#include <urcu/list.h>
#include <poll.h>
#include <unistd.h>
+#include <sys/mman.h>
#include "lttngerr.h"
#include "libkernelctl.h"
#include "liblttsessiondcomm.h"
-#include "kconsumerd.h"
-
-/* Init the list of FDs */
-static struct ltt_kconsumerd_fd_list kconsumerd_fd_list = {
- .head = CDS_LIST_HEAD_INIT(kconsumerd_fd_list.head),
-};
-
-/* Number of element for the list below. */
-static unsigned int fds_count;
-
-/* If the local array of FDs needs update in the poll function */
-static unsigned int update_fd_array = 1;
-
-/* lock the fd array and structures */
-static pthread_mutex_t kconsumerd_lock_fds;
+#include "liblttkconsumerd.h"
/* the two threads (receive fd and poll) */
-static pthread_t threads[2];
+pthread_t threads[2];
-/* communication with splice */
-static int thread_pipe[2];
-
-/* socket to communicate errors with sessiond */
-static int error_socket = -1;
+/* to count the number of time the user pressed ctrl+c */
+static int sigintcount = 0;
/* Argument variables */
int opt_quiet;
int opt_verbose;
static int opt_daemon;
static const char *progname;
-static char command_sock_path[PATH_MAX]; /* Global command socket path */
-static char error_sock_path[PATH_MAX]; /* Global error path */
-
-/*
- * cleanup
- *
- * Cleanup the daemon's socket on exit
- */
-static void cleanup()
-{
- unlink(command_sock_path);
-}
-
-/* send_error
- *
- * send return code to ltt-sessiond
- */
-static int send_error(enum lttcomm_return_code cmd)
-{
- if (error_socket > 0) {
- return lttcomm_send_unix_sock(error_socket, &cmd,
- sizeof(enum lttcomm_sessiond_command));
- } else {
- return 0;
- }
-}
-
-/*
- * cleanup_kconsumerd_fd
- *
- * Close the FDs and frees a ltt_kconsumerd_fd struct
- */
-static void cleanup_kconsumerd_fd(struct ltt_kconsumerd_fd *lcf)
-{
- if (lcf != NULL) {
- close(lcf->out_fd);
- close(lcf->consumerd_fd);
- free(lcf);
- lcf = NULL;
- }
-}
-
-/*
- * add_fd
- *
- * Add a fd to the global list protected by a mutex
- */
-static int add_fd(struct lttcomm_kconsumerd_msg *buf, int consumerd_fd)
-{
- struct ltt_kconsumerd_fd *tmp_fd;
- int ret;
-
- tmp_fd = malloc(sizeof(struct ltt_kconsumerd_fd));
- tmp_fd->sessiond_fd = buf->fd;
- tmp_fd->consumerd_fd = consumerd_fd;
- tmp_fd->state = buf->state;
- tmp_fd->max_sb_size = buf->max_sb_size;
- strncpy(tmp_fd->path_name, buf->path_name, PATH_MAX);
-
- /* Opening the tracefile in write mode */
- DBG("Opening %s for writing", tmp_fd->path_name);
- ret = open(tmp_fd->path_name,
- O_WRONLY|O_CREAT, S_IRWXU|S_IRWXG|S_IRWXO);
- if (ret < 0) {
- ERR("Opening %s", tmp_fd->path_name);
- perror("open");
- goto end;
- }
- tmp_fd->out_fd = ret;
- tmp_fd->out_fd_offset = 0;
-
- DBG("Adding %s (%d, %d, %d)", tmp_fd->path_name,
- tmp_fd->sessiond_fd, tmp_fd->consumerd_fd, tmp_fd->out_fd);
-
- pthread_mutex_lock(&kconsumerd_lock_fds);
- cds_list_add(&tmp_fd->list, &kconsumerd_fd_list.head);
- fds_count++;
- pthread_mutex_unlock(&kconsumerd_lock_fds);
-
-end:
- return ret;
-}
-
-/*
- * del_fd
- *
- * Remove a fd from the global list protected by a mutex
- */
-static void del_fd(struct ltt_kconsumerd_fd *lcf)
-{
