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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 D59C7C531DC for ; Fri, 16 Aug 2024 18:41:02 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.778753.1188761 (Exim 4.92) (envelope-from ) id 1sf1sV-0004jA-5B; Fri, 16 Aug 2024 18:40:47 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 778753.1188761; Fri, 16 Aug 2024 18:40:47 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sf1sV-0004j3-2a; Fri, 16 Aug 2024 18:40:47 +0000 Received: by outflank-mailman (input) for mailman id 778753; Fri, 16 Aug 2024 18:40:46 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sf1sU-0004ix-1Z for xen-devel@lists.xenproject.org; Fri, 16 Aug 2024 18:40:46 +0000 Received: from mail-lf1-x130.google.com (mail-lf1-x130.google.com [2a00:1450:4864:20::130]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 0b5ea376-5bff-11ef-8776-851b0ebba9a2; Fri, 16 Aug 2024 20:40:43 +0200 (CEST) Received: by mail-lf1-x130.google.com with SMTP id 2adb3069b0e04-52f04b4abdcso2876855e87.2 for ; Fri, 16 Aug 2024 11:40:43 -0700 (PDT) Received: from localhost ([185.25.67.249]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a83838eeedasm292198966b.94.2024.08.16.11.40.42 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Aug 2024 11:40:42 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 0b5ea376-5bff-11ef-8776-851b0ebba9a2 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloud.com; s=cloud; t=1723833643; x=1724438443; darn=lists.xenproject.org; h=in-reply-to:references:subject:cc:to:from:message-id:date :content-transfer-encoding:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=txNU6K5Z94jOa7kGMNFjkKteyqZwZ1+WnjUo52dlHnI=; b=DLw9VKm0cTlRO9lcasAHtliJu2fdR6sLqMzYgdqxi0M60y+6YoMWFyS7zYePSaGVlC 4mcFw6HeDL4hP6E3U7pj1dePiSTBQxyiK9spx9Donb95oAFqGo2nBCNvUpFygU4v6/v3 Mk3FM0NrH9LF4HCUOJ/8UYmHX25PoWFP0ArIc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723833643; x=1724438443; h=in-reply-to:references:subject:cc:to:from:message-id:date :content-transfer-encoding:mime-version:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=txNU6K5Z94jOa7kGMNFjkKteyqZwZ1+WnjUo52dlHnI=; b=M3AWb4rkg4EXw9wEAhCntZWBBi8TjiherTdyahECdlm7qOyD3m8CKviIHjcIziDydG gxQd/sbrq6Ieyh7JsAqLkFVSNs+YnvzVUsa45JBPn4he/WVT+xi5YKDx9uZzLFef8Hg9 PLR+N81DSA7yD3UFalaWv12jwX+eXv5MKFV4+Fm3Ek/QCerHqPRKR1stpfl2xxK8YgEa ngQJDPvoYQkgCU/1wFiRr0kjZzm0+LgArEUiORmFmuivYaR77gpxAXEo0Nd1L5av2GdG aVHIRGWrdN23QNKxzQHcOovbZ5A/spVG1pozjXEBdb2e3FHXtF4gtMOvrQb7s2VAaZFG Zv1Q== X-Forwarded-Encrypted: i=1; AJvYcCXl6Gq00+/DSlNaznJ4BUUTJ//TOV0TxCtnC7xGhmTL6iYyZUV3MMZXLg/z8rRjMrQQZOcmK0c9gzQ=@lists.xenproject.org X-Gm-Message-State: AOJu0YwZgnnA2yfGrX9B8yHvliyttSQrCZx3zExfFuDFidZMVrqsUguT WwMdu4y4eULlsRXBUxJEGWdx3a0tao9nxRC+9XHtX1rQJROyVMlv0G2twcrRFtI= X-Google-Smtp-Source: AGHT+IHFpOp2NvrWKrkf2baSt+dWZuQ3GgoiTu8U54rKCb10A8hcm9G0D9PWN+SnNiixPqmNSrZx6g== X-Received: by 2002:a05:6512:3082:b0:52f:cd03:a847 with SMTP id 2adb3069b0e04-5331c6f47f1mr2061371e87.61.1723833643109; Fri, 16 Aug 2024 11:40:43 -0700 (PDT) Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Fri, 16 Aug 2024 19:40:40 +0100 Message-Id: From: "Alejandro Vallejo" To: "Roger Pau Monne" , Cc: "Jan Beulich" , "Andrew Cooper" Subject: Re: [PATCH 16/22] x86/mm: introduce a per-CPU L3 table for the per-domain slot X-Mailer: aerc 0.17.0 References: <20240726152206.28411-1-roger.pau@citrix.com> <20240726152206.28411-17-roger.pau@citrix.com> In-Reply-To: <20240726152206.28411-17-roger.pau@citrix.com> On Fri Jul 26, 2024 at 4:22 PM BST, Roger Pau Monne wrote: > So far L4 slot 260 has always been per-domain, in other words: all vCPUs = of a > domain share the same L3 entry. Currently only 3 slots are used in that = L3 > table, which leaves plenty of room. > > Introduce a per-CPU L3 that's used the the domain has Address Space Isola= tion > enabled. Such per-CPU L3 gets currently populated using the same L3 entr= ies > present on the per-domain L3 (d->arch.perdomain_l3_pg). > > No functional change expected, as the per-CPU L3 is always a copy of the > contents of d->arch.perdomain_l3_pg. > > Note that all the per-domain L3 entries are populated at domain create, a= nd > hence there's no need to sync the state of the per-CPU L3 as the domain w= on't > yet be running when the L3 is modified. > > Signed-off-by: Roger Pau Monn=C3=A9 Still scratching my head with the details on this, but in general I'm utter= ly confused whenever I read per-CPU in the series because it's not obvious whi= ch CPU (p or v) I should be thinking about. A general change that would help a= lot is to replace every instance of per-CPU with per-vCPU or per-pCPU as needed= . Cheers, Alejandro