/*
* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
+#include <sys/wait.h>
+#include <urcu/futex.h>
#include <unistd.h>
#include <ltt-kconsumerd.h>
#include "futex.h"
#include "kernel-ctl.h"
#include "ltt-sessiond.h"
+#include "shm.h"
#include "traceable-app.h"
#include "ust-ctl.h"
#include "utils.h"
static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */
static char kconsumerd_err_unix_sock_path[PATH_MAX]; /* kconsumerd error Unix socket path */
static char kconsumerd_cmd_unix_sock_path[PATH_MAX]; /* kconsumerd command Unix socket path */
+static char wait_shm_path[PATH_MAX]; /* global wait shm path for UST */
/* Sockets and FDs */
static int client_sock;
static pthread_mutex_t kconsumerd_pid_mutex; /* Mutex to control kconsumerd pid assignation */
-static int modprobe_remove_kernel_modules(void);
-
/*
* UST registration command queue. This queue is tied with a futex and uses a N
* wakers / 1 waiter implemented and detailed in futex.c/.h
*/
static struct ltt_session_list *session_list_ptr;
+/*
+ * Remove modules in reverse load order.
+ */
+static int modprobe_remove_kernel_modules(void)
+{
+ int ret = 0, i;
+ char modprobe[256];
+
+ for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
+ ret = snprintf(modprobe, sizeof(modprobe),
+ "/sbin/modprobe --remove --quiet %s",
+ kernel_modules_list[i].name);
+ if (ret < 0) {
+ perror("snprintf modprobe --remove");
+ goto error;
+ }
+ modprobe[sizeof(modprobe) - 1] = '\0';
+ ret = system(modprobe);
+ if (ret == -1) {
+ ERR("Unable to launch modprobe --remove for module %s",
+ kernel_modules_list[i].name);
+ } else if (kernel_modules_list[i].required
+ && WEXITSTATUS(ret) != 0) {
+ ERR("Unable to remove module %s",
+ kernel_modules_list[i].name);
+ } else {
+ DBG("Modprobe removal successful %s",
+ kernel_modules_list[i].name);
+ }
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Return group ID of the tracing group or -1 if not found.
+ */
static gid_t allowed_group(void)
{
struct group *grp;
return ret;
}
-#ifdef DISABLED
/*
- * Notify apps by writing 42 to a named pipe using name. Every applications
- * waiting for a ltt-sessiond will be notified and re-register automatically to
- * the session daemon.
- *
- * Return open or write error value.
+ * Notify UST applications using the shm mmap futex.
*/
-static int notify_apps(const char *name)
+static int notify_ust_apps(int active)
{
- int fd;
- int ret = -1;
+ char *wait_shm_mmap;
- DBG("Notify the global application pipe");
+ DBG("Notifying applications of session daemon state: %d", active);
- /* Try opening the global pipe */
- fd = open(name, O_WRONLY);
- if (fd < 0) {
+ /* See shm.c for this call implying mmap, shm and futex calls */
+ wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
+ if (wait_shm_mmap == NULL) {
goto error;
}
- /* Notify by writing on the pipe */
- ret = write(fd, "42", 2);
- if (ret < 0) {
- perror("write");
- }
+ /* Wake waiting process */
+ futex_wait_update((int32_t *) wait_shm_mmap, active);
+
+ /* Apps notified successfully */
+ return 0;
error:
- return ret;
+ return -1;
}
-#endif /* DISABLED */
/*
* Setup the outgoing data buffer for the response (llm) by allocating the
/* Adding the quit pipe */
kernel_pollfd[nb_fd - 1].fd = thread_quit_pipe[0];
+ kernel_pollfd[nb_fd - 1].events =
+ POLLHUP | POLLNVAL | POLLERR | POLLIN | POLLRDHUP | POLLPRI;
return nb_fd;
DBG("Channel found, updating kernel streams");
ret = kernel_open_channel_stream(channel);
if (ret < 0) {
- goto end;
+ goto error;
}
/*
ret = send_kconsumerd_channel_fds(session->kernel_session->consumer_fd,
channel);
if (ret < 0) {
- goto end;
+ goto error;
}
}
- goto end;
+ goto error;
}
}
unlock_session(session);
}
+ unlock_session_list();
+ return ret;
-end:
+error:
+ unlock_session(session);
unlock_session_list();
- if (session) {
- unlock_session(session);
- }
return ret;
}
goto error;
} else if (ret == 0) {
/* Should not happen since timeout is infinite */
+ ERR("Return value of poll is 0 with an infinite timeout.\n"
+ "This should not have happened! Continuing...");
continue;
}
/* First fd is always the quit pipe */
(*pollfd)[0].fd = thread_quit_pipe[0];
+ (*pollfd)[0].events =
+ POLLHUP | POLLNVAL | POLLERR | POLLIN | POLLRDHUP | POLLPRI;
+
/* Apps command pipe */
(*pollfd)[1].fd = apps_cmd_pipe[0];
(*pollfd)[1].events = POLLIN;
}
}
+ if (nb_fd < 2) {
+ /*
+ * There should *always* be at least two fds in the pollfd. This safety
+ * check make sure the poll() will actually try on those two pipes at
+ * best which are the thread_quit_pipe and apps_cmd_pipe.
