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Howlett" , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Uladzislau Rezki , Sidhartha Kumar , linux-mm@kvack.org, linux-kernel@vger.kernel.org, rcu@vger.kernel.org, maple-tree@lists.infradead.org, Alexei Starovoitov , Sebastian Andrzej Siewior , Venkat Rao Bagalkote , Qianfeng Rong , Wei Yang , "Matthew Wilcox (Oracle)" , Andrew Morton , Lorenzo Stoakes , WangYuli , Jann Horn , Pedro Falcato Subject: Re: [PATCH v8 00/23] SLUB percpu sheaves Message-ID: References: <20250910-slub-percpu-caches-v8-0-ca3099d8352c@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Queue-Id: 0B07FC0004 X-Rspamd-Server: rspam03 X-Stat-Signature: dnc843j5xy3m9eoin4n8ppe94b69ojk3 X-HE-Tag: 1759903479-38005 X-HE-Meta: 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 HJWN2jG4 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Oct 07, 2025 at 10:03:04AM +0200, Vlastimil Babka wrote: > Basically it's for situations where you have an upper bound on the objects > you might need to allocate in some restricted context where you can't fail > but also can't reclaim etc. The steps are: Ok, so you still need a step where you reserve, which can fail and only after that guarantee you can allocate up to the reservation? I.e. not a replacement for mempools? Just asking because I recently had to implement a mempool_alloc_batch to allow grabbing multiple objects out of a mempool safely for something I'm working on.