- pthread_mutex_lock(&kconsumerd_lock_fds);
- cds_list_del(&lcf->list);
- if (fds_count > 0) {
- fds_count--;
- DBG("Removed ltt_kconsumerd_fd");
- cleanup_kconsumerd_fd(lcf);
- }
- pthread_mutex_unlock(&kconsumerd_lock_fds);
-}
-
-/*
- * close_outfds
- *
- * Close all fds in the previous fd_list
- * Must be used with kconsumerd_lock_fds lock held
- */
-static void close_outfds()
-{
- struct ltt_kconsumerd_fd *iter;
- cds_list_for_each_entry(iter, &kconsumerd_fd_list.head, list) {
- del_fd(iter);
- }
-}
+char command_sock_path[PATH_MAX]; /* Global command socket path */
+char error_sock_path[PATH_MAX]; /* Global error path */
/*
* sighandler
*/
static void sighandler(int sig)
{
- /* unblock the threads */
- pthread_cancel(threads[0]);
- pthread_cancel(threads[1]);
-
- close_outfds();
- cleanup();
+ if (sig == SIGINT && sigintcount++ == 0) {
+ DBG("ignoring first SIGINT");
+ return;
+ }
- return;
+ kconsumerd_cleanup();
}
/*
return ret;
}
-/*
- * on_read_subbuffer
- *
- * Splice the data from the ring buffer to the tracefile.
- * Returns the number of bytes spliced
- */
-static int on_read_subbuffer(struct ltt_kconsumerd_fd *kconsumerd_fd,
- unsigned long len)
-{
- long ret = 0;
- loff_t offset = 0;
- off_t orig_offset = kconsumerd_fd->out_fd_offset;
- int fd = kconsumerd_fd->consumerd_fd;
- int outfd = kconsumerd_fd->out_fd;
-
- while (len > 0) {
- DBG("splice chan to pipe offset %lu (fd : %d)",
- (unsigned long)offset, fd);
- ret = splice(fd, &offset, thread_pipe[1], NULL, len,
- SPLICE_F_MOVE | SPLICE_F_MORE);
- DBG("splice chan to pipe ret %ld", ret);
- if (ret < 0) {
- ret = errno;
- perror("Error in relay splice");
- goto splice_error;
- }
-
- ret = splice(thread_pipe[0], NULL, outfd, NULL, ret,
- SPLICE_F_MOVE | SPLICE_F_MORE);
- DBG("splice pipe to file %ld", ret);
- if (ret < 0) {
- ret = errno;
- perror("Error in file splice");
- goto splice_error;
- }
- if (ret >= len) {
- len = 0;
- }
- /* This won't block, but will start writeout asynchronously */
- sync_file_range(outfd, kconsumerd_fd->out_fd_offset, ret,
- SYNC_FILE_RANGE_WRITE);
- kconsumerd_fd->out_fd_offset += ret;
- }
-
- /*
- * This does a blocking write-and-wait on any page that belongs to the
- * subbuffer prior to the one we just wrote.
- * Don't care about error values, as these are just hints and ways to
- * limit the amount of page cache used.
- */
- if (orig_offset >= kconsumerd_fd->max_sb_size) {
- sync_file_range(outfd, orig_offset - kconsumerd_fd->max_sb_size,
- kconsumerd_fd->max_sb_size,
- SYNC_FILE_RANGE_WAIT_BEFORE
- | SYNC_FILE_RANGE_WRITE
- | SYNC_FILE_RANGE_WAIT_AFTER);
- /*
- * Give hints to the kernel about how we access the file:
- * POSIX_FADV_DONTNEED : we won't re-access data in a near
- * future after we write it.
- * We need to call fadvise again after the file grows because
- * the kernel does not seem to apply fadvise to non-existing
- * parts of the file.
- * Call fadvise _after_ having waited for the page writeback to
- * complete because the dirty page writeback semantic is not
- * well defined. So it can be expected to lead to lower
- * throughput in streaming.
