- // SPDX-License-Identifier: GPL-2.0
- /* getdelays.c
- *
- * Utility to get per-pid and per-tgid delay accounting statistics
- * Also illustrates usage of the taskstats interface
- *
- * Copyright (C) Shailabh Nagar, IBM Corp.
- * Copyright (C) Balbir Singh, IBM Corp.
- * Copyright (c) Jay Lan, SGI.
- *
- * Compile with
- * gcc -I/usr/src/linux/include getdelays.c -o getdelays
- */
- #include <stdio.h>
- #include <stdlib.h>
- #include <errno.h>
- #include <unistd.h>
- #include <poll.h>
- #include <string.h>
- #include <fcntl.h>
- #include <sys/types.h>
- #include <sys/stat.h>
- #include <sys/socket.h>
- #include <sys/wait.h>
- #include <signal.h>
- #include <linux/genetlink.h>
- #include <linux/taskstats.h>
- #include <linux/cgroupstats.h>
- /*
- * Generic macros for dealing with netlink sockets. Might be duplicated
- * elsewhere. It is recommended that commercial grade applications use
- * libnl or libnetlink and use the interfaces provided by the library
- */
- #define GENLMSG_DATA(glh) ((void *)(NLMSG_DATA(glh) + GENL_HDRLEN))
- #define GENLMSG_PAYLOAD(glh) (NLMSG_PAYLOAD(glh, 0) - GENL_HDRLEN)
- #define NLA_DATA(na) ((void *)((char*)(na) + NLA_HDRLEN))
- #define NLA_PAYLOAD(len) (len - NLA_HDRLEN)
- #define err(code, fmt, arg...) \
- do { \
- fprintf(stderr, fmt, ##arg); \
- exit(code); \
- } while (0)
- int done;
- int rcvbufsz;
- char name[100];
- int dbg;
- int print_delays;
- int print_io_accounting;
- int print_task_context_switch_counts;
- #define PRINTF(fmt, arg...) { \
- if (dbg) { \
- printf(fmt, ##arg); \
- } \
- }
- /* Maximum size of response requested or message sent */
- #define MAX_MSG_SIZE 1024
- /* Maximum number of cpus expected to be specified in a cpumask */
- #define MAX_CPUS 32
- struct msgtemplate {
- struct nlmsghdr n;
- struct genlmsghdr g;
- char buf[MAX_MSG_SIZE];
- };
- char cpumask[100+6*MAX_CPUS];
- static void usage(void)
- {
- "[-m cpumask] [-t tgid] [-p pid]\n");
- }
- /*
- * Create a raw netlink socket and bind
- */
- static int create_nl_socket(int protocol)
- {
- int fd;
- struct sockaddr_nl local;
- fd = socket(AF_NETLINK, SOCK_RAW, protocol);
- if (fd < 0)
- return -1;
- if (rcvbufsz)
- if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
- &rcvbufsz, sizeof(rcvbufsz)) < 0) {
- rcvbufsz);
- goto error;
- }
- local.nl_family = AF_NETLINK;
- if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0)
- goto error;
- return fd;
- error:
- close(fd);
- return -1;
- }
- static int send_cmd(int sd, __u16 nlmsg_type, __u32 nlmsg_pid,
- __u8 genl_cmd, __u16 nla_type,
- void *nla_data, int nla_len)
- {
- struct nlattr *na;
- struct sockaddr_nl nladdr;
- int r, buflen;
- char *buf;
- struct msgtemplate msg;
- msg.n.nlmsg_len = NLMSG_LENGTH(GENL_HDRLEN);
- msg.n.nlmsg_type = nlmsg_type;
- msg.n.nlmsg_flags = NLM_F_REQUEST;
- msg.n.nlmsg_seq = 0;
- msg.n.nlmsg_pid = nlmsg_pid;
- msg.g.cmd = genl_cmd;
- msg.g.version = 0x1;
