From: David Goulet Date: Thu, 3 Nov 2011 15:39:31 +0000 (-0400) Subject: Merge master branch X-Git-Url: http://git.lttng.org./?a=commitdiff_plain;h=b3342c3941acee14b4ca1e13e593411ca035165c;p=lttng-tools.git Merge master branch Signed-off-by: David Goulet --- b3342c3941acee14b4ca1e13e593411ca035165c diff --cc Makefile.am index 8815acebe,44f17148b..279a73ae5 --- a/Makefile.am +++ b/Makefile.am @@@ -1,15 -1,14 +1,15 @@@ ACLOCAL_AMFLAGS = -I config -SUBDIRS = liblttng-sessiond-comm \ +SUBDIRS = benchmark \ + liblttng-sessiond-comm \ libkernelctl \ - liblttngkconsumerd \ + liblttng-kconsumer \ + liblttng-ustconsumer \ + liblttng-consumer \ + lttng-consumerd \ liblttngctl \ - libustcomm \ - libustctl \ lttng \ - ltt-kconsumerd \ - ltt-sessiond \ + lttng-sessiond \ tests \ include \ doc diff --cc configure.ac index ed625263b,3ead48e7b..59c6a2838 --- a/configure.ac +++ b/configure.ac @@@ -74,15 -88,14 +93,15 @@@ AC_SUBST(DEFAULT_INCLUDES AC_CONFIG_FILES([ Makefile include/Makefile + benchmark/Makefile libkernelctl/Makefile - liblttngkconsumerd/Makefile + liblttng-consumer/Makefile + liblttng-kconsumer/Makefile + liblttng-ustconsumer/Makefile liblttngctl/Makefile liblttng-sessiond-comm/Makefile - libustctl/Makefile - libustcomm/Makefile - ltt-kconsumerd/Makefile - ltt-sessiond/Makefile + lttng-consumerd/Makefile + lttng-sessiond/Makefile lttng/Makefile tests/Makefile doc/Makefile diff --cc lttng-sessiond/Makefile.am index 000000000,78179bd7a..9496008b2 mode 000000,100644..100644 --- a/lttng-sessiond/Makefile.am +++ b/lttng-sessiond/Makefile.am @@@ -1,0 -1,45 +1,47 @@@ -AM_CPPFLAGS = -I$(top_srcdir)/include \ - -DINSTALL_BIN_PATH=\""$(bindir)"\" ++AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/benchmark \ ++ -DINSTALL_BIN_PATH=\"$(bindir)\" + + AM_CFLAGS = -fno-strict-aliasing + + bin_PROGRAMS = lttng-sessiond + + if COMPAT_EPOLL + COMPAT=compat/compat-epoll.c + else + COMPAT=compat/compat-poll.c + endif + + lttng_sessiond_SOURCES = utils.c utils.h \ + hashtable.c hashtable.h \ + compat/poll.h $(COMPAT) \ + trace-kernel.c trace-kernel.h \ + kernel-ctl.c kernel-ctl.h \ + ust-ctl.h ust-app.h trace-ust.h \ + context.c context.h \ + channel.c channel.h \ + event.c event.h \ + futex.c futex.h \ + shm.c shm.h \ + session.c session.h \ + ../hashtable/rculfhash.c \ + ../hashtable/rculfhash.h \ + ../hashtable/hash.c ../hashtable/hash.h + + if LTTNG_TOOLS_HAVE_UST + lttng_sessiond_SOURCES += trace-ust.c ust-app.c ust-consumer.c ust-consumer.h + endif + + # Add main.c at the end for compile order + lttng_sessiond_SOURCES += lttng-sessiond.h main.c + + # link on liblttngctl for check if sessiond is already alive. + lttng_sessiond_LDADD = -lrt -lurcu-cds -lurcu \ + $(top_builddir)/liblttng-sessiond-comm/liblttng-sessiond-comm.la \ + $(top_builddir)/libkernelctl/libkernelctl.la \ - $(top_builddir)/liblttngctl/liblttngctl.la ++ $(top_builddir)/libustctl/libustctl.la \ ++ $(top_builddir)/liblttngctl/liblttngctl.la \ ++ $(top_builddir)/benchmark/liblttng-benchmark.la + + if LTTNG_TOOLS_HAVE_UST + lttng_sessiond_LDADD += -llttng-ust-comm -lustctl + endif diff --cc lttng-sessiond/main.c index 000000000,ea3853c1a..04e5efb4f mode 000000,100644..100644 --- a/lttng-sessiond/main.c +++ b/lttng-sessiond/main.c @@@ -1,0 -1,3913 +1,3984 @@@ + /* + * Copyright (C) 2011 - David Goulet + * Mathieu Desnoyers + * + * 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; only version 2 of the License. + * + * 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. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 59 Temple + * Place - Suite 330, Boston, MA 02111-1307, USA. + */ + + #define _GNU_SOURCE + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + #include + + #include + #include + #include + + #include + + #include "channel.h" + #include "compat/poll.h" + #include "context.h" + #include "event.h" + #include "futex.h" + #include "hashtable.h" + #include "kernel-ctl.h" + #include "lttng-sessiond.h" + #include "shm.h" + #include "ust-app.h" + #include "ust-ctl.h" + #include "utils.h" + + struct consumer_data { + enum lttng_consumer_type type; + + pthread_t thread; /* Worker thread interacting with the consumer */ + sem_t sem; + + /* Mutex to control consumerd pid assignation */ + pthread_mutex_t pid_mutex; + pid_t pid; + + int err_sock; + int cmd_sock; + + /* consumer error and command Unix socket path */ + char err_unix_sock_path[PATH_MAX]; + char cmd_unix_sock_path[PATH_MAX]; + }; + ++#include "benchmark.h" ++ + /* Const values */ + const char default_home_dir[] = DEFAULT_HOME_DIR; + const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP; + const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR; + const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE; + + /* Variables */ + int opt_verbose; /* Not static for lttngerr.h */ + int opt_verbose_consumer; /* Not static for lttngerr.h */ + int opt_quiet; /* Not static for lttngerr.h */ + + const char *progname; + const char *opt_tracing_group; + static int opt_sig_parent; + static int opt_daemon; + static int is_root; /* Set to 1 if the daemon is running as root */ + static pid_t ppid; /* Parent PID for --sig-parent option */ + + /* Consumer daemon specific control data */ + static struct consumer_data kconsumer_data = { + .type = LTTNG_CONSUMER_KERNEL, + }; + static struct consumer_data ustconsumer_data = { + .type = LTTNG_CONSUMER_UST, + }; + + static int dispatch_thread_exit; + + /* Global application Unix socket path */ + static char apps_unix_sock_path[PATH_MAX]; + /* Global client Unix socket path */ + static char client_unix_sock_path[PATH_MAX]; + /* global wait shm path for UST */ + static char wait_shm_path[PATH_MAX]; + + /* Sockets and FDs */ + static int client_sock; + static int apps_sock; + static int kernel_tracer_fd; + static int kernel_poll_pipe[2]; + + /* + * Quit pipe for all threads. This permits a single cancellation point + * for all threads when receiving an event on the pipe. + */ + static int thread_quit_pipe[2]; + + /* + * This pipe is used to inform the thread managing application communication + * that a command is queued and ready to be processed. + */ + static int apps_cmd_pipe[2]; + + /* Pthread, Mutexes and Semaphores */ + static pthread_t apps_thread; + static pthread_t reg_apps_thread; + static pthread_t client_thread; + static pthread_t kernel_thread; + static pthread_t dispatch_thread; + + + /* + * 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 + * + * The thread_manage_apps and thread_dispatch_ust_registration interact with + * this queue and the wait/wake scheme. + */ + static struct ust_cmd_queue ust_cmd_queue; + + /* + * Pointer initialized before thread creation. + * + * This points to the tracing session list containing the session count and a + * mutex lock. The lock MUST be taken if you iterate over the list. The lock + * MUST NOT be taken if you call a public function in session.c. + * + * The lock is nested inside the structure: session_list_ptr->lock. Please use + * session_lock_list and session_unlock_list for lock acquisition. + */ + static struct ltt_session_list *session_list_ptr; + + /* + * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set. + */ + static int create_thread_poll_set(struct lttng_poll_event *events, + unsigned int size) + { + int ret; + + if (events == NULL || size == 0) { + ret = -1; + goto error; + } + + ret = lttng_poll_create(events, size, LTTNG_CLOEXEC); + if (ret < 0) { + goto error; + } + + /* Add quit pipe */ + ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN); + if (ret < 0) { + goto error; + } + + return 0; + + error: + return ret; + } + + /* + * Check if the thread quit pipe was triggered. + * + * Return 1 if it was triggered else 0; + */ + static int check_thread_quit_pipe(int fd, uint32_t events) + { + if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) { + return 1; + } + + return 0; + } + + /* + * 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 -r -q %s", + kernel_modules_list[i].name); + if (ret < 0) { + perror("snprintf modprobe -r"); + goto error; + } + modprobe[sizeof(modprobe) - 1] = '\0'; + ret = system(modprobe); + if (ret == -1) { + ERR("Unable