From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E3A94C433DB for ; Wed, 24 Mar 2021 23:08:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6C06761A10 for ; Wed, 24 Mar 2021 23:08:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C06761A10 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D1FEA6B0338; Wed, 24 Mar 2021 19:08:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CCFAF6B0339; Wed, 24 Mar 2021 19:08:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B49296B033A; Wed, 24 Mar 2021 19:08:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0109.hostedemail.com [216.40.44.109]) by kanga.kvack.org (Postfix) with ESMTP id 962EC6B0338 for ; Wed, 24 Mar 2021 19:08:15 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 5BEB9BA07 for ; Wed, 24 Mar 2021 23:08:15 +0000 (UTC) X-FDA: 77956308150.27.47FA676 Received: from mail-pf1-f179.google.com (mail-pf1-f179.google.com [209.85.210.179]) by imf07.hostedemail.com (Postfix) with ESMTP id 62478A0000FA for ; Wed, 24 Mar 2021 23:08:12 +0000 (UTC) Received: by mail-pf1-f179.google.com with SMTP id q5so19776pfh.10 for ; Wed, 24 Mar 2021 16:08:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=LhJhGY7Q5ru7P/G4ZIy6MS5lulzSiDOAC2gYoWDjKkI=; b=JtjxGuZTnRN8SsbC+reXyjYrtvOWHSfxDZe8oC3b6FiLfH1J+fzhbhoz9WXg7+OgzL 4PdyVffKyhw8+sNjNHobOu8dM3wQd4tGm85U9o+RXK4hHG7qgHhlt/q2SrU1feQ3ay9w BGEFv/uErKAQzrrs0E5pQKGkAhdulz5Pddza4BoRD3P87/H54BZQNCfgOpTi4oo9Q7mo nGrPM3jrO/TBW9K+Zo005e7NFpUMZ7U4DAeEI4kuw6McajVSnHlzOywGaEf13blHOLVL SUu4fksu1rBtHcNa4RTXTIiH8ICdzlrhn3LecQbekz3VPysagDZSezRwchGWqoewkGFk yARg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :mime-version:content-transfer-encoding; bh=LhJhGY7Q5ru7P/G4ZIy6MS5lulzSiDOAC2gYoWDjKkI=; b=ZZbxmX9TJyEelWrTjGW1Vx3sN9GudNUZusBKqqEhlH8iRVGDlRdQPFvcFeIebnv0Ml Ue0FdZJwaEyJ1sbpKsgM+J3kLfjKqFFe5i499aARyfnuXHf8jrnFf7ElV9GechMryCaH WS70VoalMHUz1mlRDSjL/W2FfyEBQkXkbPxZKRHv3Htf74np3VG5/qC0X8zn6UDzucFI hScCr+86tUfndYQj970JlegmDbrkzIyZx7AOeu1LRGZzN0hI6BkH46zCh2tDL4v4NIrs Fs9zfBNorFhjeJjye6V4X/b5we0uBtf6EfQ/CzPQJUNLzqrqwpyPSsnIz2VhBpyJLsBS h+ag== X-Gm-Message-State: AOAM532riLVjBQ2mYyDTVflJZotkzJwHmQkJCryFZv37T///KRAFM4kn bHEzh2jSfw0AVGBe/qAhPlc= X-Google-Smtp-Source: ABdhPJxPQIzgu9G1dflapKvbnLoi6DZuHnQq3AKrHxYW5e038JpboEU+vJE+x2DREaN0i6Ta36FXHg== X-Received: by 2002:a63:531e:: with SMTP id h30mr4995363pgb.158.1616627291717; Wed, 24 Mar 2021 16:08:11 -0700 (PDT) Received: from bbox-1.mtv.corp.google.com ([2620:15c:211:201:7dfa:1e53:536:7976]) by smtp.gmail.com with ESMTPSA id u1sm3385122pgg.11.2021.03.24.16.08.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Mar 2021 16:08:10 -0700 (PDT) From: Minchan Kim To: Andrew Morton Cc: linux-mm , LKML , gregkh@linuxfoundation.org, surenb@google.com, joaodias@google.com, jhubbard@nvidia.com, willy@infradead.org, digetx@gmail.com, Minchan Kim , Colin Ian King Subject: [PATCH v8] mm: cma: support sysfs Date: Wed, 24 Mar 2021 16:07:59 -0700 Message-Id: <20210324230759.2213957-1-minchan@kernel.org> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog MIME-Version: 1.0 X-Stat-Signature: bwrdcacw7m6xshctwrgrg9tio815d8y7 