From patchwork Thu Oct 5 16:39:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Breno Leitao X-Patchwork-Id: 13410445 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 6A62EE75451 for ; Thu, 5 Oct 2023 16:46:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230443AbjJEQpm (ORCPT ); Thu, 5 Oct 2023 12:45:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58180 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231899AbjJEQpD (ORCPT ); Thu, 5 Oct 2023 12:45:03 -0400 Received: from mail-ed1-f50.google.com (mail-ed1-f50.google.com [209.85.208.50]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96C0D30F3; Thu, 5 Oct 2023 09:39:33 -0700 (PDT) Received: by mail-ed1-f50.google.com with SMTP id 4fb4d7f45d1cf-523100882f2so1987895a12.2; Thu, 05 Oct 2023 09:39:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696523972; x=1697128772; 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=CXe2b1SQetsxvQIMHBxAgfGGNR39eEXqqOWXi1pgTdY=; b=BEupe08wG2NSjwr/AnTOaNHKobTDgcxq6lOvdHG5r1Q5VNgRLIyeUwbrWuFwJsTZMd VxHwQKOAcOpZb3/Rhkyq3NbukwXxZMP+z2xK+9oXHoQaojPIxR5qVpMH9Eq9O71cJ4Hu IG0gXrTtgyaJEJeSx7HS0mCelvvGNSwEqtHeeJYTrQv7E1mvDS7wehNM3w8MHpugj9jc 7z0smVv06CvxNG6Rwx2jHZBA82oQDuzvF+22I5OB3MaPLaXhmmqy5L76bv5dpNIXD3yi Og1UR8H9bmsKXMRat4xmlcbM/iYg/FCoExkBw3yNqSjrpdP1tt0GJLcDCUDzFTjVJ+Qo LOFg== X-Gm-Message-State: AOJu0YzrZKTbu+XBURvkMuQxsTcF4QXP4OxfI63USZtRjpJqFaQIPxxt Fya7G31WlNrr+Z1VpguUZNM= X-Google-Smtp-Source: AGHT+IGYDnp74cV0Byj3XwLIm6spdtkEqH5f+zeVjCF1kcvzcQHqph+sJjv4ryOmfqgXWAqfOPwhPg== X-Received: by 2002:a17:906:2191:b0:9ae:5246:233a with SMTP id 17-20020a170906219100b009ae5246233amr4855817eju.20.1696523971836; Thu, 05 Oct 2023 09:39:31 -0700 (PDT) Received: from localhost (fwdproxy-cln-001.fbsv.net. [2a03:2880:31ff:1::face:b00c]) by smtp.gmail.com with ESMTPSA id v24-20020a1709067d9800b009b2c5363ebasm1441273ejo.26.2023.10.05.09.39.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Oct 2023 09:39:31 -0700 (PDT) From: Breno Leitao To: mike.kravetz@oracle.com, muchun.song@linux.dev, akpm@linux-foundation.org, Shuah Khan Cc: linux-mm@kvack.org, riel@surriel.com, linux-kselftest@vger.kernel.org (open list:KERNEL SELFTEST FRAMEWORK), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 1/2] selftests/mm: export get_free_hugepages() Date: Thu, 5 Oct 2023 09:39:21 -0700 Message-Id: <20231005163922.87568-2-leitao@debian.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231005163922.87568-1-leitao@debian.org> References: <20231005163922.87568-1-leitao@debian.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org get_free_hugepages() is helpful for other hugepage tests. Export it to the common file (vm_util.c) to be reused. Signed-off-by: Breno Leitao Reviewed-by: Rik van Riel --- tools/testing/selftests/mm/hugetlb-madvise.c | 19 ------------------- tools/testing/selftests/mm/vm_util.c | 19 +++++++++++++++++++ tools/testing/selftests/mm/vm_util.h | 1 + 3 files changed, 20 insertions(+), 19 deletions(-) diff --git a/tools/testing/selftests/mm/hugetlb-madvise.c b/tools/testing/selftests/mm/hugetlb-madvise.c index d55322df4b73..f32d99565c5e 100644 --- a/tools/testing/selftests/mm/hugetlb-madvise.c +++ b/tools/testing/selftests/mm/hugetlb-madvise.c @@ -36,25 +36,6 @@ unsigned long huge_page_size; unsigned long base_page_size; -unsigned long get_free_hugepages(void) -{ - unsigned long fhp = 0; - char *line = NULL; - size_t linelen = 0; - FILE *f = fopen("/proc/meminfo", "r"); - - if (!f) - return fhp; - while (getline(&line, &linelen, f) > 0) { - if (sscanf(line, "HugePages_Free: %lu", &fhp) == 1) - break; - } - - free(line); - fclose(f); - return fhp; -} - void write_fault_pages(void *addr, unsigned long nr_pages) { unsigned long i; diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c index 558c9cd8901c..3082b40492dd 100644 --- a/tools/testing/selftests/mm/vm_util.c +++ b/tools/testing/selftests/mm/vm_util.c @@ -269,3 +269,22 @@ int uffd_unregister(int uffd, void *addr, uint64_t len) return ret; } + +unsigned long get_free_hugepages(void) +{ + unsigned long fhp = 0; + char *line = NULL; + size_t linelen = 0; + FILE *f = fopen("/proc/meminfo", "r"); + + if (!f) + return fhp; + while (getline(&line, &linelen, f) > 0) { + if (sscanf(line, "HugePages_Free: %lu", &fhp) == 1) + break; + } + + free(line); + fclose(f); + return fhp; +} diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h index c7fa61f0dff8..c02990bbd56f 100644 --- a/tools/testing/selftests/mm/vm_util.h +++ b/tools/testing/selftests/mm/vm_util.h @@ -51,6 +51,7 @@ int uffd_register(int uffd, void *addr, uint64_t len, int uffd_unregister(int uffd, void *addr, uint64_t len); int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len, bool miss, bool wp, bool minor, uint64_t *ioctls); +unsigned long get_free_hugepages(void); /* * On ppc64 this will only work with radix 2M hugepage size From patchwork Thu Oct 5 16:39:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Breno Leitao X-Patchwork-Id: 13410462 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 2586EE92717 for ; Thu, 5 Oct 2023 17:08:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229682AbjJERHp (ORCPT ); Thu, 5 Oct 2023 13:07:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46538 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231430AbjJERGl (ORCPT ); Thu, 5 Oct 2023 13:06:41 -0400 Received: from mail-ej1-f44.google.com (mail-ej1-f44.google.com [209.85.218.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06BA0207B; Thu, 5 Oct 2023 09:39:36 -0700 (PDT) Received: by mail-ej1-f44.google.com with SMTP id a640c23a62f3a-99bdcade7fbso211219866b.1; Thu, 05 Oct 2023 09:39:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696523975; x=1697128775; 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=aeCkyhaoVtwv2wfDF/uieHTmRe6erji0RQ2H7V1G/pc=; b=CLw9XcKUTcoR9FNDESw3k0ELvfHePCiAn9UfPvIdrswW7yHR321+2KywQNGU6uEAob Rb4BeWafDXt2gR2ruaF+KiT0FuxHBSjO7R/TNIeKx5GaKwAKWORgd4JbmImr2bkxCef8 S2WGjkl1xXomCnysijRtoPiXupaH5D6/YkoDP2oqZWSeGdb19AFPt6T5ylzEyl0RoWKb P83cElJkGVFbhrE9mNhEVF3WF+ZItEvyesmvaLEK0aYqTBUeUVRCJ5iqAS726kJOGLBn 0WpSu7rkyWFVPFxAOhyR043PtNFf9eSH8n2I0yl2UfozBfgBhNQdGYxA4mobJh/Hg8+9 ytDQ== X-Gm-Message-State: AOJu0Yzh7735sb/9Y4uNpdwlqVtbhgW5a0mcvSdM8p6knfJLodH7B+11 A59KqAkcI8865ikCUF2inis= X-Google-Smtp-Source: AGHT+IFXpAGpAAJi5gJLJd/ylndngGVZYM9m0IP6Ma0EXz8nnBppGgbm8KmKKvk2XKyTTj6Y5Uz/ww== X-Received: by 2002:a17:906:cc2:b0:9ae:5db5:149 with SMTP id l2-20020a1709060cc200b009ae5db50149mr5073326ejh.35.1696523974869; Thu, 05 Oct 2023 09:39:34 -0700 (PDT) Received: from localhost (fwdproxy-cln-021.fbsv.net. [2a03:2880:31ff:15::face:b00c]) by smtp.gmail.com with ESMTPSA id w13-20020a170906480d00b0099b76c3041csm1447289ejq.7.2023.10.05.09.39.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Oct 2023 09:39:34 -0700 (PDT) From: Breno Leitao To: mike.kravetz@oracle.com, muchun.song@linux.dev, akpm@linux-foundation.org, Shuah Khan Cc: linux-mm@kvack.org, riel@surriel.com, linux-kernel@vger.kernel.org (open list), linux-kselftest@vger.kernel.org (open list:KERNEL SELFTEST FRAMEWORK) Subject: [PATCH v2 2/2] selftests/mm: Add a new test for madv and hugetlb Date: Thu, 5 Oct 2023 09:39:22 -0700 Message-Id: <20231005163922.87568-3-leitao@debian.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231005163922.87568-1-leitao@debian.org> References: <20231005163922.87568-1-leitao@debian.