aosp12/system/extras/iotop/taskstats.cpp

239 lines
7.5 KiB
C++

// Copyright (C) 2015 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// 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.
#include <linux/taskstats.h>
#include <netlink/genl/ctrl.h>
#include <netlink/genl/genl.h>
#include <netlink/socket.h>
#include <algorithm>
#include <memory>
#include <android-base/logging.h>
#include "taskstats.h"
TaskstatsSocket::TaskstatsSocket() : nl_(nullptr, nl_socket_free), family_id_(0) {}
bool TaskstatsSocket::Open() {
std::unique_ptr<nl_sock, decltype(&nl_socket_free)> nl(nl_socket_alloc(), nl_socket_free);
if (!nl.get()) {
LOG(ERROR) << "Failed to allocate netlink socket";
return false;
}
int ret = genl_connect(nl.get());
if (ret < 0) {
LOG(ERROR) << nl_geterror(ret) << std::endl << "Unable to open netlink socket (are you root?)";
return false;
}
int family_id = genl_ctrl_resolve(nl.get(), TASKSTATS_GENL_NAME);
if (family_id < 0) {
LOG(ERROR) << nl_geterror(family_id) << std::endl
<< "Unable to determine taskstats family id (does your kernel support taskstats?)";
return false;
}
nl_ = std::move(nl);
family_id_ = family_id;
return true;
}
void TaskstatsSocket::Close() {
nl_.reset();
}
struct TaskStatsRequest {
pid_t requested_pid;
taskstats stats;
};
static pid_t ParseAggregateTaskStats(nlattr* attr, int attr_size, taskstats* stats) {
pid_t received_pid = -1;
nla_for_each_attr(attr, attr, attr_size, attr_size) {
switch (nla_type(attr)) {
case TASKSTATS_TYPE_PID:
case TASKSTATS_TYPE_TGID:
received_pid = nla_get_u32(attr);
break;
case TASKSTATS_TYPE_STATS: {
int len = static_cast<int>(sizeof(*stats));
len = std::min(len, nla_len(attr));
nla_memcpy(stats, attr, len);
return received_pid;
}
default:
LOG(ERROR) << "unexpected attribute inside AGGR";
return -1;
}
}
return -1;
}
static int ParseTaskStats(nl_msg* msg, void* arg) {
TaskStatsRequest* taskstats_request = static_cast<TaskStatsRequest*>(arg);
genlmsghdr* gnlh = static_cast<genlmsghdr*>(nlmsg_data(nlmsg_hdr(msg)));
nlattr* attr = genlmsg_attrdata(gnlh, 0);
int remaining = genlmsg_attrlen(gnlh, 0);
nla_for_each_attr(attr, attr, remaining, remaining) {
switch (nla_type(attr)) {
case TASKSTATS_TYPE_AGGR_PID:
case TASKSTATS_TYPE_AGGR_TGID: {
nlattr* nested_attr = static_cast<nlattr*>(nla_data(attr));
taskstats stats;
pid_t ret;
ret = ParseAggregateTaskStats(nested_attr, nla_len(attr), &stats);
if (ret < 0) {
LOG(ERROR) << "Bad AGGR_PID contents";
} else if (ret == taskstats_request->requested_pid) {
taskstats_request->stats = stats;
} else {
LOG(WARNING) << "got taskstats for unexpected pid " << ret << " (expected "
<< taskstats_request->requested_pid << ", continuing...";
}
break;
}
case TASKSTATS_TYPE_NULL:
break;
default:
LOG(ERROR) << "unexpected attribute in taskstats";
}
}
return NL_OK;
}
bool TaskstatsSocket::GetStats(int pid, int type, TaskStatistics& stats) {
TaskStatsRequest taskstats_request = TaskStatsRequest();
taskstats_request.requested_pid = pid;
std::unique_ptr<nl_msg, decltype(&nlmsg_free)> message(nlmsg_alloc(), nlmsg_free);
genlmsg_put(message.get(), NL_AUTO_PID, NL_AUTO_SEQ, family_id_, 0, 0, TASKSTATS_CMD_GET,
TASKSTATS_VERSION);
nla_put_u32(message.get(), type, pid);
int result = nl_send_auto_complete(nl_.get(), message.get());
if (result < 0) {
return false;
}
