/*
 * Copyright (c) 2017 ARM Limited.
 *
 * SPDX-License-Identifier: MIT
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#ifndef ARM_COMPUTE_TEST_PMU
#define ARM_COMPUTE_TEST_PMU

#include "arm_compute/core/Error.h"

#include <cstdint>
#include <linux/perf_event.h>
#include <stdexcept>
#include <unistd.h>

namespace arm_compute
{
namespace test
{
namespace framework
{
/** Class provides access to CPU hardware counters. */
class PMU
{
public:
    /** Default constructor. */
    PMU();

    /** Create PMU with specified counter.
     *
     * This constructor automatically calls @ref open with the default
     * configuration.
     *
     * @param[in] config Counter identifier.
     */
    explicit PMU(uint64_t config);

    /** Default destructor. */
    ~PMU();

    /** Get the counter value.
     *
     * @return Counter value casted to the specified type. */
    template <typename T>
    T get_value() const;

    /** Open the specified counter based on the default configuration. */
    void open(uint64_t config);

    /** Open the specified configuration. */
    void open(const perf_event_attr &perf_config);

    /** Close the currently open counter. */
    void close();

    /** Reset counter. */
    void reset();

private:
    perf_event_attr _perf_config;
    long            _fd{ -1 };
};

template <typename T>
T PMU::get_value() const
{
    T             value{};
    const ssize_t result = read(_fd, &value, sizeof(T));

    ARM_COMPUTE_ERROR_ON_MSG(result == -1, "Can't get PMU counter value: %d", errno);
    ARM_COMPUTE_UNUSED(result);

    return value;
}
} // namespace framework
} // namespace test
} // namespace arm_compute
#endif /* ARM_COMPUTE_TEST_PMU */