-SUBDIRS = liblttctl lttctl lttd specs
+SUBDIRS = liblttctl lttctl liblttd lttd specs
#AC_SUBST(CPPFLAGS)
lttctlincludedir="${includedir}/liblttctl"
+liblttdincludedir="${includedir}/liblttd"
AC_SUBST(lttctlincludedir)
+AC_SUBST(liblttdincludedir)
AC_SUBST(UTIL_LIBS)
AC_SUBST(THREAD_LIBS)
AC_SUBST(DEFAULT_INCLUDES)
AC_CONFIG_FILES([Makefile
liblttctl/Makefile
lttctl/Makefile
+ liblttd/Makefile
lttd/Makefile
specs/Makefile])
AC_OUTPUT
--- /dev/null
+
+
+lib_LTLIBRARIES = liblttd.la
+liblttd_la_SOURCES = liblttd.c
+
+liblttdinclude_HEADERS = \
+ liblttd.h
--- /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.
+ *
+ * CPU hot-plugging is supported using inotify.
+ *
+ * Copyright 2005 -
+ * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "liblttd.h"
+
+#define _REENTRANT
+#define _GNU_SOURCE
+#include <features.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <stdlib.h>
+#include <dirent.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/poll.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <asm/ioctls.h>
+
+#include <linux/version.h>
+
+/* Relayfs IOCTL */
+#include <asm/ioctl.h>
+#include <asm/types.h>
+
+/* Get the next sub buffer that can be read. */
+#define RELAY_GET_SB _IOR(0xF5, 0x00,__u32)
+/* Release the oldest reserved (by "get") sub buffer. */
+#define RELAY_PUT_SB _IOW(0xF5, 0x01,__u32)
+/* returns the number of sub buffers in the per cpu channel. */
+#define RELAY_GET_N_SB _IOR(0xF5, 0x02,__u32)
+/* returns the size of the current sub buffer. */
+#define RELAY_GET_SB_SIZE _IOR(0xF5, 0x03, __u32)
+/* returns the size of data to consume in the current sub-buffer. */
+#define RELAY_GET_MAX_SB_SIZE _IOR(0xF5, 0x04, __u32)
+
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
+#include <sys/inotify.h>
+
+#define HAS_INOTIFY
+#else
+static inline int inotify_init (void)
+{
+ return -1;
+}
+
+static inline int inotify_add_watch (int fd, const char *name, __u32 mask)
+{
+ return 0;
+}
+
+static inline int inotify_rm_watch (int fd, __u32 wd)
+{
+ return 0;
+}
+#undef HAS_INOTIFY
+#endif
+
+struct liblttd_callbacks *callbacks;
+
+struct channel_trace_fd {
+ struct fd_pair *pair;
+ int num_pairs;
+};
+
+struct inotify_watch {
+ int wd;
+ char path_channel[PATH_MAX];
+ char *base_path_channel;
+};
+
+struct inotify_watch_array {
+ struct inotify_watch *elem;
+ int num;
+};
+
+struct channel_trace_fd fd_pairs = { NULL, 0 };
+int inotify_fd = -1;
+struct inotify_watch_array inotify_watch_array = { NULL, 0 };
+
+/* protects fd_pairs and inotify_watch_array */
+pthread_rwlock_t fd_pairs_lock = PTHREAD_RWLOCK_INITIALIZER;
+
+static char *channel_name = NULL;
+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;
+static int verbose_mode = 0;
+
+#define printf_verbose(fmt, args...) \
+ do { \
+ if (verbose_mode) \
+ printf(fmt, ##args); \
+ } while (0)
+
+
+int open_buffer_file(char *filename, char *path_channel,
+ char *base_path_channel, struct channel_trace_fd *fd_pairs)
+{
+ int open_ret = 0;
+ int ret = 0;
+
+ if(strncmp(filename, "flight-", sizeof("flight-")-1) != 0) {
+ if(dump_flight_only) {
+ printf_verbose("Skipping normal channel %s\n",
+ path_channel);
+ return 0;
+ }
+ } else {
+ if(dump_normal_only) {
+ printf_verbose("Skipping flight channel %s\n",
+ path_channel);
+ return 0;
+ }
+ }
+ printf_verbose("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--;
+ return 0; /* continue */
+ }
+
+ if(callbacks->on_open_channel) ret = callbacks->on_open_channel(
+ callbacks, &fd_pairs->pair[fd_pairs->num_pairs-1],
+ base_path_channel);
+
+ if(ret != 0) {
+ open_ret = -1;
+ close(fd_pairs->pair[fd_pairs->num_pairs-1].channel);
+ fd_pairs->num_pairs--;
+ goto end;
+ }
+
+end:
+ return open_ret;
+}
+
+int open_channel_trace_pairs(char *subchannel_name,
+ char *base_subchannel_name,
+ struct channel_trace_fd *fd_pairs, int *inotify_fd,
+ struct inotify_watch_array *iwatch_array)
+{
+ 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 *base_subchannel_ptr;
+
+ int open_ret = 0;
+
+ if(channel_dir == NULL) {
+ perror(subchannel_name);
+ open_ret = ENOENT;
+ goto end;
+ }
+
+ printf_verbose("Calling on new channels folder");
+ if(callbacks->on_new_channels_folder) ret = callbacks->
+ on_new_channels_folder(callbacks,
+ base_subchannel_name);
+ if(ret == -1) {
+ 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;
+ base_subchannel_ptr = path_channel +
+ (base_subchannel_name - subchannel_name);
+
+#ifdef HAS_INOTIFY
+ iwatch_array->elem = realloc(iwatch_array->elem,
+ ++iwatch_array->num * sizeof(struct inotify_watch));
+
+ printf_verbose("Adding inotify for channel %s\n", path_channel);
+ iwatch_array->elem[iwatch_array->num-1].wd = inotify_add_watch(*inotify_fd, path_channel, IN_CREATE);
+ strcpy(iwatch_array->elem[iwatch_array->num-1].path_channel, path_channel);