+ */
+ nb_fd = 2;
+ MSG("nb_fd < 2 --> Not good! Continuing...");
+ }
+
/* Destroy old pollfd */
free(old_pollfd);
*/
static void *thread_manage_apps(void *data)
{
- int i, ret, count;
+ int i, ret, current_nb_fd;
unsigned int nb_fd = 2;
int update_poll_flag = 1;
struct pollfd *pollfd = NULL;
DBG("[thread] Manage application started");
ust_cmd.sock = -1;
+ current_nb_fd = nb_fd;
while (1) {
/* See if we have a valid socket to add to pollfd */
/* The pollfd struct must be updated */
if (update_poll_flag) {
- ret = update_apps_cmd_pollfd(nb_fd, ARRAY_SIZE(pollfd), &pollfd);
+ ret = update_apps_cmd_pollfd(nb_fd, current_nb_fd, &pollfd);
if (ret < 0) {
/* malloc failed so we quit */
goto error;
}
}
- count = nb_fd;
- for (i = 2; i < count; i++) {
+ current_nb_fd = nb_fd;
+ for (i = 2; i < current_nb_fd; i++) {
/* Apps socket is closed/hungup */
switch (pollfd[i].revents) {
case POLLERR:
}
}
- if (nb_fd != count) {
+ if (nb_fd != current_nb_fd) {
update_poll_flag = 1;
}
}
/* First fd is always the quit pipe */
pollfd[0].fd = thread_quit_pipe[0];
+ pollfd[0].events =
+ POLLHUP | POLLNVAL | POLLERR | POLLIN | POLLRDHUP | POLLPRI;
/* Apps socket */
pollfd[1].fd = apps_sock;
pollfd[1].events = POLLIN;
/* Notify all applications to register */
- //notify_apps(default_global_apps_pipe);
+ ret = notify_ust_apps(1);
+ if (ret < 0) {
+ ERR("Failed to notify applications or create the wait shared memory.\n"
+ "Execution continues but there might be problem for already running\n"
+ "applications that wishes to register.");
+ }
while (1) {
DBG("Accepting application registration");
/* Thread quit pipe has been closed. Killing thread. */
if (pollfd[0].revents == POLLNVAL) {
goto error;
- } else if (pollfd[1].revents == POLLERR) {
- ERR("Register apps socket poll error");
- goto error;
}
- sock = lttcomm_accept_unix_sock(apps_sock);
- if (sock < 0) {
+ switch (pollfd[1].revents) {
+ case POLLNVAL:
+ case POLLHUP:
+ case POLLRDHUP:
+ case POLLERR:
+ ERR("Register apps socket poll error");
goto error;
- }
+ case POLLIN:
+ sock = lttcomm_accept_unix_sock(apps_sock);
+ if (sock < 0) {
+ goto error;
+ }
- /* Create UST registration command for enqueuing */
- ust_cmd = malloc(sizeof(struct ust_command));
- if (ust_cmd == NULL) {
- perror("ust command malloc");
- goto error;
- }
+ /* Create UST registration command for enqueuing */
+ ust_cmd = malloc(sizeof(struct ust_command));
+ if (ust_cmd == NULL) {
+ perror("ust command malloc");
+ goto error;
+ }
- /*
- * Using message-based transmissions to ensure we don't have to deal
- * with partially received messages.
