From patchwork Sun Sep 30 07:42:57 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Xu X-Patchwork-Id: 10621187 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DCEBC15A7 for ; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D22E3295D2 for ; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C6A27295EA; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6ED9B295D5 for ; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728003AbeI3OPG (ORCPT ); Sun, 30 Sep 2018 10:15:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40886 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727651AbeI3OPG (ORCPT ); Sun, 30 Sep 2018 10:15:06 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F2B734E90D; Sun, 30 Sep 2018 07:43:11 +0000 (UTC) Received: from xz-x1.nay.redhat.com (dhcp-14-128.nay.redhat.com [10.66.14.128]) by smtp.corp.redhat.com (Postfix) with ESMTP id AAF8A60164; Sun, 30 Sep 2018 07:43:07 +0000 (UTC) From: Peter Xu To: linux-kernel@vger.kernel.org Cc: Shuah Khan , Mike Kravetz , Mike Rapoport , Jerome Glisse , peterx@redhat.com, linux-mm@kvack.org, Zi Yan , "Kirill A . Shutemov" , linux-kselftest@vger.kernel.org, Shaohua Li , Andrea Arcangeli , "Dr . David Alan Gilbert" , Andrew Morton Subject: [PATCH v2 1/3] userfaultfd: selftest: cleanup help messages Date: Sun, 30 Sep 2018 15:42:57 +0800 Message-Id: <20180930074259.18229-2-peterx@redhat.com> In-Reply-To: <20180930074259.18229-1-peterx@redhat.com> References: <20180930074259.18229-1-peterx@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Sun, 30 Sep 2018 07:43:12 +0000 (UTC) Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Firstly, the help in the comment region is obsolete, now we support three parameters. Since at it, change it and move it into the help message of the program. Also, the help messages dumped here and there is obsolete too. Use a single usage() helper. Acked-by: Mike Rapoport Signed-off-by: Peter Xu --- tools/testing/selftests/vm/userfaultfd.c | 46 ++++++++++++++---------- 1 file changed, 28 insertions(+), 18 deletions(-) diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 7b8171e3128a..5ff3a4f9173e 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -34,18 +34,6 @@ * per-CPU threads 1 by triggering userfaults inside * pthread_mutex_lock will also verify the atomicity of the memory * transfer (UFFDIO_COPY). - * - * The program takes two parameters: the amounts of physical memory in - * megabytes (MiB) of the area and the number of bounces to execute. - * - * # 100MiB 99999 bounces - * ./userfaultfd 100 99999 - * - * # 1GiB 99 bounces - * ./userfaultfd 1000 99 - * - * # 10MiB-~6GiB 999 bounces, continue forever unless an error triggers - * while ./userfaultfd $[RANDOM % 6000 + 10] 999; do true; done */ #define _GNU_SOURCE @@ -115,6 +103,30 @@ pthread_attr_t attr; ~(unsigned long)(sizeof(unsigned long long) \ - 1))) +const char *examples = + "# Run anonymous memory test on 100MiB region with 99999 bounces:\n" + "./userfaultfd anon 100 99999\n\n" + "# Run share memory test on 1GiB region with 99 bounces:\n" + "./userfaultfd shmem 1000 99\n\n" + "# Run hugetlb memory test on 256MiB region with 50 bounces (using /dev/hugepages/hugefile):\n" + "./userfaultfd hugetlb 256 50 /dev/hugepages/hugefile\n\n" + "# Run the same hugetlb test but using shmem:\n" + "./userfaultfd hugetlb_shared 256 50 /dev/hugepages/hugefile\n\n" + "# 10MiB-~6GiB 999 bounces anonymous test, " + "continue forever unless an error triggers\n" + "while ./userfaultfd anon $[RANDOM % 6000 + 10] 999; do true; done\n\n"; + +static void usage(void) +{ + fprintf(stderr, "\nUsage: ./userfaultfd " + "[hugetlbfs_file]\n\n"); + fprintf(stderr, "Supported : anon, hugetlb, " + "hugetlb_shared, shmem\n\n"); + fprintf(stderr, "Examples:\n\n"); + fprintf(stderr, examples); + exit(1); +} + static int anon_release_pages(char *rel_area) { int ret = 0; @@ -1272,8 +1284,7 @@ static void sigalrm(int sig) int main(int argc, char **argv) { if (argc < 4) - fprintf(stderr, "Usage: [hugetlbfs_file]\n"), - exit(1); + usage(); if (signal(SIGALRM, sigalrm) == SIG_ERR) fprintf(stderr, "failed to arm SIGALRM"), exit(1); @@ -1286,20 +1297,19 @@ int main(int argc, char **argv) nr_cpus; if (!nr_pages_per_cpu) { fprintf(stderr, "invalid MiB\n"); - fprintf(stderr, "Usage: \n"), exit(1); + usage(); } bounces = atoi(argv[3]); if (bounces <= 0) { fprintf(stderr, "invalid bounces\n"); - fprintf(stderr, "Usage: \n"), exit(1); + usage(); } nr_pages = nr_pages_per_cpu * nr_cpus; if (test_type == TEST_HUGETLB) { if (argc < 5) - fprintf(stderr, "Usage: hugetlb \n"), - exit(1); + usage(); huge_fd = open(argv[4], O_CREAT | O_RDWR, 0755); if (huge_fd < 0) { fprintf(stderr, "Open of %s failed", argv[3]); From patchwork Sun Sep 30 07:42:58 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Xu X-Patchwork-Id: 10621185 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C49D814BD for ; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B8BFF295D2 for ; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AD830295E3; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4E376295D2 for ; Sun, 30 Sep 2018 07:43:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728081AbeI3OPL (ORCPT ); Sun, 30 Sep 2018 10:15:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36532 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727651AbeI3OPL (ORCPT ); Sun, 30 Sep 2018 10:15:11 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C26BA81F0B; Sun, 30 Sep 2018 07:43:16 +0000 (UTC) Received: from xz-x1.nay.redhat.com (dhcp-14-128.nay.redhat.com [10.66.14.128]) by smtp.corp.redhat.com (Postfix) with ESMTP id 786306016F; Sun, 30 Sep 2018 07:43:12 +0000 (UTC) From: Peter Xu To: linux-kernel@vger.kernel.org Cc: Shuah Khan , Mike Kravetz , Mike Rapoport , Jerome Glisse , peterx@redhat.com, linux-mm@kvack.org, Zi Yan , "Kirill A . Shutemov" , linux-kselftest@vger.kernel.org, Shaohua Li , Andrea Arcangeli , "Dr . David Alan Gilbert" , Andrew Morton Subject: [PATCH v2 2/3] userfaultfd: selftest: generalize read and poll Date: Sun, 30 Sep 2018 15:42:58 +0800 Message-Id: <20180930074259.18229-3-peterx@redhat.com> In-Reply-To: <20180930074259.18229-1-peterx@redhat.com> References: <20180930074259.18229-1-peterx@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Sun, 30 Sep 2018 07:43:16 +0000 (UTC) Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP We do very similar things in read and poll modes, but we're copying the codes around. Share the codes properly on reading the message and handling the page fault to make the code cleaner. Meanwhile this solves previous mismatch of behaviors between the two modes on that the old code: - did not check EAGAIN case in read() mode - ignored BOUNCE_VERIFY check in read() mode Signed-off-by: Peter Xu Acked-by: Mike Rapoport --- tools/testing/selftests/vm/userfaultfd.c | 77 +++++++++++++----------- 1 file changed, 43 insertions(+), 34 deletions(-) diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 5ff3a4f9173e..7a8c6937cc67 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -451,6 +451,43 @@ static int copy_page(int ufd, unsigned long offset) return __copy_page(ufd, offset, false); } +static int uffd_read_msg(int ufd, struct uffd_msg *msg) +{ + int ret = read(uffd, msg, sizeof(*msg)); + + if (ret != sizeof(*msg)) { + if (ret < 0) { + if (errno == EAGAIN) + return 1; + else + perror("blocking read error"), exit(1); + } else { + fprintf(stderr, "short read\n"), exit(1); + } + } + + return 0; +} + +/* Return 1 if page fault handled by us; otherwise 0 */ +static int uffd_handle_page_fault(struct uffd_msg *msg) +{ + unsigned long offset; + + if (msg->event != UFFD_EVENT_PAGEFAULT) + fprintf(stderr, "unexpected msg event %u\n", + msg->event), exit(1); + + if (bounces & BOUNCE_VERIFY && + msg->arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE) + fprintf(stderr, "unexpected write fault\n"), exit(1); + + offset = (char *)(unsigned long)msg->arg.pagefault.address - area_dst; + offset &= ~(page_size-1); + + return copy_page(uffd, offset); +} + static void *uffd_poll_thread(void *arg) { unsigned long cpu = (unsigned long) arg; @@ -458,7 +495,6 @@ static void *uffd_poll_thread(void *arg) struct uffd_msg msg; struct uffdio_register uffd_reg; int ret; - unsigned long offset; char tmp_chr; unsigned long userfaults = 0; @@ -482,25 +518,15 @@ static void *uffd_poll_thread(void *arg) if (!