+ iwatch_array->elem[iwatch_array->num-1].base_path_channel =
+ iwatch_array->elem[iwatch_array->num-1].path_channel +
+ (base_subchannel_name - subchannel_name);
+ printf_verbose("Added inotify for channel %s, wd %u\n",
+ iwatch_array->elem[iwatch_array->num-1].path_channel,
+ iwatch_array->elem[iwatch_array->num-1].wd);
+#endif
+
+ while((entry = readdir(channel_dir)) != NULL) {
+
+ if(entry->d_name[0] == '.') continue;
+
+ strncpy(path_channel_ptr, entry->d_name, PATH_MAX - path_channel_len);
+
+ ret = stat(path_channel, &stat_buf);
+ if(ret == -1) {
+ perror(path_channel);
+ continue;
+ }
+
+ printf_verbose("Channel file : %s\n", path_channel);
+
+ if(S_ISDIR(stat_buf.st_mode)) {
+
+ printf_verbose("Entering channel subdirectory...\n");
+ ret = open_channel_trace_pairs(path_channel, base_subchannel_ptr, fd_pairs,
+ inotify_fd, iwatch_array);
+ if(ret < 0) continue;
+ } else if(S_ISREG(stat_buf.st_mode)) {
+ open_ret = open_buffer_file(entry->d_name, path_channel, base_subchannel_ptr,
+ fd_pairs);
+ if(open_ret)
+ goto end;
+ }
+ }
+
+end:
+ closedir(channel_dir);
+
+ return open_ret;
+}
+
+
+int read_subbuffer(struct fd_pair *pair)
+{
+ unsigned int consumed_old, len;
+ int err;
+ long ret;
+ off_t offset;
+
+
+ err = ioctl(pair->channel, RELAY_GET_SB, &consumed_old);
+ printf_verbose("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 = ioctl(pair->channel, RELAY_GET_SB_SIZE, &len);
+ if(err != 0) {
+ ret = errno;
+ perror("Getting sub-buffer len failed.");
+ goto get_error;
+ }
+
+ if(callbacks->on_read_subbuffer) ret = callbacks->on_read_subbuffer(
+ callbacks, pair, len);
+
+write_error:
+ ret = 0;
+ err = ioctl(pair->channel, RELAY_PUT_SB, &consumed_old);
+ if(err != 0) {
+ ret = errno;
+ if(errno == EFAULT) {
+ perror("Error in unreserving sub buffer\n");
+ } else if(errno == EIO) {
+ /* Should never happen with newer LTTng versions */
+ perror("Reader has been pushed by the writer, last sub-buffer corrupted.");
+ }
+ goto get_error;
+ }
+
+get_error:
+ return ret;
+}
+
+
+int map_channels(struct channel_trace_fd *fd_pairs,
+ int idx_begin, int idx_end)
+{
+ 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=idx_begin;i<idx_end;i++) {
+ struct fd_pair *pair = &fd_pairs->pair[i];
+
+ ret = ioctl(pair->channel, RELAY_GET_N_SB, &pair->n_sb);
+ if(ret != 0) {
+ perror("Error in getting the number of sub-buffers");
+ goto end;
+ }
+ ret = ioctl(pair->channel, RELAY_GET_MAX_SB_SIZE,
+ &pair->max_sb_size);
+ if(ret != 0) {
+ perror("Error in getting the max sub-buffer size");
+ goto end;
+ }
+ ret = pthread_mutex_init(&pair->mutex, NULL); /* Fast mutex */
+ if(ret != 0) {
+ perror("Error in mutex init");
+ goto end;
+ }
+ }
+
+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 = pthread_mutex_destroy(&pair->mutex);
+ if(err_ret != 0) {
+ perror("Error in mutex destroy");
+ }
+ ret |= err_ret;
+ }
+
+ return ret;
+}
+
+#ifdef HAS_INOTIFY
+/* Inotify event arrived.
+ *
+ * Only support add file for now.
+ */
+
+int read_inotify(int inotify_fd,
+ struct channel_trace_fd *fd_pairs,
+ struct inotify_watch_array *iwatch_array)
+{
+ char buf[sizeof(struct inotify_event) + PATH_MAX];
+ char path_channel[PATH_MAX];
+ ssize_t len;
+ struct inotify_event *ievent;
+ size_t offset;
+ unsigned int i;
+ int ret;
+ int old_num;
+
+ offset = 0;
+ len = read(inotify_fd, buf, sizeof(struct inotify_event) + PATH_MAX);
+ if(len < 0) {
+
+ if(errno == EAGAIN)
+ return 0; /* another thread got the data before us */
+
+ printf("Error in read from inotify FD %s.\n", strerror(len));
+ return -1;
+ }
+ while(offset < len) {
+ ievent = (struct inotify_event *)&(buf[offset]);
+ for(i=0; i<iwatch_array->num; i++) {
+ if(iwatch_array->elem[i].wd == ievent->wd &&
+ ievent->mask == IN_CREATE) {
+ printf_verbose(
+ "inotify wd %u event mask : %u for %s%s\n",
+ ievent->wd, ievent->mask,
+ iwatch_array->elem[i].path_channel,
+ ievent->name);
+ old_num = fd_pairs->num_pairs;
+ strcpy(path_channel, iwatch_array->elem[i].path_channel);
+ strcat(path_channel, ievent->name);
+ if(ret = open_buffer_file(ievent->name, path_channel,
+ path_channel + (iwatch_array->elem[i].base_path_channel -
+ iwatch_array->elem[i].path_channel), fd_pairs)) {
+ printf("Error opening buffer file\n");
+ return -1;
+ }
+ if(ret = map_channels(fd_pairs, old_num, fd_pairs->num_pairs)) {
+ printf("Error mapping channel\n");
+ return -1;
+ }
+
+ }
+ }
+ offset += sizeof(*ievent) + ievent->len;
+ }
+}
+#endif //HAS_INOTIFY
+
+/* read_channels
+ *
+ * Thread worker.
+ *
+ * Read the debugfs channels and write them in the paired tracefiles.
+ *
+ * @fd_pairs : paired channels and trace files.
+ *
+ * returns 0 on success, -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.
