+++ /dev/null
-/* lttd
- *
- * Linux Trace Toolkit Daemon
- *
- * This is a simple daemon that reads a few relay+debugfs channels and save
- * them in a trace.
- *
- *
- * Copyright 2005 -
- * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
- */
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
-#define _REENTRANT
-#define _GNU_SOURCE
-#include <features.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <stdlib.h>
-#include <dirent.h>
-#include <string.h>
-#include <fcntl.h>
-#include <sys/poll.h>
-#include <sys/mman.h>
-#include <signal.h>
-#include <pthread.h>
-
-/* Relayfs IOCTL */
-#include <asm/ioctl.h>
-#include <asm/types.h>
-
-/* Get the next sub buffer that can be read. */
-#define RELAY_GET_SUBBUF _IOR(0xF4, 0x00,__u32)
-/* Release the oldest reserved (by "get") sub buffer. */
-#define RELAY_PUT_SUBBUF _IOW(0xF4, 0x01,__u32)
-/* returns the number of sub buffers in the per cpu channel. */
-#define RELAY_GET_N_SUBBUFS _IOR(0xF4, 0x02,__u32)
-/* returns the size of the sub buffers. */
-#define RELAY_GET_SUBBUF_SIZE _IOR(0xF4, 0x03,__u32)
-
-
-
-enum {
- GET_SUBBUF,
- PUT_SUBBUF,
- GET_N_BUBBUFS,
- GET_SUBBUF_SIZE
-};
-
-struct fd_pair {
- int channel;
- int trace;
- unsigned int n_subbufs;
- unsigned int subbuf_size;
- void *mmap;
- pthread_mutex_t mutex;
-};
-
-struct channel_trace_fd {
- struct fd_pair *pair;
- int num_pairs;
-};
-
-static char *trace_name = NULL;
-static char *channel_name = NULL;
-static int daemon_mode = 0;
-static int append_mode = 0;
-static unsigned long num_threads = 1;
-volatile static int quit_program = 0; /* For signal handler */
-static int dump_flight_only = 0;
-static int dump_normal_only = 0;
-
-/* Args :
- *
- * -t directory Directory name of the trace to write to. Will be created.
- * -c directory Root directory of the debugfs trace channels.
- * -d Run in background (daemon).
- * -a Trace append mode.
- * -s Send SIGUSR1 to parent when ready for IO.
- */
-void show_arguments(void)
-{
- printf("Please use the following arguments :\n");
- printf("\n");
- printf("-t directory Directory name of the trace to write to.\n"
- " It will be created.\n");
- printf("-c directory Root directory of the debugfs trace channels.\n");
- printf("-d Run in background (daemon).\n");
- printf("-a Append to an possibly existing trace.\n");
- printf("-N Number of threads to start.\n");
- printf("-f Dump only flight recorder channels.\n");
- printf("-n Dump only normal channels.\n");
- printf("\n");
-}
-
-
-/* parse_arguments
- *
- * Parses the command line arguments.
- *
- * Returns 1 if the arguments were correct, but doesn't ask for program
- * continuation. Returns -1 if the arguments are incorrect, or 0 if OK.