X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 62478A0000FA Received-SPF: none (gmail.com>: No applicable sender policy available) receiver=imf07; identity=mailfrom; envelope-from=""; helo=mail-pf1-f179.google.com; client-ip=209.85.210.179 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616627292-10500 Content-Transfer-Encoding: quoted-printable 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: Since CMA is getting used more widely, it's more important to keep monitoring CMA statistics for system health since it's directly related to user experience. This patch introduces sysfs statistics for CMA, in order to provide some basic monitoring of the CMA allocator. * the number of CMA page successful allocations * the number of CMA page allocation failures These two values allow the user to calcuate the allocation failure rate for each CMA area. e.g.) /sys/kernel/mm/cma/WIFI/alloc_pages_[success|fail] /sys/kernel/mm/cma/SENSOR/alloc_pages_[success|fail] /sys/kernel/mm/cma/BLUETOOTH/alloc_pages_[success|fail] The cma_stat was intentionally allocated by dynamic allocation to harmonize with kobject lifetime management. https://lore.kernel.org/linux-mm/YCOAmXqt6dZkCQYs@kroah.com/ Tested-by: Dmitry Osipenko Reviewed-by: Dmitry Osipenko Reviewed-by: Greg Kroah-Hartman Reviewed-by: John Hubbard Link: https://lore.kernel.org/linux-mm/20210316100433.17665-1-colin.king@= canonical.com/ Addresses-Coverity: ("Dereference after null check") Signed-off-by: Colin Ian King Signed-off-by: Minchan Kim --- Andrew, you could apply this patch after revering these patches: mm: cma: fix potential null dereference on pointer cma mm: cma: support sysfs >From v7 - https://lore.kernel.org/linux-mm/20210324205503.2132082-1-minch= an@kernel.org/ >From v6 - https://lore.kernel.org/linux-mm/20210324010547.4134370-1-minch= an@kernel.org/ >From v5 - https://lore.kernel.org/linux-mm/20210323195050.2577017-1-minch= an@kernel.org/ >From v4 - https://lore.kernel.org/linux-mm/20210309062333.3216138-1-minch= an@kernel.org/ * fix corruption - digetx@ * refactoring - digetx@, jhubbard@, willy@ >From v4 - https://lore.kernel.org/linux-mm/20210309062333.3216138-1-minch= an@kernel.org/ * fix corruption - digetx@ >From v3 - https://lore.kernel.org/linux-mm/20210303205053.2906924-1-minch= an@kernel.org/ * fix ZERO_OR_NULL_PTR - kernel test robot * remove prefix cma - david@ * resolve conflict with vmstat cma in mmotm - akpm@ * rename stat name with success|fail >From v2 - https://lore.kernel.org/linux-mm/20210208180142.2765456-1-minch= an@kernel.org/ * sysfs doc and description modification - jhubbard >From v1 - https://lore.kernel.org/linux-mm/20210203155001.4121868-1-minch= an@kernel.org/ * fix sysfs build and refactoring - willy * rename and drop some attributes - jhubbard Documentation/ABI/testing/sysfs-kernel-mm-cma | 25 ++++ mm/Kconfig | 7 ++ mm/Makefile | 1 + mm/cma.c | 8 +- mm/cma.h | 23 ++++ mm/cma_sysfs.c | 112 ++++++++++++++++++ 6 files changed, 174 insertions(+), 2 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-kernel-mm-cma create mode 100644 mm/cma_sysfs.c diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-cma b/Documentatio= n/ABI/testing/sysfs-kernel-mm-cma new file mode 100644 index 000000000000..02b2bb60c296 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-mm-cma @@ -0,0 +1,25 @@ +What: /sys/kernel/mm/cma/ +Date: Feb 2021 +Contact: Minchan Kim +Description: + /sys/kernel/mm/cma/ contains a subdirectory for each CMA + heap name (also sometimes called CMA areas). + + Each CMA heap subdirectory (that is, each + /sys/kernel/mm/cma/ directory) contains the + following items: + + alloc_pages_success + alloc_pages_fail + +What: /sys/kernel/mm/cma//alloc_pages_success +Date: Feb 2021 +Contact: Minchan Kim +Description: + the number of pages CMA API succeeded to allocate + +What: /sys/kernel/mm/cma//alloc_pages_fail +Date: Feb 2021 +Contact: Minchan Kim +Description: + the number of pages CMA API failed to allocate diff --git a/mm/Kconfig b/mm/Kconfig index 23a0e3c98ff0..3823a2314256 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -524,6 +524,13 @@ config CMA_DEBUGFS help Turns on the DebugFS interface for CMA. =20 +config CMA_SYSFS + bool "CMA information through sysfs interface" + depends on CMA && SYSFS + help + This option exposes some sysfs attributes to get information + from CMA. + config CMA_AREAS int "Maximum count of the CMA areas" depends on CMA diff --git a/mm/Makefile b/mm/Makefile index 9e284dba50ef..788c5ce5c0ef 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -112,6 +112,7 @@ obj-$(CONFIG_CMA) +=3D cma.o obj-$(CONFIG_MEMORY_BALLOON) +=3D balloon_compaction.o obj-$(CONFIG_PAGE_EXTENSION) +=3D page_ext.o obj-$(CONFIG_CMA_DEBUGFS) +=3D cma_debug.o +obj-$(CONFIG_CMA_SYSFS) +=3D cma_sysfs.o obj-$(CONFIG_USERFAULTFD) +=3D userfaultfd.o obj-$(CONFIG_IDLE_PAGE_TRACKING) +=3D page_idle.o obj-$(CONFIG_DEBUG_PAGE_REF) +=3D debug_page_ref.o diff --git a/mm/cma.c b/mm/cma.c index 0361e289c31a..08c45157911a 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -507,10 +507,14 @@ struct page *cma_alloc(struct cma *cma, size_t coun= t, unsigned int align, =20 pr_debug("%s(): returned %p\n", __func__, page); out: - if (page) + if (page) { count_vm_event(CMA_ALLOC_SUCCESS); - else + cma_sysfs_account_success_pages(cma, count); + } else { count_vm_event(CMA_ALLOC_FAIL); + if (cma) + cma_sysfs_account_fail_pages(cma, count); + } =20 return page; } diff --git a/mm/cma.h b/mm/cma.h index 42ae082cb067..68ffad4e430d 100644 --- a/mm/cma.h +++ b/mm/cma.h @@ -3,6 +3,12 @@ #define __MM_CMA_H__ =20 #include +#include + +struct cma_kobject { + struct kobject kobj; + struct cma *cma; +}; =20 struct cma { unsigned long base_pfn; @@ -16,6 +22,14 @@ struct cma { struct debugfs_u32_array dfs_bitmap; #endif char name[CMA_MAX_NAME]; +#ifdef CONFIG_CMA_SYSFS + /* the number of CMA page successful allocations */ + atomic64_t nr_pages_succeeded; + /* the number of CMA page allocation failures */ + atomic64_t nr_pages_failed; + /* kobject requires dynamic object */ + struct cma_kobject *cma_kobj; +#endif }; =20 extern struct cma cma_areas[MAX_CMA_AREAS]; @@ -26,4 +40,13 @@ static inline unsigned long cma_bitmap_maxno(struct cm= a *cma) return