agent-enviroments/builder/libs/seastar/tests/perf/linux_perf_event.cc
2024-09-10 17:06:08 +03:00

110 lines
2.9 KiB
C++

/*
* Copyright (C) 2021-present ScyllaDB
*/
/*
* This file is open source software, licensed to you under the terms
* of the Apache License, Version 2.0 (the "License"). See the NOTICE file
* distributed with this work for additional information regarding copyright
* ownership. You may not use this file except in compliance with the License.
*
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
/*
* This file was copied from Scylla (https://github.com/scylladb/scylla)
*/
#include <seastar/testing/linux_perf_event.hh>
#include <linux/perf_event.h>
#include <linux/hw_breakpoint.h>
#include <sys/ioctl.h>
#include <asm/unistd.h>
linux_perf_event::linux_perf_event(const struct ::perf_event_attr& attr, pid_t pid, int cpu, int group_fd, unsigned long flags) {
int ret = syscall(__NR_perf_event_open, &attr, pid, cpu, group_fd, flags);
if (ret != -1) {
_fd = ret; // ignore failures, can happen in constrained environments such as containers
}
}
linux_perf_event::~linux_perf_event() {
if (_fd != -1) {
::close(_fd);
}
}
linux_perf_event&
linux_perf_event::operator=(linux_perf_event&& x) noexcept {
if (this != &x) {
if (_fd != -1) {
::close(_fd);
}
_fd = std::exchange(x._fd, -1);
}
return *this;
}
uint64_t
linux_perf_event::read() {
if (_fd == -1) {
return 0;
}
uint64_t ret;
::read(_fd, &ret, sizeof(ret));
return ret;
}
void
linux_perf_event::enable() {
if (_fd == -1) {
return;
}
::ioctl(_fd, PERF_EVENT_IOC_ENABLE, 0);
}
void
linux_perf_event::disable() {
if (_fd == -1) {
return;
}
::ioctl(_fd, PERF_EVENT_IOC_DISABLE, 0);
}
static linux_perf_event
make_linux_perf_event(unsigned config, pid_t pid = 0, int cpu = -1, int group_fd = -1, unsigned long flags = 0) {
return linux_perf_event(perf_event_attr{
.type = PERF_TYPE_HARDWARE,
.size = sizeof(struct perf_event_attr),
.config = config,
.disabled = 1,
.exclude_kernel = 1,
.exclude_hv = 1,
#if defined(__x86_64__)
// exclude_idle is not supported on all architectures (e.g. aarch64)
// so enable it selectively only on architectures that support it.
.exclude_idle = 1,
#endif
}, pid, cpu, group_fd, flags);
}
linux_perf_event
linux_perf_event::user_instructions_retired() {
return make_linux_perf_event(PERF_COUNT_HW_INSTRUCTIONS);
}
linux_perf_event
linux_perf_event::user_cpu_cycles_retired() {
return make_linux_perf_event(PERF_COUNT_HW_CPU_CYCLES);
}