- */
-int parse_arguments(int argc, char **argv)
-{
- int ret = 0;
- int argn = 1;
-
- if(argc == 2) {
- if(strcmp(argv[1], "-h") == 0) {
- return 1;
- }
- }
-
- while(argn < argc) {
-
- switch(argv[argn][0]) {
- case '-':
- switch(argv[argn][1]) {
- case 't':
- if(argn+1 < argc) {
- trace_name = argv[argn+1];
- argn++;
- }
- break;
- case 'c':
- if(argn+1 < argc) {
- channel_name = argv[argn+1];
- argn++;
- }
- break;
- case 'd':
- daemon_mode = 1;
- break;
- case 'a':
- append_mode = 1;
- break;
- case 'N':
- if(argn+1 < argc) {
- num_threads = strtoul(argv[argn+1], NULL, 0);
- argn++;
- }
- break;
- case 'f':
- dump_flight_only = 1;
- break;
- case 'n':
- dump_normal_only = 1;
- break;
- default:
- printf("Invalid argument '%s'.\n", argv[argn]);
- printf("\n");
- ret = -1;
- }
- break;
- default:
- printf("Invalid argument '%s'.\n", argv[argn]);
- printf("\n");
- ret = -1;
- }
- argn++;
- }
-
- if(trace_name == NULL) {
- printf("Please specify a trace name.\n");
- printf("\n");
- ret = -1;
- }
-
- if(channel_name == NULL) {
- printf("Please specify a channel name.\n");
- printf("\n");
- ret = -1;
- }
-
- return ret;
-}
-
-void show_info(void)
-{
- printf("Linux Trace Toolkit Trace Daemon\n");
- printf("\n");
- printf("Reading from debugfs directory : %s\n", channel_name);
- printf("Writing to trace directory : %s\n", trace_name);
- printf("\n");
-}
-
-
-/* signal handling */
-
-static void handler(int signo)
-{
- printf("Signal %d received : exiting cleanly\n", signo);
- quit_program = 1;
-}
-
-
-
-int open_channel_trace_pairs(char *subchannel_name, char *subtrace_name,
- struct channel_trace_fd *fd_pairs)
-{
- DIR *channel_dir = opendir(subchannel_name);
- struct dirent *entry;
- struct stat stat_buf;
- int ret;
- char path_channel[PATH_MAX];
- int path_channel_len;
- char *path_channel_ptr;
- char path_trace[PATH_MAX];
- int path_trace_len;
- char *path_trace_ptr;
- int open_ret = 0;
-
- if(channel_dir == NULL) {
- perror(subchannel_name);
- open_ret = ENOENT;
- goto end;
- }
-
- printf("Creating trace subdirectory %s\n", subtrace_name);
- ret = mkdir(subtrace_name, S_IRWXU|S_IRWXG|S_IRWXO);
- if(ret == -1) {
- if(errno != EEXIST) {
- perror(subtrace_name);
- open_ret = -1;
- goto end;
- }
- }
-
- strncpy(path_channel, subchannel_name, PATH_MAX-1);
- path_channel_len = strlen(path_channel);
- path_channel[path_channel_len] = '/';
- path_channel_len++;
- path_channel_ptr = path_channel + path_channel_len;
-
- strncpy(path_trace, subtrace_name, PATH_MAX-1);
- path_trace_len = strlen(path_trace);
- path_trace[path_trace_len] = '/';
- path_trace_len++;
- path_trace_ptr = path_trace + path_trace_len;
-
- while((entry = readdir(channel_dir)) != NULL) {
-
- if(entry->d_name[0] == '.') continue;
-
- strncpy(path_channel_ptr, entry->d_name, PATH_MAX - path_channel_len);
- strncpy(path_trace_ptr, entry->d_name, PATH_MAX - path_trace_len);
-
- ret = stat(path_channel, &stat_buf);
- if(ret == -1) {
- perror(path_channel);
- continue;
- }
-
- printf("Channel file : %s\n", path_channel);
-
- if(S_ISDIR(stat_buf.st_mode)) {
-
- printf("Entering channel subdirectory...\n");
- ret = open_channel_trace_pairs(path_channel, path_trace, fd_pairs);
