From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F08043C4166 for ; Tue, 16 Jun 2026 05:00:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781586013; cv=none; b=HNhrcwq+OWPEc5xHQ0qPFt3hqr+5QvqugaIxGgZf4Y7szLt/izU15JT92zNVpH5d/7xc0YHLaLilGgsEAahhauDdT9NfSmYYk+/WtxMXbxacJ9/gXpKMCOwD2Ac77mW1An3GyU9BxrFV87gp2Oo2lBeHp8ZWVLNL7FCqlkgJxx0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781586013; c=relaxed/simple; bh=pKqht8xBTdJPB8coISoY8X6SJ1c7ZZAUQnZN+qy2n2I=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cNKAjrPy02Afvn1RCVCqNLu7eO0GK7cQgn1J/ujSQIcmrAnN8p7VIv7iUrUPq+6cL3+g/p7AYPSMQzJraTjWXkOb2pkU6qcq1lQOp6GIY9e/g8hFN+L3FEcm5ZEgXzIiT35xUyxCzjTMk0S08ZGFTWVqVy/OC067f2FZOEQAA6s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=p/tq9cRX; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="p/tq9cRX" 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 8EADA3D4B; Mon, 15 Jun 2026 22:00:06 -0700 (PDT) Received: from localhost (a079125.arm.com [10.164.21.37]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 833AF3F915; Mon, 15 Jun 2026 22:00:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1781586011; bh=pKqht8xBTdJPB8coISoY8X6SJ1c7ZZAUQnZN+qy2n2I=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=p/tq9cRXU7CTPJIcLoxIeuxSFMhB2z8/9qBRupZLiPMX8aupEXzRIuKsaVG/0p6j3 x8VUhBLZ0ZmzVaZEPfTOs/czMpJAlLQQKhjmuCP2nq9cZdGAqS1kfog+nv9PhY494T PxtJGZctd9VTRa78lBcu/41Y5qW6Ti0ctIr/FShg= Date: Tue, 16 Jun 2026 10:30:07 +0530 From: Linu Cherian To: Will Deacon Cc: Ryan Roberts , Catalin Marinas , Kevin Brodsky , Anshuman Khandual , Yang Shi , Mark Rutland , Huang Ying , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, shameerali.kolothum.thodi@huawei.com Subject: Re: [PATCH v2] arm64: tlbflush: Don't broadcast if mm was only active on local cpu Message-ID: References: <20260523134710.3827956-1-linu.cherian@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hi, On Mon, Jun 15, 2026 at 03:43:41PM +0100, Will Deacon wrote: > On Mon, Jun 15, 2026 at 12:21:19PM +0100, Ryan Roberts wrote: > > On 14/06/2026 12:04, Will Deacon wrote: > > > On Sat, May 23, 2026 at 07:17:10PM +0530, Linu Cherian wrote: > > >> From: Ryan Roberts > > >> > > >> Testing with 7.1-rc4 : > > >> +-----------------------+---------------------------------------------------+-------------+ > > >> | Benchmark | Result Class | Improvement| > > >> +=======================+===================================================+=============+ > > >> | perf/syscall | fork (ops/sec) | (I) 3.25% | > > >> +-----------------------+---------------------------------------------------+-------------+ > > >> | pts/memtier-benchmark | Protocol: Redis Clients: 100 Ratio: 1:5 (Ops/sec) | (I) 2.70% | > > >> | | Protocol: Redis Clients: 100 Ratio: 5:1 (Ops/sec) | (I) 2.13% | > > >> +-----------------------+---------------------------------------------------+-------------+ > > > > > > I think we need a much more comprehensive set of benchmarks before we can > > > begin to consider a change like this. > > > > I believe that Linu ran a wider set of benchmarks and didn't find any > > regressions. These are just the ones that show improvement (Linu, please correct > > me and/or provide details). > > I think it's important to show the ones that suffer as well... and also > look at different configurations (e.g. preemptible settings) and different > environments (e.g. native vs in a VM). All our tests were ran on the host. Yeah, agree that other suggested configurations/environments need to be anlayzed as well. -- Thanks, Linu Cherian.