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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 6DB7AC54E8B for ; Tue, 12 May 2020 12:19:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 52088206CC for ; Tue, 12 May 2020 12:19:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729959AbgELMTm (ORCPT ); Tue, 12 May 2020 08:19:42 -0400 Received: from mga06.intel.com ([134.134.136.31]:43213 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729879AbgELMTk (ORCPT ); Tue, 12 May 2020 08:19:40 -0400 IronPort-SDR: dHWVWfgUns/aGRR/OwiyjJFf3f3qjtcMLd+LGW/LI4w86kspBAZaS7PlwG8H5eWW6XNOAOV0z4 dQSKjuUd7zGg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 May 2020 05:19:40 -0700 IronPort-SDR: 8kJ/1g11Ha10ZzEkMxtOCtWr7YsFkm4MU7d7STfk3M+/Nb394wY4l1EnxrYDEYddfT3wWVJxbt ysUCYg0CDrmw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,383,1583222400"; d="scan'208";a="250879308" Received: from ahunter-desktop.fi.intel.com ([10.237.72.157]) by orsmga007.jf.intel.com with ESMTP; 12 May 2020 05:19:36 -0700 From: Adrian Hunter To: Arnaldo Carvalho de Melo Cc: Peter Zijlstra , Ingo Molnar , Masami Hiramatsu , Steven Rostedt , Borislav Petkov , "H . Peter Anvin" , x86@kernel.org, Mark Rutland , Alexander Shishkin , Mathieu Poirier , Leo Yan , Jiri Olsa , linux-kernel@vger.kernel.org Subject: [PATCH V7 08/15] ftrace: Add perf text poke events for ftrace trampolines Date: Tue, 12 May 2020 15:19:15 +0300 Message-Id: <20200512121922.8997-9-adrian.hunter@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200512121922.8997-1-adrian.hunter@intel.com> References: <20200512121922.8997-1-adrian.hunter@intel.com> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add perf text poke events for ftrace trampolines when created and when freed. There can be 3 text_poke events for ftrace trampolines: 1. NULL -> trampoline By ftrace_update_trampoline() when !ops->trampoline Trampoline created 2. [e.g. on x86] CALL rel32 -> CALL rel32 By arch_ftrace_update_trampoline() when ops->trampoline and ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP [e.g. on x86] via text_poke_bp() which generates text poke events Trampoline-called function target updated 3. trampoline -> NULL By ftrace_trampoline_free() when ops->trampoline and ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP Trampoline freed Signed-off-by: Adrian Hunter Acked-by: Peter Zijlstra (Intel) --- kernel/trace/ftrace.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 1103a8fcf142..abdf8f415a6e 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2802,6 +2802,13 @@ static void ftrace_trampoline_free(struct ftrace_ops *ops) { if (ops && (ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP) && ops->trampoline) { + /* + * Record the text poke event before the ksymbol unregister + * event. + */ + perf_event_text_poke((void *)ops->trampoline, + (void *)ops->trampoline, + ops->trampoline_size, NULL, 0); perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, ops->trampoline, ops->trampoline_size, true, FTRACE_TRAMPOLINE_SYM); @@ -6826,6 +6833,13 @@ static void ftrace_update_trampoline(struct ftrace_ops *ops) perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, ops->trampoline, ops->trampoline_size, false, FTRACE_TRAMPOLINE_SYM); + /* + * Record the perf text poke event after the ksymbol register + * event. + */ + perf_event_text_poke((void *)ops->trampoline, NULL, 0, + (void *)ops->trampoline, + ops->trampoline_size); } } -- 2.17.1