(pollfd[0].revents & POLLIN)) fprintf(stderr, "pollfd[0].revents %d\n", pollfd[0].revents), exit(1); - ret = read(uffd, &msg, sizeof(msg)); - if (ret < 0) { - if (errno == EAGAIN) - continue; - perror("nonblocking read error"), exit(1); - } + if (uffd_read_msg(uffd, &msg)) + continue; switch (msg.event) { default: fprintf(stderr, "unexpected msg event %u\n", msg.event), exit(1); break; case UFFD_EVENT_PAGEFAULT: - if (msg.arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE) - fprintf(stderr, "unexpected write fault\n"), exit(1); - offset = (char *)(unsigned long)msg.arg.pagefault.address - - area_dst; - offset &= ~(page_size-1); - if (copy_page(uffd, offset)) - userfaults++; + userfaults += uffd_handle_page_fault(&msg); break; case UFFD_EVENT_FORK: close(uffd); @@ -528,8 +554,6 @@ static void *uffd_read_thread(void *arg) { unsigned long *this_cpu_userfaults; struct uffd_msg msg; - unsigned long offset; - int ret; this_cpu_userfaults = (unsigned long *) arg; *this_cpu_userfaults = 0; @@ -538,24 +562,9 @@ static void *uffd_read_thread(void *arg) /* from here cancellation is ok */ for (;;) { - ret = read(uffd, &msg, sizeof(msg)); - if (ret != sizeof(msg)) { - if (ret < 0) - perror("blocking read error"), exit(1); - else - fprintf(stderr, "short read\n"), exit(1); - } - if (msg.event != UFFD_EVENT_PAGEFAULT) - fprintf(stderr, "unexpected msg event %u\n", - msg.event), exit(1); - if (bounces & BOUNCE_VERIFY && - msg.arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE) - fprintf(stderr, "unexpected write fault\n"), exit(1); - offset = (char *)(unsigned long)msg.arg.pagefault.address - - area_dst; - offset &= ~(page_size-1); - if (copy_page(uffd, offset)) - (*this_cpu_userfaults)++; + if (uffd_read_msg(uffd, &msg)) + continue; + (*this_cpu_userfaults) += uffd_handle_page_fault(&msg); } return (void *)NULL; } From patchwork Sun Sep 30 07:42:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Xu X-Patchwork-Id: 10621183 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E4BB814BD for ; Sun, 30 Sep 2018 07:43:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D9F12295D2 for ; Sun, 30 Sep 2018 07:43:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CDB5C295DD; Sun, 30 Sep 2018 07:43:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 888FA295D2 for ; Sun, 30 Sep 2018 07:43:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726133AbeI3OPP (ORCPT ); Sun, 30 Sep 2018 10:15:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49152 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727651AbeI3OPP (ORCPT ); Sun, 30 Sep 2018 10:15:15 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8D75FA70A; Sun, 30 Sep 2018 07:43:21 +0000 (UTC) Received: from xz-x1.nay.redhat.com (dhcp-14-128.nay.redhat.com [10.66.14.128]) by smtp.corp.redhat.com (Postfix) with ESMTP id 470DD60164; Sun, 30 Sep 2018 07:43:17 +0000 (UTC) From: Peter Xu To: linux-kernel@vger.kernel.org Cc: Shuah Khan , Mike Kravetz , Mike Rapoport , Jerome Glisse , peterx@redhat.com, linux-mm@kvack.org, Zi Yan , "Kirill A . Shutemov" , linux-kselftest@vger.kernel.org, Shaohua Li , Andrea Arcangeli , "Dr . David Alan Gilbert" , Andrew Morton Subject: [PATCH v2 3/3] userfaultfd: selftest: recycle lock threads first Date: Sun, 30 Sep 2018 15:42:59 +0800 Message-Id: <20180930074259.18229-4-peterx@redhat.com> In-Reply-To: <20180930074259.18229-1-peterx@redhat.com> References: <20180930074259.18229-1-peterx@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Sun, 30 Sep 2018 07:43:21 +0000 (UTC) Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Now we recycle the uffd servicing threads earlier than the lock threads. It might happen that when the lock thread is still blocked at a pthread mutex lock while the servicing thread has already quitted for the cpu so the lock thread will be blocked forever and hang the test program. To fix the possible race, recycle the lock threads first. This never happens with current missing-only tests, but when I start to run the write-protection tests (the feature is not yet posted upstream) it happens every time of the run possibly because in that new test we'll need to service two page faults for each lock operation. Acked-by: Mike Rapoport Signed-off-by: Peter Xu --- tools/testing/selftests/vm/userfaultfd.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 7a8c6937cc67..5d1db824f73a 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -626,6 +626,12 @@ static int stress(unsigned long *userfaults) if (uffd_test_ops->release_pages(area_src)) return 1; + + finished = 1; + for (cpu = 0; cpu < nr_cpus; cpu++) + if (pthread_join(locking_threads[cpu], NULL)) + return 1; + for (cpu = 0; cpu < nr_cpus; cpu++) { char c; if (bounces & BOUNCE_POLL) { @@ -643,11 +649,6 @@ static int stress(unsigned long *userfaults) } } - finished = 1; - for (cpu = 0; cpu < nr_cpus; cpu++) - if (pthread_join(locking_threads[cpu], NULL)) - return 1; - return 0; }