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=-14.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham 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 3AE25C33C9B for ; Tue, 7 Jan 2020 21:18:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EFEC42077B for ; Tue, 7 Jan 2020 21:18:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="jvwFbmRe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728992AbgAGVS2 (ORCPT ); Tue, 7 Jan 2020 16:18:28 -0500 Received: from mail-vk1-f193.google.com ([209.85.221.193]:35312 "EHLO mail-vk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729068AbgAGVSV (ORCPT ); Tue, 7 Jan 2020 16:18:21 -0500 Received: by mail-vk1-f193.google.com with SMTP id o187so388503vka.2 for ; Tue, 07 Jan 2020 13:18:20 -0800 (PST) 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=fWHlfsIIqdm4CbdrtbAbeq2yRN1pjIyOoBGlDv3Smng=; b=jvwFbmReRt9SroYc8ybUNmLn1tiPYK6p8ILrC7V9oODm6acKcSC0C5Z8srJwQzhEky mK9jaymqbeaX8fnhrt09ztan8PSQq6YqcFBdPcbK4IN+2+f9zMXdtieX3/PL5TN4ul+E 3PNCrM9CpCXg8SplB7jDlsZzz42uDf4zq2EsO9Z7NsGjZEkZn0FawYvjONzy/AVNfqoF HEeV4oUbrc4kC1PgQ0mkJS53oPISOckpJv5VRNmxgSFZUsXnwulO9dFrFATaYD8Vawi1 6tIjCJa4UGyZFPHI9PjWHvd6UTWXCXwNmKYZ71udv3gZzFJ2eEOpRdzT3vETXRFDwKcn 3NKQ== 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=fWHlfsIIqdm4CbdrtbAbeq2yRN1pjIyOoBGlDv3Smng=; b=r5pMMA5UaN2qO3GRA+6Xqv3XNFrQ+vNgyYTvtH98/PXH7EA6vyQpSlU/6cDfQ8GYZV sbH4xzUYbV5YPbDrj7FWjLYallkR2bFI6T16opuo/YvfTcmfMxoGP1eGBKWOVG2CbhdE /54Cm0W3yMJxeSFQTU44L/TqDs1l7RMUHTp3SXd/C4z1jhEyKsoW51fAwRKmSqd84zG8 xQ61uoZdV50/5p9Vmb6rF8Z5c+wfjjkLRAejNM1JhdfwueZHgBilZTt6jyNhyGxa3MHd qIyeVI537/Qt1mQBQBd7SN9y+Ue/uu2Oz2ePHxFAXUJ4+35mk/pGTKGR3HxnDLC3EYF7 Nw+g== X-Gm-Message-State: APjAAAWXZ4Mei+8R9dx7JcOS0r+KH+U0nL1zQkRGM2u7vqGhA8LKHbMe OSx2BxR4BRHITeaStQwARV5nICCEJQczCpYVwUksDw== X-Google-Smtp-Source: APXvYqxumwkbw/b3bQhS1QzSVsUSdF39aqCErT/H6DqIdEW/GJF4vkawveLg6w1NU6pRre6WHkV6HbdXHk9+c9kEkTU= X-Received: by 2002:a1f:1fd1:: with SMTP id f200mr957892vkf.21.1578431899872; Tue, 07 Jan 2020 13:18:19 -0800 (PST) MIME-Version: 1.0 References: <20191216213901.106941-1-bgardon@google.com> <20191216213901.106941-5-bgardon@google.com> <20200107150245.cblsqirr5mu4fqoo@kamzik.brq.redhat.com> In-Reply-To: <20200107150245.cblsqirr5mu4fqoo@kamzik.brq.redhat.com> From: Ben Gardon Date: Tue, 7 Jan 2020 13:18:08 -0800 Message-ID: Subject: Re: [PATCH v3 4/8] KVM: selftests: Add memory size parameter to the demand paging test To: Andrew Jones Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, Paolo Bonzini , Cannon Matthews , Peter Xu Content-Type: text/plain; charset="UTF-8" Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On Tue, Jan 7, 2020 at 7:02 AM Andrew Jones wrote: > > On Mon, Dec 16, 2019 at 01:38:57PM -0800, Ben Gardon wrote: > > Add an argument to allow the demand paging test to work on larger and > > smaller guest sizes. > > > > Signed-off-by: Ben Gardon > > --- > > .../selftests/kvm/demand_paging_test.c | 56 ++++++++++++------- > > 1 file changed, 35 insertions(+), 21 deletions(-) > > > > diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c > > index 11de5b58995fb..4aa90a3fce99c 100644 > > --- a/tools/testing/selftests/kvm/demand_paging_test.c > > +++ b/tools/testing/selftests/kvm/demand_paging_test.c > > @@ -32,6 +32,8 @@ > > /* Default guest test virtual memory offset */ > > #define DEFAULT_GUEST_TEST_MEM 0xc0000000 > > > > +#define DEFAULT_GUEST_TEST_MEM_SIZE (1 << 30) /* 1G */ > > + > > /* > > * Guest/Host shared variables. Ensure addr_gva2hva() and/or > > * sync_global_to/from_guest() are used when accessing from > > @@ -264,11 +266,10 @@ static int setup_demand_paging(struct kvm_vm *vm, > > return 0; > > } > > > > -#define GUEST_MEM_SHIFT 30 /* 1G */ > > #define PAGE_SHIFT_4K 12 > > > > static void run_test(enum vm_guest_mode mode, bool use_uffd, > > - useconds_t uffd_delay) > > + useconds_t uffd_delay, uint64_t guest_memory_bytes) > > { > > pthread_t vcpu_thread; > > pthread_t uffd_handler_thread; > > @@ -276,33 +277,40 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd, > > int r; > > > > /* > > - * We reserve page table for 2 times of extra dirty mem which > > - * will definitely cover the original (1G+) test range. Here > > - * we do the calculation with 4K page size which is the > > - * smallest so the page number will be enough for all archs > > - * (e.g., 64K page size guest will need even less memory for > > - * page