From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vk0-f71.google.com (mail-vk0-f71.google.com [209.85.213.71]) by kanga.kvack.org (Postfix) with ESMTP id 58CF46B0253 for ; Wed, 4 Oct 2017 13:15:46 -0400 (EDT) Received: by mail-vk0-f71.google.com with SMTP id q75so6185488vkf.4 for ; Wed, 04 Oct 2017 10:15:46 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id n1si4140347qte.108.2017.10.04.10.15.45 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 04 Oct 2017 10:15:45 -0700 (PDT) From: Andrea Arcangeli Subject: [PATCH 1/1] userfaultfd: selftest: exercise -EEXIST only in background transfer Date: Wed, 4 Oct 2017 19:15:41 +0200 Message-Id: <20171004171541.1495-2-aarcange@redhat.com> In-Reply-To: <20171004171541.1495-1-aarcange@redhat.com> References: <20171004171541.1495-1-aarcange@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , linux-mm@kvack.org Cc: Pavel Emelyanov , Mike Rapoport , "Dr. David Alan Gilbert" , Mike Kravetz The fork child will quit after the last UFFDIO_COPY is run, so a repeated UFFDIO_COPY may not return -EEXIST. This change restricts the -EEXIST stress to the background transfer where the memory can't go away from under it. Also updated uffdio_zeropage, so the interface is consistent. Signed-off-by: Andrea Arcangeli --- tools/testing/selftests/vm/userfaultfd.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index a2c53a3d223d..de2f9ec8a87f 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -397,7 +397,7 @@ static void retry_copy_page(int ufd, struct uffdio_copy *uffdio_copy, } } -static int copy_page(int ufd, unsigned long offset) +static int __copy_page(int ufd, unsigned long offset, bool retry) { struct uffdio_copy uffdio_copy; @@ -418,7 +418,7 @@ static int copy_page(int ufd, unsigned long offset) fprintf(stderr, "UFFDIO_COPY unexpected copy %Ld\n", uffdio_copy.copy), exit(1); } else { - if (test_uffdio_copy_eexist) { + if (test_uffdio_copy_eexist && retry) { test_uffdio_copy_eexist = false; retry_copy_page(ufd, &uffdio_copy, offset); } @@ -427,6 +427,16 @@ static int copy_page(int ufd, unsigned long offset) return 0; } +static int copy_page_retry(int ufd, unsigned long offset) +{ + return __copy_page(ufd, offset, true); +} + +static int copy_page(int ufd, unsigned long offset) +{ + return __copy_page(ufd, offset, false); +} + static void *uffd_poll_thread(void *arg) { unsigned long cpu = (unsigned long) arg; @@ -544,7 +554,7 @@ static void *background_thread(void *arg) for (page_nr = cpu * nr_pages_per_cpu; page_nr < (cpu+1) * nr_pages_per_cpu; page_nr++) - copy_page(uffd, page_nr * page_size); + copy_page_retry(uffd, page_nr * page_size); return NULL; } @@ -779,7 +789,7 @@ static void retry_uffdio_zeropage(int ufd, } } -static int uffdio_zeropage(int ufd, unsigned long offset) +static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) { struct uffdio_zeropage uffdio_zeropage; int ret; @@ -814,7 +824,7 @@ static int uffdio_zeropage(int ufd, unsigned long offset) fprintf(stderr, "UFFDIO_ZEROPAGE unexpected %Ld\n", uffdio_zeropage.zeropage), exit(1); } else { - if (test_uffdio_zeropage_eexist) { + if (test_uffdio_zeropage_eexist && retry) { test_uffdio_zeropage_eexist = false; retry_uffdio_zeropage(ufd, &uffdio_zeropage, offset); @@ -830,6 +840,11 @@ static int uffdio_zeropage(int ufd, unsigned long offset) return 0; } +static int uffdio_zeropage(int ufd, unsigned long offset) +{ + return __uffdio_zeropage(ufd, offset, false); +} + /* exercise UFFDIO_ZEROPAGE */ static int userfaultfd_zeropage_test(void) { -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org