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Date: Wed, 20 May 2026 13:47:32 -1000
Message-ID: <eaeb316b7a45956ed5f335050e6e9538@kernel.org>
From: Tejun Heo <tj@kernel.org>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Peter Zijlstra <peterz@infradead.org>
Cc: David Vernet <void@manifault.com>,
	Andrea Righi <arighi@nvidia.com>,
	Changwoo Min <changwoo@igalia.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Andrii Nakryiko <andrii@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Martin KaFai Lau <martin.lau@linux.dev>,
	Kumar Kartikeya Dwivedi <memxor@gmail.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Thomas Gleixner <tglx@kernel.org>,
	Ingo Molnar <mingo@redhat.com>,
	Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	David Hildenbrand <david@kernel.org>,
	Mike Rapoport <rppt@kernel.org>,
	Emil Tsalapatis <emil@etsalapatis.com>,
	sched-ext@lists.linux.dev,
	bpf@vger.kernel.org,
	x86@kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 7/8] sched_ext: Sub-allocator over kernel-claimed BPF arena pages
In-Reply-To: <DIM6W7GRZK2N.14AH43S1XTFCG@gmail.com>
References: <20260517211232.1670594-1-tj@kernel.org>
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Hello,

On Mon, May 18, 2026 at 04:26:11PM -0700, Alexei Starovoitov wrote:
> Well, this gen_pool based allocator of arena memory is a temporary hack.
> It's ok for rare allocation like in this at scx init time, but not suitable
> for active arena management. We don't need to expose it beyond scx.

I see. Peter, as Alexei is already prototyping a slab-based arena
allocator, how about keeping the gen_pool layer scx-local for now? Once
the proper allocator lands, scx can switch to it and the custom piece
goes away.

Thanks.

--
tejun