From patchwork Thu Jul 23 13:29:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe de Dinechin X-Patchwork-Id: 11681023 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B8132138A for ; Thu, 23 Jul 2020 13:32:32 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7DCBE20709 for ; Thu, 23 Jul 2020 13:32:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QrxhBLBS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7DCBE20709 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:51568 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jybKo-0006oD-Uw for patchwork-qemu-devel@patchwork.kernel.org; Thu, 23 Jul 2020 09:32:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53604) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jybHs-0003LS-Fn for qemu-devel@nongnu.org; Thu, 23 Jul 2020 09:29:28 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:20109 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jybHo-0005PW-73 for qemu-devel@nongnu.org; Thu, 23 Jul 2020 09:29:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595510963; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=69upIEPR5Rocv0K1dpgi2tOtNkX5hv5N+Y3yZWXm1yc=; b=QrxhBLBSSGAs1RMHQfHcuLLQV+FcGUz7A9E0Pe55jF8BrUe209pUvSt/w0aJg7LyXX6oy1 9Dz7Hg9kkXktxOWHxXatlJtKeK++bIkaqnZk9bpuy1qQWdxgtpa17qXtLyuks5+lolUD4y c/IeU0psgXch//0ltYNYHyg/fJwBa2s= 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-449-RvDGOi_xOhG01FzAFjr62g-1; Thu, 23 Jul 2020 09:29:19 -0400 X-MC-Unique: RvDGOi_xOhG01FzAFjr62g-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6C7F48014D7; Thu, 23 Jul 2020 13:29:18 +0000 (UTC) Received: from turbo.com (ovpn-113-141.ams2.redhat.com [10.36.113.141]) by smtp.corp.redhat.com (Postfix) with ESMTP id 801D85DEBA; Thu, 23 Jul 2020 13:29:16 +0000 (UTC) From: Christophe de Dinechin To: qemu-devel@nongnu.org Subject: [PATCH v4 1/2] trace: Add support for recorder back-end Date: Thu, 23 Jul 2020 15:29:02 +0200 Message-Id: <20200723132903.1980743-2-dinechin@redhat.com> In-Reply-To: <20200723132903.1980743-1-dinechin@redhat.com> References: <20200723132903.1980743-1-dinechin@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.81; envelope-from=dinechin@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/23 02:26:42 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michael Tokarev , Markus Armbruster , "Dr. David Alan Gilbert" , Stefan Hajnoczi , Christophe de Dinechin , Laurent Vivier Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" The recorder library provides support for low-cost continuous recording of events, which can then be replayed. This makes it possible to collect data after the fact, for example to show the events that led to a crash or unexpected condition. In this series, minimal recorder support in qemu is implemented using the existing tracing interface. For each trace, a corresponding recorder is created with a generic name and a default size of 8 entries. In addition, it is possible to explicitly enable recorders that are not qemu traces, for example in order to use actually record events rather than trace them, or to use the real-time graphing capabilities. For that reason, a limited set of recorder-related macros are defined as no-ops even if the recorder trace backend is not configured. Recorder-specific features, notably the ability to perform a post-mortem dump and to group traces by topic, are not integrated in this series, as doing so would require modifying the trace infrastructure, which is a non-objective here. This may be the topic of later series if there is any interest for it. HMP COMMAND: The 'recorder' hmp command has been added, which supports two sub-commands: * recorder dump: Dump the current state of the recorder. You can give that command a recorder name, to only dump that recorder. * recorder trace: Set traces using the recorder_trace_set() syntax. You can use "recorder trace help" to list all available recorders. Signed-off-by: Christophe de Dinechin --- MAINTAINERS | 1 + configure | 14 ++++++++ hmp-commands.hx | 23 +++++++++++- monitor/misc.c | 25 +++++++++++++ scripts/tracetool/backend/recorder.py | 52 +++++++++++++++++++++++++++ trace/Makefile.objs | 1 + trace/control.c | 5 +++ trace/recorder.c | 27 ++++++++++++++ trace/recorder.h | 32 +++++++++++++++++ util/module.c | 6 ++++ 10 files changed, 185 insertions(+), 1 deletion(-) create mode 100644 scripts/tracetool/backend/recorder.py create mode 100644 trace/recorder.c create mode 100644 trace/recorder.h diff --git a/MAINTAINERS b/MAINTAINERS index 3395abd4e1..764b5915d7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2484,6 +2484,7 @@ F: stubs/ Tracing M: Stefan Hajnoczi S: Maintained +R: Christophe de Dinechin F: trace/ F: trace-events F: docs/qemu-option-trace.rst.inc diff --git a/configure b/configure index 4bd80ed507..3770ff873d 100755 --- a/configure +++ b/configure @@ -7761,6 +7761,20 @@ fi if have_backend "log"; then echo "CONFIG_TRACE_LOG=y" >> $config_host_mak fi +if have_backend "recorder"; then + recorder_minver="1.0.10" + if $pkg_config --atleast-version=$recorder_minver recorder ; then + recorder_cflags="$($pkg_config --cflags recorder)" + recorder_libs="$($pkg_config --libs recorder)" + LIBS="$recorder_libs $LIBS" + libs_qga="$recorder_libs $libs_qga" + QEMU_CFLAGS="$QEMU_CFLAGS $recorder_cflags" + zstd="yes" + echo "CONFIG_TRACE_RECORDER=y" >> $config_host_mak + else + feature_not_found "recorder" "Install recorder-devel package" + fi +fi if have_backend "ust"; then echo "CONFIG_TRACE_UST=y" >> $config_host_mak fi diff --git a/hmp-commands.hx b/hmp-commands.hx index d548a3ab74..f164ff6d65 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -302,6 +302,28 @@ SRST Open, close, or flush the trace file. If no argument is given, the status of the trace file is displayed. ERST +#endif + +#if defined(CONFIG_TRACE_RECORDER) + { + .name = "recorder", + .args_type = "op:s?,arg:s?", + .params = "trace|dump [arg]", + .help = "trace selected recorders or print recorder dump", + .cmd = hmp_recorder, + }, + +SRST +``trace`` *cmds* + Activate or deactivate tracing for individual recorder traces. + See recorder_trace_set(3) for the syntax of *cmds* + For example, to activate trace ``foo`` and disable alll traces + ending in ``_warning``, use ``foo:.*_warning=0``. + Using ``help`` will list available traces and their current setting. +``dump`` [*name*] + Dump the recorder. If *name* is given, only the specific named recorder + will be dumped. +ERST #endif { @@ -1828,4 +1850,3 @@ ERST .sub_table = hmp_info_cmds, .flags = "p", }, - diff --git a/monitor/misc.c b/monitor/misc.c index e847b58a8c..aff72158d7 100644 --- a/monitor/misc.c +++ b/monitor/misc.c @@ -60,6 +60,7 @@ #ifdef CONFIG_TRACE_SIMPLE #include "trace/simple.h" #endif +#include "trace/recorder.h" #include "exec/memory.h" #include "exec/exec-all.h" #include "qemu/option.h" @@ -226,6 +227,30 @@ static void hmp_trace_file(Monitor *mon, const QDict *qdict) } #endif +#ifdef CONFIG_TRACE_RECORDER +static void hmp_recorder(Monitor *mon, const QDict *qdict) +{ + const char *op = qdict_get_try_str(qdict, "op"); + const char *arg = qdict_get_try_str(qdict, "arg"); + + if (!op) { + monitor_printf(mon, "missing recorder command\"%s\"\n", op); + help_cmd(mon, "recorder"); + } else if (!strcmp(op, "trace")) { + recorder_trace_set(arg); + } else if (!strcmp(op, "dump")) { + if (!arg || !*arg) { + recorder_dump(); + } else { + recorder_dump_for(arg); + } + } else { + monitor_printf(mon, "unexpected recorder command \"%s\"\n", op); + help_cmd(mon, "recorder"); + } +} +#endif + static void hmp_info_help(Monitor *mon, const QDict *qdict) { help_cmd(mon, "info"); diff --git a/scripts/tracetool/backend/recorder.py b/scripts/tracetool/backend/recorder.py new file mode 100644 index 0000000000..82d983ff31 --- /dev/null +++ b/scripts/tracetool/backend/recorder.py @@ -0,0 +1,52 @@ +# -*- coding: utf-8 -*- + +""" +Trace back-end for recorder library +""" + +__author__ = "Christophe de Dinechin " +__copyright__ = "Copyright 