- */
- posix_fadvise(outfd, orig_offset - kconsumerd_fd->max_sb_size,
- kconsumerd_fd->max_sb_size, POSIX_FADV_DONTNEED);
- }
- goto end;
-
-splice_error:
- /* send the appropriate error description to sessiond */
- switch(ret) {
- case EBADF:
- send_error(KCONSUMERD_SPLICE_EBADF);
- break;
- case EINVAL:
- send_error(KCONSUMERD_SPLICE_EINVAL);
- break;
- case ENOMEM:
- send_error(KCONSUMERD_SPLICE_ENOMEM);
- break;
- case ESPIPE:
- send_error(KCONSUMERD_SPLICE_ESPIPE);
- break;
- }
-
-end:
- return ret;
-}
-
-/*
- * read_subbuffer
- *
- * Consume data on a file descriptor and write it on a trace file
- */
-static int read_subbuffer(struct ltt_kconsumerd_fd *kconsumerd_fd)
-{
- unsigned long len;
- int err;
- long ret = 0;
- int infd = kconsumerd_fd->consumerd_fd;
-
- DBG("In read_subbuffer");
- /* Get the next subbuffer */
- err = kernctl_get_next_subbuf(infd);
- if (err != 0) {
- ret = errno;
- perror("Reserving sub buffer failed (everything is normal, "
- "it is due to concurrency)");
- goto end;
- }
-
- /* read the whole subbuffer */
- err = kernctl_get_padded_subbuf_size(infd, &len);
- if (err != 0) {
- ret = errno;
- perror("Getting sub-buffer len failed.");
- goto end;
- }
-
- /* splice the subbuffer to the tracefile */
- ret = on_read_subbuffer(kconsumerd_fd, len);
- if (ret < 0) {
- /*
- * display the error but continue processing to try
- * to release the subbuffer
- */
- ERR("Error splicing to tracefile");
- }
-
- err = kernctl_put_next_subbuf(infd);
- 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 end;
- }
-
-end:
- return ret;
-}
-
-/*
- * change_fd_state
- *
- * Update a fd according to what we just received
- */
-static void change_fd_state(int sessiond_fd,
- enum lttcomm_kconsumerd_fd_state state)
-{
- struct ltt_kconsumerd_fd *iter;
- cds_list_for_each_entry(iter, &kconsumerd_fd_list.head, list) {
- if (iter->sessiond_fd == sessiond_fd) {
- iter->state = state;
- break;
- }
- }
-}
-
-/*
- * consumerd_recv_fd
- *
- * Receives an array of file descriptors and the associated
- * structures describing each fd (path name).
- * Returns the size of received data
- */
-static int consumerd_recv_fd(int sfd, int size,
- enum lttcomm_consumerd_command cmd_type)
-{
- struct msghdr msg;
- struct iovec iov[1];
- int ret, i;
- struct cmsghdr *cmsg;
- int nb_fd;
- char tmp[CMSG_SPACE(size)];
- struct lttcomm_kconsumerd_msg *buf;
- /* the number of fds we are about to receive */
- nb_fd = size/sizeof(struct lttcomm_kconsumerd_msg);
-
- buf = malloc(size);
-
- memset(&msg, 0, sizeof(msg));
-
- /* Prepare to receive the structures */
- iov[0].iov_base = buf;
- iov[0].iov_len = size;
- msg.msg_iov = iov;
- msg.msg_iovlen = 1;
-
- msg.msg_control = tmp;
- msg.msg_controllen = sizeof(tmp);
-
- DBG("Waiting to receive fds");
- if ((ret = recvmsg(sfd, &msg, 0)) < 0) {
- perror("recvmsg");
- }
- if (ret != size) {
- ERR("Received only %d, expected %d", ret, size);
- send_error(KCONSUMERD_ERROR_RECV_FD);
- goto end;
- }
-
- cmsg = CMSG_FIRSTHDR(&msg);
- if (!cmsg) {
- ERR("Invalid control message header");
- ret = -1;
- send_error(KCONSUMERD_ERROR_RECV_FD);
- goto end;
- }
-
- /* if we received fds */
- if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
- DBG("Receive : expecting %d fds", nb_fd);
- for (i = 0; i < nb_fd; i++) {
- switch (cmd_type) {
- case LTTCOMM_ADD_STREAM:
- DBG("add_fd %s (%d)", buf[i].path_name, ((int *)CMSG_DATA(cmsg))[i]);
