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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 B81E9C2BA83 for ; Wed, 12 Feb 2020 12:51:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9151220714 for ; Wed, 12 Feb 2020 12:51:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728042AbgBLMvD (ORCPT ); Wed, 12 Feb 2020 07:51:03 -0500 Received: from mga06.intel.com ([134.134.136.31]:63674 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725887AbgBLMvC (ORCPT ); Wed, 12 Feb 2020 07:51:02 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Feb 2020 04:51:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,428,1574150400"; d="scan'208";a="237702464" Received: from ahunter-desktop.fi.intel.com ([10.237.72.167]) by orsmga006.jf.intel.com with ESMTP; 12 Feb 2020 04:50:58 -0800 From: Adrian Hunter To: Peter Zijlstra Cc: Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , x86@kernel.org, Mark Rutland , Alexander Shishkin , Mathieu Poirier , Leo Yan , Arnaldo Carvalho de Melo , Jiri Olsa , linux-kernel@vger.kernel.org Subject: [PATCH V2 04/13] kprobes: Add perf ksymbol events for kprobe insn pages Date: Wed, 12 Feb 2020 14:49:40 +0200 Message-Id: <20200212124949.3589-5-adrian.hunter@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200212124949.3589-1-adrian.hunter@intel.com> References: <20200212124949.3589-1-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 Symbols are needed for tools to describe instruction addresses. Pages allocated for kprobe's purposes need symbols to be created for them. Add such symbols to be visible via perf ksymbol events. Signed-off-by: Adrian Hunter --- include/uapi/linux/perf_event.h | 5 +++++ kernel/kprobes.c | 12 ++++++++++++ 2 files changed, 17 insertions(+) diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index bae9e9d2d897..9b38ac04c110 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -1031,6 +1031,11 @@ enum perf_event_type { enum perf_record_ksymbol_type { PERF_RECORD_KSYMBOL_TYPE_UNKNOWN = 0, PERF_RECORD_KSYMBOL_TYPE_BPF = 1, + /* + * Out of line code such as kprobe-replaced instructions or optimized + * kprobes. + */ + PERF_RECORD_KSYMBOL_TYPE_OOL = 2, PERF_RECORD_KSYMBOL_TYPE_MAX /* non-ABI */ }; diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 229d1b596690..f880eb2189c0 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include @@ -184,6 +185,10 @@ kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c) kip->cache = c; list_add_rcu(&kip->list, &c->pages); slot = kip->insns; + + /* Record the perf ksymbol register event after adding the page */ + perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, (u64)kip->insns, + PAGE_SIZE, false, c->sym); out: mutex_unlock(&c->mutex); return slot; @@ -202,6 +207,13 @@ static int collect_one_slot(struct kprobe_insn_page *kip, int idx) * next time somebody inserts a probe. */ if (!list_is_singular(&kip->list)) { + /* + * Record perf ksymbol unregister event before removing + * the page. + */ + perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, + (u64)kip->insns, PAGE_SIZE, true, + kip->cache->sym); list_del_rcu(&kip->list); synchronize_rcu(); kip->cache->free(kip->insns); -- 2.17.1