work; node = &lo->worker_tree.rb_node; @@ -949,10 +945,10 @@ static void loop_queue_work(struct loop_device *lo, struct loop_cmd *cmd) while (*node) { parent = *node; cur_worker = container_of(*node, struct loop_worker, rb_node); - if (cur_worker->css == cmd->css) { + if (cur_worker->blkcg_css == cmd->blkcg_css) { worker = cur_worker; break; - } else if ((long)cur_worker->css < (long)cmd->css) { + } else if ((long)cur_worker->blkcg_css < (long)cmd->blkcg_css) { node = &(*node)->rb_left; } else { node = &(*node)->rb_right; @@ -964,13 +960,16 @@ static void loop_queue_work(struct loop_device *lo, struct loop_cmd *cmd) worker = 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 = NULL; + cmd->memcg_css = NULL; goto queue_work; + } - worker->css = cmd->css; - css_get(worker->css); + worker->blkcg_css = 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); @@ -1221,7 +1220,7 @@ 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_lock); @@ -2030,13 +2029,18 @@ static blk_status_t loop_queue_rq(struct blk_mq_hw_ctx *hctx, } /* always use the first bio's css */ + cmd->blkcg_css = NULL; + cmd->memcg_css = NULL; #ifdef CONFIG_BLK_CGROUP - if (cmd->use_aio && rq->bio && rq->bio->bi_blkg) { - cmd->css = &bio_blkcg(rq->bio)->css; - css_get(cmd->css); - } else + if (rq->bio && rq->bio->bi_blkg) { + cmd->blkcg_css = &bio_blkcg(rq->bio)->css; +#ifdef CONFIG_MEMCG + cmd->memcg_css = + cgroup_get_e_css(cmd->blkcg_css->cgroup, + &memory_cgrp_subsys); +#endif + } #endif - cmd->css = NULL; loop_queue_work(lo, cmd); return BLK_STS_OK; @@ -2048,13 +2052,28 @@ static void loop_handle_cmd(struct loop_cmd *cmd) const bool write = op_is_write(req_op(rq)); struct loop_device *lo = rq->q->queuedata; int ret = 0; + struct mem_cgroup *old_memcg = NULL; if (write && (lo->lo_flags & LO_FLAGS_READ_ONLY)) { ret = -EIO; goto failed; } + if (cmd->blkcg_css) + kthread_associate_blkcg(cmd->blkcg_css); + if (cmd->memcg_css) + old_memcg = memalloc_use_memcg( + mem_cgroup_from_css(cmd->memcg_css)); + ret = do_req_filebacked(lo, rq); + + if (cmd->blkcg_css) + kthread_associate_blkcg(NULL); + + if (cmd->memcg_css) { + memalloc_use_memcg(old_memcg); + css_put(cmd->memcg_css); + } failed: /* complete non-aio request */ if (!cmd->use_aio || ret) { @@ -2132,7 +2151,7 @@ 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 87fd0e372227..3e65acf7a0e9 100644 --- a/drivers/block/loop.h +++ b/drivers/block/loop.h @@ -74,7 +74,8 @@ 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; }; /* Support for loadable transfer modules */ diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index d275c72c4f8e..a85cbafae6af 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -923,6 +923,12 @@ static inline struct mem_cgroup *get_mem_cgroup_from_page(struct page *page) 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 06b5ea9d899d..a3c64d961d68 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -587,6 +587,7 @@ struct cgroup_subsys_state *cgroup_get_e_css(struct cgroup *cgrp, rcu_read_unlock(); return css; } +EXPORT_SYMBOL_GPL(cgroup_get_e_css); static void cgroup_get_live(struct cgroup *cgrp) {