- ret = add_fd(&buf[i], ((int *)CMSG_DATA(cmsg))[i]);
- if (ret < 0) {
- send_error(KCONSUMERD_OUTFD_ERROR);
- goto end;
- }
- break;
- case LTTCOMM_UPDATE_STREAM:
- change_fd_state(buf[i].fd, buf[i].state);
- break;
- default:
- break;
- }
- }
- /* flag to tell the polling thread to update its fd array */
- update_fd_array = 1;
- send_error(KCONSUMERD_SUCCESS_RECV_FD);
- } else {
- ERR("Didn't received any fd");
- send_error(KCONSUMERD_ERROR_RECV_FD);
- ret = -1;
- goto end;
- }
-
-end:
- if (buf != NULL) {
- free(buf);
- buf = NULL;
- }
- return ret;
-}
-
-/*
- * thread_receive_fds
- *
- * This thread listens on the consumerd socket and
- * receives the file descriptors from ltt-sessiond
- */
-static void *thread_receive_fds(void *data)
-{
- int sock, client_socket, ret;
- struct lttcomm_kconsumerd_header tmp;
-
- DBG("Creating command socket %s", command_sock_path);
- unlink(command_sock_path);
- client_socket = lttcomm_create_unix_sock(command_sock_path);
- if (client_socket < 0) {
- ERR("Cannot create command socket");
- goto error;
- }
-
- ret = lttcomm_listen_unix_sock(client_socket);
- if (ret < 0) {
- goto error;
- }
-
- DBG("Sending ready command to ltt-sessiond");
- ret = send_error(KCONSUMERD_COMMAND_SOCK_READY);
- if (ret < 0) {
- ERR("Error sending ready command to ltt-sessiond");
- goto error;
- }
-
- while (1) {
- /* Blocking call, waiting for transmission */
- sock = lttcomm_accept_unix_sock(client_socket);
- if (sock <= 0) {
- continue;
- }
-
- /* We first get the number of fd we are about to receive */
- ret = lttcomm_recv_unix_sock(sock, &tmp,
- sizeof(struct lttcomm_kconsumerd_header));
- if (ret < 0) {
- ERR("Receiving the lttcomm_kconsumerd_header");
- continue;
- }
- ret = consumerd_recv_fd(sock, tmp.payload_size, tmp.cmd_type);
- if (ret < 0) {
- continue;
- }
- }
-
-error:
- return NULL;
-}
-
-/*
- * update_poll_array
- *
- * Allocate the pollfd structure and the local view of the out fds
- * to avoid doing a lookup in the linked list and concurrency issues
- * when writing is needed.
- * Returns the number of fds in the structures
- */
-static int update_poll_array(struct pollfd **pollfd,
- struct ltt_kconsumerd_fd **local_kconsumerd_fd)
-{
- struct ltt_kconsumerd_fd *iter;
- int i = 0;
-
- if (*pollfd != NULL) {
- free(*pollfd);
- *pollfd = NULL;
- }
-
- if (*local_kconsumerd_fd != NULL) {
- free(*local_kconsumerd_fd);
- *local_kconsumerd_fd = NULL;
- }
-
- *pollfd = malloc(fds_count * sizeof(struct pollfd));
- if (*pollfd == NULL) {
- perror("pollfd malloc");
- goto error_mem;
- }
-
- *local_kconsumerd_fd = malloc(fds_count * sizeof(struct ltt_kconsumerd_fd));
- if (*local_kconsumerd_fd == NULL) {
- perror("local_kconsumerd_fd malloc");
- goto error_mem;
- }
-
- DBG("Updating poll fd array");
- pthread_mutex_lock(&kconsumerd_lock_fds);
-
- cds_list_for_each_entry(iter, &kconsumerd_fd_list.head, list) {
- DBG("Inside for each");
- if (iter->state == ACTIVE_FD) {
- DBG("Active FD %d", iter->consumerd_fd);
- pollfd[i]->fd = iter->consumerd_fd;
- pollfd[i]->events = POLLIN | POLLPRI;
- local_kconsumerd_fd[i] = iter;
- i++;
- } else if (iter->state == DELETE_FD) {
- del_fd(iter);
- }
- }
- update_fd_array = 0;
- pthread_mutex_unlock(&kconsumerd_lock_fds);
- return i;
-
-error_mem:
- return -ENOMEM;
-}
-
-/*
- * thread_poll_fds
- *
- * This thread polls the fds in the ltt_fd_list to consume the data
- * and write it to tracefile if necessary.