+ */
+
+int read_channels(unsigned long thread_num, struct channel_trace_fd *fd_pairs,
+ int inotify_fd, struct inotify_watch_array *iwatch_array)
+{
+ struct pollfd *pollfd = NULL;
+ int num_pollfd;
+ int i,j;
+ int num_rdy, num_hup;
+ int high_prio;
+ int ret = 0;
+ int inotify_fds;
+ unsigned int old_num;
+
+#ifdef HAS_INOTIFY
+ inotify_fds = 1;
+#else
+ inotify_fds = 0;
+#endif
+
+ pthread_rwlock_rdlock(&fd_pairs_lock);
+
+ /* Start polling the FD. Keep one fd for inotify */
+ pollfd = malloc((inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd));
+
+#ifdef HAS_INOTIFY
+ pollfd[0].fd = inotify_fd;
+ pollfd[0].events = POLLIN|POLLPRI;
+#endif
+
+ for(i=0;i<fd_pairs->num_pairs;i++) {
+ pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel;
+ pollfd[inotify_fds+i].events = POLLIN|POLLPRI;
+ }
+ num_pollfd = inotify_fds + fd_pairs->num_pairs;
+
+
+ pthread_rwlock_unlock(&fd_pairs_lock);
+
+ 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", num_pollfd);
+#endif //DEBUG
+
+ /* Have we received a signal ? */
+ if(quit_program) break;
+
+ num_rdy = poll(pollfd, num_pollfd, -1);
+
+ if(num_rdy == -1) {
+ perror("Poll error");
+ goto free_fd;
+ }
+
+ printf_verbose("Data received\n");
+#ifdef HAS_INOTIFY
+ switch(pollfd[0].revents) {
+ case POLLERR:
+ printf_verbose(
+ "Error returned in polling inotify fd %d.\n",
+ pollfd[0].fd);
+ break;
+ case POLLHUP:
+ printf_verbose(
+ "Polling inotify fd %d tells it has hung up.\n",
+ pollfd[0].fd);
+ break;
+ case POLLNVAL:
+ printf_verbose(
+ "Polling inotify fd %d tells fd is not open.\n",
+ pollfd[0].fd);
+ break;
+ case POLLPRI:
+ case POLLIN:
+ printf_verbose(
+ "Polling inotify fd %d : data ready.\n",
+ pollfd[0].fd);
+
+ pthread_rwlock_wrlock(&fd_pairs_lock);
+ read_inotify(inotify_fd, fd_pairs, iwatch_array);
+ pthread_rwlock_unlock(&fd_pairs_lock);
+
+ break;
+ }
+#endif
+
+ for(i=inotify_fds;i<num_pollfd;i++) {
+ switch(pollfd[i].revents) {
+ case POLLERR:
+ printf_verbose(
+ "Error returned in polling fd %d.\n",
+ pollfd[i].fd);
+ num_hup++;
+ break;
+ case POLLHUP:
+ printf_verbose(
+ "Polling fd %d tells it has hung up.\n",
+ pollfd[i].fd);
+ num_hup++;
+ break;
+ case POLLNVAL:
+ printf_verbose(
+ "Polling fd %d tells fd is not open.\n",
+ pollfd[i].fd);
+ num_hup++;
+ break;
+ case POLLPRI:
+ pthread_rwlock_rdlock(&fd_pairs_lock);
+ if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) {
+ printf_verbose(
+ "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 sub-buffer */
+ ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]);
+ if(ret == EAGAIN) ret = 0;
+
+ ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex);
+ if(ret)
+ printf("Error in mutex unlock : %s\n", strerror(ret));
+ }
+ pthread_rwlock_unlock(&fd_pairs_lock);
+ break;
+ }
+ }
+ /* If every buffer FD has hung up, we end the read loop here */
+ if(num_hup == num_pollfd - inotify_fds) break;
+
+ if(!high_prio) {
+ for(i=inotify_fds;i<num_pollfd;i++) {
+ switch(pollfd[i].revents) {
+ case POLLIN:
+ pthread_rwlock_rdlock(&fd_pairs_lock);
+ if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) {
+ /* Take care of low priority channels. */
+ printf_verbose(
+ "Normal read on fd %d\n",
+ pollfd[i].fd);
+ /* it's ok to have an unavailable subbuffer */
+ ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]);
+ if(ret == EAGAIN) ret = 0;
+
+ ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex);
+ if(ret)
+ printf("Error in mutex unlock : %s\n", strerror(ret));
+ }
+ pthread_rwlock_unlock(&fd_pairs_lock);
+ break;
+ }
+ }
+ }
+
+ /* Update pollfd array if an entry was added to fd_pairs */
+ pthread_rwlock_rdlock(&fd_pairs_lock);
+ if((inotify_fds + fd_pairs->num_pairs) != num_pollfd) {
+ pollfd = realloc(pollfd,
+ (inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd));
+ for(i=num_pollfd-inotify_fds;i<fd_pairs->num_pairs;i++) {
+ pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel;
+ pollfd[inotify_fds+i].events = POLLIN|POLLPRI;
+ }
+ num_pollfd = fd_pairs->num_pairs + inotify_fds;
+ }
+ pthread_rwlock_unlock(&fd_pairs_lock);
+
+ /* NB: If the fd_pairs structure is updated by another thread from this
+ * point forward, the current thread will wait in the poll without
+ * monitoring the new channel. However, this thread will add the
+ * new channel on next poll (and this should not take too much time
+ * on a loaded system).
+ *
+ * This event is quite unlikely and can only occur if a CPU is
+ * hot-plugged while multple lttd threads are running.
