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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA91FC433EF for ; Wed, 29 Sep 2021 03:17:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A1A6E613D3 for ; Wed, 29 Sep 2021 03:17:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243947AbhI2DTA (ORCPT ); Tue, 28 Sep 2021 23:19:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243954AbhI2DS6 (ORCPT ); Tue, 28 Sep 2021 23:18:58 -0400 Received: from mail-pl1-x62c.google.com (mail-pl1-x62c.google.com [IPv6:2607:f8b0:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49DA7C061745 for ; Tue, 28 Sep 2021 20:17:18 -0700 (PDT) Received: by mail-pl1-x62c.google.com with SMTP id j14so550484plx.4 for ; Tue, 28 Sep 2021 20:17:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=hwK9T6fsSfOAiPPGKTKaR0RbJaAeTYNzmjOlW7jitEY=; b=nFIdHLGCLVCRPjTWGrKXIzVcs1vPMTKnkzRudQ6LRvtB/KcN3Kd3HRaUuTy08SLuz3 RfuThN1rubhjbTqq9WHaa9Dtn/DmJjC/SG+ok4YqcfUJ5l6H+Gt5chGqvXmJoNMDLCCu YXn6BPMq/yhKMJIWNdAhamSrmQQMxvb06htrK2vgEqeh8zqDVH6zpZWLhEoqMZ4bO16p c5GYS0QzAZYMKD3qcHspB6sV/fXbjVKtrZ/4M+Xg14eMWhxk/8YoWN9TDwKNuOBgkVpX 1CaC1TiqTztBL/dCPtRouTbLRJsohqoKu2mTjXmOptRWaOkkeK58YQVJl/KvL/bnS7uP 3u7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=hwK9T6fsSfOAiPPGKTKaR0RbJaAeTYNzmjOlW7jitEY=; b=3cv+mgiETApIRTqfzu4kJwHzTMhMKx1tMvOqNcyjy7RvB6IEvBQo7P+bogvtkE3s31 g0zqJGoAaflx1uZytvYY7mxDzX9PJKxjScgqQENBl3purEYgq8x/Pmxv+2iQDM3+wlnD 4Ys1LVSyUMBJxi+18axbl8lr9xzwyfxXbv5n4uu6YPhR5NCc5DCv25LCdbBUcUvqo8EY 5IYShiW7xQX5fvCbf2UPrmWotofT8kz5ig1NaLD4evUFtz9n7jQtrNqDytd7r6DkZwKb 5c10BExA8TT6kjfNY0aX6ESjcAo9SK41OWVrObzitJXvQrlYa3VWky+ipGXAVnGMgCSB 5K9A== X-Gm-Message-State: AOAM5339GDAul2dcF4fhLdUyfRyxfKfnPLyyj2xplMM144nuR2rP0zN3 /f1kYVgQP+Q/5tCpk8FVdLg= X-Google-Smtp-Source: ABdhPJziNJWcx5papsOv3tcpe7IcnAuypMQ1UzKuy1HgPdL8YbzRCFutow54i7+01mW3xVEcR1Y+gA== X-Received: by 2002:a17:90a:5295:: with SMTP id w21mr3778668pjh.31.1632885437808; Tue, 28 Sep 2021 20:17:17 -0700 (PDT) Received: from ast-mbp.dhcp.thefacebook.com ([2620:10d:c090:400::5:bbe4]) by smtp.gmail.com with ESMTPSA id c206sm469321pfc.220.2021.09.28.20.17.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Sep 2021 20:17:17 -0700 (PDT) Date: Tue, 28 Sep 2021 20:17:15 -0700 From: Alexei Starovoitov To: Andrii Nakryiko Cc: Joanne Koong , Martin KaFai Lau , bpf , Kernel Team Subject: Re: [PATCH v3 bpf-next 1/5] bpf: Add bloom filter map implementation Message-ID: <20210929031715.wvicuaf6iixm7xsb@ast-mbp.dhcp.thefacebook.com> References: <7957a053-8b98-1e09-26c8-882df6920e6e@fb.com> <118c7f22-f710-581f-b87e-ee07aced429a@fb.com> <20210927164110.gg33uypguty45huk@ast-mbp.dhcp.thefacebook.com> <20210927235144.7xp3ngebl67egc6a@ast-mbp.dhcp.thefacebook.com> <20210928162125.qsidw3zkzsfy4ms2@ast-mbp.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Tue, Sep 28, 2021 at 05:14:55PM -0700, Andrii Nakryiko wrote: > > So for Bloom filter you get performance advantage from a dedicated map > (due to having just 1 helper call to do N hashing operations). For > pure bitset, there seems to be little benefit at all because it is > basically ARRAY. I brought up bitset only as an idea to make bloomfilter map a bit more generic and was looking for feedback whether to call the new map "bitset that allows bloomfilter operations" or call it "bloomfilter that simplifies to bitset" with nr_hashes=0. It sounds that using bloomfilter as a base name fits better. > I haven't found SPDX header or any mention of GPL in > include/linux/jhash.h, so I assumed someone can just copy paste the > code (given the references to public domain). Seems like that's not > the case? Just curious about implications, license-wise, if there is > no SPDX? Is it still considered GPL? I believe so. Every project that copy pasted jhash from the kernel add SPDX gpl-2 to its source.