/* 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. 2005 * Copyright (C) Balbir Singh, IBM Corp. 2006 * Copyright (c) Jay Lan, SGI. 2006 * * 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/types.h> #include <signal.h> #include <linux/genetlink.h> #include <linux/taskstats.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; __u64 stime, utime; #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 /* Maximum length of pathname to log file */ #define MAX_FILENAME 256 struct msgtemplate { struct nlmsghdr n; struct genlmsghdr g; char buf[MAX_MSG_SIZE]; }; char cpumask[100+6*MAX_CPUS]; /* * 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) { fprintf(stderr, "Unable to set socket rcv buf size " "to %d\n", rcvbufsz); return -1; } memset(&local, 0, sizeof(local)); local.nl_family = AF_NETLINK; if (bind(fd, (struct sockaddr *) &local, sizeof(local)) < 0) goto error; return fd; error: close(fd); return -1; } 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 + 1 + NLA_HDRLEN; memcpy(NLA_DATA(na), nla_data, nla_len); msg.n.nlmsg_len += NLMSG_ALIGN(na->nla_len); buf = (char *) &msg; buflen = msg.n.nlmsg_len ; memset(&nladdr, 0, sizeof(nladdr)); 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 */ int get_family_id(int sd) { struct { struct nlmsghdr n; struct genlmsghdr g; char buf[256]; } ans; int id, rc; struct nlattr *na; int rep_len; strcpy(name, TASKSTATS_GENL_NAME); rc = send_cmd(sd, GENL_ID_CTRL, getpid(), CTRL_CMD_GETFAMILY, CTRL_ATTR_FAMILY_NAME, (void *)name, strlen(TASKSTATS_GENL_NAME)+1); 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; } void print_delayacct(struct taskstats *t) { printf("\n\nCPU %15s%15s%15s%15s\n" " %15llu%15llu%15llu%15llu\n" "IO %15s%15s\n" " %15llu%15llu\n" "MEM %15s%15s\n" " %15llu%15llu\n\n", "count", "real total", "virtual total", "delay total", t->cpu_count, t->cpu_run_real_total, t->cpu_run_virtual_total, t->cpu_delay_total, "count", "delay total", t->blkio_count, t->blkio_delay_total, "count", "delay total", t->swapin_count, t->swapin_delay_total); } void print_ioacct(struct taskstats *t) { printf("%s: read=%llu, write=%llu, cancelled_write=%llu\n", 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, cmd_type; __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[128]; int loop = 0; struct msgtemplate msg; while (1) { c = getopt(argc, argv, "diw:r:m:t:p:v:l"); if (c < 0) break; switch (c) { case 'd': printf("print delayacct stats ON\n"); print_delays = 1; break; case 'i': printf("printing IO accounting\n"); print_io_accounting = 1; break; case 'w': strncpy(logfile, optarg, MAX_FILENAME); printf("write to file %s\n", logfile); write_file = 1; break; case 'r': rcvbufsz = atoi(optarg); printf("receive buf size %d\n", rcvbufsz); if (rcvbufsz < 0) err(1, "Invalid rcv buf size\n"); break; case 'm': strncpy(cpumask, optarg, sizeof(cpumask)); maskset = 1; printf("cpumask %s maskset %d\n", cpumask, maskset); break; case 't': tid = atoi(optarg); if (!tid) err(1, "Invalid tgid\n"); cmd_type = TASKSTATS_CMD_ATTR_TGID; break; case 'p': tid = atoi(optarg); if (!tid) err(1, "Invalid pid\n"); cmd_type = TASKSTATS_CMD_ATTR_PID; break; case 'v': printf("debug on\n"); dbg = 1; break; case 'l': printf("listen forever\n"); loop = 1; break; default: printf("Unknown option %d\n", c); exit(-1); } } if (write_file) { fd = open(logfile, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); if (fd == -1) { perror("Cannot open output file\n"); exit(1); } } if ((nl_sd = create_nl_socket(NETLINK_GENERIC)) < 0) err(1, "error creating Netlink socket\n"); mypid = getpid(); id = get_family_id(nl_sd); if (!id) { fprintf(stderr, "Error getting family id, errno %d\n", errno); 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, &cpumask, strlen(cpumask) + 1); PRINTF("Sent register cpumask, retval %d\n", rc); if (rc < 0) { fprintf(stderr, "error sending register cpumask\n"); goto err; } } 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) { fprintf(stderr, "error sending tid/tgid cmd\n"); goto done; } } do { int i; rep_len = recv(nl_sd, &msg, sizeof(msg), 0); PRINTF("received %d bytes\n", rep_len); if (rep_len < 0) { fprintf(stderr, "nonfatal reply error: errno %d\n", errno); continue; } if (msg.n.nlmsg_type == NLMSG_ERROR || !NLMSG_OK((&msg.n), rep_len)) { struct nlmsgerr *err = NLMSG_DATA(&msg); fprintf(stderr, "fatal reply error, errno %d\n", err->error); goto done; } PRINTF("nlmsghdr size=%d, 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; i = 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) printf("PID\t%d\n", rtid); break; case TASKSTATS_TYPE_TGID: rtid = *(int *) NLA_DATA(na); if (print_delays) printf("TGID\t%d\n", rtid); 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 (fd) { if (write(fd, NLA_DATA(na), na->nla_len) < 0) { err(1,"write error\n"); } } if (!loop) goto done; break; default: fprintf(stderr, "Unknown nested" " nla_type %d\n", na->nla_type); break; } len2 += NLA_ALIGN(na->nla_len); na = (struct nlattr *) ((char *) na + len2); } break; default: fprintf(stderr, "Unknown nla_type %d\n", na->nla_type); 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, &cpumask, strlen(cpumask) + 1); printf("Sent deregister mask, retval %d\n", rc); if (rc < 0) err(rc, "error sending deregister cpumask\n"); } err: close(nl_sd); if (fd) close(fd); return 0; }