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b=FWmZBXqcB3Idi01HEF+CZf/fEEpvgebfW3IQU5I+fqVB4HQp3R3crRPVxd6JfW9KY EWWbYdFrbBWv/h6rv8zlKwwfM8yq/yejMkfknY0dOrzIuPHpXDBx7YSZE4sDMG3xum 1hWBMMWTopZ24hodB4HHFOoa32B54AVhKSd8jUMXI5tR7h4TRBSTYq38+qKSDUoDJm oLU42Fd3T8I8X81WMlz0NGHvHqImCed/IKBwnNOiK5VcPNTZRbGZCBcHrR8rZsvFgS vwtRT5pxsfRCV+v+1bJw7BRo+WHw4hOmOnLo1FSbgyj9S5PnmtGOfe5/HrEzSM+ybp Pp1W+rF9kGXRw== Message-ID: <4baf6edb-c84b-4da9-b905-4d40d4bf5fdc@kernel.org> Date: Tue, 4 Aug 2026 23:48:19 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC v2 PATCH 0/16] Optimize this_cpu_*() ops for non-x86 (ARM64 for this series) To: "Christoph Lameter (Ampere)" , "Lorenzo Stoakes (ARM)" Cc: Linus Torvalds , Mark Rutland , Yang Shi , Ryan Roberts , dennis@kernel.org, tj@kernel.org, urezki@gmail.com, catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Jason Gunthorpe References: <0344c559-1959-4531-9265-d5a5180eb7cd@arm.com> <25d1e09b-53e4-7cd5-87db-b58437e4e690@gentwo.org> <4887267b-dc26-4c33-96ca-8dff054a0d1f@kernel.org> <8d6119c7-2216-fcdd-d0b9-cc60ccc8caf3@gentwo.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: E9DC48000E X-Rspamd-Server: rspam10 X-Rspam-User: X-Stat-Signature: u46kaqkcj3ptjg6zsonmb495wzwc7p5b X-HE-Tag: 1785880107-604950 X-HE-Meta: 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 p50stQH6 JG9mgdxzKNQO+goQfsY0eHIAkRSAVp7CCGCJ8lgkiq1k1E9tWVf7HJNlm/GsjtdndQSZRrqetUcJ7DhwWIjYJtx2TK95L3w3iMdudHix69+XECNaAmCVexDMzIXKFuH8fz/BU0d81WJFI0HU849LtWmkMrz0eLrNalxtzO5bbRCKuOW9EVZIuKBq6vP1AKPiOJwoo33GTwk7wyaqd4lgpL+LDtApFlUydPyBPCEkR+Zf1c2ih90Vueq7JufJecx4FT4HjeNXBizdJKDMOMLeJs805svMbTX8lpaiM+gf+l3UPEM62DjJH0S+Dow== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > These are operations that are key to the performance in critical parts of > memory management and this code is replicated by being inlined thousands > of times in the kernel. Cool, then it is easy to show the difference by running micro + macro benchmarks. -- Cheers, David