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 X-Spam-Level: X-Spam-Status: No, score=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74C23C433ED for ; Mon, 17 May 2021 23:57:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54BC86113C for ; Mon, 17 May 2021 23:57:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344719AbhEQX7I (ORCPT ); Mon, 17 May 2021 19:59:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238461AbhEQX7F (ORCPT ); Mon, 17 May 2021 19:59:05 -0400 Received: from mail-il1-x136.google.com (mail-il1-x136.google.com [IPv6:2607:f8b0:4864:20::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EB0BC061756 for ; Mon, 17 May 2021 16:57:48 -0700 (PDT) Received: by mail-il1-x136.google.com with SMTP id g11so3564557ilq.3 for ; Mon, 17 May 2021 16:57:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=vOazABg9O+2XA5M9CuZX/N0TNZ6RBivTs+Mo+Q+WgWs=; b=KmRIRoilurSyzHxqWjtm94m0ajkMPMP3RarWiSMgcfsV4vufHyJFf64a4L8+tpY4OM wpqYdIxQ1vny3/no9PGGwuMFpDztqBc3weA9Xwt7Zg4tI/zMi66/ZZijXKZNLSVqkmrS LYXEQvEDFjbni661NfXnOxfk2zmaPrQ3+vDPLfGHDncfGUXfHT02GIF7ricWHFYhQZNM 6nTVCMCSRBVq0DhwKVP//mkTY72d7m6bUtkt5ZDW6dBvL34Xlu7AtzUGUjRi2UayPrV1 JeXj7KTRY1XIatq7pq++OFnkbo9S5+UgGNZsyX3cp/axcZj2YzeIbDy0ntm8p52VPFY3 ukUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=vOazABg9O+2XA5M9CuZX/N0TNZ6RBivTs+Mo+Q+WgWs=; b=gDLR5olulQvupXMV2qmJDyH/tRV/5SFzd3YmWsexVfddbMMpX6MABQGrxySRmftSS8 llQOJ8/IB28MGrK26KhPI/TFuqGqmJDK2Pmz1fCun4SaRXj1oYEBiu8y8lgybpqJpB6T HshdgKmYlJvwBO2Uu/z2h+T8c96mthJGk3Nk9OnMS0j6JyV6co+J0EZEug0BWI9/GeU0 hgcoHFgA4nPK3X6Oh9urCYXGvo999eBg5E4V1CzUOD0NJjBMpohtAtkrexyFX25S34M2 iKlVMyDEyDqxfxPIZp+tC4P9YU+3ikV7HRzHeQWE7WQK7mxXxJZAr6P7hz2AOpGXyNJ+ Fy7g== X-Gm-Message-State: AOAM5326q54RDtR94eAHFglFaKiQBlHleYgZyqamNFZA0P5bp6/jjr8+ dO7QLuQ/eA13TLw9BbWkNhvAc5g39F2ccENUMD4Fiw== X-Google-Smtp-Source: ABdhPJxcMcCrR9keQbmzXUQr9lFt5sFgF2BdB25XfuMyFNfSbZddtliDhmfMSVEEhhKqyUGgR6F2DwK2DZR3zWhzgQw= X-Received: by 2002:a05:6e02:1a49:: with SMTP id u9mr1959195ilv.306.1621295867710; Mon, 17 May 2021 16:57:47 -0700 (PDT) MIME-Version: 1.0 References: <20210512214502.2047008-1-axelrasmussen@google.com> <20210512214502.2047008-6-axelrasmussen@google.com> In-Reply-To: <20210512214502.2047008-6-axelrasmussen@google.com> From: Ben Gardon Date: Mon, 17 May 2021 16:57:37 -0700 Message-ID: Subject: Re: [PATCH 5/5] KVM: selftests: add shared hugetlbfs backing source type To: Axel Rasmussen Cc: Aaron Lewis , Alexander Graf , Andrew Jones , Andrew Morton , Emanuele Giuseppe Esposito , Eric Auger , Jacob Xu , Makarand Sonare , Oliver Upton , Paolo Bonzini , Peter Xu , Shuah Khan , Yanan Wang , kvm , LKML , linux-kselftest@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 12, 2021 at 2:45 PM Axel Rasmussen wrote: > > This lets us run the demand paging test on top of a shared > hugetlbfs-backed area. The "shared" is key, as this allows us to > exercise userfaultfd minor faults on hugetlbfs. > > Signed-off-by: Axel Rasmussen > --- > tools/testing/selftests/kvm/demand_paging_test.c | 6 ++++-- > tools/testing/selftests/kvm/include/test_util.h | 10 ++++++++++ > tools/testing/selftests/kvm/lib/kvm_util.c | 9 +++++++-- > tools/testing/selftests/kvm/lib/test_util.c | 6 ++++++ > 4 files changed, 27 insertions(+), 4 