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      1 /*
      2  * Copyright (C) 2013 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 /*
     18  * Linux task stats reporting tool. Queries and prints out the kernel's
     19  * taskstats structure for a given process or thread group id. See
     20  * https://www.kernel.org/doc/Documentation/accounting/ for more information
     21  * about the reported fields.
     22  */
     23 
     24 #include <errno.h>
     25 #include <getopt.h>
     26 #include <netlink/attr.h>
     27 #include <netlink/genl/genl.h>
     28 #include <netlink/genl/ctrl.h>
     29 #include <netlink/handlers.h>
     30 #include <netlink/msg.h>
     31 #include <stdio.h>
     32 #include <stdlib.h>
     33 #include <sys/cdefs.h>
     34 #include <time.h>
     35 #include <unistd.h>
     36 
     37 #include <linux/taskstats.h>
     38 
     39 struct TaskStatistics {
     40     int pid;
     41     int tgid;
     42     struct taskstats stats;
     43 };
     44 
     45 int print_receive_error(struct sockaddr_nl* address __unused,
     46                         struct nlmsgerr* error, void* arg __unused) {
     47     fprintf(stderr, "Netlink receive error: %s\n", strerror(-error->error));
     48     return NL_STOP;
     49 }
     50 
     51 void parse_aggregate_task_stats(struct nlattr* attr, int attr_size,
     52                                 struct TaskStatistics* stats) {
     53     nla_for_each_attr(attr, attr, attr_size, attr_size) {
     54         switch (attr->nla_type) {
     55             case TASKSTATS_TYPE_PID:
     56                 stats->pid = nla_get_u32(attr);
     57                 break;
     58             case TASKSTATS_TYPE_TGID:
     59                 stats->tgid = nla_get_u32(attr);
     60                 break;
     61             case TASKSTATS_TYPE_STATS:
     62                 nla_memcpy(&stats->stats, attr, sizeof(stats->stats));
     63                 break;
     64             default:
     65                 break;
     66         }
     67     }
     68 }
     69 
     70 int parse_task_stats(struct nl_msg* msg, void* arg) {
     71     struct TaskStatistics* stats = (struct TaskStatistics*)arg;
     72     struct genlmsghdr* gnlh = (struct genlmsghdr*)nlmsg_data(nlmsg_hdr(msg));
     73     struct nlattr* attr = genlmsg_attrdata(gnlh, 0);
     74     int remaining = genlmsg_attrlen(gnlh, 0);
     75 
     76     nla_for_each_attr(attr, attr, remaining, remaining) {
     77         switch (attr->nla_type) {
     78             case TASKSTATS_TYPE_AGGR_PID:
     79             case TASKSTATS_TYPE_AGGR_TGID:
     80                 parse_aggregate_task_stats(nla_data(attr), nla_len(attr),
     81                                            stats);
     82                 break;
     83             default:
     84                 break;
     85         }
     86     }
     87     return NL_STOP;
     88 }
     89 
     90 int query_task_stats(struct nl_sock* netlink_socket, int family_id,
     91                      int command_type, int parameter,
     92                      struct TaskStatistics* stats) {
     93     memset(stats, 0, sizeof(*stats));
     94 
     95     struct nl_msg* message = nlmsg_alloc();
     96     genlmsg_put(message, NL_AUTO_PID, NL_AUTO_SEQ, family_id, 0, 0,
     97 		TASKSTATS_CMD_GET, TASKSTATS_VERSION);
     98     nla_put_u32(message, command_type, parameter);
     99 
    100     int result = nl_send_auto_complete(netlink_socket, message);
    101     nlmsg_free(message);
    102     if (result < 0) {
    103         return result;
    104     }
    105 
    106     struct nl_cb* callbacks = nl_cb_get(nl_cb_alloc(NL_CB_CUSTOM));
    107     nl_cb_set(callbacks, NL_CB_VALID, NL_CB_CUSTOM, &parse_task_stats, stats);
    108     nl_cb_err(callbacks, NL_CB_CUSTOM, &print_receive_error, &family_id);
    109 
    110     result = nl_recvmsgs(netlink_socket, callbacks);
    111     nl_cb_put(callbacks);
    112     if (result < 0) {
    113         return result;
    114     }
    115     return stats->pid || stats->tgid;
    116 }
    117 
    118 double average_ms(unsigned long long total, unsigned long long count) {
    119     if (!count) {
    120         return 0;
    121     }
    122     return ((double)total) / count / 1e6;
    123 }
    124 
    125 unsigned long long average_ns(unsigned long long total,
    126                               unsigned long long count) {
    127     if (!count) {
    128         return 0;
    129     }
    130     return total / count;
    131 }
    132 
