From patchwork Tue May 28 16:15:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Privoznik X-Patchwork-Id: 13677017 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0EBA6C25B7E for ; Tue, 28 May 2024 16:16:26 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sBzTw-0003Tp-Gj; Tue, 28 May 2024 12:15:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sBzTu-0003T2-NZ for qemu-devel@nongnu.org; Tue, 28 May 2024 12:15:22 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sBzTt-0001iy-6a for qemu-devel@nongnu.org; Tue, 28 May 2024 12:15:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1716912920; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=daoFMEShlBnxsuXyynDFlX5cEjXfkBVlaBMEp7a2wDo=; b=GkRYAmbQJer3+Vo0UQcpTJcOmCZ0whaPHIBkqXl/UU93wmO8lgLY6lCs9TMKU4KRmiz/BM 9ndPYXpVguXu51v+stx8w7btOFXCPZDMahHFx7zro3NlPjZkvCtR2wecJPAbYSdT68EhIb 2Ljnu0h5DlnfdhAz2U1hOB+oCFb88Hw= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-615-Q6iOy824MzGkPufIyvQsyw-1; Tue, 28 May 2024 12:15:18 -0400 X-MC-Unique: Q6iOy824MzGkPufIyvQsyw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 528BE185A780 for ; Tue, 28 May 2024 16:15:18 +0000 (UTC) Received: from maggie.brq.redhat.com (unknown [10.43.3.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7FD73C15BC3; Tue, 28 May 2024 16:15:17 +0000 (UTC) From: Michal Privoznik To: qemu-devel@nongnu.org Cc: david@redhat.com, imammedo@redhat.com Subject: [PATCH 3/3] backends/hostmem: Round up memory size for qemu_madvise() and mbind() Date: Tue, 28 May 2024 18:15:09 +0200 Message-ID: In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=mprivozn@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.034, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Simple reproducer: qemu.git $ ./build/qemu-system-x86_64 \ -m size=8389632k,slots=16,maxmem=25600000k \ -object '{"qom-type":"memory-backend-file","id":"ram-node0","mem-path":"/hugepages2M/","prealloc":true,"size":8590983168,"host-nodes":[0],"policy":"bind"}' \ -numa node,nodeid=0,cpus=0,memdev=ram-node0 With current master I get: qemu-system-x86_64: cannot bind memory to host NUMA nodes: Invalid argument The problem is that memory size (8193MiB) is not an integer multiple of underlying pagesize (2MiB) which triggers a check inside of mbind(), since we can't really set policy just to a fraction of a page. As qemu_madvise() has the same expectation, round size passed to underlying pagesize. Signed-off-by: Michal Privoznik --- backends/hostmem.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/backends/hostmem.c b/backends/hostmem.c index 1a6fd1c714..9b727699f6 100644 --- a/backends/hostmem.c +++ b/backends/hostmem.c @@ -179,6 +179,8 @@ static void host_memory_backend_set_merge(Object *obj, bool value, Error **errp) void *ptr = memory_region_get_ram_ptr(&backend->mr); uint64_t sz = memory_region_size(&backend->mr); + sz = ROUND_UP(sz, qemu_ram_pagesize(backend->mr.ram_block)); + if (qemu_madvise(ptr, sz, value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE)) { warn_report("Couldn't change property 'merge' on '%s': %s", @@ -208,6 +210,8 @@ static void host_memory_backend_set_dump(Object *obj, bool value, Error **errp) void *ptr = memory_region_get_ram_ptr(&backend->mr); uint64_t sz = memory_region_size(&backend->mr); + sz = ROUND_UP(sz, qemu_ram_pagesize(backend->mr.ram_block)); + if (qemu_madvise(ptr, sz, value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP)) { warn_report("Couldn't change property 'dump' on '%s': %s", @@ -344,6 +348,13 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp) ptr = memory_region_get_ram_ptr(&backend->mr); sz = memory_region_size(&backend->mr); + /* + * Round up size to be an integer multiple of pagesize, because + * both madvise() and mbind() does not really like setting + * advice/policy to just a fraction of a page. + */ + sz = ROUND_UP(sz, qemu_ram_pagesize(backend->mr.ram_block)); + if (backend->merge && qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE)) { warn_report("Couldn't set property 'merge' on '%s': %s",