deletions(-) > > diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c > index ff29aaea3120..32942c9e0376 100644 > --- a/tools/testing/selftests/kvm/demand_paging_test.c > +++ b/tools/testing/selftests/kvm/demand_paging_test.c > @@ -502,8 +502,10 @@ int main(int argc, char *argv[]) > } > } > > - TEST_ASSERT(p.uffd_mode != UFFDIO_REGISTER_MODE_MINOR || p.src_type == VM_MEM_SRC_SHMEM, > - "userfaultfd MINOR mode requires shared memory; pick a different -t"); > + if (p.uffd_mode == UFFDIO_REGISTER_MODE_MINOR && > + !backing_src_is_shared(p.src_type)) { > + TEST_FAIL("userfaultfd MINOR mode requires shared memory; pick a different -t"); > + } > > for_each_guest_mode(run_test, &p); > > diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h > index 7377f00469ef..852d6d2cc285 100644 > --- a/tools/testing/selftests/kvm/include/test_util.h > +++ b/tools/testing/selftests/kvm/include/test_util.h > @@ -85,9 +85,19 @@ enum vm_mem_backing_src_type { > VM_MEM_SRC_ANONYMOUS_HUGETLB_2GB, > VM_MEM_SRC_ANONYMOUS_HUGETLB_16GB, > VM_MEM_SRC_SHMEM, > + VM_MEM_SRC_SHARED_HUGETLB, > NUM_SRC_TYPES, > }; > > +/* > + * Whether or not the given source type is shared memory (as opposed to > + * anonymous). > + */ > +static inline bool backing_src_is_shared(enum vm_mem_backing_src_type t) > +{ > + return t == VM_MEM_SRC_SHMEM || t == VM_MEM_SRC_SHARED_HUGETLB; > +} Would it make sense to check (vm_mem_backing_src_alias(t)->flag & MAP_SHARED) == MAP_SHARED instead? > + > struct vm_mem_backing_src_alias { > const char *name; > uint32_t flag; > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c > index 838d58633f7e..fed02153c919 100644 > --- a/tools/testing/selftests/kvm/lib/kvm_util.c > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c > @@ -756,8 +756,13 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, > region->mmap_size += alignment; > > region->fd = -1; > - if (src_type == VM_MEM_SRC_SHMEM) { > - region->fd = memfd_create("kvm_selftest", MFD_CLOEXEC); > + if (backing_src_is_shared(src_type)) { > + int memfd_flags = MFD_CLOEXEC; > + > + if (src_type == VM_MEM_SRC_SHARED_HUGETLB) > + memfd_flags |= MFD_HUGETLB; > + > + region->fd = memfd_create("kvm_selftest", memfd_flags); > TEST_ASSERT(region->fd != -1, > "memfd_create failed, errno: %i", errno); > > diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c > index c7a265da5090..65fb8b43782c 100644 > --- a/tools/testing/selftests/kvm/lib/test_util.c > +++ b/tools/testing/selftests/kvm/lib/test_util.c > @@ -240,6 +240,11 @@ const struct vm_mem_backing_src_alias *vm_mem_backing_src_alias(uint32_t i) > .name = "shmem", > .flag = MAP_SHARED, > }, > + [VM_MEM_SRC_SHARED_HUGETLB] = { > + .name = "shared_hugetlb", > + /* No MAP_HUGETLB, we use MFD_HUGETLB instead. */ Is it worth calling out the difference between the two flags here? > + .flag = MAP_SHARED, > + }, > }; > _Static_assert(ARRAY_SIZE(aliases) == NUM_SRC_TYPES, > "Missing new backing src types?"); > @@ -262,6 +267,7 @@ size_t get_backing_src_pagesz(uint32_t i) > case VM_MEM_SRC_ANONYMOUS_THP: > return get_trans_hugepagesz(); > case VM_MEM_SRC_ANONYMOUS_HUGETLB: > + case VM_MEM_SRC_SHARED_HUGETLB: > return get_def_hugetlb_pagesz(); > default: > return MAP_HUGE_PAGE_SIZE(flag); > -- > 2.31.1.607.g51e8a6a459-goog >