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 #if TASKSTATS_VERSION > 8
239     if (s->version > 8) {
240         printf("%-25s%llu\n", "Thrashing count:", s->thrashing_count);
241         printf("%-25s%llu\n", "Thrashing delay total:", s->thrashing_delay_total);
242     }
243 #endif
244 }
245 
246 void print_usage() {
247   printf("Linux task stats reporting tool\n"
248          "\n"
249          "Usage: taskstats [options]\n"
250          "\n"
251          "Options:\n"
252          "  --help        This text\n"
253          "  --pid PID     Print stats for the process id PID\n"
254          "  --tgid TGID   Print stats for the thread group id TGID\n"
255          "  --raw         Print raw numbers instead of human readable units\n"
256          "\n"
257          "Either PID or TGID must be specified. For more documentation about "
258          "the reported fields, see\n"
259          "https://www.kernel.org/doc/Documentation/accounting/"
260          "taskstats-struct.txt\n");
261 }
262 
263 int main(int argc, char** argv) {
264     int command_type = 0;
265     int pid = 0;
266     int human_readable = 1;
267 
268     const struct option long_options[] = {
269         {"help", no_argument, 0, 0},
270         {"pid", required_argument, 0, 0},
271         {"tgid", required_argument, 0, 0},
272         {"raw", no_argument, 0, 0},
273         {0, 0, 0, 0}
274     };
275 
276     while (1) {
277         int option_index;
278         int option_char = getopt_long_only(argc, argv, "", long_options,
279                                            &option_index);
280         if (option_char == -1) {
281             break;
282         }
283         switch (option_index) {
284             case 0:
285                 print_usage();
286                 return EXIT_SUCCESS;
287             case 1:
288                 command_type = TASKSTATS_CMD_ATTR_PID;
289                 pid = atoi(optarg);
290                 break;
291             case 2:
292                 command_type = TASKSTATS_CMD_ATTR_TGID;
293                 pid = atoi(optarg);
294                 break;
295             case 3:
296                 human_readable = 0;
297                 break;
298             default:
299                 break;
300         };
301     }
302 
303     if (!pid) {
304         printf("Either PID or TGID must be specified\n");
305         return EXIT_FAILURE;
306     }
307 
308     struct nl_sock* netlink_socket = nl_socket_alloc();
309     if (!netlink_socket) {
310         fprintf(stderr, "Unable to allocate netlink socket\n");
311         goto error;
312     }
313 
314     int ret = genl_connect(netlink_socket);
315     if (ret < 0) {
316         nl_perror(ret, "Unable to open netlink socket (are you root?)");
317         goto error;
318     }
319 
320     int family_id = genl_ctrl_resolve(netlink_socket, TASKSTATS_GENL_NAME);
321     if (family_id < 0) {
322         nl_perror(family_id, "Unable to determine taskstats family id "
323                "(does your kernel support taskstats?)");
324         goto error;
325     }
326     struct TaskStatistics stats;
327     ret = query_task_stats(netlink_socket, family_id, command_type, pid, &stats);
328     if (ret < 0) {
329         nl_perror(ret, "Failed to query taskstats");
330         goto error;
331     }
332     print_task_stats(&stats, human_readable);
333 
334     nl_socket_free(netlink_socket);
335     return EXIT_SUCCESS;
336 
337 error:
338     if (netlink_socket) {
339         nl_socket_free(netlink_socket);
340     }
341     return EXIT_FAILURE;
342 }
343