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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57AB2C77B73 for ; Wed, 19 Apr 2023 11:40:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DDC25900002; Wed, 19 Apr 2023 07:40:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D8C4A8E0001; Wed, 19 Apr 2023 07:40:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C54BF900002; Wed, 19 Apr 2023 07:40:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id B79718E0001 for ; Wed, 19 Apr 2023 07:40:25 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 7CDD9A024C for ; Wed, 19 Apr 2023 11:40:25 +0000 (UTC) X-FDA: 80697947610.24.A7892A7 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf02.hostedemail.com (Postfix) with ESMTP id 1B6C180011 for ; Wed, 19 Apr 2023 11:40:22 +0000 (UTC) Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=RStd1pjj; spf=pass (imf02.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1681904423; h=from:from:sender: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:dkim-signature; bh=d94kMyGvyZL17XK7WKirw3h92EHgohkqQ/7jeLjX7+U=; b=k7/w1nb8gOayuyD2fklFmWSDCgtgzQIq6IkUfr36RshCUil8LMRO/NiJ0i0luVvaE7qmbF hVZ+5AZ3tDr5u0EUC1OnwJHDwX0NOM2MW4TbB21+zwnIlLaPIzVSK9PAWgD2xTxchyu0j8 D/cBuf46eIi9FtTjhO7IeJtmrhXhVaE= ARC-Authentication-Results: i=1; imf02.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=RStd1pjj; spf=pass (imf02.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1681904423; a=rsa-sha256; cv=none; b=AILRU+pmbgr+OoUb4I50nB4/uHtJBh1JEgFi9Y1tU2m+ipw0oPyCe/TkkfSa74RVMZjNTD qk8MggdoCAc9fbVOA0k6j0H4Vxo9ySt1RS8PfgOHUf5QPpt5iPM85XWsYxQjbU4Y1qPivB K9t0DAYVoWqTLnpZ8r0GRPXfj9beVks= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681904422; 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=d94kMyGvyZL17XK7WKirw3h92EHgohkqQ/7jeLjX7+U=; b=RStd1pjj0sWU/Vfgzkb5oQpz76DGWeIy1DNBZwXsburYYmYqT9uXVlDjILVkIWbnAiuiAw JGTWghniQTXJgmip2M4EztVy68M0lUinzw47oihJTa1z7B4H3ZjL2Nuip5xSOMwfLGyPYY ClgeFgPqE7KQQudXTr/0TZlkWpsJnXc= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-583-4d7RjBq7MHO4zpJHq7vC8A-1; Wed, 19 Apr 2023 07:40:21 -0400 X-MC-Unique: 4d7RjBq7MHO4zpJHq7vC8A-1 Received: by mail-wm1-f69.google.com with SMTP id a19-20020a05600c349300b003f17146a8deso1009662wmq.3 for ; Wed, 19 Apr 2023 04:40:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681904420; x=1684496420; h=content-transfer-encoding:in-reply-to:organization:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=d94kMyGvyZL17XK7WKirw3h92EHgohkqQ/7jeLjX7+U=; b=mAtT5LZR8YXa5caxzfGXxmSUOPAhG9eoqOGA5UlhoYLHEdQMu6fs4ycgC8Sd8S8r5G HfqES9FpvjO/cf+Kyf6H/l7Mj+HwWaK1F9fgC0yQotapIbUyY/FGru0AzUihh4PwKPkh qYJUK2gOKMwiLoYVxCY6zWkUFEzHvx6ITV/rzkMY/XOF1ZNDSYa7PYf9TgAKXLnwZjcp 0sZdliqiap5UCF89V3HhZVGPE/XimyqVAVlwPaASZGmi/ql0tcpNJCuI7ugJ/P3Ym45+ caufQHZYhMSk14C7Ch03gBaO4vrLDFeXxHGgTZHdWaCg2WE/qFzd0ze6DgjcR1SYGWJj oSbg== X-Gm-Message-State: AAQBX9f2tNI+0CdNwbh46ZUEDcsJXJjK4TPPqyLJqApBb9RZSAAuBdE7 64NeapdPLu7Yk+lXwV+yQomwpjXa5/Acg/30mpetsxU4if0vexhIj6OSq7+uE/qGJef7A/JAcJ1 PG1AhpVMMxRA= X-Received: by 2002:a05:600c:ac4:b0:3f1:6ead:34fe with SMTP id c4-20020a05600c0ac400b003f16ead34femr11020933wmr.26.1681904419994; Wed, 19 Apr 2023 04:40:19 -0700 (PDT) X-Google-Smtp-Source: AKy350YgwHEzMmaB06GSpMni85LlmtPmKFDMOVPBAvCAxul+liaggVeQse0nWLU2InZIpdyZOr8tAg== X-Received: by 2002:a05:600c:ac4:b0:3f1:6ead:34fe with SMTP id c4-20020a05600c0ac400b003f16ead34femr11020914wmr.26.1681904419705; Wed, 19 Apr 2023 04:40:19 -0700 (PDT) Received: from ?IPV6:2003:cb:c70b:7b00:7c52:a5fa:8004:96fd? (p200300cbc70b7b007c52a5fa800496fd.dip0.t-ipconnect.de. [2003:cb:c70b:7b00:7c52:a5fa:8004:96fd]) by smtp.gmail.com with ESMTPSA id d17-20020a056000115100b002fa6929eb83sm7870151wrx.21.2023.04.19.04.40.18 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 19 Apr 2023 04:40:19 -0700 (PDT) Message-ID: <743c4686-43aa-15fa-5989-af9a43a783f9@redhat.com> Date: Wed, 19 Apr 2023 13:40:18 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 Subject: Re: [PATCH v1 3/3] mm/ksm: move disabling KSM from s390/gmap code to KSM code To: Janosch Frank , linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-s390@vger.kernel.org, linux-kselftest@vger.kernel.org, Andrew Morton , Stefan Roesch , Rik van Riel , Johannes Weiner , Michal Hocko , Christian Borntraeger , Claudio Imbrenda , Heiko Carstens , Vasily Gorbik , Sven Schnelle , Shuah Khan References: <20230418051342.1919757-1-shr@devkernel.io> <20230418152849.505124-1-david@redhat.com> <20230418152849.505124-4-david@redhat.com> <42df1c58-f0bf-5dd8-03db-ee2fa28d7c1b@linux.ibm.com> From: David Hildenbrand Organization: Red Hat In-Reply-To: <42df1c58-f0bf-5dd8-03db-ee2fa28d7c1b@linux.ibm.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: 3fzia1umo1to1o7szepqh64ckk5gyc4o X-Rspamd-Queue-Id: 1B6C180011 X-HE-Tag: 1681904422-838106 X-HE-Meta: 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 IYDxP4V/ nceSVIWvO5tJ90Cqj4jATaSVecZHL+mxEtU2bWEXPzwu8d3LcAXFDqTtGddyLLy2ZJIiOb73Bp3QBf29/rPmNOUk2UV4KIKBkvuePhlNUsUJKKHlij9uV0ojkMWphZrxdFVl/XP3QZ6IUBz9oTOzp6juFfe05pQtudOK4c5eWeYDIZKlRn/uh0yxu9PQ4cw3cskFIGzBGXrEDGQGZmEIV17xijctxHOphQwWTtDlepZALATcLgkpTOgjhlMYnDMC5+5YPrAJyVArZmcQlTQtryO5V9otGYbs+vCo+DmWV5g2ACIhqf3HPcHdIS0x/R4wJFyiBK3CKQA91X+oh5qATLsMOsavjHim04GsnkQnpP7R2vi+Uq4xrgPanRaeXHX5GQ1qIy3oBcLV0rWcbc5cRJEFiQzUAhdQ0n7xuFTYiap7I4U103MmnMDHh77YKWMb6OkTAcCvcYDe3r3MakZ6VjD1kSYgyIv817NaWqJTqnN9G96o= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 19.04.23 13:39, Janosch Frank wrote: > On 4/18/23 17:28, David Hildenbrand wrote: >> Let's factor out actual disabling of KSM. The existing >> "mm->def_flags &= ~VM_MERGEABLE;" was essentially a NOP and can be dropped, >> because def_flags should never include VM_MERGEABLE. Note that we don't >> currently prevent re-enabling KSM. >> >> This should now be faster in case KSM was never enabled, because we only >> conditionally iterate all VMAs. Further, it certainly looks cleaner. >> >> Signed-off-by: David Hildenbrand >> --- >> arch/s390/mm/gmap.c | 20 +------------------- >> include/linux/ksm.h | 6 ++++++ >> mm/ksm.c | 11 +++++++++++ >> 3 files changed, 18 insertions(+), 19 deletions(-) >> >> diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c >> index 0949811761e6..dfe905c7bd8e 100644 >> --- a/arch/s390/mm/gmap.c >> +++ b/arch/s390/mm/gmap.c >> @@ -2585,30 +2585,12 @@ EXPORT_SYMBOL_GPL(s390_enable_sie); >> >> int gmap_mark_unmergeable(void) >> { >> - struct mm_struct *mm = current->mm; >> - struct vm_area_struct *vma; >> - unsigned long vm_flags; >> - int ret; >> - VMA_ITERATOR(vmi, mm, 0); >> - >> /* >> * Make sure to disable KSM (if enabled for the whole process or >> * individual VMAs). Note that nothing currently hinders user space >> * from re-enabling it. >> */ > > Is that still true? Yes. We'd need another per-MM bit to stop it from getting re-enabled. > > My KSM knowledge is nearly zero but from what I can see the patch looks > ok to me: > Acked-by: Janosch Frank Thanks! -- Thanks, David / dhildenb