to launch modprobe -r 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; + + if (opt_tracing_group) { + grp = getgrnam(opt_tracing_group); + } else { + grp = getgrnam(default_tracing_group); + } + if (!grp) { + return -1; + } else { + return grp->gr_gid; + } + } + + /* + * Init thread quit pipe. + * + * Return -1 on error or 0 if all pipes are created. + */ + static int init_thread_quit_pipe(void) + { + int ret; + + ret = pipe2(thread_quit_pipe, O_CLOEXEC); + if (ret < 0) { + perror("thread quit pipe"); + goto error; + } + + error: + return ret; + } + + /* + * Complete teardown of a kernel session. This free all data structure related + * to a kernel session and update counter. + */ + static void teardown_kernel_session(struct ltt_session *session) + { + if (session->kernel_session != NULL) { + DBG("Tearing down kernel session"); + + /* + * If a custom kernel consumer was registered, close the socket before + * tearing down the complete kernel session structure + */ + if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) { + lttcomm_close_unix_sock(session->kernel_session->consumer_fd); + } + + trace_kernel_destroy_session(session->kernel_session); + /* Extra precaution */ + session->kernel_session = NULL; + } + } + + /* + * Complete teardown of all UST sessions. This will free everything on his path + * and destroy the core essence of all ust sessions :) + */ + static void teardown_ust_session(struct ltt_session *session) + { + DBG("Tearing down UST session(s)"); + + trace_ust_destroy_session(session->ust_session); + } + + /* + * Stop all threads by closing the thread quit pipe. + */ + static void stop_threads(void) + { + int ret; + + /* Stopping all threads */ + DBG("Terminating all threads"); + ret = notify_thread_pipe(thread_quit_pipe[1]); + if (ret < 0) { + ERR("write error on thread quit pipe"); + } + + /* Dispatch thread */ + dispatch_thread_exit = 1; + futex_nto1_wake(&ust_cmd_queue.futex); + } + + /* + * Cleanup the daemon + */ + static void cleanup(void) + { + int ret; + char *cmd; + struct ltt_session *sess, *stmp; + + DBG("Cleaning up"); + + /* */ + MSG("%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm" + "Matthew, BEET driven development works!%c[%dm", + 27, 1, 31, 27, 0, 27, 1, 33, 27, 0); + /* */ + + if (is_root) { + DBG("Removing %s directory", LTTNG_RUNDIR); + ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR); + if (ret < 0) { + ERR("asprintf failed. Something is really wrong!"); + } + + /* Remove lttng run directory */ + ret = system(cmd); + if (ret < 0) { + ERR("Unable to clean " LTTNG_RUNDIR); + } + } + + DBG("Cleaning up all session"); + + /* Destroy session list mutex */ + if (session_list_ptr != NULL) { + pthread_mutex_destroy(&session_list_ptr->lock); + + /* Cleanup ALL session */ + cds_list_for_each_entry_safe(sess, stmp, + &session_list_ptr->head, list) { + teardown_kernel_session(sess); + teardown_ust_session(sess); + free(sess); + } + } + + DBG("Closing all UST sockets"); + ust_app_clean_list(); + + pthread_mutex_destroy(&kconsumer_data.pid_mutex); + + DBG("Closing kernel fd"); + close(kernel_tracer_fd); + + if (is_root) { + DBG("Unloading kernel modules"); + modprobe_remove_kernel_modules(); + } + + close(thread_quit_pipe[0]); + close(thread_quit_pipe[1]); ++ ++ /* OUTPUT BENCHMARK RESULTS */ ++ bench_init(); ++ ++ if (getenv("BENCH_UST_NOTIFY")) { ++ bench_print_ust_notification(); ++ } ++ ++ if (getenv("BENCH_UST_REGISTER")) { ++ bench_print_ust_register(); ++ bench_print_ust_unregister(); ++ } ++ ++ if (getenv("BENCH_BOOT_PROCESS")) { ++ bench_print_boot_process(); ++ } ++ ++ bench_close(); ++ /* END BENCHMARK */ + } + + /* + * Send data on a unix socket using the liblttsessiondcomm API. + * + * Return lttcomm error code. + */ + static int send_unix_sock(int sock, void *buf, size_t len) + { + /* Check valid length */ + if (len <= 0) { + return -1; + } + + return lttcomm_send_unix_sock(sock, buf, len); + } + + /* + * Free memory of a command context structure. + */ + static void clean_command_ctx(struct command_ctx **cmd_ctx) + { + DBG("Clean command context structure"); + if (*cmd_ctx) { + if ((*cmd_ctx)->llm) { + free((*cmd_ctx)->llm); + } + if ((*cmd_ctx)->lsm) { + free((*cmd_ctx)->lsm); + } + free(*cmd_ctx); + *cmd_ctx = NULL; + } + } + + /* + * Send all stream fds of kernel channel to the consumer. + */ + static int send_kconsumer_channel_streams(struct consumer_data *consumer_data, + int sock, struct ltt_kernel_channel *channel) + { + int ret; + struct ltt_kernel_stream *stream; + struct lttcomm_consumer_msg lkm; + + DBG("Sending streams of channel %s to kernel consumer", + channel->channel->name); + + /* Send channel */ + lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL; + lkm.u.channel.channel_key = channel->fd; + lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size; + lkm.u.channel.mmap_len = 0; /* for kernel */ + DBG("Sending channel %d to consumer", lkm.u.channel.channel_key); + ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm)); + if (ret < 0) { + perror("send consumer channel"); + goto error; + } + + /* Send streams */ + cds_list_for_each_entry(stream, &channel->stream_list.head, list) { + if (!stream->fd) { + continue; + } + lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM; + lkm.u.stream.channel_key = channel->fd; + lkm.u.stream.stream_key = stream->fd; + lkm.u.stream.state = stream->state; + lkm.u.stream.output = channel->channel->attr.output; + lkm.u.stream.mmap_len = 0; /* for kernel */ + strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1); + lkm.u.stream.path_name[PATH_MAX - 1] = '\0'; + DBG("Sending stream %d to consumer", lkm.u.stream.stream_key); + ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm)); + if (ret < 0) { + perror("send consumer stream"); + goto error; + } + ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1); + if (ret < 0) { + perror("send consumer stream ancillary data"); + goto error; + } + } + + DBG("consumer channel streams sent"); + + return 0; + + error: + return ret; + } + + /* + * Send all stream fds of the kernel session to the consumer. + */ + static int send_kconsumer_session_streams(struct consumer_data *consumer_data, + struct ltt_kernel_session *session) + { + int ret; + struct ltt_kernel_channel *chan; + struct lttcomm_consumer_msg lkm; + int sock = session->consumer_fd; + + DBG("Sending metadata stream fd"); + + /* Extra protection. It's NOT supposed to be set to 0 at this point */ + if (session->consumer_fd == 0) { + session->consumer_fd = consumer_data->cmd_sock; + } + + if (session->metadata_stream_fd != 0) { + /* Send metadata channel fd */ + lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL; + lkm.u.channel.channel_key = session->metadata->fd; + lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size; + lkm.u.channel.mmap_len = 0; /* for kernel */ + DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key); + ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm)); + if (ret < 0) { + perror("send consumer channel"); + goto error; + } + + /* Send metadata stream fd */ + lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM; + lkm.u.stream.channel_key = session->metadata->fd; + lkm.u.stream.stream_key = session->metadata_stream_fd; + lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM; + lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT; + lkm.u.stream.mmap_len = 0; /* for kernel */ + strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1); + lkm.u.stream.path_name[PATH_MAX - 1] = '\0'; + DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key); + ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm)); + if (ret < 0) { + perror("send consumer stream"); + goto error; + } + ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1); + if (ret < 0) { + perror("send consumer stream"); + goto error; + } + } + + cds_list_for_each_entry(chan, &session->channel_list.head, list) { + ret = send_kconsumer_channel_streams(consumer_data, sock, chan); + if (ret < 0) { + goto error; + } + } + + DBG("consumer fds (metadata and channel streams) sent"); + + return 0; + + error: + return ret; + } + + /* + * Notify UST applications using the shm