+ */
+ }
+
+free_fd:
+ free(pollfd);
+
+end:
+ return ret;
+}
+
+
+void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs, int inotify_fd,
+ struct inotify_watch_array *iwatch_array)
+{
+ 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");
+ if(callbacks->on_close_channel) {
+ ret = callbacks->on_close_channel(
+ callbacks, &fd_pairs->pair[i]);
+ if(ret != 0) perror("Error on close channel callback");
+ }
+ }
+ free(fd_pairs->pair);
+ free(iwatch_array->elem);
+}
+
+/* Thread worker */
+void * thread_main(void *arg)
+{
+ long ret = 0;
+ unsigned long thread_num = (unsigned long)arg;
+
+ if(callbacks->on_new_thread)
+ ret = callbacks->on_new_thread(callbacks, thread_num);
+
+ if (ret < 0) {
+ return (void*)ret;
+ }
+ ret = read_channels(thread_num, &fd_pairs, inotify_fd, &inotify_watch_array);
+
+ if(callbacks->on_close_thread)
+ callbacks->on_close_thread(callbacks, thread_num);
+
+ return (void*)ret;
+}
+
+/*on_close_thread has to be reentrant, it'll be called by many threads*/
+int(*on_close_thread)(struct liblttd_callbacks *data, unsigned long thread_num);
+
+int channels_init()
+{
+ int ret = 0;
+
+ inotify_fd = inotify_init();
+ fcntl(inotify_fd, F_SETFL, O_NONBLOCK);
+
+ if(ret = open_channel_trace_pairs(channel_name,
+ channel_name + strlen(channel_name), &fd_pairs,
+ &inotify_fd, &inotify_watch_array))
+ goto close_channel;
+ if (fd_pairs.num_pairs == 0) {
+ printf("No channel available for reading, exiting\n");
+ ret = -ENOENT;
+ goto close_channel;
+ }
+ if(ret = map_channels(&fd_pairs, 0, fd_pairs.num_pairs))
+ goto close_channel;
+ return 0;
+
+close_channel:
+ close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array);
+ if(inotify_fd >= 0)
+ close(inotify_fd);
+ return ret;
+}
+
+int liblttd_start(char *channel_path, unsigned long n_threads,
+ int flight_only, int normal_only, int verbose,
+ struct liblttd_callbacks *user_data){
+ int ret = 0;
+ pthread_t *tids;
+ unsigned long i;
+ void *tret;
+
+ channel_name = channel_path;
+ num_threads = n_threads;
+ dump_flight_only = flight_only;
+ dump_normal_only = normal_only;
+ verbose_mode = verbose;
+ callbacks = user_data;
+
+ if(ret = channels_init())
+ return ret;
+
+ tids = malloc(sizeof(pthread_t) * num_threads);
+ for(i=0; i<num_threads; i++) {
+
+ ret = pthread_create(&tids[i], NULL, thread_main, (void*)i);
+ 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((long)tret != 0) {
+ printf("Error %s occured in thread %ld\n",
+ strerror((long)tret), i);
+ }
+ }
+
+ free(tids);
+ ret = unmap_channels(&fd_pairs);
+ close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array);
+ if(inotify_fd >= 0)
+ close(inotify_fd);
+
+ if(callbacks->on_trace_end) callbacks->on_trace_end(callbacks);
+
+ return ret;
+}
+
+int liblttd_stop() {
+ quit_program = 1;
+ return 0;
+}
+
--- /dev/null
+/* liblttd header file
+ *
+ * Copyright 2010-
+ * Oumarou Dicko <oumarou.dicko@polymtl.ca>
+ * Michael Sills-Lavoie <michael.sills-lavoie@polymtl.ca>
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef _LIBLTTD_H
+#define _LIBLTTD_H
+
+#include <pthread.h>
+
+/**
+* This structure contains the data associated with the channel file descriptor.
+* The lib user can use user_data to store the data associated to the specified
+* channel. The lib user can read but MUST NOT change the other attributes.
+*/
+struct fd_pair {
+ /**
+ * This is the channel file descriptor.
+ */
+ int channel;
+
+ /**
+ * This is the number of subbuffer for this channel.
+ */
+ unsigned int n_sb;
+
+ /**
+ * This is the subbuffer size for this channel.
+ */
+ unsigned int max_sb_size;
+
+ /**
+ * Not used anymore.
+ */
+ void *mmap;
+
+ /**
+ * This is a mutex for internal library usage.
+ */
+ pthread_mutex_t mutex;
+
+ /**
+ * Library user data.
+ */
+ void *user_data;
+};
+
+/**
+* This structure contains the necessary callbacks for a tracing session. The
+* user can set the unnecessary functions to NULL if he does not need them.
+*/
+struct liblttd_callbacks {
+ /**
+ * This callback is called after a channel file is open.
+ *
+ * @args data This argument is a pointeur to the callbacks struct that
+ * has been passed to the lib.
+ * @args pair This structure contains the data associated with the
+ * channel file descriptor. The lib user can use user_data to
+ * store the data associated to the specified channel.
+ * @args relative_channel_path This argument represents a relative path
+ * to the channel file. This path is relative to the root
+ * folder of the trace channels.
+ *
+ * @return Should return 0 if the callback succeeds else not 0.
+ */
+ int(*on_open_channel)(struct liblttd_callbacks *data,
+ struct fd_pair *pair, char *relative_channel_path);
+
+ /**
+ * This callback is called after a channel file is closed.
+ *
+ * @remarks After a channel file has been closed, it will never be read
+ * again.
+ *
+ * @args data This argument is a pointeur to the callbacks struct that
+ * has been passed to the lib.
+ * @args pair This structure contains the data associated with the
+ * channel file descriptor. The lib user should clean
+ * user_data at this time.
+ *
+ * @return Should return 0 if the callback succeeds else not 0.
+ */
+ int(*on_close_channel)(struct liblttd_callbacks *data,
+ struct fd_pair *pair);
+
+
+ /**
+ * This callback is called when the library enter in a new subfolder
+ * while it is scanning the trace channel tree. It can be used to create
+ * the output file structure of the trace.
+ *
+ * @args data This argument is a pointeur to the callbacks struct that
+ * has been passed to the lib.
+ * @args relative_folder_path This argument represents a relative path
+ * to the channel folder. This path is relative to the root
+ * folder of the trace channels.
+ *
+ * @return Should return 0 if the callback succeeds else not 0.
+ */
+ int(*on_new_channels_folder)(struct liblttd_callbacks *data,
+ char *relative_folder_path);
+
+ /**
+ * This callback is called after a subbuffer is a reserved.
+ *
+ * @attention It has to be thread safe, it'll be called by many threads.
+ *
+ * @args data This argument is a pointeur to the callbacks struct that
+ * has been passed to the lib.
+ * @args pair This structure contains the data associated with the
+ * channel file descriptor. The lib user should clean
+ * user_data at this time.
+ * @args len This argument represents the length the data that has to be
+ * read.
+ *
+ * @return Should return 0 if the callback succeeds else not 0.
+ */
+ int(*on_read_subbuffer)(struct liblttd_callbacks *data,
+ struct fd_pair *pair, unsigned int len);
+
+ /**
+ * This callback is called at the very end of the tracing session. At
+ * this time, all the channels have been closed and the threads have been
+ * destroyed.
+ *
+ * @remarks After this callback is called, no other callback will be
+ * called again.
+ *
+ * @attention It has to be thread safe, it'll be called by many threads.
+ *
+ * @args data This argument is a pointeur to the callbacks struct that
+ * has been passed to the lib.
+ *
+ * @return Should return 0 if the callback succeeds else not 0.
+ */
+ int(*on_trace_end)(struct liblttd_callbacks *data);
+
+ /**
+ * This callback is called after a new thread has been created.
+ *
+ * @attention It has to be thread safe, it'll be called by many threads.
+ *
+ * @args data This argument is a pointeur to the callbacks struct that
+ * has been passed to the lib.
+ * @args thread_num This argument represents the id of the thread.
+ *
+ * @return Should return 0 if the callback succeeds else not 0.
