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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 06303C4332B for ; Mon, 23 Mar 2020 12:54:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CB71020719 for ; Mon, 23 Mar 2020 12:54:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="njY/MqV4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727582AbgCWMya (ORCPT ); Mon, 23 Mar 2020 08:54:30 -0400 Received: from mail-pj1-f66.google.com ([209.85.216.66]:53352 "EHLO mail-pj1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728068AbgCWMya (ORCPT ); Mon, 23 Mar 2020 08:54:30 -0400 Received: by mail-pj1-f66.google.com with SMTP id l36so6138834pjb.3 for ; Mon, 23 Mar 2020 05:54:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=/wNuyOudK4lnsqabJXpE8j5qJG/piwUesE+vilid6rI=; b=njY/MqV4kTIbyg/UW3k9hanDcjn4a1sKkgXw3Z9TiZeLZRi7EpRSCMUTt/2UtUJNiY mY8t9qVCXFfU/7wqpqyR1zyUZOIw+WMty7Qa5dzMnTjLYsfOswLKKz3P/wcqjD/cQcl+ ELn/VNJt4rxEueVnkTzGEfAwQAYeDsTycd656EhnA6VaJMDXwGM/Gd7Qr38orjkIXWX+ dUfZ7I82Mpl4u1yxuIGuTfHSAlq461xdXAJLYdEhwIcghuw/xtMgEKpjNHhopw43JHYC FoezGQlFYQcAp5oOqKnT1HK+emrj8AWCJIbIyAZT07p4YR7ld5TL9br+X64S+I3ypN8J 7/4g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=/wNuyOudK4lnsqabJXpE8j5qJG/piwUesE+vilid6rI=; b=ovuHOVF1riwt4B8mFw0SWa1kdMV6b1YOj3L0jhYJPzz479RPfn5U6LNOYOCtJIBxEZ SQ3A9RpeS0FXOEy9p1Wq1076p5hHdDkEKvwE9FXZvd7MZSMeJGZ4k2UdID6ssiFpg53k k6K/kNCi04eoXEBo5/Dc7lBbnyurtrcFEONgbgJr34PR3BlagaHdiLCSyld29WllLq5C e2QurMtdhTTqub1psnTXu0iVLIeWHplM+r6Q7uyu8uYGaG/4vSbP/RnZ9OKSPLWARY/z 1d3GfJAqMBSzweWSlCG8OiQErVGedSRmA3jthnJb0jXvruf0GN6vzxUGYqYqUvXzeTcy iyJg== X-Gm-Message-State: ANhLgQ3UY41Y69DJ3TYg++sK3l5dwCo2lxhLB2pWHZkNRnVPNFdrKD4W Qc2X/u/PU8GhduVE/4jENsuvSg9t6Wo= X-Google-Smtp-Source: ADFU+vtyaEdAbfYW787X1+LvLtviL/vrTe0ZfS2jeq75dNbyXGO9+9rlsTKGrftaFMQrLBCNWOV+Xw== X-Received: by 2002:a17:902:ea8a:: with SMTP id x10mr10596888plb.328.1584968068790; Mon, 23 Mar 2020 05:54:28 -0700 (PDT) Received: from [192.168.0.18] ([106.254.212.20]) by smtp.gmail.com with ESMTPSA id c207sm13230000pfb.47.2020.03.23.05.54.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 23 Mar 2020 05:54:27 -0700 (PDT) Subject: Re: How to recheck 'maxactive' ? To: Masami Hiramatsu Cc: linux-trace-users@vger.kernel.org, "David S. Miller" References: <4762764a-6df7-bc93-ed60-e336146dce1f@gmail.com> <20200323154741.0643126b3684c950bb37bf7e@kernel.org> From: Taeung Song Message-ID: <0dbeb5a0-2834-0f74-66cb-839d5cbf64f9@gmail.com> Date: Mon, 23 Mar 2020 21:54:24 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200323154741.0643126b3684c950bb37bf7e@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-trace-users-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-users@vger.kernel.org Hi Masami, Thank you for the reply! And your patch looks great. Thanks, Taeung On 3/23/20 3:47 PM, Masami Hiramatsu wrote: > Hi Taeung, > > On Sun, 22 Mar 2020 23:06:20 +0900 > Taeung Song wrote: > >> Hi, >> >> After setting 'maxactive' for kretprobe, >> how can I recheck the value of 'maxactive' ? >> For example, in order to distinguish the difference >> between two kretprobe events >> (kmem_cache_alloc_node and kmem_cache_alloc_node10) >> >> $ cd /sys/kernel/debug/tracing >> $ echo 'r:kmem_cache_alloc_node kmem_cache_alloc_node' >> kprobe_events >> $ echo 'r10:kmem_cache_alloc_node10 kmem_cache_alloc_node' >> >> kprobe_events >> >> $ cat kprobe_events >> r:kprobes/kmem_cache_alloc_node kmem_cache_alloc_node >> r:kprobes/kmem_cache_alloc_node10 kmem_cache_alloc_node > > Oops! good catch. That must be a bug, since the kprobe_events design policy > is to support following operation. > > $ cat kprobe_events > /etc/event_setting > (reboot) > $ cat /etc/event_setting > kprobe_events > > What about below patch? > > From 935ed56819f2bfb7ac977f5c63273c9a6e3dfb42 Mon Sep 17 00:00:00 2001 > From: Masami Hiramatsu > Date: Mon, 23 Mar 2020 10:57:48 +0900 > Subject: [PATCH] ftrace/kprobe: Show the maxactive number on kprobe_events > > Show maxactive parameter on kprobe_events. > This allows user to save the current configuration and > restore it without losing maxactive parameter. > > Signed-off-by: Masami Hiramatsu > --- > kernel/trace/trace_kprobe.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index 362cca52f5de..d0568af4a0ef 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -1078,6 +1078,8 @@ static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev) > int i; > > seq_putc(m, trace_kprobe_is_return(tk) ? 'r' : 'p'); > + if (trace_kprobe_is_return(tk) && tk->rp.maxactive) > + seq_printf(m, "%d", tk->rp.maxactive); > seq_printf(m, ":%s/%s", trace_probe_group_name(&tk->tp), > trace_probe_name(&tk->tp)); > >