mmap futex. + */ + static int notify_ust_apps(int active) + { + char *wait_shm_mmap; + + DBG("Notifying applications of session daemon state: %d", active); + ++ tracepoint(ust_notify_apps_start); ++ + /* 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; + } + + /* Wake waiting process */ + futex_wait_update((int32_t *) wait_shm_mmap, active); + ++ tracepoint(ust_notify_apps_stop); ++ + /* Apps notified successfully */ + return 0; + + error: + return -1; + } + + /* + * Setup the outgoing data buffer for the response (llm) by allocating the + * right amount of memory and copying the original information from the lsm + * structure. + * + * Return total size of the buffer pointed by buf. + */ + static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size) + { + int ret, buf_size; + + buf_size = size; + + cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size); + if (cmd_ctx->llm == NULL) { + perror("malloc"); + ret = -ENOMEM; + goto error; + } + + /* Copy common data */ + cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type; + cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid; + + cmd_ctx->llm->data_size = size; + cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size; + + return buf_size; + + error: + return ret; + } + + /* + * Update the kernel poll set of all channel fd available over all tracing + * session. Add the wakeup pipe at the end of the set. + */ + static int update_kernel_poll(struct lttng_poll_event *events) + { + int ret; + struct ltt_session *session; + struct ltt_kernel_channel *channel; + + DBG("Updating kernel poll set"); + + session_lock_list(); + cds_list_for_each_entry(session, &session_list_ptr->head, list) { + session_lock(session); + if (session->kernel_session == NULL) { + session_unlock(session); + continue; + } + + cds_list_for_each_entry(channel, + &session->kernel_session->channel_list.head, list) { + /* Add channel fd to the kernel poll set */ + ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM); + if (ret < 0) { + session_unlock(session); + goto error; + } + DBG("Channel fd %d added to kernel set", channel->fd); + } + session_unlock(session); + } + session_unlock_list(); + + return 0; + + error: + session_unlock_list(); + return -1; + } + + /* + * Find the channel fd from 'fd' over all tracing session. When found, check + * for new channel stream and send those stream fds to the kernel consumer. + * + * Useful for CPU hotplug feature. + */ + static int update_kernel_stream(struct consumer_data *consumer_data, int fd) + { + int ret = 0; + struct ltt_session *session; + struct ltt_kernel_channel *channel; + + DBG("Updating kernel streams for channel fd %d", fd); + + session_lock_list(); + cds_list_for_each_entry(session, &session_list_ptr->head, list) { + session_lock(session); + if (session->kernel_session == NULL) { + session_unlock(session); + continue; + } + + /* This is not suppose to be 0 but this is an extra security check */ + if (session->kernel_session->consumer_fd == 0) { + session->kernel_session->consumer_fd = consumer_data->cmd_sock; + } + + cds_list_for_each_entry(channel, + &session->kernel_session->channel_list.head, list) { + if (channel->fd == fd) { + DBG("Channel found, updating kernel streams"); + ret = kernel_open_channel_stream(channel); + if (ret < 0) { + goto error; + } + + /* + * Have we already sent fds to the consumer? If yes, it means + * that tracing is started so it is safe to send our updated + * stream fds. + */ + if (session->kernel_session->consumer_fds_sent == 1) { + ret = send_kconsumer_channel_streams(consumer_data, + session->kernel_session->consumer_fd, channel); + if (ret < 0) { + goto error; + } + } + goto error; + } + } + session_unlock(session); + } + session_unlock_list(); + return ret; + + error: + session_unlock(session); + session_unlock_list(); + return ret; + } + + /* + * This thread manage event coming from the kernel. + * + * Features supported in this thread: + * -) CPU Hotplug + */ + static void *thread_manage_kernel(void *data) + { + int ret, i, pollfd, update_poll_flag = 1; + uint32_t revents, nb_fd; + char tmp; + struct lttng_poll_event events; + ++ tracepoint(sessiond_th_kern_start); ++ + DBG("Thread manage kernel started"); + + ret = create_thread_poll_set(&events, 2); + if (ret < 0) { + goto error; + } + + ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN); + if (ret < 0) { + goto error; + } + + while (1) { + if (update_poll_flag == 1) { + /* + * Reset number of fd in the poll set. Always 2 since there is the thread + * quit pipe and the kernel pipe. + */ + events.nb_fd = 2; + + ret = update_kernel_poll(&events); + if (ret < 0) { + goto error; + } + update_poll_flag = 0; + } + + nb_fd = LTTNG_POLL_GETNB(&events); + + DBG("Thread kernel polling on %d fds", nb_fd); + + /* Zeroed the poll events */ + lttng_poll_reset(&events); + ++ tracepoint(sessiond_th_kern_poll); ++ + /* Poll infinite value of time */ + ret = lttng_poll_wait(&events, -1); + if (ret < 0) { + 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; + } + + for (i = 0; i < nb_fd; i++) { + /* Fetch once the poll data */ + revents = LTTNG_POLL_GETEV(&events, i); + pollfd = LTTNG_POLL_GETFD(&events, i); + + /* Thread quit pipe has been closed. Killing thread. */ + ret = check_thread_quit_pipe(pollfd, revents); + if (ret) { + goto error; + } + + /* Check for data on kernel pipe */ + if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) { + ret = read(kernel_poll_pipe[0], &tmp, 1); + update_poll_flag = 1; + continue; + } else { + /* + * New CPU detected by the kernel. Adding kernel stream to + * kernel session and updating the kernel consumer + */ + if (revents & LPOLLIN) { + ret = update_kernel_stream(&kconsumer_data, pollfd); + if (ret < 0) { + continue; + } + break; + /* + * TODO: We might want to handle the LPOLLERR | LPOLLHUP + * and unregister kernel stream at this point. + */ + } + } + } + } + + error: + DBG("Kernel thread dying"); + close(kernel_poll_pipe[0]); + close(kernel_poll_pipe[1]); + + lttng_poll_clean(&events); + + return NULL; + } + + /* + * This thread manage the consumer error sent back to the session daemon. + */ + static void *thread_manage_consumer(void *data) + { + int sock = 0, i, ret, pollfd; + uint32_t revents, nb_fd; + enum lttcomm_return_code code; + struct lttng_poll_event events; + struct consumer_data *consumer_data = data; + ++ tracepoint(sessiond_th_kcon_start); ++ + DBG("[thread] Manage consumer started"); + + ret = lttcomm_listen_unix_sock(consumer_data->err_sock); + if (ret < 0) { + goto error; + } + + /* + * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock. + * Nothing more will be added to this poll set. + */ + ret = create_thread_poll_set(&events, 2); + if (ret < 0) { + goto error; + } + + ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP); + if (ret < 0) { + goto error; + } + + nb_fd = LTTNG_POLL_GETNB(&events); + ++ tracepoint(sessiond_th_kcon_poll); ++ + /* Inifinite blocking call, waiting for transmission */ + ret = lttng_poll_wait(&events, -1); + if (ret < 0) { + goto error; + } + + for (i = 0; i < nb_fd; i++) { + /* Fetch once the poll data */ + revents = LTTNG_POLL_GETEV(&events, i); + pollfd = LTTNG_POLL_GETFD(&events, i); + + /* Thread quit pipe has been closed. Killing thread. */ + ret = check_thread_quit_pipe(pollfd, revents); + if (ret) { + goto error; + } + + /* Event on the registration socket */ + if (pollfd == consumer_data->err_sock) { + if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { + ERR("consumer err socket poll error"); + goto error; + } + } + } + + sock = lttcomm_accept_unix_sock(consumer_data->err_sock); + if (sock < 0) { + goto error; + } + + DBG2("Receiving code from consumer err_sock"); + + /* Getting status code from kconsumerd */ + ret = lttcomm_recv_unix_sock(sock, &code, + sizeof(enum lttcomm_return_code)); + if (ret <= 0) { + goto error; + } + + if (code == CONSUMERD_COMMAND_SOCK_READY) { + consumer_data->cmd_sock = + lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path); + if (consumer_data->cmd_sock < 0) { + sem_post(&consumer_data->sem); + PERROR("consumer connect"); + goto error; + } + /* Signal condition to tell