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=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 4BA9DC432C0 for ; Thu, 28 Nov 2019 17:29:36 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 15B8721787 for ; Thu, 28 Nov 2019 17:29:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Nhe31ZJp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 15B8721787 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:51370 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iaNbh-0005yZ-74 for qemu-devel@archiver.kernel.org; Thu, 28 Nov 2019 12:29:33 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:57285) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iaMec-000775-1T for qemu-devel@nongnu.org; Thu, 28 Nov 2019 11:28:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iaMeW-0002cK-QI for qemu-devel@nongnu.org; Thu, 28 Nov 2019 11:28:27 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:34841) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iaMeV-0002E5-Es for qemu-devel@nongnu.org; Thu, 28 Nov 2019 11:28:24 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1574958500; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wpoLOjdZwNkDuObU2v9krvOE3FaeA4ApFjAT/JTGTGY=; b=Nhe31ZJpujEXO7bcOrZTMvGi8Y/drblq2/dn3nYSv3N41fiPZ2Li4Ju1QeSSxyjLuGrTBs kKVJlxCMC68yELQ98GChNOoKuSzoC8O+W8icBauGrzVNkelhELfc7O1OthZTaDhDBe15HO pRxevzXu4fzqQnWhEiNNgFgruGgtZLg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-3-clBAei7TPl-kXTnsdgkfWQ-1; Thu, 28 Nov 2019 11:28:17 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 283CE800C75; Thu, 28 Nov 2019 16:28:16 +0000 (UTC) Received: from localhost (unknown [10.43.2.114]) by smtp.corp.redhat.com (Postfix) with ESMTP id 676625D6D2; Thu, 28 Nov 2019 16:28:09 +0000 (UTC) Date: Thu, 28 Nov 2019 17:28:07 +0100 From: Igor Mammedov To: =?UTF-8?B?TWFyYy1BbmRyw6k=?= Lureau Subject: Re: [PATCH 2/2] Add -mem-shared option Message-ID: <20191128172807.788e6aeb@redhat.com> In-Reply-To: <20191128141518.628245-3-marcandre.lureau@redhat.com> References: <20191128141518.628245-1-marcandre.lureau@redhat.com> <20191128141518.628245-3-marcandre.lureau@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-MC-Unique: clBAei7TPl-kXTnsdgkfWQ-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Richard Henderson , qemu-devel@nongnu.org, stefanha@redhat.com, Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, 28 Nov 2019 18:15:18 +0400 Marc-Andr=C3=A9 Lureau wrote: > Add an option to simplify shared memory / vhost-user setup. >=20 > Currently, using vhost-user requires NUMA setup such as: > -m 4G -object memory-backend-file,id=3Dmem,size=3D4G,mem-path=3D/dev/shm,= share=3Don -numa node,memdev=3Dmem >=20 > As there is no other way to allocate shareable RAM, afaik. >=20 > -mem-shared aims to have a simple way instead: -m 4G -mem-shared User always can write a wrapper script if verbose CLI is too much, and we won't have to deal with myriad permutations to maintain. Also current -mem-path/prealloc in combination with memdevs is the source of problems (as ram allocation uses 2 different paths). It's possible to fix with a kludge but I'd rather fix it properly. So during 5.0, I'm planning to consolidate -mem-path/prealloc handling around memory backend internally (and possibly deprecate them), so the only way to allocate RAM for guest would be via memdevs. (reducing number of options an globals that they use) So user who wants something non trivial could override default non-numa behavior with -object memory-backend-file,id=3Dmem,size=3D4G,mem-path=3D/dev/shm,share= =3Don \ -machine memdev=3Dmem or use any other backend that suits theirs needs. > Signed-off-by: Marc-Andr=C3=A9 Lureau > --- > exec.c | 11 ++++++++++- > hw/core/numa.c | 16 +++++++++++++++- > include/sysemu/sysemu.h | 1 + > qemu-options.hx | 10 ++++++++++ > vl.c | 4 ++++ > 5 files changed, 40 insertions(+), 2 deletions(-) >=20 > diff --git a/exec.c b/exec.c > index ffdb518535..4e53937eaf 100644 > --- a/exec.c > +++ b/exec.c > @@ -72,6 +72,10 @@ > #include "qemu/mmap-alloc.h" > #endif > =20 > +#ifdef CONFIG_POSIX > +#include "qemu/memfd.h" > +#endif > + > #include "monitor/monitor.h" > =20 > //#define DEBUG_SUBPAGE > @@ -2347,7 +2351,12 @@ RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size= , MemoryRegion *mr, > bool created; > RAMBlock *block; > =20 > - fd =3D file_ram_open(mem_path, memory_region_name(mr), &created, err= p); > + if (mem_path) { > + fd =3D file_ram_open(mem_path, memory_region_name(mr), &created,= errp); > + } else { > + fd =3D qemu_memfd_open(mr->name, size, > + F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, = errp); > + } that's what I'm mostly against, as it spills out memdev impl. details into generic code. > if (fd < 0) { > return NULL; > } > diff --git a/hw/core/numa.c b/hw/core/numa.c > index e3332a984f..6f72cddb1c 100644 > --- a/hw/core/numa.c > +++ b/hw/core/numa.c > @@ -493,7 +493,8 @@ static void allocate_system_memory_nonnuma(MemoryRegi= on *mr, Object *owner, > if (mem_path) { > #ifdef __linux__ > Error *err =3D NULL; > - memory_region_init_ram_from_file(mr, owner, name, ram_size, 0, 0= , > + memory_region_init_ram_from_file(mr, owner, name, ram_size, 0, > + mem_shared ? RAM_SHARED : 0, > mem_path, &err); this will be gone and replaced by memory region that memdev initializes. > if (err) { > error_report_err(err); > @@ -513,6 +514,19 @@ static void allocate_system_memory_nonnuma(MemoryReg= ion *mr, Object *owner, > #else > fprintf(stderr, "-mem-path not supported on this host\n"); > exit(1); > +#endif > + } else if (mem_shared) { > +#ifdef CONFIG_POSIX > + Error *err =3D NULL; > + memory_region_init_ram_from_file(mr, owner, NULL, ram_size, 0, > + RAM_SHARED, NULL, &err); > + if (err) { > + error_report_err(err); > + exit(1); > + } > +#else > + fprintf(stderr, "-mem-shared not supported on this host\n"); > + exit(1); > #endif > } else { > memory_region_init_ram_nomigrate(mr, owner, name, ram_size, &err= or_fatal); > diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h > index 80c57fdc4e..80db8465a9 100644 > --- a/include/sysemu/sysemu.h > +++ b/include/sysemu/sysemu.h > @@ -55,6 +55,7 @@ extern bool enable_cpu_pm; > extern QEMUClockType rtc_clock; > extern const char *mem_path; > extern int mem_prealloc; > +extern int mem_shared; > =20 > #define MAX_OPTION_ROMS 16 > typedef struct QEMUOptionRom { > diff --git a/qemu-options.hx b/qemu-options.hx > index 65c9473b73..4c69b03ad3 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -394,6 +394,16 @@ STEXI > Preallocate memory when using -mem-path. > ETEXI > =20 > +DEF("mem-shared", 0, QEMU_OPTION_mem_shared, > + "-mem-shared allocate shared memory\n", QEMU_ARCH_ALL) > +STEXI > +@item -mem-shared > +@findex -mem-shared > +Allocate guest RAM with shared mapping. Whether the allocation is > +anonymous or not (with -mem-path), QEMU will allocate a shared memory th= at > +can be shared by unrelated processes, such as vhost-user backends. > +ETEXI > + > DEF("k", HAS_ARG, QEMU_OPTION_k, > "-k language use keyboard layout (for example 'fr' for French)\n= ", > QEMU_ARCH_ALL) > diff --git a/vl.c b/vl.c > index 6a65a64bfd..53b1155455 100644 > --- a/vl.c > +++ b/vl.c > @@ -143,6 +143,7 @@ const char* keyboard_layout =3D NULL; > ram_addr_t ram_size; > const char *mem_path =3D NULL; > int mem_prealloc =3D 0; /* force preallocation of physical target memory= */ > +int mem_shared =3D 0; Also what happened to no more globals policy? > bool enable_mlock =3D false; > bool enable_cpu_pm =3D false; > int nb_nics; > @@ -3172,6 +3173,9 @@ int main(int argc, char **argv, char **envp) > case QEMU_OPTION_mem_prealloc: > mem_prealloc =3D 1; > break; > + case QEMU_OPTION_mem_shared: > + mem_shared =3D 1; > + break; > case QEMU_OPTION_d: > log_mask =3D optarg; > break;