tables). > > + * We reserve page table for twice the ammount of memory we intend > > + * to use in the test region for demand paging. Here we do the > > + * calculation with 4K page size which is the smallest so the page > > + * number will be enough for all archs. (e.g., 64K page size guest > > + * will need even less memory for page tables). > > */ > > vm = create_vm(mode, VCPU_ID, > > - 2ul << (GUEST_MEM_SHIFT - PAGE_SHIFT_4K), > > + (2 * guest_memory_bytes) >> PAGE_SHIFT_4K, > > guest_code); > > > > guest_page_size = vm_get_page_size(vm); > > - /* > > - * A little more than 1G of guest page sized pages. Cover the > > - * case where the size is not aligned to 64 pages. > > - */ > > - guest_num_pages = (1ul << (GUEST_MEM_SHIFT - > > - vm_get_page_shift(vm))) + 16; > > + > > + TEST_ASSERT(guest_memory_bytes % guest_page_size == 0, > > + "Guest memory size is not guest page size aligned."); > > + > > + guest_num_pages = guest_memory_bytes / guest_page_size; > > + > > #ifdef __s390x__ > > /* Round up to multiple of 1M (segment size) */ > > guest_num_pages = (guest_num_pages + 0xff) & ~0xffUL; > > #endif > > + /* > > + * If there should be more memory in the guest test region than there > > + * can be pages in the guest, it will definitely cause problems. > > + */ > > + TEST_ASSERT(guest_num_pages < vm_get_max_gfn(vm), > > + "Requested more guest memory than address space allows.\n" > > + " guest pages: %lx max gfn: %lx\n", > > + guest_num_pages, vm_get_max_gfn(vm)); > > > > host_page_size = getpagesize(); > > - host_num_pages = (guest_num_pages * guest_page_size) / host_page_size + > > - !!((guest_num_pages * guest_page_size) % > > - host_page_size); > > + TEST_ASSERT(guest_memory_bytes % host_page_size == 0, > > + "Guest memory size is not host page size aligned."); > > + host_num_pages = guest_memory_bytes / host_page_size; > > > > guest_test_phys_mem = (vm_get_max_gfn(vm) - guest_num_pages) * > > guest_page_size; > > @@ -381,7 +389,8 @@ static void help(char *name) > > int i; > > > > puts(""); > > - printf("usage: %s [-h] [-m mode] [-u] [-d uffd_delay_usec]\n", name); > > + printf("usage: %s [-h] [-m mode] [-u] [-d uffd_delay_usec]\n" > > + " [-b bytes test memory]\n", name); > > printf(" -m: specify the guest mode ID to test\n" > > " (default: test all supported modes)\n" > > " This option may be used multiple times.\n" > > @@ -395,6 +404,8 @@ static void help(char *name) > > printf(" -d: add a delay in usec to the User Fault\n" > > " FD handler to simulate demand paging\n" > > " overheads. Ignored without -u.\n"); > > + printf(" -b: specify the number of bytes of memory which should be\n" > > + " allocated to the guest.\n"); > > Can we input in megabytes instead? And also it might be nice to output the > default size here. I added a little function to parse size arguments so users can specify 2M or 7G. I also changed this to print the default value. > > > puts(""); > > exit(0); > > } > > @@ -402,6 +413,7 @@ static void help(char *name) > > int main(int argc, char *argv[]) > > { > > bool mode_selected = false; > > + uint64_t guest_memory_bytes = DEFAULT_GUEST_TEST_MEM_SIZE; > > unsigned int mode; > > int opt, i; > > bool use_uffd = false; > > @@ -414,7 +426,7 @@ int main(int argc, char *argv[]) > > vm_guest_mode_params_init(VM_MODE_P40V48_4K, true, true); > > #endif > > > > - while ((opt = getopt(argc, argv, "hm:ud:")) != -1) { > > + while ((opt = getopt(argc, argv, "hm:ud:b:")) != -1) { > > switch (opt) { > > case 'm': > > if (!mode_selected) { > > @@ -435,6 +447,8 @@ int main(int argc, char *argv[]) > > TEST_ASSERT(uffd_delay >= 0, > > "A negative UFFD delay is not supported."); > > break; > > + case 'b': > > + guest_memory_bytes = strtoull(optarg, NULL, 0); > > Missing break. So it doesn't look like this was tested. Woops, you're right, I must not have tested this commit. The break is added in commit 6/8 and I only tested at the end of the series. I'll have the break in this commit in the next version of this series. > > > case 'h': > > default: > > help(argv[0]); > > @@ -448,7 +462,7 @@ int main(int argc, char *argv[]) > > TEST_ASSERT(vm_guest_mode_params[i].supported, > > "Guest mode ID %d (%s) not supported.", > > i, vm_guest_mode_string(i)); > > - run_test(i, use_uffd, uffd_delay); > > + run_test(i, use_uffd, uffd_delay, guest_memory_bytes); > > } > > > > return 0; > > -- > > 2.24.1.735.g03f4e72817-goog > > > > Thanks, > drew >