that the kconsumerd is ready */ + sem_post(&consumer_data->sem); + DBG("consumer command socket ready"); + } else { + ERR("consumer error when waiting for SOCK_READY : %s", + lttcomm_get_readable_code(-code)); + goto error; + } + + /* Remove the kconsumerd error sock since we've established a connexion */ + ret = lttng_poll_del(&events, consumer_data->err_sock); + if (ret < 0) { + goto error; + } + + ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP); + if (ret < 0) { + goto error; + } + + /* Update number of fd */ + nb_fd = LTTNG_POLL_GETNB(&events); + + /* Inifinite blocking call, waiting for transmission */ + ret = lttng_poll_wait(&events, -1); + if (ret < 0) { + goto error; + } + + for (i = 0; i < nb_fd; i++) { + /* Fetch once the poll data */ + revents = LTTNG_POLL_GETEV(&events, i); + pollfd = LTTNG_POLL_GETFD(&events, i); + + /* Thread quit pipe has been closed. Killing thread. */ + ret = check_thread_quit_pipe(pollfd, revents); + if (ret) { + goto error; + } + + /* Event on the kconsumerd socket */ + if (pollfd == sock) { + if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { + ERR("consumer err socket second poll error"); + goto error; + } + } + } + + /* Wait for any kconsumerd error */ + ret = lttcomm_recv_unix_sock(sock, &code, + sizeof(enum lttcomm_return_code)); + if (ret <= 0) { + ERR("consumer closed the command socket"); + goto error; + } + + ERR("consumer return code : %s", lttcomm_get_readable_code(-code)); + + error: + DBG("consumer thread dying"); + close(consumer_data->err_sock); + close(consumer_data->cmd_sock); + close(sock); + + unlink(consumer_data->err_unix_sock_path); + unlink(consumer_data->cmd_unix_sock_path); + consumer_data->pid = 0; + + lttng_poll_clean(&events); + + return NULL; + } + + /* + * This thread manage application communication. + */ + static void *thread_manage_apps(void *data) + { + int i, ret, pollfd; + uint32_t revents, nb_fd; + struct ust_command ust_cmd; + struct lttng_poll_event events; + ++ tracepoint(sessiond_th_apps_start); ++ + DBG("[thread] Manage application started"); + + rcu_register_thread(); + rcu_thread_online(); + + ret = create_thread_poll_set(&events, 2); + if (ret < 0) { + goto error; + } + + ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP); + if (ret < 0) { + goto error; + } + + while (1) { + /* Zeroed the events structure */ + lttng_poll_reset(&events); + + nb_fd = LTTNG_POLL_GETNB(&events); + + DBG("Apps thread polling on %d fds", nb_fd); + ++ tracepoint(sessiond_th_apps_poll); ++ + /* Inifinite blocking call, waiting for transmission */ + ret = lttng_poll_wait(&events, -1); + if (ret < 0) { + goto error; + } + + for (i = 0; i < nb_fd; i++) { + /* Fetch once the poll data */ + revents = LTTNG_POLL_GETEV(&events, i); + pollfd = LTTNG_POLL_GETFD(&events, i); + + /* Thread quit pipe has been closed. Killing thread. */ + ret = check_thread_quit_pipe(pollfd, revents); + if (ret) { + goto error; + } + + /* Inspect the apps cmd pipe */ + if (pollfd == apps_cmd_pipe[0]) { + if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { + ERR("Apps command pipe error"); + goto error; + } else if (revents & LPOLLIN) { ++ tracepoint(ust_register_read_start); + /* Empty pipe */ + ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd)); + if (ret < 0 || ret < sizeof(ust_cmd)) { + perror("read apps cmd pipe"); + goto error; + } ++ tracepoint(ust_register_read_stop); + ++ tracepoint(ust_register_add_start); + /* Register applicaton to the session daemon */ + ret = ust_app_register(&ust_cmd.reg_msg, + ust_cmd.sock); + if (ret < 0) { + /* Only critical ENOMEM error can be returned here */ + goto error; + } ++ tracepoint(ust_register_add_stop); + ++ tracepoint(ust_register_done_start); + ret = ustctl_register_done(ust_cmd.sock); + if (ret < 0) { + /* + * If the registration is not possible, we simply + * unregister the apps and continue + */ + ust_app_unregister(ust_cmd.sock); + } else { + /* + * We just need here to monitor the close of the UST + * socket and poll set monitor those by default. + */ + ret = lttng_poll_add(&events, ust_cmd.sock, 0); + if (ret < 0) { + goto error; + } + + DBG("Apps with sock %d added to poll set", + ust_cmd.sock); + } ++ tracepoint(ust_register_done_stop); + break; + } + } else { + /* + * At this point, we know that a registered application made + * the event at poll_wait. + */ + if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { + /* Removing from the poll set */ + ret = lttng_poll_del(&events, pollfd); + if (ret < 0) { + goto error; + } + + /* Socket closed */ + ust_app_unregister(pollfd); + break; + } + } + } + } + + error: + DBG("Application communication apps dying"); + close(apps_cmd_pipe[0]); + close(apps_cmd_pipe[1]); + + lttng_poll_clean(&events); + + rcu_thread_offline(); + rcu_unregister_thread(); + return NULL; + } + + /* + * Dispatch request from the registration threads to the application + * communication thread. + */ + static void *thread_dispatch_ust_registration(void *data) + { + int ret; + struct cds_wfq_node *node; + struct ust_command *ust_cmd = NULL; + ++ tracepoint(sessiond_th_dispatch_start); ++ + DBG("[thread] Dispatch UST command started"); + + while (!dispatch_thread_exit) { + /* Atomically prepare the queue futex */ + futex_nto1_prepare(&ust_cmd_queue.futex); + + do { ++ tracepoint(sessiond_th_dispatch_block); ++ + /* Dequeue command for registration */ + node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue); + if (node == NULL) { + DBG("Woken up but nothing in the UST command queue"); + /* Continue thread execution */ + break; + } + ++ tracepoint(ust_dispatch_register_start); ++ + ust_cmd = caa_container_of(node, struct ust_command, node); + + DBG("Dispatching UST registration 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); + /* + * Inform apps thread of the new application registration. This + * call is blocking so we can be assured that the data will be read + * at some point in time or wait to the end of the world :) + */ + ret = write(apps_cmd_pipe[1], ust_cmd, + sizeof(struct ust_command)); + if (ret < 0) { + perror("write apps cmd pipe"); + if (errno == EBADF) { + /* + * We can't inform the application thread to process + * registration. We will exit or else application + * registration will not occur and tracing will never + * start. + */ + goto error; + } + } + free(ust_cmd); + } while (node != NULL); + ++ tracepoint(ust_dispatch_register_stop); ++ + /* Futex wait on queue. Blocking call on futex() */ + futex_nto1_wait(&ust_cmd_queue.futex); + } + + error: + DBG("Dispatch thread dying"); + return NULL; + } + + /* + * This thread manage application registration. + */ + static void *thread_registration_apps(void *data) + { + int sock = 0, i, ret, pollfd; + uint32_t revents, nb_fd; + struct lttng_poll_event events; + /* + * Get allocated in this thread, enqueued to a global queue, dequeued and + * freed in the manage apps thread. + */ + struct ust_command *ust_cmd = NULL; + ++ tracepoint(sessiond_th_reg_start); ++ + DBG("[thread] Manage application registration started"); + + ret = lttcomm_listen_unix_sock(apps_sock); + if (ret < 0) { + goto error; + } + + /* + * Pass 2 as size here for the thread quit pipe and apps socket. Nothing + * more will be added to this poll set. + */ + ret = create_thread_poll_set(&events, 2); + if (ret < 0) { + goto error; + } + + /* Add the application registration socket */ + ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP); + if (ret < 0) { + goto error; + } + + /* Notify all applications to register */ + 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\n" + "running applications that wishes to register."); + } + + while (1) { + DBG("Accepting application registration"); + ++ tracepoint(sessiond_th_reg_poll); ++ + nb_fd = LTTNG_POLL_GETNB(&events); + + /* Inifinite blocking call, waiting for transmission */ + ret = lttng_poll_wait(&events, -1); + if (ret < 0) { + goto error; + } + + for (i = 0; i < nb_fd; i++) { + /* Fetch once the poll data */ + revents = LTTNG_POLL_GETEV(&events, i); + pollfd = LTTNG_POLL_GETFD(&events, i); + + /* Thread quit pipe has been closed. Killing thread. */ + ret = check_thread_quit_pipe(pollfd, revents); + if (ret) { + goto error; + } + + /* Event on the registration socket */ + if (pollfd == apps_sock) { + if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { + ERR("Register apps socket poll error"); + goto error; + } else if (revents & LPOLLIN) { ++ /* Registration starts here. Recording cycles */ ++ tracepoint(ust_register_start); ++ + 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; + } + + /* + * 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; + } + + 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); + + /* + * Wake the registration queue futex. Implicit memory + * barrier with the exchange in cds_wfq_enqueue. + */ + futex_nto1_wake(&ust_cmd_queue.futex); ++ ++ tracepoint(ust_register_stop); + } + } + } + } + + error: + 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); + + lttng_poll_clean(&events); + + return NULL; + } + + /* + * Start the thread_manage_consumer. This must be done after a lttng-consumerd + * exec or it will fails. + */ + static int spawn_consumer_thread(struct consumer_data *consumer_data) + { + int ret; + struct timespec timeout; + + timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT; + timeout.tv_nsec = 0; + + /* Setup semaphore */ + ret = sem_init(&consumer_data->sem, 0, 0); + if (ret < 0) { + PERROR("sem_init consumer semaphore"); + goto error; + } + + ret = pthread_create(&consumer_data->thread, NULL, + thread_manage_consumer, consumer_data); + if (ret != 0) { + PERROR("pthread_create consumer"); + ret = -1; + goto error; + } + + /* Get time for sem_timedwait absolute timeout */ + ret = clock_gettime(CLOCK_REALTIME, &timeout); + if (ret < 0) { + PERROR("clock_gettime spawn consumer"); + /* Infinite wait for the kconsumerd thread to be ready */ + ret = sem_wait(&consumer_data->sem); + } else { + /* Normal timeout if the gettime was successful */ + timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT; + ret = sem_timedwait(&consumer_data->sem, &timeout); + } + + if (ret < 0) { + if (errno == ETIMEDOUT) { + /* + * Call has timed out so we kill the kconsumerd_thread and return + * an error. + */ + ERR("The consumer thread was never ready. Killing it"); + ret = pthread_cancel(consumer_data->thread); + if (ret < 0) { + PERROR("pthread_cancel consumer thread"); + } + } else { + PERROR("semaphore wait failed consumer thread"); + } + goto error; + } + + pthread_mutex_lock(&consumer_data->pid_mutex); + if (consumer_data->pid == 0) { + ERR("Kconsumerd did not start"); + pthread_mutex_unlock(&consumer_data->pid_mutex); + goto error; + } + pthread_mutex_unlock(&consumer_data->pid_mutex); + + return 0; + + error: + return ret; + } + + /* + * Join consumer thread + */ + static int join_consumer_thread(struct consumer_data *consumer_data) + { + void *status; + int ret; + + if (consumer_data->pid != 0) { + ret = kill(consumer_data->pid, SIGTERM); + if (ret) { + ERR("Error killing consumer daemon"); + return ret; + } + return pthread_join(consumer_data->thread, &status); + } else { + return 0; + } + } + + /* + * Fork and exec a consumer daemon (consumerd). + * + * Return pid if successful else -1. + */ + static pid_t spawn_consumerd(struct consumer_data *consumer_data) + { + int ret; + pid_t pid; + const char *verbosity; + + DBG("Spawning consumerd"); + + pid = fork(); + if (pid == 0) { + /* + * Exec consumerd. + */ + if (opt_verbose > 1 || opt_verbose_consumer) { + verbosity = "--verbose"; + } else { + verbosity = "--quiet"; + } + switch (consumer_data->type) { + case LTTNG_CONSUMER_KERNEL: + execl(INSTALL_BIN_PATH "/lttng-consumerd", + "lttng-consumerd", verbosity, "-k", NULL); + break; + case LTTNG_CONSUMER_UST: + execl(INSTALL_BIN_PATH "/lttng-consumerd", + "lttng-consumerd", verbosity, "-u", NULL); + break; + default: + perror("unknown consumer type"); + exit(EXIT_FAILURE); + } + if (errno != 0) { + perror("kernel start consumer exec"); + } + exit(EXIT_FAILURE); + } else if (pid > 0) { + ret = pid; + } else { + perror("start consumer fork"); + ret = -errno; + } + return ret; + } + + /* + * Spawn the consumerd daemon and session daemon thread. + */ + static int start_consumerd(struct consumer_data *consumer_data) + { + int ret; + + pthread_mutex_lock(&consumer_data->pid_mutex); + if (consumer_data->pid != 0) { + pthread_mutex_unlock(&consumer_data->pid_mutex); + goto end; + } + + ret = spawn_consumerd(consumer_data); + if (ret < 0) { + ERR("Spawning consumerd failed"); + pthread_mutex_unlock(&consumer_data->pid_mutex); + goto error; + } + + /* Setting up the consumer_data pid */ + consumer_data->pid = ret; + DBG2("Consumer pid %d", consumer_data->pid); + pthread_mutex_unlock(&consumer_data->pid_mutex); + + DBG2("Spawning consumer control thread"); + ret = spawn_consumer_thread(consumer_data); + if (ret < 0) { + ERR("Fatal error spawning consumer control thread"); + goto error; + } + + end: + return 0; + + error: + return ret; + } + + /* + * modprobe_kernel_modules + */ + static int modprobe_kernel_modules(void) + { + int ret = 0, i; + char modprobe[256]; + + for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) { + ret = snprintf(modprobe, sizeof(modprobe), + "/sbin/modprobe %s%s", + kernel_modules_list[i].required ? "" : "-q ", + kernel_modules_list[i].name); + if (ret < 0) { + perror("snprintf modprobe"); + goto error; + } + modprobe[sizeof(modprobe) - 1] = '\0'; + ret = system(modprobe); + if (ret == -1) { + ERR("Unable to launch modprobe for module %s", + kernel_modules_list[i].name); + } else if (kernel_modules_list[i].required + && WEXITSTATUS(ret) != 0) { + ERR("Unable to load module %s", + kernel_modules_list[i].name); + } else { + DBG("Modprobe successfully %s", + kernel_modules_list[i].name); + } + } + + error: + return ret; + } + + /* + * mount_debugfs + */ + static int mount_debugfs(char *path) + { + int ret; + char *type = "debugfs"; + + ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid()); + if (ret < 0) { + PERROR("Cannot create debugfs path"); + goto error; + } + + ret = mount(type, path, type, 0, NULL); + if (ret < 0) { + PERROR("Cannot mount debugfs"); + goto error; + } + + DBG("Mounted debugfs successfully at %s", path); + + error: + return ret; + } + + /* + * Setup necessary data for kernel tracer action. + */ + static void init_kernel_tracer(void) + { + int ret; + char *proc_mounts = "/proc/mounts"; + char line[256]; + char *debugfs_path = NULL, *lttng_path = NULL; + FILE *fp; + + /* Detect debugfs */ + fp = fopen(proc_mounts, "r"); + if (fp == NULL) { + ERR("Unable to probe %s", proc_mounts); + goto error; + } + + while (fgets(line, sizeof(line), fp) != NULL) { + if (strstr(line, "debugfs") != NULL) { + /* Remove first string */ + strtok(line, " "); + /* Dup string here so we can reuse line later on */ + debugfs_path = strdup(strtok(NULL, " ")); + DBG("Got debugfs path : %s", debugfs_path); + break; + } + } + + fclose(fp); + + /* Mount debugfs if needded */ + if (debugfs_path == NULL) { + ret = asprintf(&debugfs_path, "/mnt/debugfs"); + if (ret < 0) { + perror("asprintf debugfs path"); + goto error; + } + ret = mount_debugfs(debugfs_path); + if (ret < 0) { + perror("Cannot mount debugfs"); + goto error; + } + } + + /* Modprobe lttng kernel modules */ + ret = modprobe_kernel_modules(); + if (ret < 0) { + goto error; + } + + /* Setup lttng kernel path */ + ret = asprintf(<tng_path, "%s/lttng", debugfs_path); + if (ret < 0) { + perror("asprintf lttng path"); + goto error; + } + + /* Open debugfs lttng */ + kernel_tracer_fd = open(lttng_path, O_RDWR); + if (kernel_tracer_fd < 0) { + DBG("Failed to open %s", lttng_path); + goto error; + } + + free(lttng_path); + free(debugfs_path); + DBG("Kernel tracer fd %d", kernel_tracer_fd); + return; + + error: + if (lttng_path) { + free(lttng_path); + } + if (debugfs_path) { + free(debugfs_path); + } + WARN("No kernel tracer available"); + kernel_tracer_fd = 0; + return; + } + + /* + * Init tracing by creating trace directory and sending fds kernel consumer. + */ + static int init_kernel_tracing(struct ltt_kernel_session *session) + { + int ret = 0; + + if (session->consumer_fds_sent == 0) { + /* + * Assign default kernel consumer socket if no consumer