/*
* BSD LICENSE
*
* Copyright(c) 2015-2020 Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/syscall.h>
#include <sys/ioctl.h>
#include "types.h"
#include "pqos.h"
#include "perf.h"
#include "log.h"
/**
* @brief Function to request a file descriptor to read perf counters
*
* @param attr perf event attribute structure
* @param pid pid to monitor
* @param cpu cpu to monitor
* @param group_fd fd of group leader (-1 if no leader)
* @param flags perf event flags
*
* @return fd used to read specified perf events
* @retval positive number on success
* @retval negative number on error
*/
static inline int
perf_event_open(struct perf_event_attr *attr,
pid_t pid,
int cpu,
int group_fd,
unsigned long flags)
{
attr->size = sizeof(*attr);
return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags);
}
int
perf_setup_counter(struct perf_event_attr *attr,
const pid_t pid,
const int cpu,
const int group_fd,
const unsigned long flags,
int *counter_fd)
{
int fd;
if (attr == NULL || counter_fd == NULL)
return PQOS_RETVAL_PARAM;
fd = perf_event_open(attr, pid, cpu, group_fd, flags);
if (fd < 0) {
LOG_ERROR("Failed to open perf event!\n");
return PQOS_RETVAL_ERROR;
}
*counter_fd = fd;
return PQOS_RETVAL_OK;
}
int
perf_shutdown_counter(int counter_fd)
{
int ret;
if (counter_fd < 0)
return PQOS_RETVAL_PARAM;
ret = close(counter_fd);
if (ret < 0) {
LOG_ERROR("Failed to shutdown perf counter\n");
return PQOS_RETVAL_ERROR;
}
return PQOS_RETVAL_OK;
}
int
perf_start_counter(int counter_fd)
{
int ret;
if (counter_fd <= 0)
return PQOS_RETVAL_PARAM;
ret = ioctl(counter_fd, PERF_EVENT_IOC_ENABLE);
if (ret < 0) {
LOG_ERROR("Failed to start perf counter!\n");
return PQOS_RETVAL_ERROR;
}
return PQOS_RETVAL_OK;
}
int
perf_stop_counter(int counter_fd)
{
int ret;
if (counter_fd <= 0)
return PQOS_RETVAL_PARAM;
ret = ioctl(counter_fd, PERF_EVENT_IOC_DISABLE);
if (ret < 0) {
LOG_ERROR("Failed to stop perf counter!\n");
return PQOS_RETVAL_ERROR;
}
return PQOS_RETVAL_OK;
}
int
perf_read_counter(int counter_fd, uint64_t *value)
{
size_t res;
if (counter_fd <= 0 || value == NULL)
return PQOS_RETVAL_PARAM;
res = read(counter_fd, value, sizeof(*value));
if (res != sizeof(uint64_t)) {
LOG_ERROR("Failed to read perf counter!\n");
return PQOS_RETVAL_ERROR;
}
return PQOS_RETVAL_OK;
}