cma->count >> cma->order_per_bit; } =20 +#ifdef CONFIG_CMA_SYSFS +void cma_sysfs_account_success_pages(struct cma *cma, unsigned long nr_p= ages); +void cma_sysfs_account_fail_pages(struct cma *cma, unsigned long nr_page= s); +#else +static inline void cma_sysfs_account_success_pages(struct cma *cma, + unsigned long nr_pages) {}; +static inline void cma_sysfs_account_fail_pages(struct cma *cma, + unsigned long nr_pages) {}; +#endif #endif diff --git a/mm/cma_sysfs.c b/mm/cma_sysfs.c new file mode 100644 index 000000000000..eb2f39caff59 --- /dev/null +++ b/mm/cma_sysfs.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * CMA SysFS Interface + * + * Copyright (c) 2021 Minchan Kim + */ + +#include +#include +#include + +#include "cma.h" + +#define CMA_ATTR_RO(_name) \ + static struct kobj_attribute _name##_attr =3D __ATTR_RO(_name) + +void cma_sysfs_account_success_pages(struct cma *cma, unsigned long nr_p= ages) +{ + atomic64_add(nr_pages, &cma->nr_pages_succeeded); +} + +void cma_sysfs_account_fail_pages(struct cma *cma, unsigned long nr_page= s) +{ + atomic64_add(nr_pages, &cma->nr_pages_failed); +} + +static inline struct cma *cma_from_kobj(struct kobject *kobj) +{ + return container_of(kobj, struct cma_kobject, kobj)->cma; +} + +static ssize_t alloc_pages_success_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct cma *cma =3D cma_from_kobj(kobj); + + return sysfs_emit(buf, "%llu\n", + atomic64_read(&cma->nr_pages_succeeded)); +} +CMA_ATTR_RO(alloc_pages_success); + +static ssize_t alloc_pages_fail_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct cma *cma =3D cma_from_kobj(kobj); + + return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_failed)); +} +CMA_ATTR_RO(alloc_pages_fail); + +static void cma_kobj_release(struct kobject *kobj) +{ + struct cma *cma =3D cma_from_kobj(kobj); + struct cma_kobject *cma_kobj =3D cma->cma_kobj; + + kfree(cma_kobj); + cma->cma_kobj =3D NULL; +} + +static struct attribute *cma_attrs[] =3D { + &alloc_pages_success_attr.attr, + &alloc_pages_fail_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(cma); + +static struct kobj_type cma_ktype =3D { + .release =3D cma_kobj_release, + .sysfs_ops =3D &kobj_sysfs_ops, + .default_groups =3D cma_groups, +}; + +static int __init cma_sysfs_init(void) +{ + struct kobject *cma_kobj_root; + struct cma_kobject *cma_kobj; + struct cma *cma; + int i, err; + + cma_kobj_root =3D kobject_create_and_add("cma", mm_kobj); + if (!cma_kobj_root) + return -ENOMEM; + + for (i =3D 0; i < cma_area_count; i++) { + cma_kobj =3D kzalloc(sizeof(*cma_kobj), GFP_KERNEL); + if (!cma_kobj) { + err =3D -ENOMEM; + goto out; + } + + cma =3D &cma_areas[i]; + cma->cma_kobj =3D cma_kobj; + cma_kobj->cma =3D cma; + err =3D kobject_init_and_add(&cma_kobj->kobj, &cma_ktype, + cma_kobj_root, "%s", cma->name); + if (err) { + kobject_put(&cma_kobj->kobj); + goto out; + } + } + + return 0; +out: + while (--i >=3D 0) { + cma =3D &cma_areas[i]; + kobject_put(&cma->cma_kobj->kobj); + } + kobject_put(cma_kobj_root); + + return err; +} +subsys_initcall(cma_sysfs_init); --=20 2.31.0.291.g576ba9dcdaf-goog