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[2a03:2880:ff:75::face:b00c]) by smtp.gmail.com with ESMTPSA id w4-20020a170902d3c400b001c737387810sm91937plb.31.2023.09.27.17.57.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 27 Sep 2023 17:57:24 -0700 (PDT) From: Nhat Pham To: akpm@linux-foundation.org Cc: riel@surriel.com, hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, muchun.song@linux.dev, tj@kernel.org, lizefan.x@bytedance.com, shuah@kernel.org, mike.kravetz@oracle.com, yosryahmed@google.com, linux-mm@kvack.org, kernel-team@meta.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: [PATCH v2 1/2] hugetlb: memcg: account hugetlb-backed memory in memory controller Date: Wed, 27 Sep 2023 17:57:22 -0700 Message-Id: <20230928005723.1709119-2-nphamcs@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230928005723.1709119-1-nphamcs@gmail.com> References: <20230928005723.1709119-1-nphamcs@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Currently, hugetlb memory usage is not acounted for in the memory controller, which could lead to memory overprotection for cgroups with hugetlb-backed memory. This has been observed in our production system. This patch rectifies this issue by charging the memcg when the hugetlb folio is allocated, and uncharging when the folio is freed (analogous to the hugetlb controller). Signed-off-by: Nhat Pham --- Documentation/admin-guide/cgroup-v2.rst | 9 ++++++ fs/hugetlbfs/inode.c | 2 +- include/linux/cgroup-defs.h | 5 +++ include/linux/hugetlb.h | 6 ++-- include/linux/memcontrol.h | 8 +++++ kernel/cgroup/cgroup.c | 15 ++++++++- mm/hugetlb.c | 23 ++++++++++---- mm/memcontrol.c | 41 +++++++++++++++++++++++++ 8 files changed, 99 insertions(+), 10 deletions(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-= guide/cgroup-v2.rst index 622a7f28db1f..e6267b8cbd1d 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -210,6 +210,15 @@ cgroup v2 currently supports the following mount optio= ns. relying on the original semantics (e.g. specifying bogusly high 'bypass' protection values at higher tree levels). =20 + memory_hugetlb_accounting + Count hugetlb memory usage towards the cgroup's overall + memory usage for the memory controller. This is a new behavior + that could regress existing setups, so it must be explicitly + opted in with this mount option. Note that hugetlb pages + allocated while this option is not selected will not be + tracked by the memory controller (even if cgroup v2 is + remounted later on). + =20 Organizing Processes and Threads -------------------------------- diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 60fce26ff937..034967319955 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -902,7 +902,7 @@ static long hugetlbfs_fallocate(struct file *file, int = mode, loff_t offset, * to keep reservation accounting consistent. */ hugetlb_set_vma_policy(&pseudo_vma, inode, index); - folio =3D alloc_hugetlb_folio(&pseudo_vma, addr, 0); + folio =3D alloc_hugetlb_folio(&pseudo_vma, addr, 0, true); hugetlb_drop_vma_policy(&pseudo_vma); if (IS_ERR(folio)) { mutex_unlock(&hugetlb_fault_mutex_table[hash]); diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index f1b3151ac30b..8641f4320c98 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -115,6 +115,11 @@ enum { * Enable recursive subtree protection */ CGRP_ROOT_MEMORY_RECURSIVE_PROT =3D (1 << 18), + + /* + * Enable hugetlb accounting for the memory controller. + */ + CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING =3D (1 << 19), }; =20 /* cftype->flags */ diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index a30686e649f7..9b73db1605a2 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -713,7 +713,8 @@ struct huge_bootmem_page { =20 int