Add the skeleton Linux perf events counter for QtTest

Currently, it only prints "perf available" if you use the -perf option
and perf is available. The implementation comes in the next commits.

Change-Id: Ic6cdee70e21df25780799a4bc31ca2c2d923b9f8
Reviewed-by: Jason McDonald <macadder1@gmail.com>

src/testlib/qbenchmark.cpp

@@ -87,6 +87,10 @@ QBenchmarkMeasurerBase * QBenchmarkGlobalData::createMeasurer()
     } else if (mode_ == CallgrindChildProcess || mode_ == CallgrindParentProcess) {
         measurer = new QBenchmarkCallgrindMeasurer;
 #endif
+#ifdef QTESTLIB_USE_PERF_EVENTS
+    } else if (mode_ == PerfCounter) {
+        measurer = new QBenchmarkPerfEventsMeasurer;
+#endif
 #ifdef HAVE_TICK_COUNTER
     } else if (mode_ == TickCounter) {
         measurer = new QBenchmarkTickMeasurer;

src/testlib/qbenchmark_p.h

@@ -63,12 +63,21 @@
 #undef QTESTLIB_USE_VALGRIND
 #endif
 
+#if defined(Q_OS_LINUX) && !defined(QT_LINUXBASE)
+#define QTESTLIB_USE_PERF_EVENTS
+#else
+#undef QTESTLIB_USE_PERF_EVENTS
+#endif
+
 #include <QtTest/private/qbenchmarkmeasurement_p.h>
 #include <QtCore/QMap>
 #include <QtTest/qtest_global.h>
 #ifdef QTESTLIB_USE_VALGRIND
 #include <QtTest/private/qbenchmarkvalgrind_p.h>
 #endif
+#ifdef QTESTLIB_USE_PERF_EVENTS
+#include <QtTest/private/qbenchmarkperfevents_p.h>
+#endif
 #include <QtTest/private/qbenchmarkevent_p.h>
 #include <QtTest/private/qbenchmarkmetric_p.h>
 
@@ -137,7 +146,7 @@ public:
 
     QBenchmarkGlobalData();
     ~QBenchmarkGlobalData();
-    enum Mode { WallTime, CallgrindParentProcess, CallgrindChildProcess, TickCounter, EventCounter };
+    enum Mode { WallTime, CallgrindParentProcess, CallgrindChildProcess, PerfCounter, TickCounter, EventCounter };
     void setMode(Mode mode);
     Mode mode() const { return mode_; }
     QBenchmarkMeasurerBase *createMeasurer();

src/testlib/qbenchmarkperfevents.cpp

@@ -0,0 +1,115 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Intel Corporation.
+** Contact: http://www.qt-project.org/legal
+**
+** 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qbenchmarkperfevents_p.h"
+#include "qbenchmark_p.h"
+
+#ifdef QTESTLIB_USE_PERF_EVENTS
+
+#include <sys/types.h>
+#include <errno.h>
+
+#include <sys/syscall.h>
+
+#include "3rdparty/linux_perf_event_p.h"
+
+QT_BEGIN_NAMESPACE
+
+
+static int perf_event_open(perf_event_attr *attr, pid_t pid, int cpu, int group_fd, unsigned long flags)
+{
+    return syscall(SYS_perf_event_open, attr, pid, cpu, group_fd, flags);
+}
+
+bool QBenchmarkPerfEventsMeasurer::isAvailable()
+{
+    // this generates an EFAULT because attr == NULL if perf_event_open is available
+    // if the kernel is too old, it generates ENOSYS
+    return perf_event_open(0, 0, 0, 0, 0) == -1 && errno != ENOSYS;
+}
+
+QBenchmarkPerfEventsMeasurer::QBenchmarkPerfEventsMeasurer()
+{
+}
+
+QBenchmarkPerfEventsMeasurer::~QBenchmarkPerfEventsMeasurer()
+{
+}
+
+void QBenchmarkPerfEventsMeasurer::init()
+{
+}
+
+void QBenchmarkPerfEventsMeasurer::start()
+{
+}
+
+qint64 QBenchmarkPerfEventsMeasurer::checkpoint()
+{
+}
+
+qint64 QBenchmarkPerfEventsMeasurer::stop()
+{
+}
+
+bool QBenchmarkPerfEventsMeasurer::isMeasurementAccepted(qint64)
+{
+    return true;
+}
+
+int QBenchmarkPerfEventsMeasurer::adjustIterationCount(int)
+{
+    return 1;
+}
+
+int QBenchmarkPerfEventsMeasurer::adjustMedianCount(int)
+{
+    return 1;
+}
+
+QTest::QBenchmarkMetric QBenchmarkPerfEventsMeasurer::metricType()
+{
+    return QTest::Events;
+}
+
+#endif
+
+QT_END_NAMESPACE

