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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5DCFDC4332F for ; Fri, 25 Mar 2022 01:33:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353016AbiCYBeg (ORCPT ); Thu, 24 Mar 2022 21:34:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357620AbiCYBdf (ORCPT ); Thu, 24 Mar 2022 21:33:35 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3350DA94D3 for ; Thu, 24 Mar 2022 18:32:02 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id D59C4B82725 for ; Fri, 25 Mar 2022 01:32:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6CE71C340EC; Fri, 25 Mar 2022 01:31:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1648171919; bh=Ek4/pxEfArjqCikUQiRbYSibCWxSGSvI7JTBmMSWtBk=; h=Date:To:From:Subject:From; b=LnYOxy2SA6FRCDLtq2JzFALR1KdLSW00s6Q8UnQoRaLm39HGzwsbMfl1jIW1EcV4E /qPp9WIkLPKARLlWMeRDsF0zt9mNWLEy49k2nvWijEPIgnjkqnBVQZpddw3+0jqGaH wAzOEHjzWx0r0E8gvDkNeoB1/Ka4jevp9UoVWMyw= Date: Thu, 24 Mar 2022 18:31:58 -0700 To: mm-commits@vger.kernel.org, zhengqi.arch@bytedance.com, willy@infradead.org, song.bao.hua@hisilicon.com, osalvador@suse.de, mike.kravetz@oracle.com, mhocko@suse.com, fam.zheng@bytedance.com, duanxiongchun@bytedance.com, david@redhat.com, corbet@lwn.net, chenhuang5@huawei.com, bodeddub@amazon.com, songmuchun@bytedance.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged] selftests-vm-add-a-hugetlb-test-case.patch removed from -mm tree Message-Id: <20220325013159.6CE71C340EC@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: selftests: vm: add a hugetlb test case has been removed from the -mm tree. Its filename was selftests-vm-add-a-hugetlb-test-case.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Muchun Song Subject: selftests: vm: add a hugetlb test case Since the head vmemmap page frame associated with each HugeTLB page is reused, we should hide the PG_head flag of tail struct page from the user. Add a tese case to check whether it is work properly. The test steps are as follows. 1) alloc 2MB hugeTLB 2) get each page frame 3) apply those APIs in each page frame 4) Those APIs work completely the same as before. Reading the flags of a page by /proc/kpageflags is done in stable_page_flags(), which has invoked PageHead(), PageTail(), PageCompound() and compound_head(). If those APIs work properly, the head page must have 15 and 17 bits set. And tail pages must have 16 and 17 bits set but 15 bit unset. Those flags are checked in check_page_flags(). Link: https://lkml.kernel.org/r/20211101031651.75851-5-songmuchun@bytedance.com Signed-off-by: Muchun Song Reviewed-by: Barry Song Cc: Bodeddula Balasubramaniam Cc: Chen Huang Cc: David Hildenbrand Cc: Fam Zheng Cc: Jonathan Corbet Cc: Matthew Wilcox Cc: Michal Hocko Cc: Mike Kravetz Cc: Oscar Salvador Cc: Qi Zheng Cc: Xiongchun Duan Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/.gitignore | 1 tools/testing/selftests/vm/Makefile | 1 tools/testing/selftests/vm/hugepage-vmemmap.c | 144 ++++++++++++++++ tools/testing/selftests/vm/run_vmtests.sh | 11 + 4 files changed, 157 insertions(+) --- a/tools/testing/selftests/vm/.gitignore~selftests-vm-add-a-hugetlb-test-case +++ a/tools/testing/selftests/vm/.gitignore @@ -2,6 +2,7 @@ hugepage-mmap hugepage-mremap hugepage-shm +hugepage-vmemmap khugepaged map_hugetlb map_populate --- /dev/null +++ a/tools/testing/selftests/vm/hugepage-vmemmap.c @@ -0,0 +1,144 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A test case of using hugepage memory in a user application using the + * mmap system call with MAP_HUGETLB flag. Before running this program + * make sure the administrator has allocated enough default sized huge + * pages to cover the 2 MB allocation. + */ +#include +#include +#include +#include +#include + +#define MAP_LENGTH (2UL * 1024 * 1024) + +#ifndef MAP_HUGETLB +#define MAP_HUGETLB 0x40000 /* arch specific */ +#endif + +#define PAGE_SIZE 4096 + +#define PAGE_COMPOUND_HEAD (1UL << 15) +#define PAGE_COMPOUND_TAIL (1UL << 16) +#define PAGE_HUGE (1UL << 17) + +#define HEAD_PAGE_FLAGS (PAGE_COMPOUND_HEAD | PAGE_HUGE) +#define TAIL_PAGE_FLAGS (PAGE_COMPOUND_TAIL | PAGE_HUGE) + +#define PM_PFRAME_BITS 55 +#define PM_PFRAME_MASK ~((1UL << PM_PFRAME_BITS) - 1) + +/* + * For ia64 architecture, Linux kernel reserves Region number 4 for hugepages. + * That means the addresses starting with 0x800000... will need to be + * specified. Specifying a fixed address is not required on ppc64, i386 + * or x86_64. + */ +#ifdef __ia64__ +#define MAP_ADDR (void *)(0x8000000000000000UL) +#define MAP_FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED) +#else +#define MAP_ADDR NULL +#define MAP_FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB) +#endif + +static void write_bytes(char *addr, size_t length) +{ + unsigned long i; + + for (i = 0; i < length; i++) + *(addr + i) = (char)i; +} + +static unsigned long virt_to_pfn(void *addr) +{ + int fd; + unsigned long pagemap; + + fd = open("/proc/self/pagemap", O_RDONLY); + if (fd < 0) + return -1UL; + + lseek(fd, (unsigned long)addr / PAGE_SIZE * sizeof(pagemap), SEEK_SET); + read(fd, &pagemap, sizeof(pagemap)); + close(fd); + + return pagemap & ~PM_PFRAME_MASK; +} + +static int check_page_flags(unsigned long pfn) +{ + int fd, i; + unsigned long pageflags; + + fd = open("/proc/kpageflags", O_RDONLY); + if (fd < 0) + return -1; + + lseek(fd, pfn * sizeof(pageflags), SEEK_SET); + + read(fd, &pageflags, sizeof(pageflags)); + if ((pageflags & HEAD_PAGE_FLAGS) != HEAD_PAGE_FLAGS) { + close(fd); + printf("Head page flags (%lx) is invalid\n", pageflags); + return -1; + } + + /* + * pages other than the first page must be tail and shouldn't be head; + * this also verifies kernel has correctly set the fake page_head to tail + * while hugetlb_free_vmemmap is enabled. + */ + for (i = 1; i < MAP_LENGTH / PAGE_SIZE; i++) { + read(fd, &pageflags, sizeof(pageflags)); + if ((pageflags & TAIL_PAGE_FLAGS) != TAIL_PAGE_FLAGS || + (pageflags & HEAD_PAGE_FLAGS) == HEAD_PAGE_FLAGS) { + close(fd); + printf("Tail page flags (%lx) is invalid\n", pageflags); + return -1; + } + } + + close(fd); + + return 0; +} + +int main(int argc, char **argv) +{ + void *addr; + unsigned long pfn; + + addr = mmap(MAP_ADDR, MAP_LENGTH, PROT_READ | PROT_WRITE, MAP_FLAGS, -1, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + /* Trigger allocation of HugeTLB page. */ + write_bytes(addr, MAP_LENGTH); + + pfn = virt_to_pfn(addr); + if (pfn == -1UL) { + munmap(addr, MAP_LENGTH); + perror("virt_to_pfn"); + exit(1); + } + + printf("Returned address is %p whose pfn is %lx\n", addr, pfn); + + if (check_page_flags(pfn) < 0) { + munmap(addr, MAP_LENGTH); + perror("check_page_flags"); + exit(1); + } + + /* munmap() length of MAP_HUGETLB memory must be hugepage aligned */ + if (munmap(addr, MAP_LENGTH)) { + perror("munmap"); + exit(1); + } + + return 0; +} --- a/tools/testing/selftests/vm/Makefile~selftests-vm-add-a-hugetlb-test-case +++ a/tools/testing/selftests/vm/Makefile @@ -33,6 +33,7 @@ TEST_GEN_FILES += hmm-tests TEST_GEN_FILES += hugepage-mmap TEST_GEN_FILES += hugepage-mremap TEST_GEN_FILES += hugepage-shm +TEST_GEN_FILES += hugepage-vmemmap TEST_GEN_FILES += khugepaged TEST_GEN_FILES += madv_populate TEST_GEN_FILES += map_fixed_noreplace --- a/tools/testing/selftests/vm/run_vmtests.sh~selftests-vm-add-a-hugetlb-test-case +++ a/tools/testing/selftests/vm/run_vmtests.sh @@ -120,6 +120,17 @@ else fi rm -f $mnt/huge_mremap +echo "------------------------" +echo "running hugepage-vmemmap" +echo "------------------------" +./hugepage-vmemmap +if [ $? -ne 0 ]; then + echo "[FAIL]" + exitcode=1 +else + echo "[PASS]" +fi + echo "NOTE: The above hugetlb tests provide minimal coverage. Use" echo " https://github.com/libhugetlbfs/libhugetlbfs.git for" echo " hugetlb regression testing." _ Patches currently in -mm which might be from songmuchun@bytedance.com are