isolate_or_dissolve_huge_page(struct page *page, struct list_head *lis= t); struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, - unsigned long addr, int avoid_reserve); + unsigned long addr, int avoid_reserve, + bool restore_reserve_on_memcg_failure); struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred= _nid, nodemask_t *nmask, gfp_t gfp_mask); struct folio *alloc_hugetlb_folio_vma(struct hstate *h, struct vm_area_str= uct *vma, @@ -1016,7 +1017,8 @@ static inline int isolate_or_dissolve_huge_page(struc= t page *page, =20 static inline struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, unsigned long addr, - int avoid_reserve) + int avoid_reserve, + bool restore_reserve_on_memcg_failure) { return NULL; } diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index e0cfab58ab71..8094679c99dd 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -677,6 +677,8 @@ static inline int mem_cgroup_charge(struct folio *folio= , struct mm_struct *mm, return __mem_cgroup_charge(folio, mm, gfp); } =20 +int mem_cgroup_hugetlb_charge_folio(struct folio *folio, gfp_t gfp); + int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *= mm, gfp_t gfp, swp_entry_t entry); void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry); @@ -1251,6 +1253,12 @@ static inline int mem_cgroup_charge(struct folio *fo= lio, return 0; } =20 +static inline int mem_cgroup_hugetlb_charge_folio(struct folio *folio, + gfp_t gfp) +{ + return 0; +} + static inline int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *mm, gfp_t gfp, swp_entry_t entry) { diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 1fb7f562289d..f11488b18ceb 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -1902,6 +1902,7 @@ enum cgroup2_param { Opt_favordynmods, Opt_memory_localevents, Opt_memory_recursiveprot, + Opt_memory_hugetlb_accounting, nr__cgroup2_params }; =20 @@ -1910,6 +1911,7 @@ static const struct fs_parameter_spec cgroup2_fs_para= meters[] =3D { fsparam_flag("favordynmods", Opt_favordynmods), fsparam_flag("memory_localevents", Opt_memory_localevents), fsparam_flag("memory_recursiveprot", Opt_memory_recursiveprot), + fsparam_flag("memory_hugetlb_accounting", Opt_memory_hugetlb_accounting), {} }; =20 @@ -1936,6 +1938,9 @@ static int cgroup2_parse_param(struct fs_context *fc,= struct fs_parameter *param case Opt_memory_recursiveprot: ctx->flags |=3D CGRP_ROOT_MEMORY_RECURSIVE_PROT; return 0; + case Opt_memory_hugetlb_accounting: + ctx->flags |=3D CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING; + return 0; } return -EINVAL; } @@ -1960,6 +1965,11 @@ static void apply_cgroup_root_flags(unsigned int roo= t_flags) cgrp_dfl_root.flags |=3D CGRP_ROOT_MEMORY_RECURSIVE_PROT; else cgrp_dfl_root.flags &=3D ~CGRP_ROOT_MEMORY_RECURSIVE_PROT; + + if (root_flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING) + cgrp_dfl_root.flags |=3D CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING; + else + cgrp_dfl_root.flags &=3D ~CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING; } } =20 @@ -1973,6 +1983,8 @@ static int cgroup_show_options(struct seq_file *seq, = struct kernfs_root *kf_root seq_puts(seq, ",memory_localevents"); if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT) seq_puts(seq, ",memory_recursiveprot"); + if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING) + seq_puts(seq, ",memory_hugetlb_accounting"); return 0; } =20 @@ -7050,7 +7062,8 @@ static ssize_t features_show(struct kobject *kobj, st= ruct kobj_attribute *attr, "nsdelegate\n" "favordynmods\n" "memory_localevents\n" - "memory_recursiveprot\n"); + "memory_recursiveprot\n" + "memory_hugetlb_accounting\n"); } static struct kobj_attribute cgroup_features_attr =3D __ATTR_RO(features); =20 diff --git a/mm/hugetlb.c