From 48bce2e8f0d787342f3e0f86335460fa25e8ac8f Mon Sep 17 00:00:00 2001 From: Rafael Roquetto Date: Wed, 1 Feb 2017 17:32:13 -0200 Subject: Support for LTTNG and ETW tracing This commit introduces minimal support for instrumentation within Qt. Currently, only LTTNG/Linux and ETW/Windows are supported. Change-Id: I59b48cf83acf5532a998bb493e6379e9177e14c8 Reviewed-by: Oswald Buddenhagen Reviewed-by: Shawn Rutledge Reviewed-by: Thiago Macieira --- src/corelib/global/qtrace_p.h | 126 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 126 insertions(+) create mode 100644 src/corelib/global/qtrace_p.h (limited to 'src/corelib/global/qtrace_p.h') diff --git a/src/corelib/global/qtrace_p.h b/src/corelib/global/qtrace_p.h new file mode 100644 index 0000000000..ab8fc14af5 --- /dev/null +++ b/src/corelib/global/qtrace_p.h @@ -0,0 +1,126 @@ +/**************************************************************************** +** +** Copyright (C) 2017 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Rafael Roquetto +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the QtCore module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and The Qt Company. For licensing terms +** and conditions see https://www.qt.io/terms-conditions. For further +** information use the contact form at https://www.qt.io/contact-us. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 3 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL3 included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 3 requirements +** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 2.0 or (at your option) the GNU General +** Public license version 3 or any later version approved by the KDE Free +** Qt Foundation. The licenses are as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 +** included in the packaging of this file. Please review the following +** information to ensure the GNU General Public License requirements will +** be met: https://www.gnu.org/licenses/gpl-2.0.html and +** https://www.gnu.org/licenses/gpl-3.0.html. +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#ifndef QTRACE_P_H +#define QTRACE_P_H + +// +// W A R N I N G +// ------------- +// +// This file is not part of the Qt API. It exists purely as an +// implementation detail. This header file may change from version to +// version without notice, or even be removed. +// +// We mean it. +// + +/* + * The Qt tracepoints API consists of only three macros: + * + * - Q_TRACE(tracepoint, args...) + * Fires 'tracepoint' if it is enabled. + * + * - Q_UNCONDITIONAL_TRACE(tracepoint, args...) + * Fires 'tracepoint' unconditionally: no check is performed to query + * whether 'tracepoint' is enabled. + * + * - Q_TRACE_ENABLED(tracepoint) + * Returns 'true' if 'tracepoint' is enabled; false otherwise. + * + * When using LTTNG, Q_TRACE, Q_UNCONDITIONAL_TRACE and Q_TRACE_ENABLED map + * ultimately to tracepoint(), do_tracepoint() and tracepoint_enabled(), + * respectively, described on the lttng-ust manpage (man 3 lttng-ust). + * + * On ETW, Q_TRACE() and Q_UNCONDITIONAL_TRACE() are equivalent, ultimately + * amounting to a call to TraceLoggingWrite(), whereas Q_TRACE_ENABLED() + * wraps around TraceLoggingProviderEnabled(). + * + * A tracepoint provider is defined in a separate file, that follows the + * following format: + * + * tracepoint_name(arg_type arg_name, ...) + * + * For instance: + * + * qcoreapplication_ctor(int argc, const char * const argv) + * qcoreapplication_foo(int argc, const char[10] argv) + * qcoreapplication_baz(const char[len] some_string, unsigned int len) + * qcoreapplication_qstring(const QString &foo) + * qcoreapplication_qrect(const QRect &rect) + * + * The provider file is then parsed by src/tools/tracegen, which can be + * switched to output either ETW or LTTNG tracepoint definitions. The provider + * name is deduced to be basename(provider_file). + * + * To use the above (inside qtcore), you need to include + * . After that, the following call becomes + * possible: + * + * Q_TRACE(qcoreapplication_qrect, myRect); + * + * Currently, all C++ primitive non-pointer types are supported for + * arguments. Additionally, char * is supported, and is assumed to + * be a NULL-terminated string. Finally, the following subset of Qt types also + * currently supported: + * + * - QString + * - QByteArray + * - QUrl + * - QRect + * + * Dynamic arrays are supported using the syntax illustrated by + * qcoreapplication_baz above. + */ + +QT_BEGIN_NAMESPACE + +#if defined(Q_TRACEPOINT) && !defined(QT_BOOTSTRAPPED) +# define Q_TRACE(x, ...) QtPrivate::trace_ ## x(__VA_ARGS__) +# define Q_UNCONDITIONAL_TRACE(x, ...) QtPrivate::do_trace_ ## x(__VA_ARGS__) +# define Q_TRACE_ENABLED(x) QtPrivate::trace_ ## x ## _enabled() +#else +# define Q_TRACE(x, ...) +# define Q_UNCONDITIONAL_TRACE(x, ...) +# define Q_TRACE_ENABLED(x) false +#endif // defined(Q_TRACEPOINT) && !defined(QT_BOOTSTRAPPED) + +QT_END_NAMESPACE + +#endif // QTRACE_P_H -- cgit v1.2.3