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t=1785910297; bh=o06/6FPH7j0zA4EIe85PZVZwlMghUXEo1x/4oJlkPUw=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=LkwWgCSqVEHenrGLY5DwHpwv7bCvEcjU1bM/SAkxZR2C7FbjCYG3GZB5To0YtXKhJ BROZukET64rl4TaA+ifSfCscJVUF45Sj1Mbg8SEyLyuM5osT/W4PTtOdU+dpW/5eRG lT1en6InMlUBFn/zGgyPhjerWsf2AfB8VVnhSXw4voTEHz6UfS0qFAT9XSyOwjJ8fM f54q8nYfmXaOeDNfFsURdyQ4grrm1xxLOlAzlipOCf89+cNJXPeLxgPi2gG5ZvQVWv qF4AxGW4BsKoX4/f0sTLmGSj0EsjUXEQ/4Y3hV+0ZhQ0+P1Cw/fzmiNjZE2Z54f5q5 k+NL4/dHq1Unw== Message-ID: <17add1ab-4390-4e8c-95ce-b8f0723d4c79@kernel.org> Date: Wed, 5 Aug 2026 08:11:29 +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)" Cc: Yang Shi , "Lorenzo Stoakes (ARM)" , Linus Torvalds , Mark Rutland , 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: <20260715180455.515692-1-yang@os.amperecomputing.com> <0344c559-1959-4531-9265-d5a5180eb7cd@arm.com> <25d1e09b-53e4-7cd5-87db-b58437e4e690@gentwo.org> <4887267b-dc26-4c33-96ca-8dff054a0d1f@kernel.org> <69f4cd9c-bd6c-4e5d-b8d1-a7be8408a57a@os.amperecomputing.com> <94c7988a-3ecf-4b26-b0a8-011bdc76283b@kernel.org> <29edec61-8f11-b9b1-3df9-2a51815ee771@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: 6EE3C180003 X-Stat-Signature: ewjtjdfwu1maejoyhemn5s7zqybd6ji9 X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1785910298-643705 X-HE-Meta: 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 B5J8pg9c Fi3lQgnpL3b1If4XHzATGHLlCJUOlMvIWZ3ZZFJ+x/9pgMhu6X/AcZb49Uh9cu1RV5sJvtrQhMxnBximlgx70Memm0FfQ67fBwpP10wJu8owhMiSA0ADcpJVhZM8Vg0HN4fMKlacJLriOlyMqRK5VOiwp5RQOREjRkhZTHn5Kc/kdTeHVjM1z4uI5zm+wSVTpHvq3gsKLj6KAcDMNFHYmkV2iotYx+VmqRST44YYJtJJbwBjpb0wePzJ0wqv/5pKB6V+y1h5qqiaWpO0jM0k7LAYA9YO0MhPMU4OQhusVCKGjyvfTW7GCqhjsxA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 8/5/26 00:35, Christoph Lameter (Ampere) wrote: > >> That's really all we are asking for. If there is a measurable performance >> difference, great. Share the results or point us at them if we missed them. > > Scanning over the patchset: It seems that you are using a special > instruction that is unfamiliar to me. Which processors support that? That's best asked in reply to Mark's patch set I think. -- Cheers, David