    133 void print_task_stats(const struct TaskStatistics* stats,
    134                       int human_readable) {
    135     const struct taskstats* s = &stats->stats;
    136     printf("Basic task statistics\n");
    137     printf("---------------------\n");
    138     printf("%-25s%d\n", "Stats version:", s->version);
    139     printf("%-25s%d\n", "Exit code:", s->ac_exitcode);
    140     printf("%-25s0x%x\n", "Flags:", s->ac_flag);
    141     printf("%-25s%d\n", "Nice value:", s->ac_nice);
    142     printf("%-25s%s\n", "Command name:", s->ac_comm);
    143     printf("%-25s%d\n", "Scheduling discipline:", s->ac_sched);
    144     printf("%-25s%d\n", "UID:", s->ac_uid);
    145     printf("%-25s%d\n", "GID:", s->ac_gid);
    146     printf("%-25s%d\n", "PID:", s->ac_pid);
    147     printf("%-25s%d\n", "PPID:", s->ac_ppid);
    148 
    149     if (human_readable) {
    150         time_t begin_time = s->ac_btime;
    151         printf("%-25s%s", "Begin time:", ctime(&begin_time));
    152     } else {
    153         printf("%-25s%d sec\n", "Begin time:", s->ac_btime);
    154     }
    155     printf("%-25s%llu usec\n", "Elapsed time:", s->ac_etime);
    156     printf("%-25s%llu usec\n", "User CPU time:", s->ac_utime);
    157     printf("%-25s%llu\n", "Minor page faults:", s->ac_minflt);
    158     printf("%-25s%llu\n", "Major page faults:", s->ac_majflt);
    159     printf("%-25s%llu usec\n", "Scaled user time:", s->ac_utimescaled);
    160     printf("%-25s%llu usec\n", "Scaled system time:", s->ac_stimescaled);
    161 
    162     printf("\nDelay accounting\n");
    163     printf("----------------\n");
    164     printf("       %15s%15s%15s%15s%15s%15s\n",
    165            "Count",
    166            human_readable ? "Delay (ms)" : "Delay (ns)",
    167            "Average delay",
    168            "Real delay",
    169            "Scaled real",
    170            "Virtual delay");
    171 
    172     if (!human_readable) {
    173         printf("CPU    %15llu%15llu%15llu%15llu%15llu%15llu\n",
    174                s->cpu_count,
    175                s->cpu_delay_total,
    176                average_ns(s->cpu_delay_total, s->cpu_count),
    177                s->cpu_run_real_total,
    178                s->cpu_scaled_run_real_total,
    179                s->cpu_run_virtual_total);
    180         printf("IO     %15llu%15llu%15llu\n",
    181                s->blkio_count,
    182                s->blkio_delay_total,
    183                average_ns(s->blkio_delay_total, s->blkio_count));
    184         printf("Swap   %15llu%15llu%15llu\n",
    185                s->swapin_count,
    186                s->swapin_delay_total,
    187                average_ns(s->swapin_delay_total, s->swapin_count));
    188         printf("Reclaim%15llu%15llu%15llu\n",
    189                s->freepages_count,
    190                s->freepages_delay_total,
    191                average_ns(s->freepages_delay_total, s->freepages_count));
    192     } else {
    193         const double ms_per_ns = 1e6;
    194         printf("CPU    %15llu%15.3f%15.3f%15.3f%15.3f%15.3f\n",
    195                s->cpu_count,
    196                s->cpu_delay_total / ms_per_ns,
    197                average_ms(s->cpu_delay_total, s->cpu_count),
    198                s->cpu_run_real_total / ms_per_ns,
    199                s->cpu_scaled_run_real_total / ms_per_ns,
    200                s->cpu_run_virtual_total / ms_per_ns);
    201         printf("IO     %15llu%15.3f%15.3f\n",
    202                s->blkio_count,
    203                s->blkio_delay_total / ms_per_ns,
    204                average_ms(s->blkio_delay_total, s->blkio_count));
    205         printf("Swap   %15llu%15.3f%15.3f\n",
    206                s->swapin_count,
    207                s->swapin_delay_total / ms_per_ns,
    208                average_ms(s->swapin_delay_total, s->swapin_count));
    209         printf("Reclaim%15llu%15.3f%15.3f\n",
    210                s->freepages_count,
    211                s->freepages_delay_total / ms_per_ns,
    212                average_ms(s->freepages_delay_total, s->freepages_count));
    213     }
    214 
    215     printf("\nExtended accounting fields\n");
    216     printf("--------------------------\n");
    217     if (human_readable && s->ac_stime) {
    218         printf("%-25s%.3f MB\n", "Average RSS usage:",
    219                (double)s->coremem / s->ac_stime);
    220         printf("%-25s%.3f MB\n", "Average VM usage:",
    221                (double)s->virtmem / s->ac_stime);