- na = (struct nlattr *) GENLMSG_DATA(&msg);
- na->nla_type = nla_type;
- na->nla_len = nla_len + NLA_HDRLEN;
- msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len);
- buf = (char *) &msg;
- buflen = msg.n.nlmsg_len ;
- nladdr.nl_family = AF_NETLINK;
- while ((r = sendto(sd, buf, buflen, 0, (struct sockaddr *) &nladdr,
- sizeof(nladdr))) < buflen) {
- if (r > 0) {
- buf += r;
- buflen -= r;
- } else if (errno != EAGAIN)
- return -1;
- }
- return 0;
- }
- /*
- * Probe the controller in genetlink to find the family id
- * for the TASKSTATS family
- */
- static int get_family_id(int sd)
- {
- struct {
- struct nlmsghdr n;
- struct genlmsghdr g;
- char buf[256];
- } ans;
- int id = 0, rc;
- struct nlattr *na;
- int rep_len;
- rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY,
- CTRL_ATTR_FAMILY_NAME, (void *)name,
- if (rc < 0)
- return 0; /* sendto() failure? */
- rep_len = recv(sd, &ans, sizeof(ans), 0);
- if (ans.n.nlmsg_type == NLMSG_ERROR ||
- (rep_len < 0) || !NLMSG_OK((&ans.n), rep_len))
- return 0;
- na = (struct nlattr *) GENLMSG_DATA(&ans);
- na = (struct nlattr *) ((char *) na + NLA_ALIGN(na->nla_len));
- if (na->nla_type == CTRL_ATTR_FAMILY_ID) {
- id = *(__u16 *) NLA_DATA(na);
- }
- return id;
- }
- #define average_ms(t, c) (t / 1000000ULL / (c ? c : 1))
- static void print_delayacct(struct taskstats *t)
- {
- " %15llu%15llu%15llu%15llu%15.3fms\n"
- "IO %15s%15s%15s\n"
- " %15llu%15llu%15llums\n"
- "SWAP %15s%15s%15s\n"
- " %15llu%15llu%15llums\n"
- "RECLAIM %12s%15s%15s\n"
- " %15llu%15llu%15llums\n"
- "THRASHING%12s%15s%15s\n"
- " %15llu%15llu%15llums\n",
- "count", "real total", "virtual total",
- "delay total", "delay average",
- (unsigned long long)t->cpu_count,
- (unsigned long long)t->cpu_run_real_total,
- (unsigned long long)t->cpu_run_virtual_total,
- (unsigned long long)t->cpu_delay_total,
- average_ms((double)t->cpu_delay_total, t->cpu_count),
- "count", "delay total", "delay average",
- (unsigned long long)t->blkio_count,
- (unsigned long long)t->blkio_delay_total,
- average_ms(t->blkio_delay_total, t->blkio_count),
- "count", "delay total", "delay average",
- (unsigned long long)t->swapin_count,
- (unsigned long long)t->swapin_delay_total,
- average_ms(t->swapin_delay_total, t->swapin_count),
- "count", "delay total", "delay average",
- (unsigned long long)t->freepages_count,
- (unsigned long long)t->freepages_delay_total,
- average_ms(t->freepages_delay_total, t->freepages_count),
- "count", "delay total", "delay average",
- (unsigned long long)t->thrashing_count,
- (unsigned long long)t->thrashing_delay_total,
- average_ms(t->thrashing_delay_total, t->thrashing_count));
- }
- static void task_context_switch_counts(struct taskstats *t)
- {
- " %15llu%15llu\n",
- "voluntary", "nonvoluntary",
- (unsigned long long)t->nvcsw, (unsigned long long)t->nivcsw);
- }
- static void print_cgroupstats(struct cgroupstats *c)
- {
