From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7CE65CD343F for ; Thu, 21 May 2026 03:17:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:References:From: Subject:Cc:To:Message-Id:Date:Content-Type:Content-Transfer-Encoding: Mime-Version:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=WnZgEvyl5JzulXJ71OevVX7wYBcNSF1YrTlDeDtAzPQ=; b=HUa81+Wv+IENEVDSecFbOKAW7I hVWsz0ktqbG8RW8aa1/vFimbEMFXRlFCApbxDlfblp9DWf24zWK+eicH14HabbJ2DtnfScAV8UsbC lK+mVeh9kDUxPnfslzn60DEbObStR2S3cJBKj8xvVz2GhihQ4yn+OrAhSgt2IKURWDefG7PrqnyxE Y/ig0bTYVe9sLXCPzcKjhMEsemnFFzHLAN4dUsaEYmY2dWHwilLajIO5SAzNalVKrgeTcB23IeHJi H8Gu5ziNiuztsIAFdcfSl2HWtnA7iFoa9RvompT4yZJvn/Onk7D251X3awi10lxoV06QFU9L8TIXZ mYZdx1wg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wPtuX-00000006Wia-1VCX; Thu, 21 May 2026 03:17:25 +0000 Received: from mail-pj1-x102d.google.com ([2607:f8b0:4864:20::102d]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wPtuU-00000006WhO-0mRO for linux-arm-kernel@lists.infradead.org; Thu, 21 May 2026 03:17:23 +0000 Received: by mail-pj1-x102d.google.com with SMTP id 98e67ed59e1d1-36a3dd2e66eso285803a91.0 for ; Wed, 20 May 2026 20:17:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=etsalapatis-com.20251104.gappssmtp.com; s=20251104; t=1779333441; x=1779938241; darn=lists.infradead.org; h=in-reply-to:references:from:subject:cc:to:message-id:date :content-transfer-encoding:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=WnZgEvyl5JzulXJ71OevVX7wYBcNSF1YrTlDeDtAzPQ=; b=zxoH4uZHmLSeUSCcohYddMGDxKqzrFPkQFoWZS7tioeqprECtmPZlJC9vQ6zFcHZfc mQAuuJ5Kk8upTEWuBnave7vYp+8l3YhePvUTvF4YbOXsEXQXopL9BgyYwg7Wsa92RccD VxFbXYBpc4srTexTBzjtaztPyytzJUQOa7D7ZK02M5BWWR8qglzMYBMPgEYlwjMtAa6K XUyXZaSGRgEi5e0ondfbS+5UJELQutPSBCNpqUbEHy21lOljQw50ri6ENuVSqebn6jpH 4FWXOP+Ll1fTeBQgZ50Hr/lxJOC8kMEtpBpi0MF/l8dWgFQXdal/XrK98r0098JI1pHf v2+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779333441; x=1779938241; h=in-reply-to:references:from:subject:cc:to:message-id:date :content-transfer-encoding:mime-version:x-gm-gg:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=WnZgEvyl5JzulXJ71OevVX7wYBcNSF1YrTlDeDtAzPQ=; b=fe6OsMyu1K/ugbvxCMbdrV0Ve5JDXa4B4MzOyNvKT/xULoKWyb0qmpH8Lky1mfWH0L L+9ZtiWTVOBEX4RIe4TKHNZkybqLI3OScENnbrPK5gYKcyyhYU6pNj7anFUSYDctrkXC qw0u8tLbW7rTNuOAFa0FljWMc9+7AcTKL2/RykTJ+FhQhJVBEe6nxZaTvIQHLhj3ZSla P8eGWLd2txvO4H4RgyRUF1IOOh21bAhIrw5QBOYJzVRdOMIKOSksFnat8pHQ45T3iDFj 9rq/t3QzxeZBmleADW69qkntHVF1ry9sNVZIDpbp/mQC4dhJbuxestIY08udjk3nCVWM eicg== X-Forwarded-Encrypted: i=1; AFNElJ9e8tkSZZqoxeBr58hGMXxPxZO2qabobXZ/d6GiOpvKqY2v+rZpG4QU19Bv+33R8i2tIbg2ARh3g9VsBqJsEjpM@lists.infradead.org X-Gm-Message-State: AOJu0Yzw3C6ENheHumnZhOH2HwAJdBYFMcZqCHIO1vBYBYDlFGDHoEXZ 89rQqGWl+F079oWOjRS46H8rXX61Xz4uZbyI4fS0r1iikUdPJLUh/zGBeCnEcGtoxvo= X-Gm-Gg: Acq92OG5baTWY+IbV7nT3xOwHGg8Im58SSibNiBD5SwIUuTJnE2MDfuAEcymBmxZH9v ZpSryP3El57UaLKCSFhhU5oQKhF9kN2IxDswlFcRijeL9nw0jur0IH8pOWIAMFPisynjxsdHSMH i+Hnp9D6jj82qWHfDiG436WDFS5gyB9k5RgkduKBt9fU1cH+mRCj5mBB0HaR0EAMi4Agom2QziV +XVLiYO801fb6dntKJYM9Zr9MB6D2T70I4b1UG0RUBkcozSs5M8TfiqRhZ39YB6jG3dT5+olv1c 4AnaP4e7rAaazesZG7QvB5Jt3CmTV7GOyXPoacwUnO5jfp/SSaSO4vBi1P0c48AKbFn0Fob3sWB SUX0eHo6P2izxZtU61/paAqKFZe7mik0Lu7VkJydI0SjNje4gsWztEnQY7EJzcpHQUBC1JZK81q ta4JeegerfW2b/Vlgteqcvhl9N X-Received: by 2002:a17:90b:1fc3:b0:366:16d1:6a26 with SMTP id 98e67ed59e1d1-36a45139004mr1096386a91.5.1779333441193; Wed, 20 May 2026 20:17:21 -0700 (PDT) Received: from localhost ([2001:569:58a0:da00:a5c8:c4ce:f7c1:40c1]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-36a4560779csm222458a91.1.2026.05.20.20.17.20 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 20 May 2026 20:17:20 -0700 (PDT) Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Wed, 