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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 96DCDCA9EC9 for ; Tue, 5 Nov 2019 00:17:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 69C8821882 for ; Tue, 5 Nov 2019 00:17:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572913045; bh=aa+lHiitl6Vs5l8bpw2fpH46b6u0fQ7ZvdPGLvO8nsQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=voELlHRFpln19HOYpYHaGde6jhPfdfOOSitX1JBlG1MZ0Bfej52NlEGL/EFfmJUao 3fXZuGgKsNeXTXrjegbB3vvtVkGdKYtIk9Emr/WpUQheUHXoxsDXD6Rzvbpt544qUK X9xDxzcgp2zaTlVlCDQGjqUd8syr41glRB3ywYFU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387610AbfKEARY (ORCPT ); Mon, 4 Nov 2019 19:17:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:41572 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387415AbfKEARY (ORCPT ); Mon, 4 Nov 2019 19:17:24 -0500 Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 37F7F214D9; Tue, 5 Nov 2019 00:17:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572913043; bh=aa+lHiitl6Vs5l8bpw2fpH46b6u0fQ7ZvdPGLvO8nsQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g7rosmHXDLrkipKWqVA+7ktVMUR+H/QMwCtVNJh6llhpPHC6YbzhP9RYJO4b3eBcz Dx5WbjSaWCw705CkVGg//+a0uSz70BbnuR2j9TIsLhYnJ9i3M8gYCkWdd1CUIipSqU 6szg8p4C3j9L0gtLyJ2W/iHPM7JNaRm2dp/DjGjc= From: Masami Hiramatsu To: Arnaldo Carvalho de Melo Cc: Masami Hiramatsu , Ingo Molnar , Steven Rostedt , linux-kernel@vger.kernel.org, Tom Zanussi , Ravi Bangoria , Namhyung Kim Subject: [PATCH 4/5] perf probe: Support DW_AT_const_value constant value Date: Tue, 5 Nov 2019 09:17:19 +0900 Message-Id: <157291303888.19771.11876536314853955934.stgit@devnote2> X-Mailer: git-send-email 2.20.1 In-Reply-To: <157291299825.19771.5190465639558208592.stgit@devnote2> References: <157291299825.19771.5190465639558208592.stgit@devnote2> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Support DW_AT_const_value for variable assignment instead of location. Note that this requires ftrace supporting immediate value. Signed-off-by: Masami Hiramatsu --- tools/perf/util/probe-file.c | 7 +++++++ tools/perf/util/probe-file.h | 1 + tools/perf/util/probe-finder.c | 11 +++++++++++ 3 files changed, 19 insertions(+) diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c index a63f1a19b0e8..5003ba403345 100644 --- a/tools/perf/util/probe-file.c +++ b/tools/perf/util/probe-file.c @@ -1008,6 +1008,7 @@ enum ftrace_readme { FTRACE_README_UPROBE_REF_CTR, FTRACE_README_USER_ACCESS, FTRACE_README_MULTIPROBE_EVENT, + FTRACE_README_IMMEDIATE_VALUE, FTRACE_README_END, }; @@ -1022,6 +1023,7 @@ static struct { DEFINE_TYPE(FTRACE_README_UPROBE_REF_CTR, "*ref_ctr_offset*"), DEFINE_TYPE(FTRACE_README_USER_ACCESS, "*[u]*"), DEFINE_TYPE(FTRACE_README_MULTIPROBE_EVENT, "*Create/append/*"), + DEFINE_TYPE(FTRACE_README_IMMEDIATE_VALUE, "*\\imm-value,*"), }; static bool scan_ftrace_readme(enum ftrace_readme type) @@ -1092,3 +1094,8 @@ bool multiprobe_event_is_supported(void) { return scan_ftrace_readme(FTRACE_README_MULTIPROBE_EVENT); } + +bool immediate_value_is_supported(void) +{ + return scan_ftrace_readme(FTRACE_README_IMMEDIATE_VALUE); +} diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h index 850d1b52d60a..0dba88c0f5f0 100644 --- a/tools/perf/util/probe-file.h +++ b/tools/perf/util/probe-file.h @@ -72,6 +72,7 @@ bool kretprobe_offset_is_supported(void); bool uprobe_ref_ctr_is_supported(void); bool user_access_is_supported(void); bool multiprobe_event_is_supported(void); +bool immediate_value_is_supported(void); #else /* ! HAVE_LIBELF_SUPPORT */ static inline struct probe_cache *probe_cache__new(const char *tgt __maybe_unused, struct nsinfo *nsi __maybe_unused) { diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 9ecea45da4ca..2e3a468c8350 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -177,6 +177,17 @@ static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr, if (dwarf_attr(vr_die, DW_AT_external, &attr) != NULL) goto static_var; + /* Constant value */ + if (dwarf_attr(vr_die, DW_AT_const_value, &attr) && + immediate_value_is_supported()) { + Dwarf_Sword snum; + + dwarf_formsdata(&attr, &snum); + ret = asprintf(&tvar->value, "\\%ld", (long)snum); + + return ret < 0 ? -ENOMEM : 0; + } + /* TODO: handle more than 1 exprs */ if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL) return -EINVAL; /* Broken DIE ? */