- "uninterruptible %llu\n", (unsigned long long)c->nr_sleeping,
- (unsigned long long)c->nr_io_wait,
- (unsigned long long)c->nr_running,
- (unsigned long long)c->nr_stopped,
- (unsigned long long)c->nr_uninterruptible);
- }
- static void print_ioacct(struct taskstats *t)
- {
- t->ac_comm,
- (unsigned long long)t->read_bytes,
- (unsigned long long)t->write_bytes,
- (unsigned long long)t->cancelled_write_bytes);
- }
- int main(int argc, char *argv[])
- {
- int c, rc, rep_len, aggr_len, len2;
- int cmd_type = TASKSTATS_CMD_ATTR_UNSPEC;
- __u16 id;
- __u32 mypid;
- struct nlattr *na;
- int nl_sd = -1;
- int len = 0;
- pid_t tid = 0;
- pid_t rtid = 0;
- int fd = 0;
- int count = 0;
- int write_file = 0;
- int maskset = 0;
- char *logfile = NULL;
- int loop = 0;
- int containerset = 0;
- char *containerpath = NULL;
- int cfd = 0;
- int forking = 0;
- sigset_t sigset;
- struct msgtemplate msg;
- while (!forking) {
- c = getopt(argc, argv, "qdiw:r:m:t:p:vlC:c:");
- if (c < 0)
- break;
- switch (c) {
- case 'd':
- print_delays = 1;
- break;
- case 'i':
- print_io_accounting = 1;
- break;
- case 'q':
- print_task_context_switch_counts = 1;
- break;
- case 'C':
- containerset = 1;
- containerpath = optarg;
- break;
- case 'w':
- logfile = strdup(optarg);
- write_file = 1;
- break;
- case 'r':
- if (rcvbufsz < 0)
- err(1, "Invalid rcv buf size\n");
- break;
- case 'm':
- cpumask[sizeof(cpumask) - 1] = '\0';
- maskset = 1;
- break;
- case 't':
- if (!tid)
- err(1, "Invalid tgid\n");
- cmd_type = TASKSTATS_CMD_ATTR_TGID;
- break;
- case 'p':
- if (!tid)
- err(1, "Invalid pid\n");
- cmd_type = TASKSTATS_CMD_ATTR_PID;
- break;
- case 'c':
- /* Block SIGCHLD for sigwait() later */
- if (sigemptyset(&sigset) == -1)
- err(1, "Failed to empty sigset");
- if (sigaddset(&sigset, SIGCHLD))
- err(1, "Failed to set sigchld in sigset");
- sigprocmask(SIG_BLOCK, &sigset, NULL);
- /* fork/exec a child */
- tid = fork();
- if (tid < 0)
- err(1, "Fork failed\n");
- if (tid == 0)
- if (execvp(argv[optind - 1],
- &argv[optind - 1]) < 0)
- /* Set the command type and avoid further processing */
- cmd_type = TASKSTATS_CMD_ATTR_PID;
- forking = 1;
- break;
- case 'v':
- dbg = 1;
- break;
- case 'l':
- loop = 1;
- break;
- default:
- usage();
- }
- }
- if (write_file) {
- fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC,
- S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
- if (fd == -1) {
- }
- }
- nl_sd = create_nl_socket(NETLINK_GENERIC);
- if (nl_sd < 0)
- err(1, "error creating Netlink socket\n");
- mypid = getpid();
- id = get_family_id(nl_sd);
- if (!id) {
- goto err;
- }
- PRINTF("family id %d\n", id);
- if (maskset) {
- rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
- TASKSTATS_CMD_ATTR_REGISTER_CPUMASK,
- PRINTF("Sent register cpumask, retval %d\n", rc);
- if (rc < 0) {
- goto err;
- }
- }
- if (tid && containerset) {
- goto err;
- }
- /*