- if(ret < 0) continue;
- } else if(S_ISREG(stat_buf.st_mode)) {
- if(strncmp(entry->d_name, "flight-", sizeof("flight-")-1) != 0) {
- if(dump_flight_only) {
- printf("Skipping normal channel %s\n", path_channel);
- continue;
- }
- } else {
- if(dump_normal_only) {
- printf("Skipping flight channel %s\n", path_channel);
- continue;
- }
- }
- printf("Opening file.\n");
-
- fd_pairs->pair = realloc(fd_pairs->pair,
- ++fd_pairs->num_pairs * sizeof(struct fd_pair));
-
- /* Open the channel in read mode */
- fd_pairs->pair[fd_pairs->num_pairs-1].channel =
- open(path_channel, O_RDONLY | O_NONBLOCK);
- if(fd_pairs->pair[fd_pairs->num_pairs-1].channel == -1) {
- perror(path_channel);
- fd_pairs->num_pairs--;
- continue;
- }
- /* Open the trace in write mode, only append if append_mode */
- ret = stat(path_trace, &stat_buf);
- if(ret == 0) {
- if(append_mode) {
- printf("Appending to file %s as requested\n", path_trace);
-
- fd_pairs->pair[fd_pairs->num_pairs-1].trace =
- open(path_trace, O_WRONLY|O_APPEND,
- S_IRWXU|S_IRWXG|S_IRWXO);
-
- if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) {
- perror(path_trace);
- }
- } else {
- printf("File %s exists, cannot open. Try append mode.\n", path_trace);
- open_ret = -1;
- goto end;
- }
- } else {
- if(errno == ENOENT) {
- fd_pairs->pair[fd_pairs->num_pairs-1].trace =
- open(path_trace, O_WRONLY|O_CREAT|O_EXCL,
- S_IRWXU|S_IRWXG|S_IRWXO);
- if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) {
- perror(path_trace);
- }
- }
- }
- }
- }
-
-end:
- closedir(channel_dir);
-
- return open_ret;
-}
-
-
-int read_subbuffer(struct fd_pair *pair)
-{
- unsigned int consumed_old;
- int err, ret=0;
-
-
- err = ioctl(pair->channel, RELAY_GET_SUBBUF,
- &consumed_old);
- printf("cookie : %u\n", consumed_old);
- if(err != 0) {
- ret = errno;
- perror("Reserving sub buffer failed (everything is normal, it is due to concurrency)");
- goto get_error;
- }
-
- err = TEMP_FAILURE_RETRY(write(pair->trace,
- pair->mmap
- + (consumed_old & ((pair->n_subbufs * pair->subbuf_size)-1)),
- pair->subbuf_size));
-
- if(err < 0) {
- ret = errno;
- perror("Error in writing to file");
- goto write_error;
- }
-#if 0
- err = fsync(pair->trace);
- if(err < 0) {
- ret = errno;
- perror("Error in writing to file");
- goto write_error;
- }
-#endif //0
-write_error:
- err = ioctl(pair->channel, RELAY_PUT_SUBBUF, &consumed_old);
- if(err != 0) {
- ret = errno;
- if(errno == EFAULT) {
- perror("Error in unreserving sub buffer\n");
- } else if(errno == EIO) {
- perror("Reader has been pushed by the writer, last subbuffer corrupted.");
- /* FIXME : we may delete the last written buffer if we wish. */
- }
- goto get_error;
- }
-
-get_error:
- return ret;
-}
-
-
-
-int map_channels(struct channel_trace_fd *fd_pairs)
-{
- int i,j;
- int ret=0;
-
- if(fd_pairs->num_pairs <= 0) {
- printf("No channel to read\n");
- goto end;
- }
-
- /* Get the subbuf sizes and number */
-
- for(i=0;i<fd_pairs->num_pairs;i++) {
- struct fd_pair *pair = &fd_pairs->pair[i];
-
- ret = ioctl(pair->channel, RELAY_GET_N_SUBBUFS,
- &pair->n_subbufs);
- if(ret != 0) {
- perror("Error in getting the number of subbuffers");
- goto end;
- }
- ret = ioctl(pair->channel, RELAY_GET_SUBBUF_SIZE,
