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 X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC81FC433E0 for ; Tue, 30 Jun 2020 03:03:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 89D1320674 for ; Tue, 30 Jun 2020 03:03:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tY+fcD2j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728049AbgF3DDk (ORCPT ); Mon, 29 Jun 2020 23:03:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727981AbgF3DDj (ORCPT ); Mon, 29 Jun 2020 23:03:39 -0400 Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C43D4C061755; Mon, 29 Jun 2020 20:03:39 -0700 (PDT) Received: by mail-pj1-x1041.google.com with SMTP id u8so8572974pje.4; Mon, 29 Jun 2020 20:03:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=XA8dmfsnowB29muMEII+hjtwxRd8bumA8pK3ztGMTyA=; b=tY+fcD2j7o4g96NpIW0tc4gP01vbJIG0CyWS9YwOWBDnKGjn7+dav4O3f1raKTjdi9 UYlR0T2CYRODVQFxg+sY62amWsFsx43UHOlz7FJ8QfPKPUYmfMWA/BnHm2WKHjH7BruH gXbjfr4SMrIhhMULlU4YU9+ok+1pW7GgYloZD8Xso5IUfzJwcjjTEffXv0pUiaVC3KjP dOvoWvC9HEEsVfmy7MhdNMbM9FTbDcDnnDux569jkfK50DOk+vFHFaZLibp3NVlLSWua j2l4LZQFDRMvjasJWoalj6EMAGGrtl52uALPC8uKtj4VUiNeiQYP2YcjI32ytNsQly3J 1GMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=XA8dmfsnowB29muMEII+hjtwxRd8bumA8pK3ztGMTyA=; b=JpJV2zQQv6nUc/0DobNtAoeOgN1VmUr2yHjlY88FTgoYXjke7R9ISC8g2oEEg8dSMu Uhe3Hli2YKoGp8XhJjh3YhPnCdgLjQg3WyNhb3hE9y9DZFc9c0+MYXoUZdqg5bll8Lqc P0VLlU6g44h7UWDNGgk4lhwe4taug1RYWSHSsbI1Fo9/MRefyxn/VsPundGjVgyLjf5V Y40C3cqiZ9wc/S8Si3wsYXxQ1JhlG3DvVxAD8CmyaM3VWzeHuOyWKmXAV/vPcNcXsTjf yyHvAazi8hjxCiAuP2VMgw+LO7B29Qzxa+CmQUZfQ7s4qkuLFLVwBl79xN4AyS6sA1FN lEjQ== X-Gm-Message-State: AOAM532tlxLBssk/HFD35tnV0LIX2SRvXLqSTXYclqVOyVDheWlsic3U NLSv2cOzYLyYolbxQ1JimAl+0O9a X-Google-Smtp-Source: ABdhPJz3K8311SFY50MRIAfdwi9kDcElrSoVx/1Tyg/+XENmFMHHMHHj3F1tvxCHU+TSs9/+fVW9+A== X-Received: by 2002:a17:902:c411:: with SMTP id k17mr14915199plk.165.1593486219226; Mon, 29 Jun 2020 20:03:39 -0700 (PDT) Received: from ast-mbp.dhcp.thefacebook.com ([2620:10d:c090:400::5:140c]) by smtp.gmail.com with ESMTPSA id x24sm911049pfo.12.2020.06.29.20.03.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 29 Jun 2020 20:03:38 -0700 (PDT) Date: Mon, 29 Jun 2020 20:03:36 -0700 From: Alexei Starovoitov To: Andrii Nakryiko Cc: "David S. Miller" , Daniel Borkmann , "Paul E . McKenney" , Networking , bpf , Kernel Team Subject: Re: [PATCH v4 bpf-next 2/5] bpf: Introduce sleepable BPF programs Message-ID: <20200630030336.whvjlwtppcl3aj3u@ast-mbp.dhcp.thefacebook.com> References: <20200630003441.42616-1-alexei.starovoitov@gmail.com> <20200630003441.42616-3-alexei.starovoitov@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Mon, Jun 29, 2020 at 06:15:41PM -0700, Andrii Nakryiko wrote: > > > > +/* when rcu_read_lock_trace is held it means that some sleepable bpf program is > > + * running. Those programs can use bpf arrays and preallocated hash maps. These > > + * map types are waiting on programs to complete via > > + * synchronize_rcu_tasks_trace(); > > Wanted to leave comment that "map types are waiting" is outdated after > patch #1 and then recalled map-in-map complexities. So depending if > I'm right or wrong regarding issue in patch #1, this would stay or has > to be removed. Good catch. The comment is outdated. map-in-map is not supported with sleepable yet simply because I didn't have time to think it through. > > + verbose(env, > > + "Sleepable programs can only use array and hash maps\n"); > > nit: message is a bit misleading. per-cpu array is also an array, yet > is not supported. yes. It's generic to avoid updating it too often. map-in-map is also not supported yet, but it's a hash and array too.