20 May 2026 23:17:20 -0400 Message-Id: To: "Tejun Heo" , "David Vernet" , "Andrea Righi" , "Changwoo Min" , "Alexei Starovoitov" , "Andrii Nakryiko" , "Daniel Borkmann" , "Martin KaFai Lau" , "Kumar Kartikeya Dwivedi" Cc: "Peter Zijlstra" , "Catalin Marinas" , "Will Deacon" , "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "Dave Hansen" , "Andrew Morton" , "David Hildenbrand" , "Mike Rapoport" , "Emil Tsalapatis" , , , , , , Subject: Re: [PATCH 3/8] bpf: Add sleepable variant of bpf_arena_alloc_pages for kernel callers From: "Emil Tsalapatis" X-Mailer: aerc 0.21.0-0-g5549850facc2 References: <20260520235052.4180316-1-tj@kernel.org> <20260520235052.4180316-4-tj@kernel.org> In-Reply-To: <20260520235052.4180316-4-tj@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260520_201722_229920_5F4B525D X-CRM114-Status: GOOD ( 18.68 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed May 20, 2026 at 7:50 PM EDT, Tejun Heo wrote: > The existing kernel-side export of bpf_arena_alloc_pages is _non_sleepabl= e > only - it's used by the verifier to inline the kfunc when the call site i= s > non-sleepable. There is no sleepable equivalent for kernel callers; the > kfunc bpf_arena_alloc_pages itself is BPF-only. > > sched_ext needs sleepable kernel-side allocs for its arena pool init/grow > paths. Add bpf_arena_alloc_pages_sleepable() mirroring the _non_sleepable > wrapper but passing sleepable=3Dtrue to arena_alloc_pages(). > > Signed-off-by: Tejun Heo Reviewed-by: Emil Tsalapatis > --- > include/linux/bpf.h | 8 ++++++++ > kernel/bpf/arena.c | 13 +++++++++++++ > 2 files changed, 21 insertions(+) > > diff --git a/include/linux/bpf.h b/include/linux/bpf.h > index 831996c411cf..64968ca6db51 100644 > --- a/include/linux/bpf.h > +++ b/include/linux/bpf.h > @@ -679,6 +679,8 @@ int bpf_dynptr_from_file_sleepable(struct file *file,= u32 flags, > void *bpf_arena_alloc_pages_non_sleepable(void *p__map, void *addr__ign,= u32 page_cnt, int node_id, > u64 flags); > void bpf_arena_free_pages_non_sleepable(void *p__map, void *ptr__ign, u3= 2 page_cnt); > +void *bpf_arena_alloc_pages_sleepable(void *p__map, void *addr__ign, u32= page_cnt, int node_id, > + u64 flags); > #else > static inline void *bpf_arena_alloc_pages_non_sleepable(void *p__map, vo= id *addr__ign, u32 page_cnt, > int node_id, u64 flags) > @@ -689,6 +691,12 @@ static inline void *bpf_arena_alloc_pages_non_sleepa= ble(void *p__map, void *addr > static inline void bpf_arena_free_pages_non_sleepable(void *p__map, void= *ptr__ign, u32 page_cnt) > { > } > + > +static inline void *bpf_arena_alloc_pages_sleepable(void *p__map, void *= addr__ign, u32 page_cnt, > + int node_id, u64 flags) > +{ > + return NULL; > +} > #endif > =20 > extern const struct bpf_map_ops bpf_map_offload_ops; > diff --git a/kernel/bpf/arena.c b/kernel/bpf/arena.c > index 1c0b87ecc817..a811cf6170fa 100644 > --- a/kernel/bpf/arena.c > +++ b/kernel/bpf/arena.c > @@ -934,6 +934,19 @@ void *bpf_arena_alloc_pages_non_sleepable(void *p__m= ap, void *addr__ign, u32 pag > =20 > return (void *)arena_alloc_pages(arena, (long)addr__ign, page_cnt, node= _id, false); > } > + > +void *bpf_arena_alloc_pages_sleepable(void *p__map, void *addr__ign, u32= page_cnt, > + int node_id, u64 flags) > +{ > + struct bpf_map *map =3D p__map; > + struct bpf_arena *arena =3D container_of(map, struct bpf_arena, map); > + > + if (map->map_type !=3D BPF_MAP_TYPE_ARENA || flags || !page_cnt) > + return NULL; > + > + return (void *)arena_alloc_pages(arena, (long)addr__ign, page_cnt, node= _id, true); > +} > + > __bpf_kfunc void bpf_arena_free_pages(void *p__map, void *ptr__ign, u32 = page_cnt) > { > struct bpf_map *map =3D p__map;