- &pair->subbuf_size);
- if(ret != 0) {
- perror("Error in getting the size of the subbuffers");
- goto end;
- }
- ret = pthread_mutex_init(&pair->mutex, NULL); /* Fast mutex */
- if(ret != 0) {
- perror("Error in mutex init");
- goto end;
- }
- }
-
- /* Mmap each FD */
- for(i=0;i<fd_pairs->num_pairs;i++) {
- struct fd_pair *pair = &fd_pairs->pair[i];
-
- pair->mmap = mmap(0, pair->subbuf_size * pair->n_subbufs, PROT_READ,
- MAP_SHARED, pair->channel, 0);
- if(pair->mmap == MAP_FAILED) {
- perror("Mmap error");
- goto munmap;
- }
- }
-
- goto end; /* success */
-
- /* Error handling */
- /* munmap only the successfully mmapped indexes */
-munmap:
- /* Munmap each FD */
- for(j=0;j<i;j++) {
- struct fd_pair *pair = &fd_pairs->pair[j];
- int err_ret;
-
- err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs);
- if(err_ret != 0) {
- perror("Error in munmap");
- }
- ret |= err_ret;
- }
-
-end:
- return ret;
-
-
-}
-
-
-int unmap_channels(struct channel_trace_fd *fd_pairs)
-{
- int j;
- int ret=0;
-
- /* Munmap each FD */
- for(j=0;j<fd_pairs->num_pairs;j++) {
- struct fd_pair *pair = &fd_pairs->pair[j];
- int err_ret;
-
- err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs);
- if(err_ret != 0) {
- perror("Error in munmap");
- }
- ret |= err_ret;
- err_ret = pthread_mutex_destroy(&pair->mutex);
- if(err_ret != 0) {
- perror("Error in mutex destroy");
- }
- ret |= err_ret;
- }
-
- return ret;
-}
-
-
-/* read_channels
- *
- * Thread worker.
- *
- * Read the debugfs channels and write them in the paired tracefiles.
- *
- * @fd_pairs : paired channels and trace files.
- *
- * returns (void*)0 on success, (void*)-1 on error.
- *
- * Note that the high priority polled channels are consumed first. We then poll
- * again to see if these channels are still in priority. Only when no
- * high priority channel is left, we start reading low priority channels.
- *
- * Note that a channel is considered high priority when the buffer is almost
- * full.
- */
-
-void * read_channels(void *arg)
-{
- struct pollfd *pollfd;
- int i,j;
- int num_rdy, num_hup;
- int high_prio;
- int ret = 0;
- struct channel_trace_fd *fd_pairs = (struct channel_trace_fd *)arg;
-
- /* Start polling the FD */
-
- pollfd = malloc(fd_pairs->num_pairs * sizeof(struct pollfd));
-
- /* Note : index in pollfd is the same index as fd_pair->pair */
- for(i=0;i<fd_pairs->num_pairs;i++) {
- pollfd[i].fd = fd_pairs->pair[i].channel;
- pollfd[i].events = POLLIN|POLLPRI;
- }
-
- while(1) {
- high_prio = 0;
- num_hup = 0;
-#ifdef DEBUG
- printf("Press a key for next poll...\n");
- char buf[1];
- read(STDIN_FILENO, &buf, 1);
- printf("Next poll (polling %d fd) :\n", fd_pairs->num_pairs);
-#endif //DEBUG
-
- /* Have we received a signal ? */
- if(quit_program) break;
-
- num_rdy = poll(pollfd, fd_pairs->num_pairs, -1);
- if(num_rdy == -1) {
- perror("Poll error");
- goto free_fd;
- }
-
- printf("Data received\n");
-
- for(i=0;i<fd_pairs->num_pairs;i++) {
- switch(pollfd[i].revents) {
- case POLLERR:
- printf("Error returned in polling fd %d.\n", pollfd[i].fd);
- num_hup++;
- break;
- case POLLHUP:
- printf("Polling fd %d tells it has hung up.\n", pollfd[i].fd);