+ */
+ int(*on_new_thread)(struct liblttd_callbacks *data,
+ unsigned long thread_num);
+
+ /**
+ * This callback is called just before a thread is destroyed.
+ *
+ * @attention It has to be thread safe, it'll be called by many threads.
+ *
+ * @args data This argument is a pointeur to the callbacks struct that
+ * has been passed to the lib.
+ * @args thread_num This argument represents the number of the thread.
+ *
+ * @return Should return 0 if the callback succeeds else not 0.
+ */
+ int(*on_close_thread)(struct liblttd_callbacks *data,
+ unsigned long thread_num);
+
+ /**
+ * This is where the user can put the library's data.
+ */
+ void *user_data;
+};
+
+/**
+* This function is called to start a new tracing session.
+*
+* @attention It has to be thread safe, it'll be called by many threads.
+*
+* @args channel_path This argument is a path to the root folder of the trace's
+* channels.
+* @args n_threads This argument represents the number of threads that will be
+* used by the library.
+* @args flight_only If this argument to set to 1, only the channel that are in
+* flight recorder mode will be recorded.
+* @args normal_only If this argument to set to 1, only the channel that are in
+* normal mode will be recorded.
+* @args verbose If this argument to set to 1, more informations will be printed.
+* @args user_data This argument is a pointeur to the callbacks struct that
+* contains the user's functions.
+*
+* @return Return 0 if the function succeeds else not 0.
+*/
+int liblttd_start(char *channel_path, unsigned long n_threads,
+ int flight_only, int normal_only, int verbose,
+ struct liblttd_callbacks *user_data);
+
+/**
+* This function is called to stop a tracing session.
+*
+* @return Return 0 if the function succeeds.
+*/
+int liblttd_stop();
+
+#endif /*_LIBLTTD_H */
+
lttd_SOURCES = lttd.c
+lttd_DEPENDENCIES = ../liblttd/liblttd.la
+lttd_LDADD = $(lttd_DEPENDENCIES)
+
#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>
-#include <sys/syscall.h>
-#include <unistd.h>
-#include <asm/ioctls.h>
-
-#include <linux/version.h>
-
-/* Relayfs IOCTL */
-#include <asm/ioctl.h>
-#include <asm/types.h>
-
-/* Get the next sub buffer that can be read. */
-#define RELAY_GET_SB _IOR(0xF5, 0x00,__u32)
-/* Release the oldest reserved (by "get") sub buffer. */
-#define RELAY_PUT_SB _IOW(0xF5, 0x01,__u32)
-/* returns the number of sub buffers in the per cpu channel. */
-#define RELAY_GET_N_SB _IOR(0xF5, 0x02,__u32)
-/* returns the size of the current sub buffer. */
-#define RELAY_GET_SB_SIZE _IOR(0xF5, 0x03, __u32)
-/* returns the size of data to consume in the current sub-buffer. */
-#define RELAY_GET_MAX_SB_SIZE _IOR(0xF5, 0x04, __u32)
-
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
-#include <sys/inotify.h>
-#if 0 /* should now be provided by libc. */
-/* From the inotify-tools 2.6 package */
-static inline int inotify_init (void)
-{
- return syscall (__NR_inotify_init);
-}
-
-static inline int inotify_add_watch (int fd, const char *name, __u32 mask)
-{
- return syscall (__NR_inotify_add_watch, fd, name, mask);
-}
-
-static inline int inotify_rm_watch (int fd, __u32 wd)
-{
- return syscall (__NR_inotify_rm_watch, fd, wd);
-}
-#endif //0
-#define HAS_INOTIFY
-#else
-static inline int inotify_init (void)
-{
- return -1;
-}
+#include <errno.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <sys/stat.h>
-static inline int inotify_add_watch (int fd, const char *name, __u32 mask)
-{
- return 0;
-}
+#include <liblttd/liblttd.h>
-static inline int inotify_rm_watch (int fd, __u32 wd)
-{
- return 0;
-}
-#undef HAS_INOTIFY
-#endif
-
-struct fd_pair {
- int channel;
+struct lttd_channel_data {
int trace;
- unsigned int n_sb;
- unsigned int max_sb_size;
- void *mmap;
- pthread_mutex_t mutex;
-};
-
-struct channel_trace_fd {
- struct fd_pair *pair;
- int num_pairs;
-};
-
-struct inotify_watch {
- int wd;
- char path_channel[PATH_MAX];
- char path_trace[PATH_MAX];
-};
-
-struct inotify_watch_array {
- struct inotify_watch *elem;
- int num;
};
-static __thread int thread_pipe[2];
-
-struct channel_trace_fd fd_pairs = { NULL, 0 };
-int inotify_fd = -1;
-struct inotify_watch_array inotify_watch_array = { NULL, 0 };
-
-/* protects fd_pairs and inotify_watch_array */
-pthread_rwlock_t fd_pairs_lock = PTHREAD_RWLOCK_INITIALIZER;
-
-
+static char path_trace[PATH_MAX];
+static char *end_path_trace;
+static int path_trace_len = 0;
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;
static int verbose_mode = 0;
+static __thread int thread_pipe[2];
+
#define printf_verbose(fmt, args...) \
do { \
if (verbose_mode) \
{
int ret = 0;
int argn = 1;
-
+
if(argc == 2) {
if(strcmp(argv[1], "-h") == 0) {
return 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;
}
static void handler(int signo)
{
printf("Signal %d received : exiting cleanly\n", signo);
- quit_program = 1;
+ liblttd_stop();
}
-
-int open_buffer_file(char *filename, char *path_channel, char *path_trace,
- struct channel_trace_fd *fd_pairs)
+int lttd_on_open_channel(struct liblttd_callbacks *data, struct fd_pair *pair, char *relative_channel_path)
{
int open_ret = 0;
- int ret = 0;
+ int ret;
struct stat stat_buf;
+ struct lttd_channel_data *channel_data;
- if(strncmp(filename, "flight-", sizeof("flight-")-1) != 0) {
- if(dump_flight_only) {
- printf_verbose("Skipping normal channel %s\n",
- path_channel);
- return 0;
- }
- } else {
- if(dump_normal_only) {
- printf_verbose("Skipping flight channel %s\n",
- path_channel);
- return 0;
- }
- }
- printf_verbose("Opening file.\n");
-
- fd_pairs->pair = realloc(fd_pairs->pair,
- ++fd_pairs->num_pairs * sizeof(struct fd_pair));
+ pair->user_data = malloc(sizeof(struct lttd_channel_data));
+ channel_data = pair->user_data;
+
+ strncpy(end_path_trace, relative_channel_path, PATH_MAX - path_trace_len);
+ printf_verbose("Creating trace file %s\n", path_trace);
- /* 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--;
- return 0; /* 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_verbose("Appending to file %s as requested\n",
path_trace);
- fd_pairs->pair[fd_pairs->num_pairs-1].trace =
- open(path_trace, O_WRONLY,
- S_IRWXU|S_IRWXG|S_IRWXO);
- if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) {
