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 B40BB38B127 for ; Tue, 12 May 2026 09:02:27 +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=1778576547; cv=none; b=rWJYwkW8xda1GUPlzPtfE36gDiiiaIzsvmmQHM5kUts94imrQTZKzsNsSpmPXd7zKYP9ZuCpuBKHStZtwIkR+PEdHlCyzFDqf1CZ2247cFkRGrS6nvNRBjFgbFrdEnuOmW3JMbqHs5uYuzgwVjn4hoxjaTYOe6RRY6r2m6eCqb8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778576547; c=relaxed/simple; bh=nUSqbg2QVpAxEQfFRfBvRGZgoisTakpc2RR4Y3RGvL0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=jExCz7GP5bd7KV+OYg08Qd4asW/bEKIQKEjSGIZOBss8gViCEHab8CA6B6Q7jl/XP5y+UoR8U3t+lol9vhH2hX0jNkPTlwJOV9znFMjOF1jN2ANeCcn6iNpDCa5rsiueusk8fWxUexQ7BCBjNeC8p6M8N7k1eytYjYsDw6ynWmo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=D2vfH1t+; 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="D2vfH1t+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A6BAC2BCB0; Tue, 12 May 2026 09:02:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778576547; bh=nUSqbg2QVpAxEQfFRfBvRGZgoisTakpc2RR4Y3RGvL0=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=D2vfH1t+2SNLEgNYgnXizamNj0nQQH2BWDkarlQyHg1HyCU4sppZw/kxeq6xPJN9l d0h8/Z+x4qKdbYmA60Be2WbX4Ha7Y3bmwfapyGLLWDqIyVqGJVLDKFJeGsVvBSRZ2s ICeX+MoOai2D9Jzho7z9SdmkMMrSupJyhkbQXfjJmmU5u6jq9jVq6dfulgvG1G/aWU nZMEV19yEQrczoFyQd0RDQQsJ81Xc8pMtSWtSbtgycDk6SA2S7Cymsd6UQl7Ix9Jkq Nbhhxo4JXEgJn++b1cb4hVrOLKyhSoZtvn2YOkO/EpWPoKRfRPAR+aaAgZ+IEslcHE 83Tt4p7t/SkXw== Message-ID: Date: Tue, 12 May 2026 11:02:22 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC v1 PATCH 0/11] Optimize this_cpu_*() ops for non-x86 (ARM64 for this series) To: Yang Shi , cl@gentwo.org, dennis@kernel.org, tj@kernel.org, urezki@gmail.com, catalin.marinas@arm.com, will@kernel.org, ryan.roberts@arm.com, akpm@linux-foundation.org, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260429170758.3018959-1-yang@os.amperecomputing.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit > ========= > The benchmarks are done on 160 core AmpereOne machine. The baseline is > v7.1-rc1 kernel. > > 1. Kernel Build > --------------- > Run kernel build (make -j160) with the default Fedora kernel config in a > memcg. > 13% - 18% sys time improvment > 3% - 7% wall time improvement This is pretty impressive! There was quite some feedback during the LSF/MM session, what's the current plan? Also, it was raised that Linus so far didn't enjoy per-process page tables. Is there a way forward? Finally, in the LSF/MM session, there was the question why the preemption handling is even required. Can you describe what the problem is? -- Cheers, David