- */
- ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
- sizeof(struct ust_register_msg));
- if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
- if (ret < 0) {
- perror("lttcomm_recv_unix_sock register apps");
- } else {
- ERR("Wrong size received on apps register");
+ /*
+ * Using message-based transmissions to ensure we don't have to deal
+ * with partially received messages.
+ */
+ ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
+ sizeof(struct ust_register_msg));
+ if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
+ if (ret < 0) {
+ perror("lttcomm_recv_unix_sock register apps");
+ } else {
+ ERR("Wrong size received on apps register");
+ }
+ free(ust_cmd);
+ close(sock);
+ continue;
}
- free(ust_cmd);
- close(sock);
- continue;
- }
- ust_cmd->sock = sock;
+ ust_cmd->sock = sock;
- DBG("UST registration received with pid:%d ppid:%d uid:%d"
- " gid:%d sock:%d name:%s (version %d.%d)",
- ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
- ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
- ust_cmd->sock, ust_cmd->reg_msg.name,
- ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
- /*
- * Lock free enqueue the registration request.
- * The red pill has been taken! This apps will be part of the *system*
- */
- cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
+ DBG("UST registration received with pid:%d ppid:%d uid:%d"
+ " gid:%d sock:%d name:%s (version %d.%d)",
+ ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
+ ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
+ ust_cmd->sock, ust_cmd->reg_msg.name,
+ ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
+ /*
+ * Lock free enqueue the registration request.
+ * The red pill has been taken! This apps will be part of the *system*
+ */
+ cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
- /*
- * Wake the registration queue futex.
- * Implicit memory barrier with the exchange in cds_wfq_enqueue.
- */
- futex_nto1_wake(&ust_cmd_queue.futex);
+ /*
+ * Wake the registration queue futex.
+ * Implicit memory barrier with the exchange in cds_wfq_enqueue.
+ */
+ futex_nto1_wake(&ust_cmd_queue.futex);
+ break;
+ }
}
error:
- DBG("Register apps thread dying");
- if (apps_sock) {
- close(apps_sock);
- }
- if (sock) {
- close(sock);
- }
+ DBG("UST Registration thread dying");
+
+ /* Notify that the registration thread is gone */
+ notify_ust_apps(0);
+
+ close(apps_sock);
+ close(sock);
unlink(apps_unix_sock_path);
+
return NULL;
}
return ret;
}
-/*
- * modprobe_remove_kernel_modules
- * Remove modules in reverse load order.
- */
-static int modprobe_remove_kernel_modules(void)
-{
- int ret = 0, i;
- char modprobe[256];
-
- for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
- ret = snprintf(modprobe, sizeof(modprobe),
- "/sbin/modprobe --remove --quiet %s",
- kernel_modules_list[i].name);
- if (ret < 0) {
- perror("snprintf modprobe --remove");
- goto error;
- }
- modprobe[sizeof(modprobe) - 1] = '\0';
- ret = system(modprobe);
- if (ret == -1) {
- ERR("Unable to launch modprobe --remove for module %s",
- kernel_modules_list[i].name);
- } else if (kernel_modules_list[i].required
- && WEXITSTATUS(ret) != 0) {
- ERR("Unable to remove module %s",
- kernel_modules_list[i].name);
- } else {
- DBG("Modprobe removal successful %s",
- kernel_modules_list[i].name);
- }
- }
-
-error:
- return ret;
-}
-
/*
* mount_debugfs
*/
}
}
break;
+ case LTTNG_DOMAIN_UST_PID:
+ break;
default:
break;
}
kernel_wait_quiescent(kernel_tracer_fd);
break;
case LTTNG_DOMAIN_UST_PID:
+
break;
default:
ret = LTTCOMM_NOT_IMPLEMENTED;
/* First fd is always the quit pipe */
pollfd[0].fd = thread_quit_pipe[0];
+ pollfd[0].events =
+ POLLHUP | POLLNVAL | POLLERR | POLLIN | POLLRDHUP | POLLPRI;
/* Apps socket */
pollfd[1].fd = client_sock;
pollfd[1].events = POLLIN;
- /* Notify parent pid that we are ready
- * to accept command for client side.