+ channel_data->trace = open(path_trace, O_WRONLY, S_IRWXU|S_IRWXG|S_IRWXO);
+ if(channel_data->trace == -1) {
perror(path_trace);
open_ret = -1;
- close(fd_pairs->pair[fd_pairs->num_pairs-1].channel);
- fd_pairs->num_pairs--;
goto end;
}
- ret = lseek(fd_pairs->pair[fd_pairs->num_pairs-1].trace,
- 0, SEEK_END);
+ ret = lseek(channel_data->trace, 0, SEEK_END);
if (ret < 0) {
perror(path_trace);
open_ret = -1;
- close(fd_pairs->pair[fd_pairs->num_pairs-1].channel);
- close(fd_pairs->pair[fd_pairs->num_pairs-1].trace);
- fd_pairs->num_pairs--;
+ close(channel_data->trace);
goto end;
}
} else {
printf("File %s exists, cannot open. Try append mode.\n", path_trace);
open_ret = -1;
- close(fd_pairs->pair[fd_pairs->num_pairs-1].channel);
- fd_pairs->num_pairs--;
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) {
+ channel_data->trace = open(path_trace, O_WRONLY|O_CREAT|O_EXCL, S_IRWXU|S_IRWXG|S_IRWXO);
+ if(channel_data->trace == -1) {
perror(path_trace);
open_ret = -1;
- close(fd_pairs->pair[fd_pairs->num_pairs-1].channel);
- fd_pairs->num_pairs--;
goto end;
}
}
}
+
end:
return open_ret;
+
}
-int open_channel_trace_pairs(char *subchannel_name, char *subtrace_name,
- struct channel_trace_fd *fd_pairs, int *inotify_fd,
- struct inotify_watch_array *iwatch_array)
+int lttd_on_close_channel(struct liblttd_callbacks *data, struct fd_pair *pair)
+{
+ int ret;
+ ret = close(((struct lttd_channel_data *)(pair->user_data))->trace);
+ free(pair->user_data);
+ return ret;
+}
+
+int lttd_on_new_channels_folder(struct liblttd_callbacks *data, char *relative_folder_path)
{
- 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;
- }
+ strncpy(end_path_trace, relative_folder_path, PATH_MAX - path_trace_len);
+ printf_verbose("Creating trace subdirectory %s\n", path_trace);
- printf_verbose("Creating trace subdirectory %s\n", subtrace_name);
- ret = mkdir(subtrace_name, S_IRWXU|S_IRWXG|S_IRWXO);
+ ret = mkdir(path_trace, S_IRWXU|S_IRWXG|S_IRWXO);
if(ret == -1) {
if(errno != EEXIST) {
- perror(subtrace_name);
+ perror(path_trace);
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;
-
-#ifdef HAS_INOTIFY
- iwatch_array->elem = realloc(iwatch_array->elem,
- ++iwatch_array->num * sizeof(struct inotify_watch));
-
- printf_verbose("Adding inotify for channel %s\n", path_channel);
- iwatch_array->elem[iwatch_array->num-1].wd = inotify_add_watch(*inotify_fd, path_channel, IN_CREATE);
- strcpy(iwatch_array->elem[iwatch_array->num-1].path_channel, path_channel);
- strcpy(iwatch_array->elem[iwatch_array->num-1].path_trace, path_trace);
- printf_verbose("Added inotify for channel %s, wd %u\n",
- iwatch_array->elem[iwatch_array->num-1].path_channel,
- iwatch_array->elem[iwatch_array->num-1].wd);
-#endif
-
- 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_verbose("Channel file : %s\n", path_channel);
-
- if(S_ISDIR(stat_buf.st_mode)) {
-
- printf_verbose("Entering channel subdirectory...\n");
- ret = open_channel_trace_pairs(path_channel, path_trace, fd_pairs,
- inotify_fd, iwatch_array);
- if(ret < 0) continue;
- } else if(S_ISREG(stat_buf.st_mode)) {
- open_ret = open_buffer_file(entry->d_name, path_channel, path_trace,
- fd_pairs);
- if(open_ret)
- goto end;
- }
- }
-
end:
- closedir(channel_dir);
-
return open_ret;
}
-
-int read_subbuffer(struct fd_pair *pair)
+int lttd_on_read_subbuffer(struct liblttd_callbacks *data, struct fd_pair *pair, unsigned int len)
{
- unsigned int consumed_old, len;
- int err;
long ret;
- off_t offset;
-
+ off_t offset = 0;
- err = ioctl(pair->channel, RELAY_GET_SB, &consumed_old);
- printf_verbose("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;
- }
-#if 0
- 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;
- }
-#endif //0
- err = ioctl(pair->channel, RELAY_GET_SB_SIZE, &len);
- if(err != 0) {
- ret = errno;
- perror("Getting sub-buffer len failed.");
- goto get_error;
- }
-
- offset = 0;
while (len > 0) {
printf_verbose("splice chan to pipe offset %lu\n",
(unsigned long)offset);
perror("Error in relay splice");
goto write_error;
}
- ret = splice(thread_pipe[0], NULL, pair->trace, NULL,
- ret, SPLICE_F_MOVE | SPLICE_F_MORE);
+ ret = splice(thread_pipe[0], NULL,
+ ((struct lttd_channel_data *)(pair->user_data))->trace,
+ NULL, ret, SPLICE_F_MOVE | SPLICE_F_MORE);
printf_verbose("splice pipe to file %ld\n", ret);
if (ret < 0) {
perror("Error in file splice");
len -= ret;
}
-#if 0
- err = fsync(pair->trace);
- if(err < 0) {
- ret = errno;
- perror("Error in writing to file");
- goto write_error;
- }
-#endif //0
write_error:
- ret = 0;
- err = ioctl(pair->channel, RELAY_PUT_SB, &consumed_old);
- if(err != 0) {
- ret = errno;
- if(errno == EFAULT) {
- perror("Error in unreserving sub buffer\n");
- } else if(errno == EIO) {
- /* Should never happen with newer LTTng versions */
- perror("Reader has been pushed by the writer, last sub-buffer corrupted.");
- }
- goto get_error;
- }
-
-get_error:
- return ret;
-}
-
-
-int map_channels(struct channel_trace_fd *fd_pairs,
- int idx_begin, int idx_end)
-{
- 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=idx_begin;i<idx_end;i++) {
- struct fd_pair *pair = &fd_pairs->pair[i];
-
- ret = ioctl(pair->channel, RELAY_GET_N_SB, &pair->n_sb);
- if(ret != 0) {
- perror("Error in getting the number of sub-buffers");
- goto end;
- }
- ret = ioctl(pair->channel, RELAY_GET_MAX_SB_SIZE,
- &pair->max_sb_size);
- if(ret != 0) {
- perror("Error in getting the max sub-buffer size");
- goto end;
- }
- ret = pthread_mutex_init(&pair->mutex, NULL); /* Fast mutex */
- if(ret != 0) {
- perror("Error in mutex init");
- goto end;
- }
- }
-
-#if 0
- /* Mmap each FD */
- for(i=idx_begin;i<idx_end;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=idx_begin;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;
- }
-
-#endif //0
-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;
-
-#if 0
- err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs);
- if(err_ret != 0) {
- perror("Error in munmap");
- }
- ret |= err_ret;
-#endif //0
- err_ret = pthread_mutex_destroy(&pair->mutex);
- if(err_ret != 0) {
- perror("Error in mutex destroy");
- }
- ret |= err_ret;
- }
-
- return ret;
-}
-
-#ifdef HAS_INOTIFY
-/* Inotify event arrived.