- num_hup++;
- break;
- case POLLNVAL:
- printf("Polling fd %d tells fd is not open.\n", pollfd[i].fd);
- num_hup++;
- break;
- case POLLPRI:
- if(pthread_mutex_trylock(&fd_pairs->pair[i].mutex) == 0) {
- printf("Urgent read on fd %d\n", pollfd[i].fd);
- /* Take care of high priority channels first. */
- high_prio = 1;
- /* it's ok to have an unavailable subbuffer */
- ret = read_subbuffer(&fd_pairs->pair[i]);
- if(ret == EAGAIN) ret = 0;
-
- ret = pthread_mutex_unlock(&fd_pairs->pair[i].mutex);
- if(ret)
- printf("Error in mutex unlock : %s\n", strerror(ret));
- }
- break;
- }
- }
- /* If every FD has hung up, we end the read loop here */
- if(num_hup == fd_pairs->num_pairs) break;
-
- if(!high_prio) {
- for(i=0;i<fd_pairs->num_pairs;i++) {
- switch(pollfd[i].revents) {
- case POLLIN:
- if(pthread_mutex_trylock(&fd_pairs->pair[i].mutex) == 0) {
- /* Take care of low priority channels. */
- printf("Normal read on fd %d\n", pollfd[i].fd);
- /* it's ok to have an unavailable subbuffer */
- ret = read_subbuffer(&fd_pairs->pair[i]);
- if(ret == EAGAIN) ret = 0;
-
- ret = pthread_mutex_unlock(&fd_pairs->pair[i].mutex);
- if(ret)
- printf("Error in mutex unlock : %s\n", strerror(ret));
- }
- break;
- }
- }
- }
-
- }
-
-free_fd:
- free(pollfd);
-
-end:
- return (void*)ret;
-}
-
-
-void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs)
-{
- int i;
- int ret;
-
- for(i=0;i<fd_pairs->num_pairs;i++) {
- ret = close(fd_pairs->pair[i].channel);
- if(ret == -1) perror("Close error on channel");
- ret = close(fd_pairs->pair[i].trace);
- if(ret == -1) perror("Close error on trace");
- }
- free(fd_pairs->pair);
-}
-
-int main(int argc, char ** argv)
-{
- int ret = 0;
- struct channel_trace_fd fd_pairs = { NULL, 0 };
- struct sigaction act;
- pthread_t *tids;
- unsigned int i;
- void *tret;
-
- ret = parse_arguments(argc, argv);
-
- if(ret != 0) show_arguments();
- if(ret < 0) return EINVAL;
- if(ret > 0) return 0;
-
- show_info();
-
- if(daemon_mode) {
- ret = daemon(0, 0);
-
- if(ret == -1) {
- perror("An error occured while daemonizing.");
- exit(-1);
- }
- }
-
- /* Connect the signal handlers */
- act.sa_handler = handler;
- act.sa_flags = 0;
- sigemptyset(&(act.sa_mask));
- sigaddset(&(act.sa_mask), SIGTERM);
- sigaddset(&(act.sa_mask), SIGQUIT);
- sigaddset(&(act.sa_mask), SIGINT);
- sigaction(SIGTERM, &act, NULL);
- sigaction(SIGQUIT, &act, NULL);
- sigaction(SIGINT, &act, NULL);
-
-
- if(ret = open_channel_trace_pairs(channel_name, trace_name, &fd_pairs))
- goto close_channel;
-
- if(ret = map_channels(&fd_pairs))
- goto close_channel;
-
- tids = malloc(sizeof(pthread_t) * num_threads);
- for(i=0; i<num_threads; i++) {
- ret = pthread_create(&tids[i], NULL, read_channels, &fd_pairs);
- if(ret) {
- perror("Error creating thread");
- break;
- }
- }
-
- for(i=0; i<num_threads; i++) {
- ret = pthread_join(tids[i], &tret);
- if(ret) {
- perror("Error joining thread");
- break;
- }
- if((int)tret != 0) {
- printf("Error %s occured in thread %u\n", strerror((int)tret), i);
- }
- }
-
- free(tids);
-
- ret |= unmap_channels(&fd_pairs);
-
-close_channel:
- close_channel_trace_pairs(&fd_pairs);
-
- return ret;
-}
projects / ltt-control.git / blobdiff