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 EA616C433FE for ; Thu, 4 Nov 2021 10:59:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D863460200 for ; Thu, 4 Nov 2021 10:59:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231293AbhKDLCR (ORCPT ); Thu, 4 Nov 2021 07:02:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231171AbhKDLCQ (ORCPT ); Thu, 4 Nov 2021 07:02:16 -0400 Received: from mail-qk1-x72f.google.com (mail-qk1-x72f.google.com [IPv6:2607:f8b0:4864:20::72f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 437C7C061203 for ; Thu, 4 Nov 2021 03:59:38 -0700 (PDT) Received: by mail-qk1-x72f.google.com with SMTP id bp7so5180264qkb.10 for ; Thu, 04 Nov 2021 03:59:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mojatatu-com.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=yk5XgrdOGaW3p+sZvRRyB5VgAQCpuos1tmstcywTUC4=; b=XX1YBYYHmk1cGhVONndzHMCKWuohW4I4dM1TtuQ9FZOpOuKRiNQ7W8lU0mLOfMXMln tebH6GbKj86VppLGa3M9D3purC3zTa3kl4odzXyqfOMep4hmM3a0qwX/osMUd86fnJex U0DIvfNePhGdPEOvHNjDsXdK5/GWVJUwXUERwJiGXk/2e2mRrXAYzCD3Qpc+LQ/sb0Gb cThFB+zRxr3kmrwkLC58FnNMtAQW3aKy7QMCYwgjlB/2fidVHlkLUMDLdampm91nvXDi 09TcE3LMsn5DCPDnkN07mT+vT4KeTjY8hiKaOrekAU9PQlcPpsIzBdCZ4ckpq+SnY5DM w6JA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=yk5XgrdOGaW3p+sZvRRyB5VgAQCpuos1tmstcywTUC4=; b=kQFYaZfhTO7ilNTAWjQvY1qe8UruBS1CCVptlMyQnowz9co56pfIdNKET1VAFoFWAX lEhyoVsGgI5TnihgwAewAGhtI7EfAx0YyktAQaGrEpkTWdn+aFABdKwwr5IRJyDYfKwL XIEDZNz5WIENcj+p/RF2YEynGt+pjQiJPhMewN3wafIvJpBSza+gdlO8NCVc8czEhwdM vfOTuarUNMogKrNJCEZ/BSS1dJpa/BvHY4ytGnGhBeaYC276JLQLD3nkwbTLbgHOohZU WPgEpkb02hZThHs/uWzPslOq+ILj1800DPqnte8oT+d8ZL68bi8JKuwtP7ULpo+pkoNt sbrQ== X-Gm-Message-State: AOAM532tL4hvX0WZaRtcA8XmO/1UpVH4q/NxGoOh2T3VqjWiXis4p4K4 2RpN4A+o2MA2QtLAHOzIRqQNrQ== X-Google-Smtp-Source: ABdhPJzhUAIh65nsdBGdq1eovhwrx6kLDOIqjGAzGexR5wn7UKV0JMgWgt2ucF4Fw2LrUUBhtCqJSg== X-Received: by 2002:a05:620a:4086:: with SMTP id f6mr40328253qko.220.1636023577438; Thu, 04 Nov 2021 03:59:37 -0700 (PDT) Received: from [192.168.1.173] (bras-base-kntaon1617w-grc-33-142-112-185-132.dsl.bell.ca. [142.112.185.132]) by smtp.googlemail.com with ESMTPSA id v14sm101547qkp.9.2021.11.04.03.59.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 04 Nov 2021 03:59:36 -0700 (PDT) Message-ID: <4e602c87-9764-829c-4763-38f4ac057b7c@mojatatu.com> Date: Thu, 4 Nov 2021 06:59:35 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.2.1 Subject: Re: [RFC PATCH v3 0/3] Introduce BPF map tracing capability Content-Language: en-US To: Joe Burton Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, Petar Penkov , Stanislav Fomichev , Joe Burton References: <20211102021432.2807760-1-jevburton.kernel@gmail.com> From: Jamal Hadi Salim In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-11-03 13:12, Joe Burton wrote: > That's a good point. Since the probe is invoked before the update takes > place, it would not be possible to account for the possibility that the > update failed. > > Unless someone wants the `pre update' hook, I'll simply adjust the > existing hooks' semantics so that they are invoked after the update. > As discussed, this better suits the intended use case. > If the goal is to synchronize state between two maps (if i understood correctly the intent) then it is more useful to go post-update. cheers, jamal