- *
- * Only support add file for now.
- */
-
-int read_inotify(int inotify_fd,
- struct channel_trace_fd *fd_pairs,
- struct inotify_watch_array *iwatch_array)
-{
- char buf[sizeof(struct inotify_event) + PATH_MAX];
- char path_channel[PATH_MAX];
- char path_trace[PATH_MAX];
- ssize_t len;
- struct inotify_event *ievent;
- size_t offset;
- unsigned int i;
- int ret;
- int old_num;
-
- offset = 0;
- len = read(inotify_fd, buf, sizeof(struct inotify_event) + PATH_MAX);
- if(len < 0) {
-
- if(errno == EAGAIN)
- return 0; /* another thread got the data before us */
-
- printf("Error in read from inotify FD %s.\n", strerror(len));
- return -1;
- }
- while(offset < len) {
- ievent = (struct inotify_event *)&(buf[offset]);
- for(i=0; i<iwatch_array->num; i++) {
- if(iwatch_array->elem[i].wd == ievent->wd &&
- ievent->mask == IN_CREATE) {
- printf_verbose(
- "inotify wd %u event mask : %u for %s%s\n",
- ievent->wd, ievent->mask,
- iwatch_array->elem[i].path_channel,
- ievent->name);
- old_num = fd_pairs->num_pairs;
- strcpy(path_channel, iwatch_array->elem[i].path_channel);
- strcat(path_channel, ievent->name);
- strcpy(path_trace, iwatch_array->elem[i].path_trace);
- strcat(path_trace, ievent->name);
- if(ret = open_buffer_file(ievent->name, path_channel,
- path_trace, fd_pairs)) {
- printf("Error opening buffer file\n");
- return -1;
- }
- if(ret = map_channels(fd_pairs, old_num, fd_pairs->num_pairs)) {
- printf("Error mapping channel\n");
- return -1;
- }
-
- }
- }
- offset += sizeof(*ievent) + ievent->len;
- }
-}
-#endif //HAS_INOTIFY
-
-/* read_channels
- *
- * Thread worker.
- *
- * Read the debugfs channels and write them in the paired tracefiles.
- *
- * @fd_pairs : paired channels and trace files.
- *
- * returns 0 on success, -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.
- */
-
-int read_channels(unsigned long thread_num, struct channel_trace_fd *fd_pairs,
- int inotify_fd, struct inotify_watch_array *iwatch_array)
-{
- struct pollfd *pollfd = NULL;
- int num_pollfd;
- int i,j;
- int num_rdy, num_hup;
- int high_prio;
- int ret = 0;
- int inotify_fds;
- unsigned int old_num;
-
-#ifdef HAS_INOTIFY
- inotify_fds = 1;
-#else
- inotify_fds = 0;
-#endif
-
- pthread_rwlock_rdlock(&fd_pairs_lock);
-
- /* Start polling the FD. Keep one fd for inotify */
- pollfd = malloc((inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd));
-
-#ifdef HAS_INOTIFY
- pollfd[0].fd = inotify_fd;
- pollfd[0].events = POLLIN|POLLPRI;
-#endif
-
- for(i=0;i<fd_pairs->num_pairs;i++) {
- pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel;
- pollfd[inotify_fds+i].events = POLLIN|POLLPRI;
- }
- num_pollfd = inotify_fds + fd_pairs->num_pairs;
-
-
- pthread_rwlock_unlock(&fd_pairs_lock);
-
- 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", num_pollfd);
-#endif //DEBUG
-
- /* Have we received a signal ? */
- if(quit_program) break;
-
- num_rdy = poll(pollfd, num_pollfd, -1);
-
- if(num_rdy == -1) {
- perror("Poll error");
- goto free_fd;
- }
-
- printf_verbose("Data received\n");
-#ifdef HAS_INOTIFY
- switch(pollfd[0].revents) {
- case POLLERR:
- printf_verbose(
- "Error returned in polling inotify fd %d.\n",
- pollfd[0].fd);
- break;
- case POLLHUP:
- printf_verbose(
- "Polling inotify fd %d tells it has hung up.\n",
- pollfd[0].fd);
- break;
- case POLLNVAL:
- printf_verbose(
- "Polling inotify fd %d tells fd is not open.\n",
- pollfd[0].fd);
- break;
- case POLLPRI:
- case POLLIN:
- printf_verbose(
- "Polling inotify fd %d : data ready.\n",
- pollfd[0].fd);
-
- pthread_rwlock_wrlock(&fd_pairs_lock);
- read_inotify(inotify_fd, fd_pairs, iwatch_array);
- pthread_rwlock_unlock(&fd_pairs_lock);
-
- break;
- }
-#endif
-
- for(i=inotify_fds;i<num_pollfd;i++) {
- switch(pollfd[i].revents) {
- case POLLERR:
- printf_verbose(
- "Error returned in polling fd %d.\n",
- pollfd[i].fd);
- num_hup++;
- break;
- case POLLHUP:
- printf_verbose(
- "Polling fd %d tells it has hung up.\n",
- pollfd[i].fd);
- num_hup++;
- break;
- case POLLNVAL:
- printf_verbose(
- "Polling fd %d tells fd is not open.\n",
- pollfd[i].fd);
- num_hup++;
- break;
- case POLLPRI:
- pthread_rwlock_rdlock(&fd_pairs_lock);
- if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) {
- printf_verbose(
- "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 sub-buffer */
- ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]);
- if(ret == EAGAIN) ret = 0;
-
- ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex);
- if(ret)
- printf("Error in mutex unlock : %s\n", strerror(ret));
- }
- pthread_rwlock_unlock(&fd_pairs_lock);
- break;
- }
- }
- /* If every buffer FD has hung up, we end the read loop here */