- */
-static void *thread_poll_fds(void *data)
-{
- int num_rdy, num_hup, high_prio, ret, i;
- struct pollfd *pollfd = NULL;
- /* local view of the fds */
- struct ltt_kconsumerd_fd *local_kconsumerd_fd = NULL;
- /* local view of fds_count */
- int nb_fd = 0;
-
- ret = pipe(thread_pipe);
- if (ret < 0) {
- perror("Error creating pipe");
- goto end;
- }
-
- while (1) {
- high_prio = 0;
- num_hup = 0;
-
- /*
- * the ltt_fd_list has been updated, we need to update our
- * local array as well
- */
- if (update_fd_array) {
- ret = update_poll_array(&pollfd, &local_kconsumerd_fd);
- if (ret < 0) {
- ERR("Error in allocating pollfd or local_outfds");
- send_error(KCONSUMERD_POLL_ERROR);
- goto end;
- }
- nb_fd = ret;
- }
-
- /* poll on the array of fds */
- DBG("polling on %d fd", nb_fd);
- num_rdy = poll(pollfd, nb_fd, POLL_TIMEOUT);
- DBG("poll num_rdy : %d", num_rdy);
- if (num_rdy == -1) {
- perror("Poll error");
- send_error(KCONSUMERD_POLL_ERROR);
- goto end;
- }
-
- /* Take care of high priority channels first. */
- for (i = 0; i < nb_fd; i++) {
- switch(pollfd[i].revents) {
- case POLLERR:
- ERR("Error returned in polling fd %d.", pollfd[i].fd);
- num_hup++;
- send_error(KCONSUMERD_POLL_ERROR);
- break;
- case POLLHUP:
- ERR("Polling fd %d tells it has hung up.", pollfd[i].fd);
- num_hup++;
- break;
- case POLLNVAL:
- ERR("Polling fd %d tells fd is not open.", pollfd[i].fd);
- send_error(KCONSUMERD_POLL_NVAL);
- num_hup++;
- break;
- case POLLPRI:
- DBG("Urgent read on fd %d", pollfd[i].fd);
- high_prio = 1;
- ret = read_subbuffer(&local_kconsumerd_fd[i]);
- /* it's ok to have an unavailable sub-buffer (FIXME : is it ?) */
- if (ret == EAGAIN) {
- ret = 0;
- }
- break;
- }
- }
-
- /* If every buffer FD has hung up, we end the read loop here */
- if (nb_fd > 0 && num_hup == nb_fd) {
- DBG("every buffer FD has hung up\n");
- send_error(KCONSUMERD_POLL_HUP);
- continue;
- }
-
- /* Take care of low priority channels. */
- if (!high_prio) {
- for (i = 0; i < nb_fd; i++) {
- switch(pollfd[i].revents) {
- case POLLIN:
- DBG("Normal read on fd %d", pollfd[i].fd);
- ret = read_subbuffer(&local_kconsumerd_fd[i]);
- /* it's ok to have an unavailable subbuffer (FIXME : is it ?) */
- if (ret == EAGAIN) {
- ret = 0;
- }
- break;
- }
- }
- }
- }
-end:
- if (pollfd != NULL) {
- free(pollfd);
- pollfd = NULL;
- }
- if (local_kconsumerd_fd != NULL) {
- free(local_kconsumerd_fd);
- local_kconsumerd_fd = NULL;
- }
- return NULL;
-}
-
/*
* usage function on stderr
*/
}
switch (c) {
- case 0:
- fprintf(stderr, "option %s", long_options[option_index].name);
- if (optarg) {
- fprintf(stderr, " with arg %s\n", optarg);
- }
- break;
- case 'c':
- snprintf(command_sock_path, PATH_MAX, "%s", optarg);
