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Mozilla Thunderbird Subject: Re: [PATCH] btrfs: replace kcalloc() calls to kzalloc_objs() To: =?UTF-8?Q?Miquel_Sabat=C3=A9_Sol=C3=A0?= , Johannes Thumshirn Cc: "dsterba@suse.com" , "clm@fb.com" , Naohiro Aota , "linux-btrfs@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "kees@kernel.org" References: <20260223234451.277369-1-mssola@mssola.com> <076d767a-48f3-4c71-87d5-5c304513f9a8@wdc.com> <87wm0263lz.fsf@> Content-Language: en-US From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; keydata= xsBNBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAHNIlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT7CwJQEEwEIAD4CGwMFCwkI 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Namely: If you assume every btrfs developer is aware of all slab/mm/vfs/whatever= =20 subsystem development, then I'd say you're wrong. Thus you should mention the commit (which is not yet in our developmenet= =20 tree), and at least have a short reason on the benefit. >=20 >> Internal introspection of the allocated type now becomes possible, >> allowing for future alignment-aware choices to be made by the >> allocator and future hardening work that can be type sensitive. >=20 > Should I put this in the commit message as well, regardless of the > commit explaining this being quoted? >=20 > There's also the argument of dropping 'sizeof' to be more ergonomic. To > me, though, and considering how these helpers have been applied > tree-wide, I see this change more as aligning us with this recent > tree-wide move, which also affected btrfs (see commit 69050f8d6d07 > "treewide: Replace kmalloc with kmalloc_obj for non-scalar types").