b/mm/hugetlb.c index de220e3ff8be..ff88ea4df11a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1902,6 +1902,7 @@ void free_huge_folio(struct folio *folio) pages_per_huge_page(h), folio); hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h), pages_per_huge_page(h), folio); + mem_cgroup_uncharge(folio); if (restore_reserve) h->resv_huge_pages++; =20 @@ -3004,7 +3005,8 @@ int isolate_or_dissolve_huge_page(struct page *page, = struct list_head *list) } =20 struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, - unsigned long addr, int avoid_reserve) + unsigned long addr, int avoid_reserve, + bool restore_reserve_on_memcg_failure) { struct hugepage_subpool *spool =3D subpool_vma(vma); struct hstate *h =3D hstate_vma(vma); @@ -3119,6 +3121,15 @@ struct folio *alloc_hugetlb_folio(struct vm_area_str= uct *vma, hugetlb_cgroup_uncharge_folio_rsvd(hstate_index(h), pages_per_huge_page(h), folio); } + + /* undo allocation if memory controller disallows it. */ + if (mem_cgroup_hugetlb_charge_folio(folio, GFP_KERNEL)) { + if (restore_reserve_on_memcg_failure) + restore_reserve_on_error(h, vma, addr, folio); + folio_put(folio); + return ERR_PTR(-ENOMEM); + } + return folio; =20 out_uncharge_cgroup: @@ -5179,7 +5190,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, st= ruct mm_struct *src, spin_unlock(src_ptl); spin_unlock(dst_ptl); /* Do not use reserve as it's private owned */ - new_folio =3D alloc_hugetlb_folio(dst_vma, addr, 1); + new_folio =3D alloc_hugetlb_folio(dst_vma, addr, 1, false); if (IS_ERR(new_folio)) { folio_put(pte_folio); ret =3D PTR_ERR(new_folio); @@ -5656,7 +5667,7 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, st= ruct vm_area_struct *vma, * be acquired again before returning to the caller, as expected. */ spin_unlock(ptl); - new_folio =3D alloc_hugetlb_folio(vma, haddr, outside_reserve); + new_folio =3D alloc_hugetlb_folio(vma, haddr, outside_reserve, true); =20 if (IS_ERR(new_folio)) { /* @@ -5930,7 +5941,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *m= m, VM_UFFD_MISSING); } =20 - folio =3D alloc_hugetlb_folio(vma, haddr, 0); + folio =3D alloc_hugetlb_folio(vma, haddr, 0, true); if (IS_ERR(folio)) { /* * Returning error will result in faulting task being @@ -6352,7 +6363,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, goto out; } =20 - folio =3D alloc_hugetlb_folio(dst_vma, dst_addr, 0); + folio =3D alloc_hugetlb_folio(dst_vma, dst_addr, 0, true); if (IS_ERR(folio)) { ret =3D -ENOMEM; goto out; @@ -6394,7 +6405,7 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, goto out; } =20 - folio =3D alloc_hugetlb_folio(dst_vma, dst_addr, 0); + folio =3D alloc_hugetlb_folio(dst_vma, dst_addr, 0, false); if (IS_ERR(folio)) { folio_put(*foliop); ret =3D -ENOMEM; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index d1a322a75172..d5dfc9b36acb 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -7050,6 +7050,47 @@ int __mem_cgroup_charge(struct folio *folio, struct = mm_struct *mm, gfp_t gfp) return ret; } =20 +static struct mem_cgroup *get_mem_cgroup_from_current(void) +{ + struct mem_cgroup *memcg; + +again: + rcu_read_lock(); + memcg =3D mem_cgroup_from_task(current); + if (!css_tryget(&memcg->css)) { + rcu_read_unlock(); + goto again; + } + rcu_read_unlock(); + return memcg; +} + +/** + * mem_cgroup_hugetlb_charge_folio - Charge a newly allocated hugetlb foli= o. + * @folio: folio to charge. + * @gfp: reclaim mode + * + * This function charges an allocated hugetlbf folio to the memcg of the + * current task. + * + * Returns 0 on success. Otherwise, an error code is returned. + */ +int mem_cgroup_hugetlb_charge_folio(struct folio *folio, gfp_t gfp) +{ + struct mem_cgroup *memcg; + int ret; + + if (mem_cgroup_disabled() || + !