    222     } else {
    223         printf("%-25s%llu MB\n", "Accumulated RSS usage:", s->coremem);
    224         printf("%-25s%llu MB\n", "Accumulated VM usage:", s->virtmem);
    225     }
    226     printf("%-25s%llu KB\n", "RSS high water mark:", s->hiwater_rss);
    227     printf("%-25s%llu KB\n", "VM high water mark:", s->hiwater_vm);
    228     printf("%-25s%llu\n", "IO bytes read:", s->read_char);
    229     printf("%-25s%llu\n", "IO bytes written:", s->write_char);
    230     printf("%-25s%llu\n", "IO read syscalls:", s->read_syscalls);
    231     printf("%-25s%llu\n", "IO write syscalls:", s->write_syscalls);
    232 
    233     printf("\nPer-task/thread statistics\n");
    234     printf("--------------------------\n");
    235     printf("%-25s%llu\n", "Voluntary switches:", s->nvcsw);
    236     printf("%-25s%llu\n", "Involuntary switches:", s->nivcsw);
    237 }
    238 
    239 void print_usage() {
    240   printf("Linux task stats reporting tool\n"
    241          "\n"
    242          "Usage: taskstats [options]\n"
    243          "\n"
    244          "Options:\n"
    245          "  --help        This text\n"
    246          "  --pid PID     Print stats for the process id PID\n"
    247          "  --tgid TGID   Print stats for the thread group id TGID\n"
    248          "  --raw         Print raw numbers instead of human readable units\n"
    249          "\n"
    250          "Either PID or TGID must be specified. For more documentation about "
    251          "the reported fields, see\n"
    252          "https://www.kernel.org/doc/Documentation/accounting/"
    253          "taskstats-struct.txt\n");
    254 }
    255 
    256 int main(int argc, char** argv) {
    257     int command_type = 0;
    258     int pid = 0;
    259     int human_readable = 1;
    260 
    261     const struct option long_options[] = {
    262         {"help", no_argument, 0, 0},
    263         {"pid", required_argument, 0, 0},
    264         {"tgid", required_argument, 0, 0},
    265         {"raw", no_argument, 0, 0},
    266         {0, 0, 0, 0}
    267     };
    268 
    269     while (1) {
    270         int option_index;
    271         int option_char = getopt_long_only(argc, argv, "", long_options,
    272                                            &option_index);
    273         if (option_char == -1) {
    274             break;
    275         }
    276         switch (option_index) {
    277             case 0:
    278                 print_usage();
    279                 return EXIT_SUCCESS;
    280             case 1:
    281                 command_type = TASKSTATS_CMD_ATTR_PID;
    282                 pid = atoi(optarg);
    283                 break;
    284             case 2:
    285                 command_type = TASKSTATS_CMD_ATTR_TGID;
    286                 pid = atoi(optarg);
    287                 break;
    288             case 3:
    289                 human_readable = 0;
    290                 break;
    291             default:
    292                 break;
    293         };
    294     }
    295 
    296     if (!pid) {
    297         printf("Either PID or TGID must be specified\n");
    298         return EXIT_FAILURE;
    299     }
    300 
    301     struct nl_sock* netlink_socket = nl_socket_alloc();
    302     if (!netlink_socket) {
    303         fprintf(stderr, "Unable to allocate netlink socket\n");
    304         goto error;
    305     }
    306 
    307     int ret = genl_connect(netlink_socket);
    308     if (ret < 0) {
    309         nl_perror(ret, "Unable to open netlink socket (are you root?)");
    310         goto error;
    311     }
    312 
    313     int family_id = genl_ctrl_resolve(netlink_socket, TASKSTATS_GENL_NAME);
    314     if (family_id < 0) {
    315         nl_perror(family_id, "Unable to determine taskstats family id "
    316                "(does your kernel support taskstats?)");
    317         goto error;
    318     }
    319     struct TaskStatistics stats;
    320     ret = query_task_stats(netlink_socket, family_id, command_type, pid, &stats);
    321     if (ret < 0) {
    322         nl_perror(ret, "Failed to query taskstats");
    323         goto error;
    324     }
    325     print_task_stats(&stats, human_readable);
    326 
    327     nl_socket_free(netlink_socket);
    328     return EXIT_SUCCESS;
    329 
    330 error:
    331     if (netlink_socket) {
    332         nl_socket_free(netlink_socket);
    333     }
    334     return EXIT_FAILURE;
    335 }
    336