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Create a selftest that exercises the race between page faults and madvise(MADV_DONTNEED) in the same huge page. Do it by running two threads that touches the huge page and madvise(MADV_DONTNEED) at the same time. In case of a SIGBUS coming at pagefault, the test should fail, since we hit the bug. The test doesn't have a signal handler, and if it fails, it fails like the following ---------------------------------- running ./hugetlb_fault_after_madv ---------------------------------- ./run_vmtests.sh: line 186: 595563 Bus error (core dumped) "$@" [FAIL] This selftest goes together with the fix of the bug[1] itself. [1] https://lore.kernel.org/all/20231001005659.2185316-1-riel@surriel.com/#r Signed-off-by: Breno Leitao --- tools/testing/selftests/mm/Makefile | 1 + .../selftests/mm/hugetlb_fault_after_madv.c | 73 +++++++++++++++++++ tools/testing/selftests/mm/run_vmtests.sh | 4 + 3 files changed, 78 insertions(+) create mode 100644 tools/testing/selftests/mm/hugetlb_fault_after_madv.c diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile index 6a9fc5693145..e71ec9910c62 100644 --- a/tools/testing/selftests/mm/Makefile +++ b/tools/testing/selftests/mm/Makefile @@ -68,6 +68,7 @@ TEST_GEN_FILES += split_huge_page_test TEST_GEN_FILES += ksm_tests TEST_GEN_FILES += ksm_functional_tests TEST_GEN_FILES += mdwe_test +TEST_GEN_FILES += hugetlb_fault_after_madv ifneq ($(ARCH),arm64) TEST_GEN_PROGS += soft-dirty diff --git a/tools/testing/selftests/mm/hugetlb_fault_after_madv.c b/tools/testing/selftests/mm/hugetlb_fault_after_madv.c new file mode 100644 index 000000000000..73b81c632366 --- /dev/null +++ b/tools/testing/selftests/mm/hugetlb_fault_after_madv.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include + +#include "vm_util.h" +#include "../kselftest.h" + +#define MMAP_SIZE (1 << 21) +#define INLOOP_ITER 100 + +char *huge_ptr; + +/* Touch the memory while it is being madvised() */ +void *touch(void *unused) +{ + char *ptr = (char *)huge_ptr; + + for (int i = 0; i < INLOOP_ITER; i++) + ptr[0] = '.'; + + return NULL; +} + +void *madv(void *unused) +{ + usleep(rand() % 10); + + for (int i = 0; i < INLOOP_ITER; i++) + madvise(huge_ptr, MMAP_SIZE, MADV_DONTNEED); + + return NULL; +} + +int main(void) +{ + unsigned long free_hugepages; + pthread_t thread1, thread2; + /* + * On kernel 6.4, we are able to reproduce the problem with ~1000 + * interactions + */ + int max = 10000; + + srand(getpid()); + + free_hugepages = get_free_hugepages(); + if (free_hugepages != 1) { + ksft_exit_skip("This test needs one and only one page to execute. Got %lu\n", + free_hugepages); + } + + while (max--) { + huge_ptr = mmap(NULL, MMAP_SIZE, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, + -1, 0); + + if ((unsigned long)huge_ptr == -1) + ksft_exit_skip("Failed to allocated huge page\n"); + + pthread_create(&thread1, NULL, madv, NULL); + pthread_create(&thread2, NULL, touch, NULL); + + pthread_join(thread1, NULL); + pthread_join(thread2, NULL); + munmap(huge_ptr, MMAP_SIZE); + } + + return KSFT_PASS; +} diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh index 3e2bc818d566..9f53f7318a38 100755 --- a/tools/testing/selftests/mm/run_vmtests.sh +++ b/tools/testing/selftests/mm/run_vmtests.sh @@ -221,6 +221,10 @@ CATEGORY="hugetlb" run_test ./hugepage-mremap CATEGORY="hugetlb" run_test ./hugepage-vmemmap CATEGORY="hugetlb" run_test ./hugetlb-madvise +# For this test, we need one and just one huge page +echo 1 > /proc/sys/vm/nr_hugepages +CATEGORY="hugetlb" run_test ./hugetlb_fault_after_madv + if test_selected "hugetlb"; then echo "NOTE: These hugetlb tests provide minimal coverage. Use" echo " https://github.com/libhugetlbfs/libhugetlbfs.git for"