std::unique_ptr<nl_cb, decltype(&nl_cb_put)> callbacks(nl_cb_alloc(NL_CB_DEFAULT), nl_cb_put);
nl_cb_set(callbacks.get(), NL_CB_VALID, NL_CB_CUSTOM, &ParseTaskStats,
static_cast<void*>(&taskstats_request));
result = nl_recvmsgs(nl_.get(), callbacks.get());
if (result < 0) {
return false;
}
nl_wait_for_ack(nl_.get());
stats = TaskStatistics(taskstats_request.stats);
return true;
}
bool TaskstatsSocket::GetPidStats(int pid, TaskStatistics& stats) {
return GetStats(pid, TASKSTATS_CMD_ATTR_PID, stats);
}
bool TaskstatsSocket::GetTgidStats(int tgid, TaskStatistics& stats) {
bool ret = GetStats(tgid, TASKSTATS_CMD_ATTR_TGID, stats);
if (ret) {
stats.set_pid(tgid);
}
return ret;
}
TaskStatistics::TaskStatistics(const taskstats& taskstats_stats) {
comm_ = std::string(taskstats_stats.ac_comm);
pid_ = taskstats_stats.ac_pid;
uid_ = taskstats_stats.ac_uid;
gid_ = taskstats_stats.ac_gid;
pid_ = taskstats_stats.ac_pid;
ppid_ = taskstats_stats.ac_ppid;
cpu_delay_count_ = taskstats_stats.cpu_count;
cpu_delay_ns_ = taskstats_stats.cpu_delay_total;
block_io_delay_count_ = taskstats_stats.blkio_count;
block_io_delay_ns_ = taskstats_stats.blkio_delay_total;
swap_in_delay_count_ = taskstats_stats.swapin_count;
swap_in_delay_ns_ = taskstats_stats.swapin_delay_total;
reclaim_delay_count_ = taskstats_stats.freepages_count;
reclaim_delay_ns_ = taskstats_stats.freepages_delay_total;
total_delay_ns_ = cpu_delay_ns_ + block_io_delay_ns_ + swap_in_delay_ns_ + reclaim_delay_ns_;
cpu_time_real_ = taskstats_stats.cpu_run_real_total;
cpu_time_virtual_ = taskstats_stats.cpu_run_virtual_total;
majflt_ = taskstats_stats.ac_majflt;
minflt_ = taskstats_stats.ac_minflt;
read_bytes_ = taskstats_stats.read_bytes;
write_bytes_ = taskstats_stats.write_bytes;
read_write_bytes_ = read_bytes_ + write_bytes_;
cancelled_write_bytes_ = taskstats_stats.cancelled_write_bytes;
threads_ = 1;
}
void TaskStatistics::AddPidToTgid(const TaskStatistics& pid_statistics) {
// tgid statistics already contain delay values totalled across all pids
// only add IO statistics
read_bytes_ += pid_statistics.read_bytes_;
write_bytes_ += pid_statistics.write_bytes_;
read_write_bytes_ += pid_statistics.read_write_bytes_;
cancelled_write_bytes_ += pid_statistics.cancelled_write_bytes_;
if (pid_ == pid_statistics.pid_) {
comm_ = pid_statistics.comm_;
uid_ = pid_statistics.uid_;
gid_ = pid_statistics.pid_;
ppid_ = pid_statistics.ppid_;
} else {
threads_++;
}
}
// Store new statistics and return the delta from the old statistics
TaskStatistics TaskStatistics::Update(const TaskStatistics& new_statistics) {
TaskStatistics delta = new_statistics;
delta.minflt_ -= minflt_;
delta.majflt_ -= majflt_;
delta.cpu_delay_count_ -= cpu_delay_count_;
delta.cpu_delay_ns_ -= cpu_delay_ns_;
delta.block_io_delay_count_ -= block_io_delay_count_;
delta.block_io_delay_ns_ -= block_io_delay_ns_;
delta.swap_in_delay_count_ -= swap_in_delay_count_;
delta.swap_in_delay_ns_ -= swap_in_delay_ns_;
delta.reclaim_delay_count_ -= reclaim_delay_count_;
delta.reclaim_delay_ns_ -= reclaim_delay_ns_;
delta.total_delay_ns_ -= total_delay_ns_;
delta.cpu_time_real_ -= cpu_time_real_;
delta.cpu_time_virtual_ -= cpu_time_virtual_;
delta.read_bytes_ -= read_bytes_;
delta.write_bytes_ -= write_bytes_;
delta.read_write_bytes_ -= read_write_bytes_;
delta.cancelled_write_bytes_ -= cancelled_write_bytes_;
*this = new_statistics;
return delta;
}