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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 A0085C3F2CD for ; Fri, 28 Feb 2020 13:15:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F841246AF for ; Fri, 28 Feb 2020 13:15:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HMiqan1a" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725911AbgB1NPG (ORCPT ); Fri, 28 Feb 2020 08:15:06 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:39818 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725796AbgB1NPG (ORCPT ); Fri, 28 Feb 2020 08:15:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582895704; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=QgYXOPRR1ZOR3Vv3MwriHbMmIPHi0egmaHv7X5ygYH0=; b=HMiqan1aoshxs3sAwyQOXcZeePj5kPmu2+YbXX4q8+5VwwBQ125j36FJ4Obqg5jppfC+gr BHzsB1J0t9u1PPHDffAEDzdOSGjx5UsZ721FIwRIziAYNGvPf7h2fZuOsPfyzSj4VXCiH5 TG/uxVLSS9DbImrCg825BWOxCdGtaG8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-233-sKjRMc0wMRuIoVGwHuRPiQ-1; Fri, 28 Feb 2020 08:14:57 -0500 X-MC-Unique: sKjRMc0wMRuIoVGwHuRPiQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DCB1A107ACC7; Fri, 28 Feb 2020 13:14:54 +0000 (UTC) Received: from sandy.ghostprotocols.net (ovpn-112-19.phx2.redhat.com [10.3.112.19]) by smtp.corp.redhat.com (Postfix) with ESMTPS id DB91E60C18; Fri, 28 Feb 2020 13:14:53 +0000 (UTC) Received: by sandy.ghostprotocols.net (Postfix, from userid 1000) id B3B1BFD; Fri, 28 Feb 2020 10:14:50 -0300 (BRT) Date: Fri, 28 Feb 2020 10:14:50 -0300 From: Arnaldo Carvalho de Melo To: Jiri Olsa Cc: Alexei Starovoitov , Daniel Borkmann , netdev@vger.kernel.org, bpf@vger.kernel.org, Andrii Nakryiko , Yonghong Song , Song Liu , Martin KaFai Lau , Jakub Kicinski , David Miller , =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , John Fastabend , Jesper Dangaard Brouer Subject: Re: [PATCH 16/18] perf tools: Synthesize bpf_trampoline/dispatcher ksymbol event Message-ID: <20200228131450.GA4010@redhat.com> References: <20200226130345.209469-1-jolsa@kernel.org> <20200226130345.209469-17-jolsa@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200226130345.209469-17-jolsa@kernel.org> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.20 (2009-12-10) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Em Wed, Feb 26, 2020 at 02:03:43PM +0100, Jiri Olsa escreveu: > Synthesize bpf images (trampolines/dispatchers) on start, > as ksymbol events from /proc/kallsyms. Having this perf > can recognize samples from those images and perf report > and top shows them correctly. > > The rest of the ksymbol handling is already in place from > for the bpf programs monitoring, so only the initial state > was needed. Acked-by: Arnaldo Carvalho de Melo But at some point we should try and consolidate all those kallsym__parse() calls we have in tools/perf/ not to do it that many times, see below _before_ this patch: [root@five ~]# perf probe -x ~/bin/perf kallsyms__parse Added new event: probe_perf:kallsyms__parse (on kallsyms__parse in /home/acme/bin/perf) You can now use it in all perf tools, such as: perf record -e probe_perf:kallsyms__parse -aR sleep 1 [root@five ~]# perf trace -e probe_perf:kallsyms__parse/max-stack=8/ -- perf record sleep 1 0.000 perf/6444 probe_perf:kallsyms__parse(__probe_ip: 4904384) kallsyms__parse (/home/acme/bin/perf) machine__get_running_kernel_start (/home/acme/bin/perf) machine__create_kernel_maps (/home/acme/bin/perf) perf_session__new (/home/acme/bin/perf) cmd_record (/home/acme/bin/perf) run_builtin (/home/acme/bin/perf) main (/home/acme/bin/perf) __libc_start_main (/usr/lib64/libc-2.30.so) 0.124 perf/6444 probe_perf:kallsyms__parse(__probe_ip: 4904384) kallsyms__parse (/home/acme/bin/perf) machine__get_running_kernel_start (/home/acme/bin/perf) machine__create_kernel_maps (/home/acme/bin/perf) perf_session__new (/home/acme/bin/perf) cmd_record (/home/acme/bin/perf) run_builtin (/home/acme/bin/perf) main (/home/acme/bin/perf) __libc_start_main (/usr/lib64/libc-2.30.so) 15.489 perf/6444 probe_perf:kallsyms__parse(__probe_ip: 4904384) kallsyms__parse (/home/acme/bin/perf) machine__create_kernel_maps (/home/acme/bin/perf) perf_session__new (/home/acme/bin/perf) cmd_record (/home/acme/bin/perf) run_builtin (/home/acme/bin/perf) main (/home/acme/bin/perf) __libc_start_main (/usr/lib64/libc-2.30.so) [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.019 MB perf.data (7 samples) ] [root@five ~]# - Arnaldo > perf report output: > > # Overhead Command Shared Object Symbol > > 12.37% test_progs [kernel.vmlinux] [k] entry_SYSCALL_64 > 11.80% test_progs [kernel.vmlinux] [k] syscall_return_via_sysret > 9.63% test_progs bpf_prog_bcf7977d3b93787c_prog2 [k] bpf_prog_bcf7977d3b93787c_prog2 > 6.90% test_progs bpf_trampoline_24456 [k] bpf_trampoline_24456 > 6.36% test_progs [kernel.vmlinux] [k] memcpy_erms > > Signed-off-by: Jiri Olsa > --- > tools/perf/util/bpf-event.c | 98 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 98 insertions(+) > > diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c > index a3207d900339..120ec547ae75 100644 > --- a/tools/perf/util/bpf-event.c > +++ b/tools/perf/util/bpf-event.c > @@ -6,6 +6,9 @@ > #include > #include > #include > +#include > +#include > +#include > #include "bpf-event.h" > #include "debug.h" > #include "dso.h" > @@ -290,11 +293,87 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, > return err ? -1 : 0; > } > > +struct kallsyms_parse { > + union perf_event *event; > + perf_event__handler_t process; > + struct machine *machine; > + struct perf_tool *tool; > +}; > + > +static int > +process_bpf_image(char *name, u64 addr, struct kallsyms_parse *data) > +{ > + struct machine *machine = data->machine; > + union perf_event *event = data->event; > + struct perf_record_ksymbol *ksymbol; > + u32 size; > + > + ksymbol = &event->ksymbol; > + > + /* > + * The bpf image (trampoline/dispatcher) size is aligned to > + * page, while it starts little bit after the page boundary. > + */ > + size = page_size - (addr - PERF_ALIGN(addr, page_size)); > + > + *ksymbol = (struct perf_record_ksymbol) { > + .header = { > + .type = PERF_RECORD_KSYMBOL, > + .size = offsetof(struct perf_record_ksymbol, name), > + }, > + .addr = addr, > + .len = size, > + .ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF, > + .flags = 0, > + }; > + > + strncpy(ksymbol->name, name, KSYM_NAME_LEN); > + ksymbol->header.size += PERF_ALIGN(strlen(name) + 1, sizeof(u64)); > + memset((void *) event + event->header.size, 0, machine->id_hdr_size); > + event->header.size += machine->id_hdr_size; > + > + return perf_tool__process_synth_event(data->tool, event, machine, > + data->process); > +} > + > +static int > +kallsyms_process_symbol(void *data, const char *_name, > + char type __maybe_unused, u64 start) > +{ > + char *module, *name; > + unsigned long id; > + int err = 0; > + > + module = strchr(_name, '\t'); > + if (!module) > + return 0; > + > + /* We are going after [bpf] module ... */ > + if (strcmp(module + 1, "[bpf]")) > + return 0; > + > + name = memdup(_name, (module - _name) + 1); > + if (!name) > + return -ENOMEM; > + > + name[module - _name] = 0; > + > + /* .. and only for trampolines and dispatchers */ > + if ((sscanf(name, "bpf_trampoline_%lu", &id) == 1) || > + (sscanf(name, "bpf_dispatcher_%lu", &id) == 1)) > + err = process_bpf_image(name, start, data); > + > + free(name); > + return err; > +} > + > int perf_event__synthesize_bpf_events(struct perf_session *session, > perf_event__handler_t process, > struct machine *machine, > struct record_opts *opts) > { > + const char *kallsyms_filename = "/proc/kallsyms"; > + struct kallsyms_parse arg; > union perf_event *event; > __u32 id = 0; > int err; > @@ -303,6 +382,8 @@ int perf_event__synthesize_bpf_events(struct perf_session *session, > event = malloc(sizeof(event->bpf) + KSYM_NAME_LEN + machine->id_hdr_size); > if (!event) > return -1; > + > + /* Synthesize all the bpf programs in system. */ > while (true) { > err = bpf_prog_get_next_id(id, &id); > if (err) { > @@ -335,6 +416,23 @@ int perf_event__synthesize_bpf_events(struct perf_session *session, > break; > } > } > + > + /* Synthesize all the bpf images - trampolines/dispatchers. */ > + if (symbol_conf.kallsyms_name != NULL) > + kallsyms_filename = symbol_conf.kallsyms_name; > + > + arg = (struct kallsyms_parse) { > + .event = event, > + .process = process, > + .machine = machine, > + .tool = session->tool, > + }; > + > + if (kallsyms__parse(kallsyms_filename, &arg, kallsyms_process_symbol)) { > + pr_err("%s: failed to synthesize bpf images: %s\n", > + __func__, strerror(errno)); > + } > + > free(event); > return err; > } > -- > 2.24.1