(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING)) + return 0; + + memcg =3D get_mem_cgroup_from_current(); + ret =3D charge_memcg(folio, memcg, gfp); + mem_cgroup_put(memcg); + + return ret; +} + /** * mem_cgroup_swapin_charge_folio - Charge a newly allocated folio for swa= pin. * @folio: folio to charge. --=20 2.34.1 From nobody Wed Dec 17 04:38:21 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55C7DE82CB7 for ; Thu, 28 Sep 2023 00:57:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229956AbjI1A5c (ORCPT ); Wed, 27 Sep 2023 20:57:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229866AbjI1A52 (ORCPT ); Wed, 27 Sep 2023 20:57:28 -0400 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B1DE0BF; Wed, 27 Sep 2023 17:57:26 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id d9443c01a7336-1bf6ea270b2so95215595ad.0; Wed, 27 Sep 2023 17:57:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695862646; x=1696467446; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=vY+Soyh4ezPzEsiTwAjxm3PLfRjJVUJ94CEs1TUSu9g=; b=E5LlVTbcfuqQp2Y8DKA4rnuwgLeHjzNovD0CqJC+xQ4cvNWbGXCzMgNHD4MHFmShXC j7sgx1PyfPRKRlchiIQBt2ZTYsHVMsJjyzEOO9crtCUCrtGy8qDy90/7MhehRjdVva77 H15vY1RUQfmNFZ4GNNujcJ35EPbn416iG3SIbAUuGo3+MU3GZ9u7n9j0LEA4NVJKv6WU jPfQmLG5Ti9MO8tAJV0JlR6oMxZWS62BRIw3VQPqoOnsCnkOvBNRITMhACCAEvU7AF8I 4RljHYJvlWnLGOdj2CrVKp0c8ZTuacKLPZrGvVyDjZ7oDZoJS1wkKQqQX9+HbRAimZNw d+AA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695862646; x=1696467446; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=vY+Soyh4ezPzEsiTwAjxm3PLfRjJVUJ94CEs1TUSu9g=; b=gbCQDtu11fiFS32h2C8WDM5psAs0v0goSpPZanLtDL4UfM6OkAjT8YQwLazOj5sX9c DywyHxTkKy3CfWJo5M6pBHVMjCFr7PPsG51oUEUTgNzAnagPOqvpF3ZrqhQauip/I+A6 WbBY1i4HUAftjxwxiNaQlfLKKwabV8AIVGDKke5FZAj+72fC6nIMwLj4poscrkjKHI9C 3iALN2+AZjmgYOqgy+Ctp5BzlCI2AavAO8a71GoPReSeovfQevy6hSiolJk6W+IsLQAS ZP7DWZccb6dyPT3E1WWGMqRSXLiTP5Ku5wMIuGxaT1gwdtLeV57G7vH7NY/AXg5+bf08 nx6Q== X-Gm-Message-State: AOJu0YwqiiRgVE67GTeXt2bTnqHKSMdDBihypeqfT3RhpFEf32BfO619 hDwTH++MKJH3yegcssY0AKs= X-Google-Smtp-Source: AGHT+IFRZZ4kr16bceFBPEJY6aoAH1hHQNJwKsnZQGk/U7syFO2CQBXtRIX2rfEbcGsKUbPNwDLQoQ== X-Received: by 2002:a17:902:a40c:b0:1c4:1b27:1cd6 with SMTP id p12-20020a170902a40c00b001c41b271cd6mr2964348plq.26.1695862646017; Wed, 27 Sep 2023 17:57:26 -0700 (PDT) Received: from localhost (fwdproxy-prn-018.fbsv.net. [2a03:2880:ff:12::face:b00c]) by smtp.gmail.com with ESMTPSA id jh1-20020a170903328100b001c60635c13esm9274548plb.115.2023.09.27.17.57.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 27 Sep 2023 17:57:25 -0700 (PDT) From: Nhat Pham To: akpm@linux-foundation.org Cc: riel@surriel.com, hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, muchun.song@linux.dev, tj@kernel.org, lizefan.x@bytedance.com, shuah@kernel.org, mike.kravetz@oracle.com, yosryahmed@google.com, linux-mm@kvack.org, kernel-team@meta.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: [PATCH v2 2/2] selftests: add a selftest to verify hugetlb usage in memcg Date: Wed, 27 Sep 2023 17:57:23 -0700 Message-Id: <20230928005723.1709119-3-nphamcs@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230928005723.1709119-1-nphamcs@gmail.com> References: <20230928005723.1709119-1-nphamcs@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This patch add a new kselftest to demonstrate and verify the new hugetlb memcg accounting behavior. Signed-off-by: Nhat Pham --- MAINTAINERS | 2 + tools/testing/selftests/cgroup/.gitignore | 1 + tools/testing/selftests/cgroup/Makefile | 2 + .../selftests/cgroup/test_hugetlb_memcg.c | 234 ++++++++++++++++++ 4 files changed, 239 insertions(+) create mode 100644 tools/testing/selftests/cgroup/test_hugetlb_memcg.c diff --git a/MAINTAINERS b/MAINTAINERS index