- * If we forked a child, wait for it to exit. Cannot use waitpid()
- * as all the delicious data would be reaped as part of the wait
- */
- if (tid && forking) {
- int sig_received;
- sigwait(&sigset, &sig_received);
- }
- if (tid) {
- rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
- cmd_type, &tid, sizeof(__u32));
- PRINTF("Sent pid/tgid, retval %d\n", rc);
- if (rc < 0) {
- goto done;
- }
- }
- if (containerset) {
- cfd = open(containerpath, O_RDONLY);
- if (cfd < 0) {
- goto err;
- }
- rc = send_cmd(nl_sd, id, mypid, CGROUPSTATS_CMD_GET,
- CGROUPSTATS_CMD_ATTR_FD, &cfd, sizeof(__u32));
- if (rc < 0) {
- goto err;
- }
- }
- if (!maskset && !tid && !containerset) {
- usage();
- goto err;
- }
- do {
- rep_len = recv(nl_sd, &msg, sizeof(msg), 0);
- PRINTF("received %d bytes\n", rep_len);
- if (rep_len < 0) {
- errno);
- continue;
- }
- if (msg.n.nlmsg_type == NLMSG_ERROR ||
- !NLMSG_OK((&msg.n), rep_len)) {
- struct nlmsgerr *err = NLMSG_DATA(&msg);
- err->error);
- goto done;
- }
- PRINTF("nlmsghdr size=%zu, nlmsg_len=%d, rep_len=%d\n",
- sizeof(struct nlmsghdr), msg.n.nlmsg_len, rep_len);
- rep_len = GENLMSG_PAYLOAD(&msg.n);
- na = (struct nlattr *) GENLMSG_DATA(&msg);
- len = 0;
- while (len < rep_len) {
- len += NLA_ALIGN(na->nla_len);
- switch (na->nla_type) {
- case TASKSTATS_TYPE_AGGR_TGID:
- /* Fall through */
- case TASKSTATS_TYPE_AGGR_PID:
- aggr_len = NLA_PAYLOAD(na->nla_len);
- len2 = 0;
- /* For nested attributes, na follows */
- na = (struct nlattr *) NLA_DATA(na);
- done = 0;
- while (len2 < aggr_len) {
- switch (na->nla_type) {
- case TASKSTATS_TYPE_PID:
- rtid = *(int *) NLA_DATA(na);
- if (print_delays)
- break;
- case TASKSTATS_TYPE_TGID:
- rtid = *(int *) NLA_DATA(na);
- if (print_delays)
- break;
- case TASKSTATS_TYPE_STATS:
- count++;
- if (print_delays)
- print_delayacct((struct taskstats *) NLA_DATA(na));
- if (print_io_accounting)
- print_ioacct((struct taskstats *) NLA_DATA(na));
- if (print_task_context_switch_counts)
- task_context_switch_counts((struct taskstats *) NLA_DATA(na));
- if (fd) {
- if (write(fd, NLA_DATA(na), na->nla_len) < 0) {
- err(1,"write error\n");
- }
- }
- if (!loop)
- goto done;
- break;
- case TASKSTATS_TYPE_NULL:
- break;
- default:
- " nla_type %d\n",
- na->nla_type);
- break;
- }
- len2 += NLA_ALIGN(na->nla_len);
- na = (struct nlattr *)((char *)na +
- NLA_ALIGN(na->nla_len));
- }
- break;
- case CGROUPSTATS_TYPE_CGROUP_STATS:
- print_cgroupstats(NLA_DATA(na));
- break;
- default:
- na->nla_type);
- case TASKSTATS_TYPE_NULL:
- break;
- }
- na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);
- }
- } while (loop);
- done:
- if (maskset) {
- rc = send_cmd(nl_sd, id, mypid, TASKSTATS_CMD_GET,
- TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK,
- if (rc < 0)
- err(rc, "error sending deregister cpumask\n");
- }
- err:
- close(nl_sd);
- if (fd)
- close(fd);
- if (cfd)
- close(cfd);
- return 0;
- }
Raw Paste