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 C7B64C433F5 for ; Tue, 12 Oct 2021 17:05:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D83560EDF for ; Tue, 12 Oct 2021 17:05:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231672AbhJLRHD (ORCPT ); Tue, 12 Oct 2021 13:07:03 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:31520 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229606AbhJLRHB (ORCPT ); Tue, 12 Oct 2021 13:07:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634058299; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Zv2suu7TZ2BZjNAY7Fx5N+NNNZcHunY8SSActvahWDE=; b=V/h8sVsGe+ckFF2+JGsOwK6MEUwh+yHUdBggfI1zEoT+Zl54C3lMDlatzsOGzJozhSNjAz Jmp/46Zp9o2FzLegvLsNt+qy3w325DuoDHshIiPj/pNON6YZcY0wou+ENweX+HQ33mT+Oe PzWWdBQGO4ZFjFBmBI3Dssntp2Vufa0= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-185-DVP7h4UKMl-cdQklpPeyPw-1; Tue, 12 Oct 2021 13:04:58 -0400 X-MC-Unique: DVP7h4UKMl-cdQklpPeyPw-1 Received: by mail-ed1-f71.google.com with SMTP id c8-20020a50d648000000b003daa53c7518so485955edj.21 for ; Tue, 12 Oct 2021 10:04:58 -0700 (PDT) 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=Zv2suu7TZ2BZjNAY7Fx5N+NNNZcHunY8SSActvahWDE=; b=T+MvgEKmYWVEN0jtEmWSVi12j1TNeR+r2l3uXlyMxQokjJ4+yNIAaU2nxF3grNRjta Cp24laF8U68vCPN5+vllqWLqcabH0nQPhgTz4ZUhfbclfckAVYy1XsJ3EYPE62EE0gLj 1Db8/rtcL5R1BwSueK3fYIyRVSPgIrbbXRI5P2f74w41elTi5ATFRNPJ/hUaCGGeq2ZS B/Fx0bMEeevS+gVGBHAMzZYmQSaO6F885WFLaeGW0hO35h1gmHk/5UOCh45VRxUM+Bzy vjKymROYFG3ouocgIbg7jMEBBBp6l8/B2ei7z3+6HwYgX3y/mYVs/QnG1lghYQrrkkoU MlHQ== X-Gm-Message-State: AOAM533MbBkeLuSiRDGu8bP1pqA7kbUxAYOM776eKOkukWVE5TtxaAI+ AgwfFOxEbg37O1kw7BjcwdQnWrNR94p+8aZS0sArY7fGz2KcPAokHtBIPidORvidyOThe+DUwIr eJjkVnEM6SA2vhCwmqElfOy/M X-Received: by 2002:a17:907:7848:: with SMTP id lb8mr33622164ejc.494.1634058295745; Tue, 12 Oct 2021 10:04:55 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwHdjuAiKRrQdj3TGjYYQwVTXm0QdW86MwEWtHVztudehRLFxGkkxaVFB3lvRzbd7INiO0Xvg== X-Received: by 2002:a17:907:7848:: with SMTP id lb8mr33622143ejc.494.1634058295520; Tue, 12 Oct 2021 10:04:55 -0700 (PDT) Received: from krava ([83.240.63.48]) by smtp.gmail.com with ESMTPSA id e13sm5226755eje.95.2021.10.12.10.04.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 12 Oct 2021 10:04:54 -0700 (PDT) Date: Tue, 12 Oct 2021 19:04:53 +0200 From: Jiri Olsa To: Heiko Carstens Cc: Steven Rostedt , Thomas Gleixner , Ingo Molnar , Borislav Petkov , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/4] s390: DYNAMIC_FTRACE_WITH_DIRECT_CALL support Message-ID: References: <20211012133802.2460757-1-hca@linux.ibm.com> <20211012094852.7f6a59b8@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 12, 2021 at 04:59:02PM +0200, Heiko Carstens wrote: > On Tue, Oct 12, 2021 at 09:48:52AM -0400, Steven Rostedt wrote: > > On Tue, 12 Oct 2021 15:37:58 +0200 > > Heiko Carstens wrote: > > > This small series adds DYNAMIC_FTRACE_WITH_DIRECT_CALL support for > > > s390 and is based on linux-next 20211012. > ... > > > Besides the architecture backend this also adds s390 ftrace direct > > > call samples, and slightly changes config option handling a bit, so > > > that options only have to be selected. This way also additional future > > > architectures can easily add their trampolines to the samples. > ... > > > If ok, I'd like to get this upstream via the s390 tree with the next > > > merge window. > > > > A quick look at the patches look fine to me. I'll do a bit more digging > > before adding a Reviewed-by. > > > > One thing you may want to note, we are working on fixing direct trampolines > > that conflict with the function graph tracer, and have patches that fix it. > > I'm not that familiar on how ftrace works on s390, but you may want to > > investigate this, because if s390 has the issues that x86 has, where you > > can't have both function graph tracing and a direct trampoline on the same > > function. > > > > See here: > > > > https://lore.kernel.org/all/20211008091336.33616-1-jolsa@kernel.org/ > > I applied Jiri's patch set and the newly added selftest passes. nice, could I have your Tested-by? ;-) thanks, jirka > > Note: s390 will also get HAVE_DYNAMIC_FTRACE_WITH_ARGS support, which is > required for the new selftest - this is currently only in linux-next. > See commit 5740a7c71ab6 ("s390/ftrace: add HAVE_DYNAMIC_FTRACE_WITH_ARGS > support") in linux-next. > > Also manually testing with loading the ftrace-direct test module and > enabling the function graph tracer seems to work correctly: > > 6) + 15.138 us | } > 6) | wake_up_process() { > 6) | my_direct_func [ftrace_direct]() { > 6) | /* waking up ksoftirqd/6-44 */ > 6) 0.944 us | } > 6) | try_to_wake_up() { > 6) 0.185 us | kthread_is_per_cpu(); > > One thing to note: Jiri adds a new a sample module, which obviously > will not compile for s390. Not sure if the config mechanism I propose > with this patch set is the best way to address this - it would then > require to add a config option for each new sample module. >