From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A2D539AD5; Tue, 2 Apr 2024 07:33:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712043221; cv=none; b=qi9UEs2ex1woO47XIbNat0xf8nQZ1jYN9R+rqCItDbPoPWuRPYXJl3L+NTLciK0UGe4G/1zRptF17FrmiTkYNlE2t8YyTCtyi4RGNNRS/xYGTdp61/PIbSr+gXK0nXHnsgYwGTl+UJ7OLZBlcLy8TuusSbyY3v8XRC/RZDZcjp0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712043221; c=relaxed/simple; bh=m/HmUPqKtAU2Uzx9nZeyjvyqOP6z3AWH/L98dSBa2eE=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=j+nVhyR47v7rwaZyHSUYstn6pA4io4uaBrkAzT/SOnAWWxam6nzHbs9Cb9BqsJkvff9lTafSYhhCskB7p6xsK9Vg67LD5ATSAa0poFfgtPDUd0x/qGYGjxJebVxIXAZ4Gv+3al41ZDJ0Kpa7Ma/DvgjMLbg8szeZaNF9lZnEeuE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=q45gGveN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="q45gGveN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3DFEC433F1; Tue, 2 Apr 2024 07:33:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1712043220; bh=m/HmUPqKtAU2Uzx9nZeyjvyqOP6z3AWH/L98dSBa2eE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=q45gGveNzJJNmszpvI5WF3tatmQxt0nBrDNzXVfcUvtoKdEArlvelGXMiNea3muXS AwsWrkMjm2FR4+yXI6W5figU2Hc9V21fJTdwGugb+Eb/5lnFimTnLQZ4r6hMgIJkaW 7NtTQTNsXB3hRf4d0NIa+qRqyyoxfl84SLzLpK33CGpGizwSVyKl03yHW8+Nyo4pdB I3OZQdjtoeD9WRNWs0VoQGpgdbqMq/HxtyDPjR5D2HLH6QkrBBi+Dj3s/u49291KC8 yawsn9G89FH1p6za4/EEB17IMDpni4jtNxIbUIi+eFdq8Xh4zhEzzIbL3bOzXRcD7z XMa9VuwynDwrw== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1rrYeI-000bjD-4I; Tue, 02 Apr 2024 08:33:38 +0100 Date: Tue, 02 Apr 2024 08:33:37 +0100 Message-ID: <86bk6sz0a6.wl-maz@kernel.org> From: Marc Zyngier To: Yu Zhao Cc: James Houghton , Andrew Morton , Paolo Bonzini , David Matlack , Oliver Upton , Sean Christopherson , Jonathan Corbet , James Morse , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Shaoqin Huang , Gavin Shan , Ricardo Koller , Raghavendra Rao Ananta , Ryan Roberts , David Rientjes , Axel Rasmussen , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH v3 6/7] KVM: arm64: Participate in bitmap-based PTE aging In-Reply-To: References: <20240401232946.1837665-1-jthoughton@google.com> <20240401232946.1837665-7-jthoughton@google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/29.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: yuzhao@google.com, jthoughton@google.com, akpm@linux-foundation.org, pbonzini@redhat.com, dmatlack@google.com, oliver.upton@linux.dev, seanjc@google.com, corbet@lwn.net, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, shahuang@redhat.com, gshan@redhat.com, ricarkol@google.com, rananta@google.com, ryan.roberts@arm.com, rientjes@google.com, axelrasmussen@google.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Tue, 02 Apr 2024 05:06:56 +0100, Yu Zhao wrote: >=20 > On Mon, Apr 1, 2024 at 7:30=E2=80=AFPM James Houghton wrote: > > > > Participate in bitmap-based aging while grabbing the KVM MMU lock for > > reading. Ideally we wouldn't need to grab this lock at all, but that > > would require a more intrustive and risky change. > ^^^^^^^^^^ intrusive > This sounds subjective -- I'd just present the challenges and let > reviewers make their own judgements. Quite the opposite. This sort of comment actually indicates that the author has at least understood some of the complexity behind the proposed changes. It is a qualitative comment that conveys useful information to reviewers, and even more to the maintainers of this code. That's the difference between a human developer and a bot, and I'm not overly fond of bots. M. --=20 Without deviation from the norm, progress is not possible. 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 96EBBCD1284 for ; Tue, 2 Apr 2024 07:34:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Subject:Cc:To:From:Message-ID:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=p1kjFx+4Nz/KH92zYWhFWZ/IavzAO55atKEwbPo2GZk=; b=Wsvwj1iZAoieIS 2mtqP/XXmXbt19iMugYGz5YJXdv2TthBt/PYYNaAJvgwsNri0xZS+O66D++tslfIYM6f1MZeWTGD5 QqPiMhAdTMa1regZqrn8XQGX/0eEyZ0lzbYIQB9f0VLbradWGSizNfkjTUVJrsb/vTeMLRepIZE+Q D3761tM5NGMrLM86a+Ic2hUeoueZlfQoxlUv/pG/tYAf6+Vn292BFNS/BetUTego6WzTxpezSJMuw iGrtLpy6niU50RgrwCpyJvA4ctHCCmclUwE7XskRSh85ieJJcRLVX92HSFcFx39B7LGq9K79Ibstv /ylkeo/hB3pFfbuyXWPw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rrYeR-0000000A5QP-2xqH; Tue, 02 Apr 2024 07:33:47 +0000 Received: from sin.source.kernel.org ([2604:1380:40e1:4800::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rrYeO-0000000A5Pa-2ruR for linux-arm-kernel@lists.infradead.org; Tue, 02 Apr 2024 07:33:46 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id A2543CE1AC8; Tue, 2 Apr 2024 07:33:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3DFEC433F1; Tue, 2 Apr 2024 07:33:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1712043220; bh=m/HmUPqKtAU2Uzx9nZeyjvyqOP6z3AWH/L98dSBa2eE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=q45gGveNzJJNmszpvI5WF3tatmQxt0nBrDNzXVfcUvtoKdEArlvelGXMiNea3muXS AwsWrkMjm2FR4+yXI6W5figU2Hc9V21fJTdwGugb+Eb/5lnFimTnLQZ4r6hMgIJkaW 7NtTQTNsXB3hRf4d0NIa+qRqyyoxfl84SLzLpK33CGpGizwSVyKl03yHW8+Nyo4pdB I3OZQdjtoeD9WRNWs0VoQGpgdbqMq/HxtyDPjR5D2HLH6QkrBBi+Dj3s/u49291KC8 yawsn9G89FH1p6za4/EEB17IMDpni4jtNxIbUIi+eFdq8Xh4zhEzzIbL3bOzXRcD7z XMa9VuwynDwrw== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1rrYeI-000bjD-4I; Tue, 02 Apr 2024 08:33:38 +0100 Date: Tue, 02 Apr 2024 08:33:37 +0100 Message-ID: <86bk6sz0a6.wl-maz@kernel.org> From: Marc Zyngier To: Yu Zhao Cc: James Houghton , Andrew Morton , Paolo Bonzini , David Matlack , Oliver Upton , Sean Christopherson , Jonathan Corbet , James Morse , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. 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