- break;
- case 'e':
- snprintf(error_sock_path, PATH_MAX, "%s", optarg);
- break;
- case 'd':
- opt_daemon = 1;
- break;
- case 'h':
- usage();
- exit(EXIT_FAILURE);
- case 'q':
- opt_quiet = 1;
- break;
- case 'v':
- opt_verbose = 1;
- break;
- case 'V':
- fprintf(stdout, "%s\n", VERSION);
- exit(EXIT_SUCCESS);
- default:
- usage();
- exit(EXIT_FAILURE);
+ case 0:
+ fprintf(stderr, "option %s", long_options[option_index].name);
+ if (optarg) {
+ fprintf(stderr, " with arg %s\n", optarg);
+ }
+ break;
+ case 'c':
+ snprintf(command_sock_path, PATH_MAX, "%s", optarg);
+ break;
+ case 'e':
+ snprintf(error_sock_path, PATH_MAX, "%s", optarg);
+ break;
+ case 'd':
+ opt_daemon = 1;
+ break;
+ case 'h':
+ usage();
+ exit(EXIT_FAILURE);
+ case 'q':
+ opt_quiet = 1;
+ break;
+ case 'v':
+ opt_verbose = 1;
+ break;
+ case 'V':
+ fprintf(stdout, "%s\n", VERSION);
+ exit(EXIT_SUCCESS);
+ default:
+ usage();
+ exit(EXIT_FAILURE);
}
}
}
snprintf(command_sock_path, PATH_MAX,
KCONSUMERD_CMD_SOCK_PATH);
}
+ kconsumerd_set_command_socket_path(command_sock_path);
if (strlen(error_sock_path) == 0) {
snprintf(error_sock_path, PATH_MAX,
KCONSUMERD_ERR_SOCK_PATH);
goto error;
}
+ /* create the pipe to wake to polling thread when needed */
+ ret = kconsumerd_create_poll_pipe();
+ if (ret < 0) {
+ perror("Error creating poll pipe");
+ goto end;
+ }
+
/* Connect to the socket created by ltt-sessiond to report errors */
DBG("Connecting to error socket %s", error_sock_path);
- error_socket = lttcomm_connect_unix_sock(error_sock_path);
+ ret = lttcomm_connect_unix_sock(error_sock_path);
/* not a fatal error, but all communication with ltt-sessiond will fail */
- if (error_socket < 0) {
+ if (ret < 0) {
WARN("Cannot connect to error socket, is ltt-sessiond started ?");
}
+ kconsumerd_set_error_socket(ret);
/* Create the thread to manage the receive of fd */
- ret = pthread_create(&threads[0], NULL, thread_receive_fds, (void *) NULL);
+ ret = pthread_create(&threads[0], NULL, kconsumerd_thread_receive_fds,
+ (void *) NULL);
if (ret != 0) {
perror("pthread_create");
goto error;
}
/* Create thread to manage the polling/writing of traces */
- ret = pthread_create(&threads[1], NULL, thread_poll_fds, (void *) NULL);
+ ret = pthread_create(&threads[1], NULL, kconsumerd_thread_poll_fds,
+ (void *) NULL);
if (ret != 0) {
perror("pthread_create");
goto error;
}
}
ret = EXIT_SUCCESS;
- send_error(KCONSUMERD_EXIT_SUCCESS);
+ kconsumerd_send_error(KCONSUMERD_EXIT_SUCCESS);
goto end;
error:
ret = EXIT_FAILURE;
- send_error(KCONSUMERD_EXIT_FAILURE);
+ kconsumerd_send_error(KCONSUMERD_EXIT_FAILURE);
end:
- cleanup();
+ kconsumerd_cleanup();
return ret;
}
projects / lttng-tools.git / blobdiff