2020, Christophe de Dinechin and Red Hat" +__license__ = "GPL version 2 or (at your option) any later version" + +__maintainer__ = "Christophe de Dinechin" +__email__ = "christophe@dinechin.org" + + +from tracetool import out + +PUBLIC = True + +def generate_h_begin(events, group): + out('#include ', '') + + for event in events: + out('RECORDER_DECLARE(%(name)s);', name=event.name) + + +def generate_h(event, group): + argnames = ", ".join(event.args.names()) + if len(event.args) > 0: + argnames = ", " + argnames + + out(' record(%(event)s, %(fmt)s %(argnames)s);', + event=event.name, + fmt=event.fmt.rstrip("\n"), + argnames=argnames) + + +def generate_h_backend_dstate(event, group): + out(' RECORDER_TWEAK(%(event_id)s) || \\', event_id=event.name) + +def generate_c_begin(events, group): + out('#include "qemu/osdep.h"', + '#include "trace/control.h"', + '#include "trace/simple.h"', + '#include ', + '') + + for event in events: + out('RECORDER_DEFINE(%(name)s, 8,', + ' "Tracetool recorder for %(api)s(%(args)s)");', + name=event.name, + api=event.api(), + args=event.args) diff --git a/trace/Makefile.objs b/trace/Makefile.objs index c544509adf..13667e98d5 100644 --- a/trace/Makefile.objs +++ b/trace/Makefile.objs @@ -54,6 +54,7 @@ $(obj)/generated-tcg-tracers.h-timestamp: $(SRC_PATH)/trace-events $(BUILD_DIR)/ util-obj-$(CONFIG_TRACE_SIMPLE) += simple.o util-obj-$(CONFIG_TRACE_FTRACE) += ftrace.o +util-obj-$(CONFIG_TRACE_RECORDER) += recorder.o util-obj-y += control.o obj-y += control-target.o util-obj-y += qmp.o diff --git a/trace/control.c b/trace/control.c index 2ffe000818..71f170f73b 100644 --- a/trace/control.c +++ b/trace/control.c @@ -23,6 +23,7 @@ #ifdef CONFIG_TRACE_SYSLOG #include #endif +#include "trace/recorder.h" #include "qapi/error.h" #include "qemu/error-report.h" #include "qemu/config-file.h" @@ -282,6 +283,10 @@ bool trace_init_backends(void) openlog(NULL, LOG_PID, LOG_DAEMON); #endif +#ifdef CONFIG_TRACE_RECORDER + recorder_trace_init(); +#endif + return true; } diff --git a/trace/recorder.c b/trace/recorder.c new file mode 100644 index 0000000000..c47abc363c --- /dev/null +++ b/trace/recorder.c @@ -0,0 +1,27 @@ +/* + * Recorder-based trace backend + * + * Copyright Red Hat 2020 + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" +#include "trace/recorder.h" + +RECORDER_CONSTRUCTOR +void recorder_trace_init(void) +{ + const char *traces = getenv("RECORDER_TRACES"); + recorder_trace_set(traces); + + /* + * Allow a dump in case we receive some unhandled signal + * For example, send USR2 to a hung process to get a dump + */ + if (traces) { + recorder_dump_on_common_signals(0, 0); + } +} diff --git a/trace/recorder.h b/trace/recorder.h new file mode 100644 index 0000000000..e69f633437 --- /dev/null +++ b/trace/recorder.h @@ -0,0 +1,32 @@ +/* + * Recorder-based trace backend + * + * Copyright Red Hat 2020 + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#ifndef TRACE_RECORDER_H +#define TRACE_RECORDER_H + +#ifdef CONFIG_TRACE_RECORDER + +#include + +extern void recorder_trace_init(void); + +#else + +/* Disable recorder macros */ +#define RECORDER(Name, Size, Description) +#define RECORDER_DEFINE(Name, Size, Description) +#define RECORDER_DECLARE(Name) +#define RECORD(Name, ...) +#define record(Name, ...) +#define recorder_trace_init() + +#endif /* CONFIG_TRACE_RECORDER */ + +#endif /* TRACE_RECORDER_H */ diff --git a/util/module.c b/util/module.c index 0ab00851f0..03179a09aa 100644 --- a/util/module.c +++ b/util/module.c @@ -22,6 +22,8 @@ #ifdef CONFIG_MODULE_UPGRADES #include "qemu-version.h" #endif +#include "trace/recorder.h" + typedef struct ModuleEntry { @@ -150,6 +152,10 @@ static int module_load_file(const char *fname) g_module_close(g_module); ret = -EINVAL; } else { +#ifdef CONFIG_TRACE_RECORDER + /* New recorders may have been pulled in, activate them if necessary */ + recorder_trace_init(); +#endif QTAILQ_FOREACH(e, &dso_init_list, node) { e->init(); register_module_init(e->init, e->type);