bf0f54c24f81..ce9f40bcc2ba 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5269,6 +5269,7 @@ S: Maintained F: mm/memcontrol.c F: mm/swap_cgroup.c F: tools/testing/selftests/cgroup/memcg_protection.m +F: tools/testing/selftests/cgroup/test_hugetlb_memcg.c F: tools/testing/selftests/cgroup/test_kmem.c F: tools/testing/selftests/cgroup/test_memcontrol.c =20 @@ -9652,6 +9653,7 @@ F: include/linux/hugetlb.h F: mm/hugetlb.c F: mm/hugetlb_vmemmap.c F: mm/hugetlb_vmemmap.h +F: tools/testing/selftests/cgroup/test_hugetlb_memcg.c =20 HVA ST MEDIA DRIVER M: Jean-Christophe Trotin diff --git a/tools/testing/selftests/cgroup/.gitignore b/tools/testing/self= tests/cgroup/.gitignore index af8c3f30b9c1..2732e0b29271 100644 --- a/tools/testing/selftests/cgroup/.gitignore +++ b/tools/testing/selftests/cgroup/.gitignore @@ -7,4 +7,5 @@ test_kill test_cpu test_cpuset test_zswap +test_hugetlb_memcg wait_inotify diff --git a/tools/testing/selftests/cgroup/Makefile b/tools/testing/selfte= sts/cgroup/Makefile index c27f05f6ce9b..00b441928909 100644 --- a/tools/testing/selftests/cgroup/Makefile +++ b/tools/testing/selftests/cgroup/Makefile @@ -14,6 +14,7 @@ TEST_GEN_PROGS +=3D test_kill TEST_GEN_PROGS +=3D test_cpu TEST_GEN_PROGS +=3D test_cpuset TEST_GEN_PROGS +=3D test_zswap +TEST_GEN_PROGS +=3D test_hugetlb_memcg =20 LOCAL_HDRS +=3D $(selfdir)/clone3/clone3_selftests.h $(selfdir)/pidfd/pidf= d.h =20 @@ -27,3 +28,4 @@ $(OUTPUT)/test_kill: cgroup_util.c $(OUTPUT)/test_cpu: cgroup_util.c $(OUTPUT)/test_cpuset: cgroup_util.c $(OUTPUT)/test_zswap: cgroup_util.c +$(OUTPUT)/test_hugetlb_memcg: cgroup_util.c diff --git a/tools/testing/selftests/cgroup/test_hugetlb_memcg.c b/tools/te= sting/selftests/cgroup/test_hugetlb_memcg.c new file mode 100644 index 000000000000..f0fefeb4cc24 --- /dev/null +++ b/tools/testing/selftests/cgroup/test_hugetlb_memcg.c @@ -0,0 +1,234 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include "../kselftest.h" +#include "cgroup_util.h" + +#define ADDR ((void *)(0x0UL)) +#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB) +/* mapping 8 MBs =3D=3D 4 hugepages */ +#define LENGTH (8UL*1024*1024) +#define PROTECTION (PROT_READ | PROT_WRITE) + +/* borrowed from mm/hmm-tests.c */ +static long get_hugepage_size(void) +{ + int fd; + char buf[2048]; + int len; + char *p, *q, *path =3D "/proc/meminfo", *tag =3D "Hugepagesize:"; + long val; + + fd =3D open(path, O_RDONLY); + if (fd < 0) { + /* Error opening the file */ + return -1; + } + + len =3D read(fd, buf, sizeof(buf)); + close(fd); + if (len < 0) { + /* Error in reading the file */ + return -1; + } + if (len =3D=3D sizeof(buf)) { + /* Error file is too large */ + return -1; + } + buf[len] =3D '\0'; + + /* Search for a tag if provided */ + if (tag) { + p =3D strstr(buf, tag); + if (!p) + return -1; /* looks like the line we want isn't there */ + p +=3D strlen(tag); + } else + p =3D buf; + + val =3D strtol(p, &q, 0); + if (*q !=3D ' ') { + /* Error parsing the file */ + return -1; + } + + return val; +} + +static int set_file(const char *path, long value) +{ + FILE *file; + int ret; + + file =3D fopen(path, "w"); + if (!file) + return -1; + ret =3D fprintf(file, "%ld\n", value); + fclose(file); + return ret; +} + +static int set_nr_hugepages(long value) +{ + return set_file("/proc/sys/vm/nr_hugepages", value); +} + +static unsigned int check_first(char *addr) +{ + return *(unsigned int *)addr; +} + +static void write_data(char *addr) +{ + unsigned long i; + + for (i =3D 0; i < LENGTH; i++) + *(addr + i) =3D (char)i; +} + +static int hugetlb_test_program(const char *cgroup, void *arg) +{ + char *test_group =3D (char *)arg; + void *addr; + long old_current, expected_current, current; + int ret =3D EXIT_FAILURE; + + old_current =3D cg_read_long(test_group, "memory.current"); + set_nr_hugepages(20); + current =3D cg_read_long(test_group, "memory.current"); + if (current - old_current >=3D MB(2)) { + ksft_print_msg( + "setting nr_hugepages should not increase hugepage usage.