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b=XmrTNmWAF7+UGEO0+jM/dWHCTDewiOoYwE6o1rhI5tRqI7Rooar+ZAL5QK1X2pRJS j5gLDOpMV19Gd9oNijz+jgr4PzEaaIO+KsTvHtX6zh9Tj02kYoyhZAvJjNC0/dPqOU nt56lsPzrOFtu2jvy/etLQwO/wjfHZrrCRNZG0m2QeIszrI2F0JoMkjGE6i5LqbjAB UDM+N3/Rf5XLphUNElSB7FTiiH0fC+Ar6lVrBYieKSUJbuLfe3f67OPKs3YuRFcAdm DIiBtpfB16dwGdfsZoGM+UqpS4XzG23N5MH1jXZxwbgZNBi7waEZ4si3ckPYiOnMyR kwPn+cqE8oy8Q== Message-ID: Date: Tue, 7 Apr 2026 14:40:07 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] slub: clarify kmem_cache_refill_sheaf() comments Content-Language: en-US To: Hao Li , harry@kernel.org, akpm@linux-foundation.org Cc: cl@gentwo.org, rientjes@google.com, roman.gushchin@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260407120018.42692-1-hao.li@linux.dev> From: "Vlastimil Babka (SUSE)" In-Reply-To: <20260407120018.42692-1-hao.li@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 195FCA0013 X-Stat-Signature: m3fugs9shxo6zksctrj5n59y7ps536oo X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1775565611-85331 X-HE-Meta: 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 UV92swJz ELHDBsTetptE8ZYe+QGgOMfmKr2110oO2jOVt6gdl8lixjjNkjc0wYFLAWYkDo4VUK1OevlNcus7XTxjI3GdsSZ9/nZ5DQfUhQHcV3TJk9YKnOVf+dF1Uratb7lIDVdWtpU+fn0iC+AVXsvzuzef5jSz4aXrcWdnWYaONppn/AY4AciiRA+uTNFNlJ5hmk8Q4Y/gKUznbkfX5Tv5d16RTM6ktTon4M0bDqaGOG3j3eJDR8gKZDAKMzD4TD1lTLPCJSBHNDaeNwh6I2290FF0TRo/BseXPBT80AVmouENiiJns0tGKbVShDz8ZGUPrP5A+O/CG6XhJbJN7Vu0= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/7/26 13:59, Hao Li wrote: > In the in-place refill case, some objects may already have been added > before the function returns -ENOMEM. > Clarify this behavior and polish the rest of the comment for readability. > > Acked-by: Harry Yoo (Oracle) > Signed-off-by: Hao Li > --- > Thanks Harry for good suggestion! Thanks! Added to slab/for-next > --- > mm/slub.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/mm/slub.c b/mm/slub.c > index 4927407c9699..92362eeb13e5 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -5120,12 +5120,15 @@ void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp, > } > > /* > - * refill a sheaf previously returned by kmem_cache_prefill_sheaf to at least > - * the given size > + * Refill a sheaf previously returned by kmem_cache_prefill_sheaf to at least > + * the given size. > * > - * the sheaf might be replaced by a new one when requesting more than > - * s->sheaf_capacity objects if such replacement is necessary, but the refill > - * fails (returning -ENOMEM), the existing sheaf is left intact > + * Return: 0 on success. The sheaf will contain at least @size objects. > + * The sheaf might have been replaced with a new one if more than > + * sheaf->capacity objects are requested. > + * > + * Return: -ENOMEM on failure. Some objects might have been added to the sheaf > + * but the sheaf will not be replaced. > * > * In practice we always refill to full sheaf's capacity. > */