From patchwork Thu Feb 27 18:58:07 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13995034 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9577D1F5841; Thu, 27 Feb 2025 18:57:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740682659; cv=none; b=Rf23leZf15lDPe2to35/sPKD5XskSLPZdWf1khVnIG3MQ0LlBtfs2CygzSzFcHXfPmBycHrqQliM6L/mkAGlF/mONLZnoZWNgKSeL0Y7qepiJTeLx1bp/KzoK4zVe0foUeKRJB6gAkO1FJIHCeh3d0uJCVVfZs0Xf4SKEPwWIOM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740682659; c=relaxed/simple; bh=o0vu4EXSlywMKNgJRw80ZeDrMF/DIUZY7Gu0mhkAXg0=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=c6CbcHVWZ0JPDYYc8UV6YNPo55rljHFkvkneVF6I1pLSoJvCZDOBpsHvCytXJi3Ea1yE1q3xjDi1/JpjVgzupOGZmudD8qoRAKXgGdAFHdZcJG55yck2A28TXpZhz1PK5vszAolIWBgMQCxtmLdliPx6R/UAZox4F5avagNGRr8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5222DC4CEEF; Thu, 27 Feb 2025 18:57:39 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98) (envelope-from ) id 1tnj5T-00000009nS3-0Yay; Thu, 27 Feb 2025 13:58:23 -0500 Message-ID: <20250227185822.978998710@goodmis.org> User-Agent: quilt/0.68 Date: Thu, 27 Feb 2025 13:58:07 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Sven Schnelle , Paul Walmsley , Palmer Dabbelt , Albert Ou , Guo Ren , Donglin Peng , Zheng Yejian Subject: [PATCH v4 3/4] ftrace: Have funcgraph-args take affect during tracing References: <20250227185804.639525399@goodmis.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Steven Rostedt Currently, when function_graph is started, it looks at the option funcgraph-args, and if it is set, it will enable tracing of the arguments. But if tracing is already running, and the user enables funcgraph-args, it will have no effect. Instead, it should enable argument tracing when it is enabled, even if it means disabling the function graph tracing for a short time in order to do the transition. Acked-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_functions_graph.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 5049fe25ceef..71b2fb068b6b 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -464,7 +464,7 @@ static int graph_trace_init(struct trace_array *tr) else tr->gops->retfunc = trace_graph_return; - /* Make gops functions are visible before we start tracing */ + /* Make gops functions visible before we start tracing */ smp_mb(); ret = register_ftrace_graph(tr->gops); @@ -475,6 +475,28 @@ static int graph_trace_init(struct trace_array *tr) return 0; } +static int ftrace_graph_trace_args(struct trace_array *tr, int set) +{ + trace_func_graph_ent_t entry; + + if (set) + entry = trace_graph_entry_args; + else + entry = trace_graph_entry; + + /* See if there's any changes */ + if (tr->gops->entryfunc == entry) + return 0; + + unregister_ftrace_graph(tr->gops); + + tr->gops->entryfunc = entry; + + /* Make gops functions visible before we start tracing */ + smp_mb(); + return register_ftrace_graph(tr->gops); +} + static void graph_trace_reset(struct trace_array *tr) { tracing_stop_cmdline_record(); @@ -1607,6 +1629,9 @@ func_graph_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) if (bit == TRACE_GRAPH_GRAPH_TIME) ftrace_graph_graph_time_control(set); + if (bit == TRACE_GRAPH_ARGS) + return ftrace_graph_trace_args(tr, set); + return 0; }