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=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B28D9C47254 for ; Tue, 5 May 2020 14:14:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 958302083B for ; Tue, 5 May 2020 14:14:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729561AbgEEOOU (ORCPT ); Tue, 5 May 2020 10:14:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1729266AbgEEOOO (ORCPT ); Tue, 5 May 2020 10:14:14 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CE6DC061A0F for ; Tue, 5 May 2020 07:14:14 -0700 (PDT) Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jVyKZ-0000mL-DX; Tue, 05 May 2020 16:13:55 +0200 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id D0D251001F5; Tue, 5 May 2020 16:13:54 +0200 (CEST) Message-Id: <20200505134101.340485295@linutronix.de> User-Agent: quilt/0.65 Date: Tue, 05 May 2020 15:16:35 +0200 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, "Paul E. McKenney" , Andy Lutomirski , Alexandre Chartre , Frederic Weisbecker , Paolo Bonzini , Sean Christopherson , Masami Hiramatsu , Petr Mladek , Steven Rostedt , Joel Fernandes , Boris Ostrovsky , Juergen Gross , Brian Gerst , Mathieu Desnoyers , Josh Poimboeuf , Will Deacon , "Peter Zijlstra (Intel)" Subject: [patch V4 part 1 33/36] x86,tracing: Robustify ftrace_nmi_enter() References: <20200505131602.633487962@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Peter Zijlstra ftrace_nmi_enter() trace_hwlat_callback() trace_clock_local() sched_clock() paravirt_sched_clock() native_sched_clock() All must not be traced or kprobed, it will be called from do_debug() before the kprobe handler. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Acked-by: Steven Rostedt (VMware) --- arch/x86/include/asm/paravirt.h | 2 +- arch/x86/kernel/tsc.c | 4 ++-- include/linux/ftrace_irq.h | 4 ++-- kernel/trace/trace_clock.c | 3 ++- kernel/trace/trace_hwlat.c | 2 +- 5 files changed, 8 insertions(+), 7 deletions(-) --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -17,7 +17,7 @@ #include #include -static inline unsigned long long paravirt_sched_clock(void) +static __always_inline unsigned long long paravirt_sched_clock(void) { return PVOP_CALL0(unsigned long long, time.sched_clock); } --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -207,7 +207,7 @@ static void __init cyc2ns_init_secondary /* * Scheduler clock - returns current time in nanosec units. */ -u64 native_sched_clock(void) +noinstr u64 native_sched_clock(void) { if (static_branch_likely(&__use_tsc)) { u64 tsc_now = rdtsc(); @@ -240,7 +240,7 @@ u64 native_sched_clock_from_tsc(u64 tsc) /* We need to define a real function for sched_clock, to override the weak default version */ #ifdef CONFIG_PARAVIRT -unsigned long long sched_clock(void) +noinstr unsigned long long sched_clock(void) { return paravirt_sched_clock(); } --- a/include/linux/ftrace_irq.h +++ b/include/linux/ftrace_irq.h @@ -7,7 +7,7 @@ extern bool trace_hwlat_callback_enabled extern void trace_hwlat_callback(bool enter); #endif -static inline void ftrace_nmi_enter(void) +static __always_inline void ftrace_nmi_enter(void) { #ifdef CONFIG_HWLAT_TRACER if (trace_hwlat_callback_enabled) @@ -15,7 +15,7 @@ static inline void ftrace_nmi_enter(void #endif } -static inline void ftrace_nmi_exit(void) +static __always_inline void ftrace_nmi_exit(void) { #ifdef CONFIG_HWLAT_TRACER if (trace_hwlat_callback_enabled) --- a/kernel/trace/trace_clock.c +++ b/kernel/trace/trace_clock.c @@ -22,6 +22,7 @@ #include #include #include +#include /* * trace_clock_local(): the simplest and least coherent tracing clock. @@ -29,7 +30,7 @@ * Useful for tracing that does not cross to other CPUs nor * does it go through idle events. */ -u64 notrace trace_clock_local(void) +u64 noinstr trace_clock_local(void) { u64 clock; --- a/kernel/trace/trace_hwlat.c +++ b/kernel/trace/trace_hwlat.c @@ -139,7 +139,7 @@ static void trace_hwlat_sample(struct hw #define init_time(a, b) (a = b) #define time_u64(a) a -void trace_hwlat_callback(bool enter) +noinstr void trace_hwlat_callback(bool enter) { if (smp_processor_id() != nmi_cpu) return;