X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=liblttkconsumerd%2Fliblttkconsumerd.c;h=9ad380c8dab5e8c1be679a0881890e929f355c57;hp=5735f38b818dcea54a15c08c93ab357ec309a8ac;hb=ca3c5ac0cf100d80352a1a81936b5adc47942f35;hpb=82a3637f639486c07ff937ab03e1e9532379d26a diff --git a/liblttkconsumerd/liblttkconsumerd.c b/liblttkconsumerd/liblttkconsumerd.c index 5735f38b8..9ad380c8d 100644 --- a/liblttkconsumerd/liblttkconsumerd.c +++ b/liblttkconsumerd/liblttkconsumerd.c @@ -28,6 +28,7 @@ #include #include #include +#include #include "libkernelctl.h" #include "liblttkconsumerd.h" @@ -61,7 +62,6 @@ struct kconsumerd_global_data { unsigned int need_update; } kconsumerd_data = { .fd_list.head = CDS_LIST_HEAD_INIT(kconsumerd_data.fd_list.head), - .need_update = 1, }; /* communication with splice */ @@ -70,12 +70,8 @@ static int kconsumerd_thread_pipe[2]; /* pipe to wake the poll thread when necessary */ static int kconsumerd_poll_pipe[2]; -/* - * TODO: create a should_quit pipe to let the signal handler wake up the - * fd receiver thread. It should be initialized before any signal can be - * received by the library. - */ - +/* to let the signal handler wake up the fd receiver thread */ +static int kconsumerd_should_quit[2]; /* timeout parameter, to control the polling thread grace period */ static int kconsumerd_poll_timeout = -1; @@ -129,7 +125,6 @@ static int kconsumerd_find_session_fd(int fd) cds_list_for_each_entry(iter, &kconsumerd_data.fd_list.head, list) { if (iter->sessiond_fd == fd) { DBG("Duplicate session fd %d", fd); - pthread_mutex_unlock(&kconsumerd_data.lock); return 1; } } @@ -182,6 +177,7 @@ static int kconsumerd_add_fd(struct lttcomm_kconsumerd_msg *buf, int consumerd_f tmp_fd->state = buf->state; tmp_fd->max_sb_size = buf->max_sb_size; strncpy(tmp_fd->path_name, buf->path_name, PATH_MAX); + tmp_fd->path_name[PATH_MAX - 1] = '\0'; /* Opening the tracefile in write mode */ ret = open(tmp_fd->path_name, @@ -554,6 +550,32 @@ end: return ret; } +/* + * kconsumerd_poll_socket + * + * Poll on the should_quit pipe and the command socket + * return -1 on error and should exit, 0 if data is + * available on the command socket + */ +int kconsumerd_poll_socket(struct pollfd *kconsumerd_sockpoll) +{ + int num_rdy; + + num_rdy = poll(kconsumerd_sockpoll, 2, -1); + if (num_rdy == -1) { + perror("Poll error"); + goto exit; + } + if (kconsumerd_sockpoll[0].revents == POLLIN) { + DBG("kconsumerd_should_quit wake up"); + goto exit; + } + return 0; + +exit: + return -1; +} + /* * kconsumerd_consumerd_recv_fd * @@ -561,10 +583,10 @@ end: * structures describing each fd (path name). * Returns the size of received data */ -static int kconsumerd_consumerd_recv_fd(int sfd, int size, +static int kconsumerd_consumerd_recv_fd(int sfd, + struct pollfd *kconsumerd_sockpoll, int size, enum kconsumerd_command cmd_type) { - struct msghdr msg; struct iovec iov[1]; int ret = 0, i, tmp2; struct cmsghdr *cmsg; @@ -575,8 +597,11 @@ static int kconsumerd_consumerd_recv_fd(int sfd, int size, /* the number of fds we are about to receive */ nb_fd = size / sizeof(struct lttcomm_kconsumerd_msg); + /* + * nb_fd is the number of fds we receive. One fd per recvmsg. + */ for (i = 0; i < nb_fd; i++) { - memset(&msg, 0, sizeof(msg)); + struct msghdr msg = { 0 }; /* Prepare to receive the structures */ iov[0].iov_base = &lkm; @@ -588,6 +613,10 @@ static int kconsumerd_consumerd_recv_fd(int sfd, int size, msg.msg_controllen = sizeof(recv_fd); DBG("Waiting to receive fd"); + if (kconsumerd_poll_socket(kconsumerd_sockpoll) < 0) { + goto end; + } + if ((ret = recvmsg(sfd, &msg, 0)) < 0) { perror("recvmsg"); continue; @@ -606,12 +635,13 @@ static int kconsumerd_consumerd_recv_fd(int sfd, int size, kconsumerd_send_error(KCONSUMERD_ERROR_RECV_FD); goto end; } + /* if we received fds */ if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { switch (cmd_type) { case ADD_STREAM: - DBG("kconsumerd_add_fd %s (%d)", lkm.path_name, (CMSG_DATA(cmsg)[0])); - ret = kconsumerd_add_fd(&lkm, (CMSG_DATA(cmsg)[0])); + DBG("kconsumerd_add_fd %s (%d)", lkm.path_name, ((int *) CMSG_DATA(cmsg))[0]); + ret = kconsumerd_add_fd(&lkm, ((int *) CMSG_DATA(cmsg))[0]); if (ret < 0) { kconsumerd_send_error(KCONSUMERD_OUTFD_ERROR); goto end; @@ -625,6 +655,9 @@ static int kconsumerd_consumerd_recv_fd(int sfd, int size, } /* signal the poll thread */ tmp2 = write(kconsumerd_poll_pipe[1], "4", 1); + if (tmp2 < 0) { + perror("write kconsumerd poll"); + } } else { ERR("Didn't received any fd"); kconsumerd_send_error(KCONSUMERD_ERROR_RECV_FD); @@ -736,6 +769,9 @@ void *kconsumerd_thread_poll_fds(void *data) if (pollfd[nb_fd].revents == POLLIN) { DBG("kconsumerd_poll_pipe wake up"); tmp2 = read(kconsumerd_poll_pipe[0], &tmp, 1); + if (tmp2 < 0) { + perror("read kconsumerd poll"); + } continue; } @@ -806,13 +842,34 @@ end: } /* - * kconsumerd_create_poll_pipe + * kconsumerd_init(void) * - * create the pipe to wake to polling thread when needed + * initialise the necessary environnement : + * - inform the polling thread to update the polling array + * - create the poll_pipe + * - create the should_quit pipe (for signal handler) */ -int kconsumerd_create_poll_pipe() +int kconsumerd_init(void) { - return pipe(kconsumerd_poll_pipe); + int ret; + + /* need to update the polling array at init time */ + kconsumerd_data.need_update = 1; + + ret = pipe(kconsumerd_poll_pipe); + if (ret < 0) { + perror("Error creating poll pipe"); + goto end; + } + + ret = pipe(kconsumerd_should_quit); + if (ret < 0) { + perror("Error creating recv pipe"); + goto end; + } + +end: + return ret; } /* @@ -825,6 +882,12 @@ void *kconsumerd_thread_receive_fds(void *data) { int sock, client_socket, ret; struct lttcomm_kconsumerd_header tmp; + /* + * structure to poll for incoming data on communication socket + * avoids making blocking sockets + */ + struct pollfd kconsumerd_sockpoll[2]; + DBG("Creating command socket %s", kconsumerd_command_sock_path); unlink(kconsumerd_command_sock_path); @@ -846,18 +909,46 @@ void *kconsumerd_thread_receive_fds(void *data) goto end; } - /* TODO: poll on socket and "should_quit" fd pipe */ - /* TODO: change blocking call into non-blocking call */ + ret = fcntl(client_socket, F_SETFL, O_NONBLOCK); + if (ret < 0) { + perror("fcntl O_NONBLOCK"); + goto end; + } + + /* prepare the FDs to poll : to client socket and the should_quit pipe */ + kconsumerd_sockpoll[0].fd = kconsumerd_should_quit[0]; + kconsumerd_sockpoll[0].events = POLLIN | POLLPRI; + kconsumerd_sockpoll[1].fd = client_socket; + kconsumerd_sockpoll[1].events = POLLIN | POLLPRI; + + if (kconsumerd_poll_socket(kconsumerd_sockpoll) < 0) { + goto end; + } + DBG("Connection on client_socket"); + /* Blocking call, waiting for transmission */ sock = lttcomm_accept_unix_sock(client_socket); if (sock <= 0) { WARN("On accept"); goto end; } + ret = fcntl(sock, F_SETFL, O_NONBLOCK); + if (ret < 0) { + perror("fcntl O_NONBLOCK"); + goto end; + } + + /* update the polling structure to poll on the established socket */ + kconsumerd_sockpoll[1].fd = sock; + kconsumerd_sockpoll[1].events = POLLIN | POLLPRI; + while (1) { + if (kconsumerd_poll_socket(kconsumerd_sockpoll) < 0) { + goto end; + } + DBG("Incoming fds on sock"); + /* We first get the number of fd we are about to receive */ - /* TODO: poll on sock and "should_quit" fd pipe */ - /* TODO: change recv into a non-blocking call */ ret = lttcomm_recv_unix_sock(sock, &tmp, sizeof(struct lttcomm_kconsumerd_header)); if (ret <= 0) { @@ -872,12 +963,15 @@ void *kconsumerd_thread_receive_fds(void *data) DBG("kconsumerd_thread_receive_fds received quit from signal"); goto end; } + /* we received a command to add or update fds */ - ret = kconsumerd_consumerd_recv_fd(sock, tmp.payload_size, tmp.cmd_type); + ret = kconsumerd_consumerd_recv_fd(sock, kconsumerd_sockpoll, + tmp.payload_size, tmp.cmd_type); if (ret <= 0) { ERR("Receiving the FD, exiting"); goto end; } + DBG("received fds on sock"); } end: @@ -911,7 +1005,7 @@ end: */ void kconsumerd_cleanup(void) { - struct kconsumerd_fd *iter; + struct kconsumerd_fd *iter, *tmp; /* remove the socket file */ unlink(kconsumerd_command_sock_path); @@ -921,21 +1015,24 @@ void kconsumerd_cleanup(void) * running (after joining on the threads), no need to protect * list iteration with mutex. */ - cds_list_for_each_entry(iter, &kconsumerd_data.fd_list.head, list) { + cds_list_for_each_entry_safe(iter, tmp, &kconsumerd_data.fd_list.head, list) { kconsumerd_del_fd(iter); } } /* + * kconsumerd_should_exit + * * Called from signal handler. */ void kconsumerd_should_exit(void) { + int ret; kconsumerd_quit = 1; - /* - * TODO: write into a should_quit pipe to wake up the fd - * receiver thread. - */ + ret = write(kconsumerd_should_quit[1], "4", 1); + if (ret < 0) { + perror("write kconsumerd quit"); + } } /*