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[2a03:2880:ff:6::face:b00c]) by smtp.gmail.com with ESMTPSA id 25-20020a17090a031900b00274bbfc34c8sm13212320pje.16.2023.09.26.12.49.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Sep 2023 12:49:50 -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 1/2] hugetlb: memcg: account hugetlb-backed memory in memory controller Date: Tue, 26 Sep 2023 12:49:48 -0700 Message-Id: <20230926194949.2637078-2-nphamcs@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230926194949.2637078-1-nphamcs@gmail.com> References: <20230926194949.2637078-1-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 --- fs/hugetlbfs/inode.c | 2 +- include/linux/hugetlb.h | 6 ++++-- include/linux/memcontrol.h | 8 ++++++++ mm/hugetlb.c | 23 ++++++++++++++++------ mm/memcontrol.c | 40 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 70 insertions(+), 9 deletions(-) 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/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/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..e7ae63f14120 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -7050,6 +7050,46 @@ 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()) + 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 Fri Feb 13 09:30:04 2026 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 1A0E5E7D27E for ; Tue, 26 Sep 2023 19:50:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235483AbjIZTuK (ORCPT ); Tue, 26 Sep 2023 15:50:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234838AbjIZTuA (ORCPT ); Tue, 26 Sep 2023 15:50:00 -0400 Received: from mail-oi1-x230.google.com (mail-oi1-x230.google.com [IPv6:2607:f8b0:4864:20::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D88E0A3; Tue, 26 Sep 2023 12:49:52 -0700 (PDT) Received: by mail-oi1-x230.google.com with SMTP id 5614622812f47-3a86a0355dfso5544960b6e.0; Tue, 26 Sep 2023 12:49:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695757792; x=1696362592; 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=36Ec5DlRzmoQv9z0q1zeDBidbeUYibAaRRb/G9wYEfI=; b=TLHpHT/suS2GeTb8qkbTQimruiLvBzbbTpyVK5bfIhFKofkGEWFIzP5YMKapYeNH4I Wog804PXTwsyuWzMbZIrBmi3zqpTAkk8r/Re1hGXTZUT47C97sox2+DiB5dCTaynTTfz NQvrs4Yi9t+1hhxFkmj3lrVR77lHAKOf/NyQ7pDKl0UB5APMikiQbFUTyCjqOsI5wREQ 1o2Fkb0dbdUa13nfobX0JlNtg8HRx3kZNgc9CXIq39mV5LU9qKmMwH3v8wC5AlPQJtsi mXzPyaRDt7SXh2ED//BUClLChL8E3DcNWh+EskEtmigB7LEW9A/Czg49OJtbefUXPI3P QiQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695757792; x=1696362592; 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=36Ec5DlRzmoQv9z0q1zeDBidbeUYibAaRRb/G9wYEfI=; b=MWGJAASznV+WcrchYNYaTRCNngMtM6NH1dg9DnjO5n5WkiKAPKTAkonAVeVjXwJ5bh jrCaCUtz7yVAELM7pAZ2XNap0stiUq5YP+NTOKzcYAResma4BhGLOb84gjFbCwNxfOBp mwlniRW1e+QxgjepDytzpJraSRzpGckmFyBeTD0rj3q7SBY2Bd42U3q+vWV7+gss9+5r yLE2K75Z1AhaDxhoIr1Qbq9LiC0GwwPY9/ozhYwNq1GTsqGHh+NCImetDJXJ0UYjAwTc 1BHtgsBZ7/ARPhMPoe0gVaDlcUvCg5b0x/MH7Ils8k/ab2Vr0FTvDywl0F/ZWh15VXzP JPwg== X-Gm-Message-State: AOJu0YynOtYvWFKayGWZ/iL5GRbJBPBycZdXd1BrlotCukdClK8B4w46 hPdGe2WUc6Dc7tZrTIZ/+I8= X-Google-Smtp-Source: AGHT+IE9SG7tw6HLiOdoU2vIpJZrAb5VF2U/ZD9Y17VJ9SxnVN81Mx8Pnf1wdzUtPy4d45NiXjBSPQ== X-Received: by 2002:aca:1311:0:b0:3a6:f622:70f1 with SMTP id e17-20020aca1311000000b003a6f62270f1mr9105389oii.57.1695757792002; Tue, 26 Sep 2023 12:49:52 -0700 (PDT) Received: from localhost (fwdproxy-prn-016.fbsv.net. [2a03:2880:ff:10::face:b00c]) by smtp.gmail.com with ESMTPSA id i4-20020a63e444000000b0056428865aadsm10113211pgk.82.2023.09.26.12.49.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Sep 2023 12:49:51 -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 2/2] selftests: add a selftest to verify hugetlb usage in memcg Date: Tue, 26 Sep 2023 12:49:49 -0700 Message-Id: <20230926194949.2637078-3-nphamcs@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230926194949.2637078-1-nphamcs@gmail.com> References: <20230926194949.2637078-1-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 | 222 ++++++++++++++++++ 4 files changed, 227 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..9651f6af6914 --- /dev/null +++ b/tools/testing/selftests/cgroup/test_hugetlb_memcg.c @@ -0,0 +1,222 @@ +// 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"); + + 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"); + 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, 1)) { + ksft_print_msg("memory usage should increase by around 2MB.\n"); + 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, 1)) { + ksft_print_msg("memory usage should increase by around 8MB.\n"); + 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, 1)) { + ksft_print_msg("memory usage should go back down.\n"); + 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; + long old_current, expected_current, current; + + 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; + } + old_current =3D cg_read_long(test_group, "memory.current"); + + set_nr_hugepages(20); + current =3D cg_read_long(test_group, "memory.current"); + expected_current =3D old_current; + if (!values_close(expected_current, current, 10)) { + ksft_print_msg( + "memory usage should not increase after setting nr_hugepages.\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; + + /* 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