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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 93127CCF9F8 for ; Thu, 6 Nov 2025 10:30:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id F13338E0009; Thu, 6 Nov 2025 05:30:03 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id EEAD48E0002; Thu, 6 Nov 2025 05:30:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E27E88E0009; Thu, 6 Nov 2025 05:30:03 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id D41BB8E0002 for ; Thu, 6 Nov 2025 05:30:03 -0500 (EST) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 87039BA763 for ; Thu, 6 Nov 2025 10:30:03 +0000 (UTC) X-FDA: 84079811886.22.69BE247 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf11.hostedemail.com (Postfix) with ESMTP id C372D4000F for ; Thu, 6 Nov 2025 10:30:01 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf11.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1762425001; a=rsa-sha256; cv=none; b=Kr7yykFU/fXEa1Jq0BzGYduw81162u45Hhik59LfaQ7S+YQsQHcz2P1Qol+brJ4MNtSZGb LnYdW81dOncZvsj8kixcR09TQg9C6vPalzZmDnqJYGK26bTzSLJ4UIuwKXYrwoVjzuKpsA hjzUgTeAYIMu4Ek6t5Q65FqIu6bFX9w= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf11.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1762425001; 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; bh=kXPFrNUNPhhkMe5rhwtRP1Qi03luuYdSthxJanNeerc=; b=hz38MN3aMBTAs8sEbhvRZYuG1DXvXkmlu3+JS02zsCgdkLqZoVTDxKcx/dbUfMqOAgSPF0 R1NBnoeiTkE7b9HIJyscLUmtA/I5m9aaSIezC1LlXtcm61vRsUSS0Uqx7eY6NjC6oNtDth IR8BhkNJIu8pJ1U8CwUi2O/Xgyl7V9Q= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B85731596; Thu, 6 Nov 2025 02:29:52 -0800 (PST) Received: from [10.1.34.75] (unknown [10.1.34.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CB9A53F66E; Thu, 6 Nov 2025 02:29:53 -0800 (PST) Message-ID: Date: Thu, 6 Nov 2025 10:29:50 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 01/12] powerpc/64s: Do not re-activate batched TLB flush To: "Ritesh Harjani (IBM)" , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Alexander Gordeev , Andreas Larsson , Andrew Morton , Boris Ostrovsky , Borislav Petkov , Catalin Marinas , Christophe Leroy , Dave Hansen , David Hildenbrand , "David S. Miller" , David Woodhouse , "H. Peter Anvin" , Ingo Molnar , Jann Horn , Juergen Gross , "Liam R. Howlett" , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , Michal Hocko , Mike Rapoport , Nicholas Piggin , Peter Zijlstra , Ryan Roberts , Suren Baghdasaryan , Thomas Gleixner , Vlastimil Babka , Will Deacon , Yeoreum Yun , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org, Venkat Rao Bagalkote References: <20251029100909.3381140-1-kevin.brodsky@arm.com> <20251029100909.3381140-2-kevin.brodsky@arm.com> <87qzud42n1.ritesh.list@gmail.com> Content-Language: en-GB From: Kevin Brodsky In-Reply-To: <87qzud42n1.ritesh.list@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: C372D4000F X-Stat-Signature: 5eskhmn6pfj3hjthpcuia7ku5wacuo7d X-HE-Tag: 1762425001-75779 X-HE-Meta: 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 ffe51KF/ Fa57h92rYQg+kw/1FAOJZLkSr/9kxIbJwX8eVlBJHq0/6rjsuW3484IOWPy0jk3SU3kpp4mn4wo2TI5jnpxlzmo+Qo4zoQMA1vm6MJoo5C8RZAtaBKZplY6MjLEc/njohhNPV/C851v2IodYPVahMSVCTQwOulDssSvM7UIsikNkcrOJxf5S61Py8vK3tGgsrP/M3jremIzAg7padrDA5b5olAeQu8RHv4jba4F/DJc82qMPk13dzhfhaFH06tFrsjycG+GakF/JZY4hL18mPs+QCB8j8Cq96kd+EjY1yPCYP9CmPGzG8UFhNKoru3gHpmr/f 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: List-Subscribe: List-Unsubscribe: On 05/11/2025 02:46, Ritesh Harjani (IBM) wrote: > Kevin Brodsky writes: > >> From: Alexander Gordeev >> >> Since commit b9ef323ea168 ("powerpc/64s: Disable preemption in hash >> lazy mmu mode") a task can not be preempted while in lazy MMU mode. >> Therefore, the batch re-activation code is never called, so remove it. >> >> Signed-off-by: Alexander Gordeev >> Signed-off-by: Kevin Brodsky >> --- >> arch/powerpc/include/asm/thread_info.h | 2 -- >> arch/powerpc/kernel/process.c | 25 ------------------------- >> 2 files changed, 27 deletions(-) >> > Since the commit referenced in above disables the preemption in > arch_enter_lazy_mmu(), so the expectation is that we will never be > context switched while in lazy_mmu, hence the code changes in > switch_to() around __flush_tlb_pending() should ideally never be called. Correct, that's the idea. > With this analysis - the patch looks good to me. I will give this entire > patch series a try on Power HW with Hash mmu too (which uses lazy mmu and > let you know the results of that)! That'd be very appreciated, thanks a lot! > For this patch please feel free to add: > Reviewed-by: Ritesh Harjani (IBM) > > > CC: Venkat who also runs CI on linux Power HW for upstream testing :) Ack, will Cc you both in the next version. - Kevin