\n"); + ksft_print_msg("before: %ld, after: %ld\n", old_current, current); + return EXIT_FAILURE; + } + + addr =3D mmap(ADDR, LENGTH, PROTECTION, FLAGS, 0, 0); + if (addr =3D=3D MAP_FAILED) { + ksft_print_msg("fail to mmap.\n"); + return EXIT_FAILURE; + } + current =3D cg_read_long(test_group, "memory.current"); + if (current - old_current >=3D MB(2)) { + ksft_print_msg("mmap should not increase hugepage usage.\n"); + ksft_print_msg("before: %ld, after: %ld\n", old_current, current); + goto out_failed_munmap; + } + old_current =3D current; + + /* read the first page */ + check_first(addr); + expected_current =3D old_current + MB(2); + current =3D cg_read_long(test_group, "memory.current"); + if (!values_close(expected_current, current, 5)) { + ksft_print_msg("memory usage should increase by around 2MB.\n"); + ksft_print_msg( + "expected memory: %ld, actual memory: %ld\n", + expected_current, current); + goto out_failed_munmap; + } + + /* write to the whole range */ + write_data(addr); + current =3D cg_read_long(test_group, "memory.current"); + expected_current =3D old_current + MB(8); + if (!values_close(expected_current, current, 5)) { + ksft_print_msg("memory usage should increase by around 8MB.\n"); + ksft_print_msg( + "expected memory: %ld, actual memory: %ld\n", + expected_current, current); + goto out_failed_munmap; + } + + /* unmap the whole range */ + munmap(addr, LENGTH); + current =3D cg_read_long(test_group, "memory.current"); + expected_current =3D old_current; + if (!values_close(expected_current, current, 5)) { + ksft_print_msg("memory usage should go back down.\n"); + ksft_print_msg( + "expected memory: %ld, actual memory: %ld\n", + expected_current, current); + return ret; + } + + ret =3D EXIT_SUCCESS; + return ret; + +out_failed_munmap: + munmap(addr, LENGTH); + return ret; +} + +static int test_hugetlb_memcg(char *root) +{ + int ret =3D KSFT_FAIL; + char *test_group; + + test_group =3D cg_name(root, "hugetlb_memcg_test"); + if (!test_group || cg_create(test_group)) { + ksft_print_msg("fail to create cgroup.\n"); + goto out; + } + + if (cg_write(test_group, "memory.max", "100M")) { + ksft_print_msg("fail to set cgroup memory limit.\n"); + goto out; + } + + /* disable swap */ + if (cg_write(test_group, "memory.swap.max", "0")) { + ksft_print_msg("fail to disable swap.\n"); + goto out; + } + + if (!cg_run(test_group, hugetlb_test_program, (void *)test_group)) + ret =3D KSFT_PASS; +out: + cg_destroy(test_group); + free(test_group); + return ret; +} + +int main(int argc, char **argv) +{ + char root[PATH_MAX]; + int ret =3D EXIT_SUCCESS, has_memory_hugetlb_acc; + + has_memory_hugetlb_acc =3D proc_mount_contains("memory_hugetlb_accounting= "); + if (has_memory_hugetlb_acc < 0) + ksft_exit_skip("Failed to query cgroup mount option\n"); + else if (!has_memory_hugetlb_acc) + ksft_exit_skip("memory hugetlb accounting is disabled\n"); + + /* Unit is kB! */ + if (get_hugepage_size() !=3D 2048) { + ksft_print_msg("test_hugetlb_memcg requires 2MB hugepages\n"); + ksft_test_result_skip("test_hugetlb_memcg\n"); + return ret; + } + + if (cg_find_unified_root(root, sizeof(root))) + ksft_exit_skip("cgroup v2 isn't mounted\n"); + + switch (test_hugetlb_memcg(root)) { + case KSFT_PASS: + ksft_test_result_pass("test_hugetlb_memcg\n"); + break; + case KSFT_SKIP: + ksft_test_result_skip("test_hugetlb_memcg\n"); + break; + default: + ret =3D EXIT_FAILURE; + ksft_test_result_fail("test_hugetlb_memcg\n"); + break; + } + + return ret; +} --=20 2.34.1