From nobody Wed Dec 17 14:10:43 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65890C4167B for ; Mon, 27 Nov 2023 14:01:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233506AbjK0OBI (ORCPT ); Mon, 27 Nov 2023 09:01:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233569AbjK0N64 (ORCPT ); Mon, 27 Nov 2023 08:58:56 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E6A01988 for ; Mon, 27 Nov 2023 05:56:19 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EEEF8C433D9; Mon, 27 Nov 2023 13:56:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701093378; bh=AazvW4/a90V/YIaJshYrFG/FkUTxnxIHHqFsOEqmNJ4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ntekJ5o1Kg3FOTwvmE8wk2UcJ8STdTR6o0/0mRObGaDja1IUR/mN09HwhSyCHrQ7Y tKDmmGDJGr3zPJdSqeHibckLzET5C27oB5k+1YgcrC5+hE5J6/QcYdWcXJ/rv6+cO1 vysHWZ5eJ3w9reVI7N0wUSGA28Qmmy6WT/bnKGhqP3rXf2TPbUs/al9MBVY/ErwtzI thRFEEBt8L8GxozyFzO4kpX/M35wAnUyjZfElwVMGGBylfW/3B/bQ/B1WFvrdCZFQN M4hXsZWM3++MEYDBmzfDFSVdxLzWaVSRZ23A13EzcBvZiO1h8CbGpb+uMZAH9tMmXb wSu39Vjd0DFnQ== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v3 16/33] function_graph: Move graph notrace bit to shadow stack global var Date: Mon, 27 Nov 2023 22:56:11 +0900 Message-Id: <170109337141.343914.17947410912543913151.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <170109317214.343914.4784420430328654397.stgit@devnote2> References: <170109317214.343914.4784420430328654397.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt (VMware) The use of the task->trace_recursion for the logic used for the function graph no-trace was a bit of an abuse of that variable. Now that there exists global vars that are per stack for registered graph traces, use that instead. Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Masami Hiramatsu (Google) --- Changes in v2: - Make description lines shorter than 76 chars. --- include/linux/trace_recursion.h | 7 ------- kernel/trace/trace.h | 9 +++++++++ kernel/trace/trace_functions_graph.c | 10 ++++++---- 3 files changed, 15 insertions(+), 11 deletions(-) diff --git a/include/linux/trace_recursion.h b/include/linux/trace_recursio= n.h index 00e792bf148d..cc11b0e9d220 100644 --- a/include/linux/trace_recursion.h +++ b/include/linux/trace_recursion.h @@ -44,13 +44,6 @@ enum { */ TRACE_IRQ_BIT, =20 - /* - * To implement set_graph_notrace, if this bit is set, we ignore - * function graph tracing of called functions, until the return - * function is called to clear it. - */ - TRACE_GRAPH_NOTRACE_BIT, - /* Used to prevent recursion recording from recursing. */ TRACE_RECORD_RECURSION_BIT, }; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index cbe44998ef77..27b2b52c36cc 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -910,8 +910,17 @@ enum { =20 TRACE_GRAPH_DEPTH_START_BIT, TRACE_GRAPH_DEPTH_END_BIT, + + /* + * To implement set_graph_notrace, if this bit is set, we ignore + * function graph tracing of called functions, until the return + * function is called to clear it. + */ + TRACE_GRAPH_NOTRACE_BIT, }; =20 +#define TRACE_GRAPH_NOTRACE (1 << TRACE_GRAPH_NOTRACE_BIT) + static inline unsigned long ftrace_graph_depth(unsigned long *task_var) { return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3; diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_func= tions_graph.c index 66cce73e94f8..13d0387ac6a6 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -130,6 +130,7 @@ static inline int ftrace_graph_ignore_irqs(void) int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops) { + unsigned long *task_var =3D fgraph_get_task_var(gops); struct trace_array *tr =3D gops->private; struct trace_array_cpu *data; unsigned long flags; @@ -138,7 +139,7 @@ int trace_graph_entry(struct ftrace_graph_ent *trace, int ret; int cpu; =20 - if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) + if (*task_var & TRACE_GRAPH_NOTRACE) return 0; =20 /* @@ -149,7 +150,7 @@ int trace_graph_entry(struct ftrace_graph_ent *trace, * returning from the function. */ if (ftrace_graph_notrace_addr(trace->func)) { - trace_recursion_set(TRACE_GRAPH_NOTRACE_BIT); + *task_var |=3D TRACE_GRAPH_NOTRACE_BIT; /* * Need to return 1 to have the return called * that will clear the NOTRACE bit. @@ -240,6 +241,7 @@ void __trace_graph_return(struct trace_array *tr, void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops) { + unsigned long *task_var =3D fgraph_get_task_var(gops); struct trace_array *tr =3D gops->private; struct trace_array_cpu *data; unsigned long flags; @@ -249,8 +251,8 @@ void trace_graph_return(struct ftrace_graph_ret *trace, =20 ftrace_graph_addr_finish(gops, trace); =20 - if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) { - trace_recursion_clear(TRACE_GRAPH_NOTRACE_BIT); + if (*task_var & TRACE_GRAPH_NOTRACE) { + *task_var &=3D ~TRACE_GRAPH_NOTRACE; return; }