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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 48C25C3A5A7 for ; Wed, 4 Sep 2019 15:41:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1CCF822CEA for ; Wed, 4 Sep 2019 15:41:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=joelfernandes.org header.i=@joelfernandes.org header.b="OFhv/wTf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731383AbfIDPlt (ORCPT ); Wed, 4 Sep 2019 11:41:49 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:44716 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730173AbfIDPls (ORCPT ); Wed, 4 Sep 2019 11:41:48 -0400 Received: by mail-pf1-f194.google.com with SMTP id q21so8456593pfn.11 for ; Wed, 04 Sep 2019 08:41:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=YkmhvjJ+pgtpfGA/ry21rjZ5udwkyVDS4daj2inyhQ8=; b=OFhv/wTfXpSTWbBxwvvpdfxytTFQfdfLwybiAAs8ZI3aeZcSZ14nGa9N0Ck/UxTDre nNoAjxYJb2pPTzKLzW5Ymq7uYV8Vw0raPkOvC8FwN9GTH4pkXQUhSIjORduKU0KSkOHk C9TuRPBE0HLxwuffjKlcqE00J3oNup4c59V44= 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:user-agent; bh=YkmhvjJ+pgtpfGA/ry21rjZ5udwkyVDS4daj2inyhQ8=; b=iU77W+6BmL4PzwfqOIvFsdHaegiBhygs1hKGPZxREynzi9nNV8deOjj2NHHFtreo7W ztceHQw2DkmDZz9WQT0RtpP2/j0x00QhS2wUfbtX7zLeO97+Tj91XCSspo/8MrHeRbhV 7xMDL0QaVbbA0fqfqDLC5Wyvc+ieN6n35613ipbhRfHITWkj87QZO6tF6wByyHUrv3Vx JmeGqCligT27jgeeGMchHLdNjx6h2lnQqWTUE9+IxHK3iY0Jr+VVbsK/EFc7V0YCxD5A DlVFdwWEhwzt7Xnv2PbDLChvPDHSpSUCFo6RlGzWbpSlkU0t4ncSOrvskRdT0e7evWtM +cDg== X-Gm-Message-State: APjAAAVHunsYThZ030KGFbAhUfz63ecc4VFJ8oFFWL8dAvZ8OU9FrIx4 hRf+/tkNmd4bHNwcDljDsq5VdA== X-Google-Smtp-Source: APXvYqxzKLSHeDd3GxD4h2HrBNmnJjwUJMWD1eNS6BbI6eH4aYU4FofiSiOeVMz3IHyDliJVu6XuWA== X-Received: by 2002:a65:5342:: with SMTP id w2mr35297459pgr.261.1567611708039; Wed, 04 Sep 2019 08:41:48 -0700 (PDT) Received: from localhost ([2620:15c:6:12:9c46:e0da:efbf:69cc]) by smtp.gmail.com with ESMTPSA id w6sm4952665pfw.84.2019.09.04.08.41.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Sep 2019 08:41:47 -0700 (PDT) Date: Wed, 4 Sep 2019 11:41:46 -0400 From: Joel Fernandes To: Alexei Starovoitov Cc: Peter Zijlstra , Valentin Schneider , Radim =?utf-8?B?S3LEjW3DocWZ?= , LKML , Ingo Molnar , Thomas Gleixner , Borislav Petkov , Dave Hansen , Steven Rostedt , "H. Peter Anvin" , Andy Lutomirski , Jirka =?iso-8859-1?Q?Hladk=FD?= , =?utf-8?B?SmnFmcOtIFZvesOhcg==?= , X86 ML , Qais Yousef Subject: Re: [PATCH 2/2] sched/debug: add sched_update_nr_running tracepoint Message-ID: <20190904154146.GK240514@google.com> References: <20190903154340.860299-1-rkrcmar@redhat.com> <20190903154340.860299-3-rkrcmar@redhat.com> <20190904042310.GA159235@google.com> <20190904081448.GZ2349@hirez.programming.kicks-ass.net> <20190904131154.GF144846@google.com> <20190904153330.GI240514@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 04, 2019 at 08:37:22AM -0700, Alexei Starovoitov wrote: > On Wed, Sep 4, 2019 at 8:33 AM Joel Fernandes wrote: > > > > On Wed, Sep 04, 2019 at 08:26:52AM -0700, Alexei Starovoitov wrote: > > > On Wed, Sep 4, 2019 at 6:14 AM Joel Fernandes wrote: > > > > > > > > True. However, for kprobes-based BPF program - it does check for kernel > > > > version to ensure that the BPF program is built against the right kernel > > > > version (in order to ensure the program is built against the right set of > > > > kernel headers). If it is not, then BPF refuses to load the program. > > > > > > This is not true anymore. Users found few ways to workaround that check > > > in practice. It became useless and it was deleted some time ago. > > > > Wow, Ok! Interesting! > > the other part of your email says about kernel header requirement. > This is not true any more as well :) > BTF relocations are already supported by the kernel, llvm, libbpf, > bpftool, pahole. > We'll be posting sample code soon. Ok, this landscape seems to be changing quite a bit. I was going by what I already know... Looking forward to catching up with the latest. Sorry, thanks, - Joel