- if(num_hup == num_pollfd - inotify_fds) break;
-
- if(!high_prio) {
- for(i=inotify_fds;i<num_pollfd;i++) {
- switch(pollfd[i].revents) {
- case POLLIN:
- pthread_rwlock_rdlock(&fd_pairs_lock);
- if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) {
- /* Take care of low priority channels. */
- printf_verbose(
- "Normal read on fd %d\n",
- pollfd[i].fd);
- /* it's ok to have an unavailable subbuffer */
- ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]);
- if(ret == EAGAIN) ret = 0;
-
- ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex);
- if(ret)
- printf("Error in mutex unlock : %s\n", strerror(ret));
- }
- pthread_rwlock_unlock(&fd_pairs_lock);
- break;
- }
- }
- }
-
- /* Update pollfd array if an entry was added to fd_pairs */
- pthread_rwlock_rdlock(&fd_pairs_lock);
- if((inotify_fds + fd_pairs->num_pairs) != num_pollfd) {
- pollfd = realloc(pollfd,
- (inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd));
- for(i=num_pollfd-inotify_fds;i<fd_pairs->num_pairs;i++) {
- pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel;
- pollfd[inotify_fds+i].events = POLLIN|POLLPRI;
- }
- num_pollfd = fd_pairs->num_pairs + inotify_fds;
- }
- pthread_rwlock_unlock(&fd_pairs_lock);
-
- /* NB: If the fd_pairs structure is updated by another thread from this
- * point forward, the current thread will wait in the poll without
- * monitoring the new channel. However, this thread will add the
- * new channel on next poll (and this should not take too much time
- * on a loaded system).
- *
- * This event is quite unlikely and can only occur if a CPU is
- * hot-plugged while multple lttd threads are running.
- */
- }
-
-free_fd:
- free(pollfd);
-
-end:
- return ret;
-}
-
-
-void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs, int inotify_fd,
- struct inotify_watch_array *iwatch_array)
-{
- int i;
+int on_new_thread(struct liblttd_callbacks *data, unsigned long thread_num) {
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);
- free(iwatch_array->elem);
-}
-
-/* Thread worker */
-void * thread_main(void *arg)
-{
- long ret;
- unsigned long thread_num = (unsigned long)arg;
-
ret = pipe(thread_pipe);
if (ret < 0) {
perror("Error creating pipe");
- return (void*)ret;
+ return ret;
}
- ret = read_channels(thread_num, &fd_pairs, inotify_fd, &inotify_watch_array);
- close(thread_pipe[0]); /* close read end */
- close(thread_pipe[1]); /* close write end */
- return (void*)ret;
+ return 0;
}
-
-int channels_init()
-{
- int ret = 0;
-
- inotify_fd = inotify_init();
- fcntl(inotify_fd, F_SETFL, O_NONBLOCK);
-
- if(ret = open_channel_trace_pairs(channel_name, trace_name, &fd_pairs,
- &inotify_fd, &inotify_watch_array))
- goto close_channel;
- if (fd_pairs.num_pairs == 0) {
- printf("No channel available for reading, exiting\n");
- ret = -ENOENT;
- goto close_channel;
- }
- if(ret = map_channels(&fd_pairs, 0, fd_pairs.num_pairs))
- goto close_channel;
+int on_close_thread(struct liblttd_callbacks *data, unsigned long thread_num) {
+ close(thread_pipe[0]); /* close read end */
+ close(thread_pipe[1]); /* close write end */
return 0;
-
-close_channel:
- close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array);
- if(inotify_fd >= 0)
- close(inotify_fd);
- return ret;
}
-
int main(int argc, char ** argv)
{
int ret = 0;
struct sigaction act;
- pthread_t *tids;
- unsigned long i;
- void *tret;
-
+
+ struct liblttd_callbacks callbacks = {
+ lttd_on_open_channel,
+ lttd_on_close_channel,
+ lttd_on_new_channels_folder,
+ lttd_on_read_subbuffer,
+ NULL,
+ on_new_thread,
+ on_close_thread,
+ NULL
+ };
+
ret = parse_arguments(argc, argv);
if(ret != 0) show_arguments();
sigaction(SIGQUIT, &act, NULL);
sigaction(SIGINT, &act, NULL);
- if(ret = channels_init())
- return ret;
-
if(daemon_mode) {
ret = daemon(0, 0);
}
}
- tids = malloc(sizeof(pthread_t) * num_threads);
- for(i=0; i<num_threads; i++) {
-
- ret = pthread_create(&tids[i], NULL, thread_main, (void*)i);
- if(ret) {
- perror("Error creating thread");
- break;
- }
- }
+ strncpy(path_trace, trace_name, PATH_MAX-1);
+ path_trace_len = strlen(path_trace);
+ end_path_trace = path_trace + path_trace_len;
- for(i=0; i<num_threads; i++) {
- ret = pthread_join(tids[i], &tret);
- if(ret) {
- perror("Error joining thread");
- break;
- }
- if((long)tret != 0) {
- printf("Error %s occured in thread %u\n",
- strerror((long)tret), i);
- }
- }
+ liblttd_start(channel_name, num_threads, dump_flight_only, dump_normal_only,
+ verbose_mode, &callbacks);
- free(tids);
- ret = unmap_channels(&fd_pairs);
- close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array);
- if(inotify_fd >= 0)
- close(inotify_fd);
-
return ret;
}
+
projects / ltt-control.git / commitdiff
