From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751906AbbJBU2o (ORCPT ); Fri, 2 Oct 2015 16:28:44 -0400 Received: from casper.infradead.org ([85.118.1.10]:49809 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751216AbbJBU0D (ORCPT ); Fri, 2 Oct 2015 16:26:03 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Masami Hiramatsu , Jiri Olsa , Namhyung Kim , Wang Nan , Arnaldo Carvalho de Melo Subject: [PATCH 08/10] perf probe: Allow probing on kmodules without dwarf Date: Fri, 2 Oct 2015 17:25:43 -0300 Message-Id: <1443817545-8551-9-git-send-email-acme@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1443817545-8551-1-git-send-email-acme@kernel.org> References: <1443817545-8551-1-git-send-email-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masami Hiramatsu Allow probing on kernel modules when 'perf' is built without debuginfo support. Currently perf-probe --module requires linking with libdw, but this doesn't make sense. E.g. ---- # make NO_DWARF=1 # ./perf probe -m pcspkr pcspkr_event%return Error: unknown switch `m' ---- With this patch ---- # ./perf probe -m pcspkr pcspkr_event%return Added new event: probe:pcspkr_event (on pcspkr_event%return in pcspkr) You can now use it in all perf tools, such as: perf record -e probe:pcspkr_event -aR sleep 1 ---- Signed-off-by: Masami Hiramatsu Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/r/20151002125832.18617.78721.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-probe.c | 8 +++----- tools/perf/util/probe-event.c | 8 +++++--- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c index f7882ae9ebc6..530c3a28a58c 100644 --- a/tools/perf/builtin-probe.c +++ b/tools/perf/builtin-probe.c @@ -182,10 +182,8 @@ static int opt_set_target(const struct option *opt, const char *str, if (str) { if (!strcmp(opt->long_name, "exec")) params.uprobes = true; -#ifdef HAVE_DWARF_SUPPORT else if (!strcmp(opt->long_name, "module")) params.uprobes = false; -#endif else return ret; @@ -490,9 +488,6 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) "file", "vmlinux pathname"), OPT_STRING('s', "source", &symbol_conf.source_prefix, "directory", "path to kernel source"), - OPT_CALLBACK('m', "module", NULL, "modname|path", - "target module name (for online) or path (for offline)", - opt_set_target), OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines, "Don't search inlined functions"), #endif @@ -509,6 +504,9 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) opt_set_filter), OPT_CALLBACK('x', "exec", NULL, "executable|path", "target executable name or path", opt_set_target), + OPT_CALLBACK('m', "module", NULL, "modname|path", + "target module name (for online) or path (for offline)", + opt_set_target), OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle, "Enable symbol demangling"), OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel, diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 3010abc071ff..b51a8bfb40f9 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -2543,7 +2543,8 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, goto out; } - if (!pev->uprobes && !pp->retprobe) { + /* Note that the symbols in the kmodule are not relocated */ + if (!pev->uprobes && !pp->retprobe && !pev->target) { reloc_sym = kernel_get_ref_reloc_sym(); if (!reloc_sym) { pr_warning("Relocated base symbol is not found!\n"); @@ -2580,8 +2581,9 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, } /* Add one probe point */ tp->address = map->unmap_ip(map, sym->start) + pp->offset; - /* If we found a wrong one, mark it by NULL symbol */ - if (!pev->uprobes && + + /* Check the kprobe (not in module) is within .text */ + if (!pev->uprobes && !pev->target && kprobe_warn_out_range(sym->name, tp->address)) { tp->symbol = NULL; /* Skip it */ skipped++; -- 2.1.0