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b=lRGtm4ZGd7Di3ehxNoi+3eL7Fgoc1gHNi6kcJKeuVlAvImOajZ9Q6mr3gRJfZII3J xPNBMqf4XMsMHo7FLiqQU+FcA2fBytFdQuJu5fcvqLbhTQNWlSVjhT/pbJemPH96Q+ iTuB1Zg8Y1HI7FuWjR96a68daX9m/tRpvOHefmP6G4ciZtkAE12nFtxthoYlxJmVBK QSBXTu5wjwplFXHTUvLtgW75EmCgA6Sfp5xB4Drgl929hGe0/cdkVXV73WnF+jZTTS wuX7oC+htDdcGVYGrs+lVfKN8y5+QGZbWgjyoDvPQ7etcQuHUpYrp0ZGZ75Nakjs0I pgtPY/0vsDHKw== Message-ID: <49d7454b-b76b-43e7-a359-b2182545dbcc@kernel.org> Date: Wed, 29 Jul 2026 11:27:08 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 07/13] mm/slab: replace slab.stride with obj_exts_in_object Content-Language: en-US To: Harry Yoo Cc: Suren Baghdasaryan , Hao Li , Shakeel Butt , Alexander Potapenko , Marco Elver , Andrew Morton , Christoph Lameter , David Rientjes , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org References: <20260727-b4-objext_split-v3-0-c29ef0f1f257@kernel.org> <20260727-b4-objext_split-v3-7-c29ef0f1f257@kernel.org> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: D48164000A X-Rspamd-Server: rspam01 X-Stat-Signature: mgkc5bgpy64y5doycpk9u4tqte6jhtni X-HE-Tag: 1785317233-74719 X-HE-Meta: U2FsdGVkX18bJn4BtXKM5ORHyAJs3hlTE2//zqmBsU/QJXVz7Eijwt7EfoZ8ojK4801XyeZPP6jb+//ylAs8USbkvsP4Ymb7XvipNEAZAqM/13ETuJcsKo1mQYtRrlHJyKei4bKT4UB9x7PlizjI3bwJZecxPtXg8ZTlBUMar1YOapL/haUJTX/hF4P85QttyuQG1MchwAvhzyUfFLNiquTXvm3/0AuV15TGh5PN90ISLUrvV1BbPnUokUAQEYhkv9GCC7QR/0sZkH7AATkrGU/2akZq4kRk/G7sLrKH4ty/EGKNS2Lc7Y+Tv+g4wUf1z/TnxrTDYNIozeV/adD18q7XLvVcOfP2drSYGZs9j0xMb7+jMy/uv/tcPhVtoXtVtQWWcAhlmThRZ9P5F3GyWZFalCZxBF1anbeeI1sFeQ6SC8MdgOWIE3MJMl7azWuL4ND/avvMOJkNLaFDoSRd0e3e9Y/vAhJXCnioDadJH0fpoRBC9ZkTI8pvQg1/SQU65LKjaw8SQYjtClSSzOA+Sq7W1Uy17DXv89rLsJbbQ7D9Pfic5aHQ15AyZwQAOSEJYaGrt/HzO2JWFs2lGaQ8IG5l+BeAaaSik6jh5jH95J/NLqJ5q3eVfXFL9tlErfX8KlxQJRrXE8LVZphgBScwZjagsWoa8RCH6ksTVN4z5FDjfnOgrwLa5TZ0EcZmkxv/6fMipDfwlk65EagdB4TpVCcSedxzRSSAsr1+iLoQuZ4nBk2JH/lh2Ipuh3scwyswCPWs52FRruTECqu3HnQPyslY6eMwD7THvO+7oCMXE0n4KETEP6fWb48kr9rONBf9AQbPHTGsc4YmBA1zZ+cvJAGHNMyA6XmvguuXgXi6K1TMMuGwk3C0/iClJxzwGP0wXwYVNCyfBjYJi01WUADNSzWG4NM6kALcP/lVjagV+d19W29vfpjH5TRLF1sLDeveegOCHae9+G36QmqHNgM nthYPKce 9mz8V775xisAT1Xjl2DQ83rabCEw3g4bQio1gOkKlrDV5HbZWCqw3fE0Yi17GbDA6PyRusLzm0GaRmIl3Xpw9hdd44gwSSfEaLgxfAPLBCMWRKziZxBBXV/v7CoRdqFtOZBXSSH9P20UGmffDc3cQRauoSDT5iCeJSPd5o7GxF0SD2Y+c1HCDS7u4O6Q60cgobaVqLAIk+I8GsqYtBJ+h6+uSgukHM9y7ZU5858B0izeKl8yQYEAdND19Q4iEQ1W4Pi1UPgl4tKVgA8nWhltO+rEsuKVQnsiMN9JTQ+nrD6xbyYXIEHNPCWIftJzan8a5VT6Ux8nC9aIjLeFDfPLjFx3h2TRUx9CHm5cb Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 7/29/26 08:40, Harry Yoo wrote: > On Mon, Jul 27, 2026 at 02:54:01PM +0200, Vlastimil Babka (SUSE) wrote: >> The stride field is used to convert object index to an slabobj_ext so >> both compact arrays (kmalloc() or in-slab-leftover) and spread >> in-object-padding obj_ext layouts are supported. >> >> In practice thus the stride is always sizeof(slabobj_ext) or s->size. >> >> This simplifies the calculations, but with the upcoming slabobj_ext >> handling changes, it will be easier to stop storing the stride and >> instead just have a flag whether obj_ext is in the object padding. >> obj_exts_in_object() can then rely on this flag and slab_obj_ext() >> can use that to determine the stride. >> >> No functional change intended. Performance impact TBD, hopefully >> in the noise. > > Performance impact is not TBD anymore? Ah right, thanks. Since I didn't measure this commit separately, will remove the note completely and leave it to cover letter -> merge commit only. >> Reviewed-by: Suren Baghdasaryan >> Reviewed-by: Hao Li >> Signed-off-by: Vlastimil Babka (SUSE) >> --- > > Looks good to me, > Reviewed-by: Harry Yoo (Oracle) Thanks!