+ /*
+ * Notify parent pid that we are ready to accept command for client side.
*/
if (opt_sig_parent) {
kill(ppid, SIGCHLD);
/* Thread quit pipe has been closed. Killing thread. */
if (pollfd[0].revents == POLLNVAL) {
goto error;
- } else if (pollfd[1].revents == POLLERR) {
- ERR("Client socket poll error");
- goto error;
}
- sock = lttcomm_accept_unix_sock(client_sock);
- if (sock < 0) {
+ switch (pollfd[1].revents) {
+ case POLLNVAL:
+ case POLLHUP:
+ case POLLERR:
+ ERR("Client socket poll error");
goto error;
- }
+ case POLLIN:
+ sock = lttcomm_accept_unix_sock(client_sock);
+ if (sock < 0) {
+ goto error;
+ }
- /* Allocate context command to process the client request */
- cmd_ctx = malloc(sizeof(struct command_ctx));
+ /* Allocate context command to process the client request */
+ cmd_ctx = malloc(sizeof(struct command_ctx));
- /* Allocate data buffer for reception */
- cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
- cmd_ctx->llm = NULL;
- cmd_ctx->session = NULL;
+ /* Allocate data buffer for reception */
+ cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
+ cmd_ctx->llm = NULL;
+ cmd_ctx->session = NULL;
- /*
- * Data is received from the lttng client. The struct
- * lttcomm_session_msg (lsm) contains the command and data request of
- * the client.
- */
- DBG("Receiving data from client ...");
- ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
- if (ret <= 0) {
- continue;
- }
+ /*
+ * Data is received from the lttng client. The struct
+ * lttcomm_session_msg (lsm) contains the command and data request of
+ * the client.
+ */
+ DBG("Receiving data from client ...");
+ ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
+ if (ret <= 0) {
+ continue;
+ }
- // TODO: Validate cmd_ctx including sanity check for security purpose.
+ // TODO: Validate cmd_ctx including sanity check for security purpose.
- /*
- * This function dispatch the work to the kernel or userspace tracer
- * libs and fill the lttcomm_lttng_msg data structure of all the needed
- * informations for the client. The command context struct contains
- * everything this function may needs.
- */
- ret = process_client_msg(cmd_ctx);
- if (ret < 0) {
- /* TODO: Inform client somehow of the fatal error. At this point,
- * ret < 0 means that a malloc failed (ENOMEM). */
- /* Error detected but still accept command */
- clean_command_ctx(&cmd_ctx);
- continue;
- }
+ /*
+ * This function dispatch the work to the kernel or userspace tracer
+ * libs and fill the lttcomm_lttng_msg data structure of all the needed
+ * informations for the client. The command context struct contains
+ * everything this function may needs.
+ */
+ ret = process_client_msg(cmd_ctx);
+ if (ret < 0) {
+ /* TODO: Inform client somehow of the fatal error. At this point,
+ * ret < 0 means that a malloc failed (ENOMEM). */
+ /* Error detected but still accept command */
+ clean_command_ctx(&cmd_ctx);
+ continue;
+ }
- DBG("Sending response (size: %d, retcode: %d)",
- cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
- ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
- if (ret < 0) {
- ERR("Failed to send data back to client");
- }
+ DBG("Sending response (size: %d, retcode: %d)",
+ cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
+ ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
+ if (ret < 0) {
+ ERR("Failed to send data back to client");
+ }
- clean_command_ctx(&cmd_ctx);
+ clean_command_ctx(&cmd_ctx);
- /* End of transmission */
- close(sock);
+ /* End of transmission */
+ close(sock);
+ break;
+ }
}
error:
snprintf(client_unix_sock_path, PATH_MAX,
DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
}
+
+ /* Set global SHM for ust */
+ if (strlen(wait_shm_path) == 0) {
+ snprintf(wait_shm_path, PATH_MAX,
+ DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
+ }
} else {
home_path = get_home_dir();
if (home_path == NULL) {
snprintf(client_unix_sock_path, PATH_MAX,
DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
}
+
+ /* Set global SHM for ust */
+ if (strlen(wait_shm_path) == 0) {
+ snprintf(wait_shm_path, PATH_MAX,
+ DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
+ }
}
DBG("Client socket path %s", client_unix_sock_path);