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=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 AED3FC2D0E4 for ; Tue, 17 Nov 2020 12:44:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43FCC2222B for ; Tue, 17 Nov 2020 12:44:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="csuMErfk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726809AbgKQMom (ORCPT ); Tue, 17 Nov 2020 07:44:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:48966 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725779AbgKQMol (ORCPT ); Tue, 17 Nov 2020 07:44:41 -0500 Received: from quaco.ghostprotocols.net (unknown [179.97.37.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 49EC822203; Tue, 17 Nov 2020 12:44:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605617080; bh=6ZPOxKQN7EfoEKtx0si1zr5srH8ZGaPNaNtUAepHEEw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=csuMErfks4eN5jKlRXEV1mTFIQZ6/9ELdix9VvaxRl8HMlZ6Ypv1zxY2FsETVNZOP qWqlAwKTkm7lD83Wvc+z+7JUov6w/9tZpYy7bEpv+T59d6xVMtuQGy4NSf18QcorHr F/nY0YIc2AXQnWcYS5f+udKAxCuPmRH1ZOArcGrM= Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id D5C9440E29; Tue, 17 Nov 2020 09:44:37 -0300 (-03) Date: Tue, 17 Nov 2020 09:44:37 -0300 From: Arnaldo Carvalho de Melo To: Jiri Olsa Cc: lkml , Peter Zijlstra , Ingo Molnar , Mark Rutland , Namhyung Kim , Alexander Shishkin , Michael Petlan , Song Liu , Ian Rogers , Stephane Eranian , Alexey Budankov , Andi Kleen , Adrian Hunter Subject: Re: [PATCH 13/24] perf tools: Allow mmap2 event to synthesize kernel image Message-ID: <20201117124437.GO614220@kernel.org> References: <20201117110053.1303113-1-jolsa@kernel.org> <20201117110053.1303113-14-jolsa@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201117110053.1303113-14-jolsa@kernel.org> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, Nov 17, 2020 at 12:00:42PM +0100, Jiri Olsa escreveu: > Allow mmap2 event to synthesize kernel image, > so we can synthesize kernel build id data in > following changes. > > It's enabled by new symbol_conf.buildid_mmap2 > bool, which will be switched in following > changes. Why make this an option? MMAP2 goes back years: 13d7a2410fa637f45 (Stephane Eranian 2013-08-21 12:10:24 +0200 904) * The MMAP2 records are an augmented version of MMAP, they add 13d7a2410fa637f45 (Stephane Eranian 2013-08-21 12:10:24 +0200 905) * maj, min, ino numbers to be used to uniquely identify each mapping Also we unconditionally generate MMAP2 events if the kernel supports it, from evsel__config(): attr->mmap = track; attr->mmap2 = track && !perf_missing_features.mmap2; So perhaps we should reuse that logic? I.e. use mmap2 if the kernel supports it? - Arnaldo > Signed-off-by: Jiri Olsa > --- > tools/perf/util/symbol_conf.h | 3 ++- > tools/perf/util/synthetic-events.c | 40 ++++++++++++++++++++---------- > 2 files changed, 29 insertions(+), 14 deletions(-) > > diff --git a/tools/perf/util/symbol_conf.h b/tools/perf/util/symbol_conf.h > index b916afb95ec5..b18f9c8dbb75 100644 > --- a/tools/perf/util/symbol_conf.h > +++ b/tools/perf/util/symbol_conf.h > @@ -42,7 +42,8 @@ struct symbol_conf { > report_block, > report_individual_block, > inline_name, > - disable_add2line_warn; > + disable_add2line_warn, > + buildid_mmap2; > const char *vmlinux_name, > *kallsyms_name, > *source_prefix, > diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c > index 8a23391558cf..872df6d6dbef 100644 > --- a/tools/perf/util/synthetic-events.c > +++ b/tools/perf/util/synthetic-events.c > @@ -988,11 +988,12 @@ static int __perf_event__synthesize_kernel_mmap(struct perf_tool *tool, > perf_event__handler_t process, > struct machine *machine) > { > - size_t size; > + union perf_event *event; > + size_t size = symbol_conf.buildid_mmap2 ? > + sizeof(event->mmap2) : sizeof(event->mmap); > struct map *map = machine__kernel_map(machine); > struct kmap *kmap; > int err; > - union perf_event *event; > > if (map == NULL) > return -1; > @@ -1006,7 +1007,7 @@ static int __perf_event__synthesize_kernel_mmap(struct perf_tool *tool, > * available use this, and after it is use this as a fallback for older > * kernels. > */ > - event = zalloc((sizeof(event->mmap) + machine->id_hdr_size)); > + event = zalloc(size + machine->id_hdr_size); > if (event == NULL) { > pr_debug("Not enough memory synthesizing mmap event " > "for kernel modules\n"); > @@ -1023,16 +1024,29 @@ static int __perf_event__synthesize_kernel_mmap(struct perf_tool *tool, > event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL; > } > > - size = snprintf(event->mmap.filename, sizeof(event->mmap.filename), > - "%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1; > - size = PERF_ALIGN(size, sizeof(u64)); > - event->mmap.header.type = PERF_RECORD_MMAP; > - event->mmap.header.size = (sizeof(event->mmap) - > - (sizeof(event->mmap.filename) - size) + machine->id_hdr_size); > - event->mmap.pgoff = kmap->ref_reloc_sym->addr; > - event->mmap.start = map->start; > - event->mmap.len = map->end - event->mmap.start; > - event->mmap.pid = machine->pid; > + if (symbol_conf.buildid_mmap2) { > + size = snprintf(event->mmap2.filename, sizeof(event->mmap2.filename), > + "%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1; > + size = PERF_ALIGN(size, sizeof(u64)); > + event->mmap2.header.type = PERF_RECORD_MMAP2; > + event->mmap2.header.size = (sizeof(event->mmap2) - > + (sizeof(event->mmap2.filename) - size) + machine->id_hdr_size); > + event->mmap2.pgoff = kmap->ref_reloc_sym->addr; > + event->mmap2.start = map->start; > + event->mmap2.len = map->end - event->mmap.start; > + event->mmap2.pid = machine->pid; > + } else { > + size = snprintf(event->mmap.filename, sizeof(event->mmap.filename), > + "%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1; > + size = PERF_ALIGN(size, sizeof(u64)); > + event->mmap.header.type = PERF_RECORD_MMAP; > + event->mmap.header.size = (sizeof(event->mmap) - > + (sizeof(event->mmap.filename) - size) + machine->id_hdr_size); > + event->mmap.pgoff = kmap->ref_reloc_sym->addr; > + event->mmap.start = map->start; > + event->mmap.len = map->end - event->mmap.start; > + event->mmap.pid = machine->pid; > + } > > err = perf_tool__process_synth_event(tool, event, machine, process); > free(event); > -- > 2.26.2 > -- - Arnaldo