src/testlib/qbenchmarkperfevents_p.h

@@ -0,0 +1,82 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Intel Corporation.
+** Contact: http://www.qt-project.org/legal
+**
+** 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QBENCHMARKPERFEVENTS_P_H
+#define QBENCHMARKPERFEVENTS_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.
+//
+
+#include <QtTest/private/qbenchmarkmeasurement_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QBenchmarkPerfEventsMeasurer : public QBenchmarkMeasurerBase
+{
+public:
+    QBenchmarkPerfEventsMeasurer();
+    ~QBenchmarkPerfEventsMeasurer();
+    virtual void init();
+    virtual void start();
+    virtual qint64 checkpoint();
+    virtual qint64 stop();
+    virtual bool isMeasurementAccepted(qint64 measurement);
+    virtual int adjustIterationCount(int suggestion);
+    virtual int adjustMedianCount(int suggestion);
+    virtual bool repeatCount() { return 1; }
+    virtual bool needsWarmupIteration() { return true; }
+    virtual QTest::QBenchmarkMetric metricType();
+
+    static bool isAvailable();
+private:
+};
+
+QT_END_NAMESPACE
+
+#endif // QBENCHMARKPERFEVENTS_P_H

src/testlib/qtestcase.cpp

@@ -1341,6 +1341,9 @@ Q_TESTLIB_EXPORT void qtest_qParseArgs(int argc, char *argv[], bool qml)
 #ifdef QTESTLIB_USE_VALGRIND
          " -callgrind          : Use callgrind to time benchmarks\n"
 #endif
+#ifdef QTESTLIB_USE_PERF_EVENTS
+         " -perf               : Use Linux perf events to time benchmarks\n"
+#endif
 #ifdef HAVE_TICK_COUNTER
          " -tickcounter        : Use CPU tick counters to time benchmarks\n"
 #endif
@@ -1481,6 +1484,14 @@ Q_TESTLIB_EXPORT void qtest_qParseArgs(int argc, char *argv[], bool qml)
             QBenchmarkGlobalData::current->callgrindOutFileBase =
                 QBenchmarkValgrindUtils::outFileBase();
 #endif
+#ifdef QTESTLIB_USE_PERF_EVENTS
+        } else if (strcmp(argv[i], "-perf") == 0) {
+            if (QBenchmarkPerfEventsMeasurer::isAvailable()) {
+                printf("perf available\n");
+            } else {
+                fprintf(stderr, "WARNING: Linux perf events not available. Using the walltime measurer.\n");
+            }
+#endif
 #ifdef HAVE_TICK_COUNTER
         } else if (strcmp(argv[i], "-tickcounter") == 0) {
             QBenchmarkGlobalData::current->setMode(QBenchmarkGlobalData::TickCounter);

src/testlib/testlib.pro

@@ -16,6 +16,7 @@ HEADERS = qbenchmark.h \
     qbenchmarkmeasurement_p.h \
     qbenchmarkvalgrind_p.h \
     qbenchmarkevent_p.h \
+    qbenchmarkperfevents_p.h \
     qbenchmarkmetric_p.h \
     qsignalspy.h \
     qtestaccessible.h \
@@ -48,6 +49,7 @@ SOURCES = qtestcase.cpp \
     qbenchmarkmeasurement.cpp \
     qbenchmarkvalgrind.cpp \
     qbenchmarkevent.cpp \
+    qbenchmarkperfevents.cpp \
     qbenchmarkmetric.cpp \
     qtestelement.cpp \
     qtestelementattribute.cpp \