assigned to the + * kernel session. At this point, it's NOT suppose to be 0 but this is + * an extra security check. + */ + if (session->consumer_fd == 0) { + session->consumer_fd = kconsumer_data.cmd_sock; + } + + ret = send_kconsumer_session_streams(&kconsumer_data, session); + if (ret < 0) { + ret = LTTCOMM_KERN_CONSUMER_FAIL; + goto error; + } + + session->consumer_fds_sent = 1; + } + + error: + return ret; + } + + /* + * Create an UST session and add it to the session ust list. + */ + static int create_ust_session(struct ltt_session *session, + struct lttng_domain *domain) + { + int ret; + unsigned int uid; + struct ltt_ust_session *lus = NULL; + + switch (domain->type) { + case LTTNG_DOMAIN_UST: + break; + default: + ret = LTTCOMM_UNKNOWN_DOMAIN; + goto error; + } + + DBG("Creating UST session"); + + session_lock_list(); + uid = session_list_ptr->count; + session_unlock_list(); + + lus = trace_ust_create_session(session->path, uid, domain); + if (lus == NULL) { + ret = LTTCOMM_UST_SESS_FAIL; + goto error; + } + + ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG, + geteuid(), allowed_group()); + if (ret < 0) { + if (ret != -EEXIST) { + ERR("Trace directory creation error"); + ret = LTTCOMM_UST_SESS_FAIL; + goto error; + } + } + + /* The domain type dictate different actions on session creation */ + switch (domain->type) { + case LTTNG_DOMAIN_UST: + /* No ustctl for the global UST domain */ + break; + default: + goto error; + } + session->ust_session = lus; + + return LTTCOMM_OK; + + error: + free(lus); + return ret; + } + + /* + * Create a kernel tracer session then create the default channel. + */ + static int create_kernel_session(struct ltt_session *session) + { + int ret; + + DBG("Creating kernel session"); + + ret = kernel_create_session(session, kernel_tracer_fd); + if (ret < 0) { + ret = LTTCOMM_KERN_SESS_FAIL; + goto error; + } + + /* Set kernel consumer socket fd */ + if (kconsumer_data.cmd_sock) { + session->kernel_session->consumer_fd = kconsumer_data.cmd_sock; + } + + ret = mkdir_recursive(session->kernel_session->trace_path, + S_IRWXU | S_IRWXG, geteuid(), allowed_group()); + if (ret < 0) { + if (ret != -EEXIST) { + ERR("Trace directory creation error"); + goto error; + } + } + + error: + return ret; + } + + /* + * Using the session list, filled a lttng_session array to send back to the + * client for session listing. + * + * The session list lock MUST be acquired before calling this function. Use + * session_lock_list() and session_unlock_list(). + */ + static void list_lttng_sessions(struct lttng_session *sessions) + { + int i = 0; + struct ltt_session *session; + + DBG("Getting all available session"); + /* + * Iterate over session list and append data after the control struct in + * the buffer. + */ + cds_list_for_each_entry(session, &session_list_ptr->head, list) { + strncpy(sessions[i].path, session->path, PATH_MAX); + sessions[i].path[PATH_MAX - 1] = '\0'; + strncpy(sessions[i].name, session->name, NAME_MAX); + sessions[i].name[NAME_MAX - 1] = '\0'; + i++; + } + } + + /* + * Fill lttng_channel array of all channels. + */ + static void list_lttng_channels(struct ltt_session *session, + struct lttng_channel *channels) + { + int i = 0; + struct ltt_kernel_channel *kchan; + + DBG("Listing channels for session %s", session->name); + + /* Kernel channels */ + if (session->kernel_session != NULL) { + cds_list_for_each_entry(kchan, + &session->kernel_session->channel_list.head, list) { + /* Copy lttng_channel struct to array */ + memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel)); + channels[i].enabled = kchan->enabled; + i++; + } + } + + /* TODO: Missing UST listing */ + } + + /* + * Fill lttng_event array of all events in the channel. + */ + static void list_lttng_events(struct ltt_kernel_channel *kchan, + struct lttng_event *events) + { + /* + * TODO: This is ONLY kernel. Need UST support. + */ + int i = 0; + struct ltt_kernel_event *event; + + DBG("Listing events for channel %s", kchan->channel->name); + + /* Kernel channels */ + cds_list_for_each_entry(event, &kchan->events_list.head , list) { + strncpy(events[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN); + events[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; + events[i].enabled = event->enabled; + switch (event->event->instrumentation) { + case LTTNG_KERNEL_TRACEPOINT: + events[i].type = LTTNG_EVENT_TRACEPOINT; + break; + case LTTNG_KERNEL_KPROBE: + case LTTNG_KERNEL_KRETPROBE: + events[i].type = LTTNG_EVENT_PROBE; + memcpy(&events[i].attr.probe, &event->event->u.kprobe, + sizeof(struct lttng_kernel_kprobe)); + break; + case LTTNG_KERNEL_FUNCTION: + events[i].type = LTTNG_EVENT_FUNCTION; + memcpy(&events[i].attr.ftrace, &event->event->u.ftrace, + sizeof(struct lttng_kernel_function)); + break; + case LTTNG_KERNEL_NOOP: + events[i].type = LTTNG_EVENT_NOOP; + break; + case LTTNG_KERNEL_SYSCALL: + events[i].type = LTTNG_EVENT_SYSCALL; + break; + case LTTNG_KERNEL_ALL: + assert(0); + break; + } + i++; + } + } + + /* + * Command LTTNG_DISABLE_CHANNEL processed by the client thread. + */ + static int cmd_disable_channel(struct ltt_session *session, + int domain, char *channel_name) + { + int ret; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + ret = channel_kernel_disable(session->kernel_session, + channel_name); + if (ret != LTTCOMM_OK) { + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + break; + case LTTNG_DOMAIN_UST_PID: + break; + default: + ret = LTTCOMM_UNKNOWN_DOMAIN; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Copy channel from attributes and set it in the application channel list. + */ + /* + static int copy_ust_channel_to_app(struct ltt_ust_session *usess, + struct lttng_channel *attr, struct ust_app *app) + { + int ret; + struct ltt_ust_channel *uchan, *new_chan; + + uchan = trace_ust_get_channel_by_key(usess->channels, attr->name); + if (uchan == NULL) { + ret = LTTCOMM_FATAL; + goto error; + } + + new_chan = trace_ust_create_channel(attr, usess->path); + if (new_chan == NULL) { + PERROR("malloc ltt_ust_channel"); + ret = LTTCOMM_FATAL; + goto error; + } + + ret = channel_ust_copy(new_chan, uchan); + if (ret < 0) { + ret = LTTCOMM_FATAL; + goto error; + } + + error: + return ret; + } + */ + + /* + * Command LTTNG_ENABLE_CHANNEL processed by the client thread. + */ + static int cmd_enable_channel(struct ltt_session *session, + struct lttng_domain *domain, struct lttng_channel *attr) + { + int ret; + struct ltt_ust_session *usess = session->ust_session; + + DBG("Enabling channel %s for session %s", session->name, attr->name); + + switch (domain->type) { + case LTTNG_DOMAIN_KERNEL: + { + struct ltt_kernel_channel *kchan; + + kchan = trace_kernel_get_channel_by_name(attr->name, + session->kernel_session); + if (kchan == NULL) { + ret = channel_kernel_create(session->kernel_session, + attr, kernel_poll_pipe[1]); + } else { + ret = channel_kernel_enable(session->kernel_session, kchan); + } + + if (ret != LTTCOMM_OK) { + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + break; + } + case LTTNG_DOMAIN_UST: + { + struct ltt_ust_channel *uchan; + + DBG2("Enabling channel for LTTNG_DOMAIN_UST"); + + /* Get channel in global UST domain HT */ + uchan = trace_ust_find_channel_by_name(usess->domain_global.channels, + attr->name); + if (uchan == NULL) { + uchan = trace_ust_create_channel(attr, usess->pathname); + if (uchan == NULL) { + ret = LTTCOMM_UST_CHAN_FAIL; + goto error; + } + rcu_read_lock(); + hashtable_add_unique(usess->domain_global.channels, &uchan->node); + rcu_read_unlock(); + DBG2("UST channel %s added to global domain HT", attr->name); + } else { + ret = LTTCOMM_UST_CHAN_EXIST; + goto error; + } + + ret = ust_app_add_channel(usess, uchan); + if (ret != LTTCOMM_OK) { + goto error; + } + + break; + } + case LTTNG_DOMAIN_UST_PID: + { + /* + int sock; + struct ltt_ust_channel *uchan; + struct ltt_ust_session *usess; + struct ust_app *app; + + usess = trace_ust_get_session_by_pid(&session->ust_session_list, + domain->attr.pid); + if (usess == NULL) { + ret = LTTCOMM_UST_CHAN_NOT_FOUND; + goto error; + } + + app = ust_app_get_by_pid(domain->attr.pid); + if (app == NULL) { + ret = LTTCOMM_APP_NOT_FOUND; + goto error; + } + sock = app->sock; + + uchan = trace_ust_get_channel_by_name(attr->name, usess); + if (uchan == NULL) { + ret = channel_ust_create(usess, attr, sock); + } else { + ret = channel_ust_enable(usess, uchan, sock); + } + + if (ret != LTTCOMM_OK) { + goto error; + } + + ret = copy_ust_channel_to_app(usess, attr, app); + if (ret != LTTCOMM_OK) { + goto error; + } + + DBG("UST channel %s created for app sock %d with pid %d", + attr->name, app->sock, domain->attr.pid); + */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + default: + ret = LTTCOMM_UNKNOWN_DOMAIN; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_DISABLE_EVENT processed by the client thread. + */ + static int cmd_disable_event(struct ltt_session *session, int domain, + char *channel_name, char *event_name) + { + int ret; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + { + struct ltt_kernel_channel *kchan; + + kchan = trace_kernel_get_channel_by_name(channel_name, + session->kernel_session); + if (kchan == NULL) { + ret = LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } + + ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name); + if (ret != LTTCOMM_OK) { + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + break; + } + case LTTNG_DOMAIN_UST: + case LTTNG_DOMAIN_UST_EXEC_NAME: + case LTTNG_DOMAIN_UST_PID: + case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN: + default: + /* TODO: Other UST domains */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread. + */ + static int cmd_disable_event_all(struct ltt_session *session, int domain, + char *channel_name) + { + int ret; + struct ltt_kernel_channel *kchan; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + kchan = trace_kernel_get_channel_by_name(channel_name, + session->kernel_session); + if (kchan == NULL) { + ret = LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } + + ret = event_kernel_disable_all(session->kernel_session, kchan); + if (ret != LTTCOMM_OK) { + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + break; + default: + /* TODO: Userspace tracing */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_ADD_CONTEXT processed by the client thread. + */ + static int cmd_add_context(struct ltt_session *session, int domain, + char *channel_name, char *event_name, struct lttng_event_context *ctx) + { + int ret; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + /* Add kernel context to kernel tracer */ + ret = context_kernel_add(session->kernel_session, ctx, + event_name, channel_name); + if (ret != LTTCOMM_OK) { + goto error; + } + break; + case LTTNG_DOMAIN_UST: + { + /* + struct ltt_ust_session *usess; + + cds_list_for_each_entry(usess, &session->ust_session_list.head, list) { + ret = context_ust_add(usess, ctx, + event_name, channel_name, domain); + if (ret != LTTCOMM_OK) { + goto error; + } + } + break; + */ + } + default: + /* TODO: UST other domains */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_ENABLE_EVENT processed by the client thread. + */ + static int cmd_enable_event(struct ltt_session *session, int domain, + char *channel_name, struct lttng_event *event) + { + int ret; + struct lttng_channel *attr; + struct ltt_ust_session *usess = session->ust_session; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + { + struct ltt_kernel_channel *kchan; + + kchan = trace_kernel_get_channel_by_name(channel_name, + session->kernel_session); + if (kchan == NULL) { + attr = channel_new_default_attr(domain); + if (attr == NULL) { + ret = LTTCOMM_FATAL; + goto error; + } + snprintf(attr->name, NAME_MAX, "%s", channel_name); + + /* This call will notify the kernel thread */ + ret = channel_kernel_create(session->kernel_session, + attr, kernel_poll_pipe[1]); + if (ret != LTTCOMM_OK) { + goto error; + } + } + + /* Get the newly created kernel channel pointer */ + kchan = trace_kernel_get_channel_by_name(channel_name, + session->kernel_session); + if (kchan == NULL) { + /* This sould not happen... */ + ret = LTTCOMM_FATAL; + goto error; + } + + ret = event_kernel_enable_tracepoint(session->kernel_session, kchan, + event); + if (ret != LTTCOMM_OK) { + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + break; + } + case LTTNG_DOMAIN_UST: + { + struct ltt_ust_channel *uchan; + struct ltt_ust_event *uevent; + + uchan = trace_ust_find_channel_by_name(usess->domain_global.channels, + channel_name); + if (uchan == NULL) { + /* TODO: Create default channel */ + ret = LTTCOMM_UST_CHAN_NOT_FOUND; + goto error; + } + + uevent = trace_ust_find_event_by_name(uchan->events, event->name); + if (uevent == NULL) { + uevent = trace_ust_create_event(event); + if (uevent == NULL) { + ret = LTTCOMM_FATAL; + goto error; + } + } + + ret = ust_app_add_event(usess, uchan, uevent); + if (ret < 0) { + ret = LTTCOMM_UST_ENABLE_FAIL; + goto error; + } + break; + } + case LTTNG_DOMAIN_UST_EXEC_NAME: + case LTTNG_DOMAIN_UST_PID: + case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN: + default: + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread. + */ + static int cmd_enable_event_all(struct ltt_session *session, int domain, + char *channel_name, int event_type) + { + int ret; + struct ltt_kernel_channel *kchan; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + kchan = trace_kernel_get_channel_by_name(channel_name, + session->kernel_session); + if (kchan == NULL) { + /* This call will notify the kernel thread */ + ret = channel_kernel_create(session->kernel_session, NULL, + kernel_poll_pipe[1]); + if (ret != LTTCOMM_OK) { + goto error; + } + } + + /* Get the newly created kernel channel pointer */ + kchan = trace_kernel_get_channel_by_name(channel_name, + session->kernel_session); + if (kchan == NULL) { + /* This sould not happen... */ + ret = LTTCOMM_FATAL; + goto error; + } + + switch (event_type) { + case LTTNG_KERNEL_SYSCALL: + ret = event_kernel_enable_all_syscalls(session->kernel_session, + kchan, kernel_tracer_fd); + break; + case LTTNG_KERNEL_TRACEPOINT: + /* + * This call enables all LTTNG_KERNEL_TRACEPOINTS and + * events already registered to the channel. + */ + ret = event_kernel_enable_all_tracepoints(session->kernel_session, + kchan, kernel_tracer_fd); + break; + case LTTNG_KERNEL_ALL: + /* Enable syscalls and tracepoints */ + ret = event_kernel_enable_all(session->kernel_session, + kchan, kernel_tracer_fd); + break; + default: + ret = LTTCOMM_KERN_ENABLE_FAIL; + goto error; + } + if (ret != LTTCOMM_OK) { + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + break; + default: + /* TODO: Userspace tracing */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_LIST_TRACEPOINTS processed by the client thread. + */ + static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events) + { + int ret; + ssize_t nb_events = 0; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + nb_events = kernel_list_events(kernel_tracer_fd, events); + if (nb_events < 0) { + ret = LTTCOMM_KERN_LIST_FAIL; + goto error; + } + break; + default: + /* TODO: Userspace listing */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + return nb_events; + + error: + /* Return negative value to differentiate return code */ + return -ret; + } + + /* + * Command LTTNG_START_TRACE processed by the client thread. + */ + static int cmd_start_trace(struct ltt_session *session) + { + int ret; + struct ltt_kernel_session *ksession; + struct ltt_ust_session *usess = session->ust_session; + + /* Short cut */ + ksession = session->kernel_session; + + /* Kernel tracing */ + if (ksession != NULL) { + struct ltt_kernel_channel *kchan; + + /* Open kernel metadata */ + if (ksession->metadata == NULL) { + ret = kernel_open_metadata(ksession, ksession->trace_path); + if (ret < 0) { + ret = LTTCOMM_KERN_META_FAIL; + goto error; + } + } + + /* Open kernel metadata stream */ + if (ksession->metadata_stream_fd == 0) { + ret = kernel_open_metadata_stream(ksession); + if (ret < 0) { + ERR("Kernel create metadata stream failed"); + ret = LTTCOMM_KERN_STREAM_FAIL; + goto error; + } + } + + /* For each channel */ + cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) { + if (kchan->stream_count == 0) { + ret = kernel_open_channel_stream(kchan); + if (ret < 0) { + ret = LTTCOMM_KERN_STREAM_FAIL; + goto error; + } + /* Update the stream global counter */ + ksession->stream_count_global += ret; + } + } + + /* Setup kernel consumer socket and send fds to it */ + ret = init_kernel_tracing(ksession); + if (ret < 0) { + ret = LTTCOMM_KERN_START_FAIL; + goto error; + } + + /* This start the kernel tracing */ + ret = kernel_start_session(ksession); + if (ret < 0) { + ret = LTTCOMM_KERN_START_FAIL; + goto error; + } + + /* Quiescent wait after starting trace */ + kernel_wait_quiescent(kernel_tracer_fd); + } + + ret = ust_app_start_trace(usess); + if (ret < 0) { + ret = LTTCOMM_UST_START_FAIL; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_STOP_TRACE processed by the client thread. + */ + static int cmd_stop_trace(struct ltt_session *session) + { + int ret; + struct ltt_kernel_channel *kchan; + struct ltt_kernel_session *ksession; + //struct ltt_ust_session *usess; + //struct ltt_ust_channel *ustchan; + + /* Short cut */ + ksession = session->kernel_session; + + /* Kernel tracer */ + if (ksession != NULL) { + DBG("Stop kernel tracing"); + + /* Flush all buffers before stopping */ + ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd); + if (ret < 0) { + ERR("Kernel metadata flush failed"); + } + + cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) { + ret = kernel_flush_buffer(kchan); + if (ret < 0) { + ERR("Kernel flush buffer error"); + } + } + + ret = kernel_stop_session(ksession); + if (ret < 0) { + ret = LTTCOMM_KERN_STOP_FAIL; + goto error; + } + + kernel_wait_quiescent(kernel_tracer_fd); + } + + #ifdef DISABLE + /* Stop each UST session */ + DBG("Stop UST tracing"); + cds_list_for_each_entry(usess, &session->ust_session_list.head, list) { + /* Flush all buffers before stopping */ + ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj); + if (ret < 0) { + ERR("UST metadata flush failed"); + } + + cds_list_for_each_entry(ustchan, &usess->channels.head, list) { + ret = ustctl_flush_buffer(usess->sock, ustchan->obj); + if (ret < 0) { + ERR("UST flush buffer error"); + } + } + + ret = ustctl_stop_session(usess->sock, usess->handle); + if (ret < 0) { + ret = LTTCOMM_KERN_STOP_FAIL; + goto error; + } + + ustctl_wait_quiescent(usess->sock); + } + #endif + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_CREATE_SESSION processed by the client thread. + */ + static int cmd_create_session(char *name, char *path) + { + int ret; + + ret = session_create(name, path); + if (ret != LTTCOMM_OK) { + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_DESTROY_SESSION processed by the client thread. + */ + static int cmd_destroy_session(struct ltt_session *session, char *name) + { + int ret; + + /* Clean kernel session teardown */ + teardown_kernel_session(session); + + /* + * Must notify the kernel thread here to update it's poll setin order + * to remove the channel(s)' fd just destroyed. + */ + ret = notify_thread_pipe(kernel_poll_pipe[1]); + if (ret < 0) { + perror("write kernel poll pipe"); + } + + ret = session_destroy(session); + + return ret; + } + + /* + * Command LTTNG_CALIBRATE processed by the client thread. + */ + static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate) + { + int ret; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + { + struct lttng_kernel_calibrate kcalibrate; + + kcalibrate.type = calibrate->type; + ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate); + if (ret < 0) { + ret = LTTCOMM_KERN_ENABLE_FAIL; + goto error; + } + break; + } + default: + /* TODO: Userspace tracing */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_REGISTER_CONSUMER processed by the client thread. + */ + static int cmd_register_consumer(struct ltt_session *session, int domain, + char *sock_path) + { + int ret, sock; + + switch (domain) { + case LTTNG_DOMAIN_KERNEL: + /* Can't register a consumer if there is already one */ + if (session->kernel_session->consumer_fd != 0) { + ret = LTTCOMM_KERN_CONSUMER_FAIL; + goto error; + } + + sock = lttcomm_connect_unix_sock(sock_path); + if (sock < 0) { + ret = LTTCOMM_CONNECT_FAIL; + goto error; + } + + session->kernel_session->consumer_fd = sock; + break; + default: + /* TODO: Userspace tracing */ + ret = LTTCOMM_NOT_IMPLEMENTED; + goto error; + } + + ret = LTTCOMM_OK; + + error: + return ret; + } + + /* + * Command LTTNG_LIST_DOMAINS processed by the client thread. + */ + static ssize_t cmd_list_domains(struct ltt_session *session, + struct lttng_domain **domains) + { + int ret; + ssize_t nb_dom = 0; + + if (session->kernel_session != NULL) { + nb_dom++; + } + + /* TODO: User-space tracer domain support */ + + *domains = malloc(nb_dom * sizeof(struct lttng_domain)); + if (*domains == NULL) { + ret = -LTTCOMM_FATAL; + goto error; + } + + (*domains)[0].type = LTTNG_DOMAIN_KERNEL; + + return nb_dom; + + error: + return ret; + } + + /* + * Command LTTNG_LIST_CHANNELS processed by the client thread. + */ + static ssize_t cmd_list_channels(struct ltt_session *session, + struct lttng_channel **channels) + { + int ret; + ssize_t nb_chan = 0; + + if (session->kernel_session != NULL) { + nb_chan += session->kernel_session->channel_count; + } + + *channels = malloc(nb_chan * sizeof(struct lttng_channel)); + if (*channels == NULL) { + ret = -LTTCOMM_FATAL; + goto error; + } + + list_lttng_channels(session, *channels); + + /* TODO UST support */ + + return nb_chan; + + error: + return ret; + } + + /* + * Command LTTNG_LIST_EVENTS processed by the client thread. + */ + static ssize_t cmd_list_events(struct ltt_session *session, + char *channel_name, struct lttng_event **events) + { + int ret; + ssize_t nb_event = 0; + struct ltt_kernel_channel *kchan = NULL; + + if (session->kernel_session != NULL) { + kchan = trace_kernel_get_channel_by_name(channel_name, + session->kernel_session); + if (kchan == NULL) { + ret = -LTTCOMM_KERN_CHAN_NOT_FOUND; + goto error; + } + nb_event += kchan->event_count; + } + + *events = malloc(nb_event * sizeof(struct lttng_event)); + if (*events == NULL) { + ret = -LTTCOMM_FATAL; + goto error; + } + + list_lttng_events(kchan, *events); + + /* TODO: User-space tracer support */ + + return nb_event; + + error: + return ret; + } + + /* + * Process the command requested by the lttng client within the command + * context structure. This function make sure that the return structure (llm) + * is set and ready for transmission before returning. + * + * Return any error encountered or 0 for success. + */ + static int process_client_msg(struct command_ctx *cmd_ctx) + { + int ret = LTTCOMM_OK; + int need_tracing_session = 1; + + DBG("Processing client command %d", cmd_ctx->lsm->cmd_type); + + /* + * Check for command that don't needs to allocate a returned payload. We do + * this here so we don't have to make the call for no payload at each + * command. + */ + switch(cmd_ctx->lsm->cmd_type) { + case LTTNG_LIST_SESSIONS: + case LTTNG_LIST_TRACEPOINTS: + case LTTNG_LIST_DOMAINS: + case LTTNG_LIST_CHANNELS: + case LTTNG_LIST_EVENTS: + break; + default: + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + /* This label does not try to unlock the session */ + goto init_setup_error; + } + } + + /* Commands that DO NOT need a session. */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_CALIBRATE: + case LTTNG_CREATE_SESSION: + case LTTNG_LIST_SESSIONS: + case LTTNG_LIST_TRACEPOINTS: + need_tracing_session = 0; + break; + default: + DBG("Getting session %s by name", cmd_ctx->lsm->session.name); + session_lock_list(); + cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name); + session_unlock_list(); + if (cmd_ctx->session == NULL) { + if (cmd_ctx->lsm->session.name != NULL) { + ret = LTTCOMM_SESS_NOT_FOUND; + } else { + /* If no session name specified */ + ret = LTTCOMM_SELECT_SESS; + } + goto error; + } else { + /* Acquire lock for the session */ + session_lock(cmd_ctx->session); + } + break; + } + + /* + * Check domain type for specific "pre-action". + */ + switch (cmd_ctx->lsm->domain.type) { + case LTTNG_DOMAIN_KERNEL: + /* Kernel tracer check */ + if (kernel_tracer_fd == 0) { + /* Basically, load kernel tracer modules */ + init_kernel_tracer(); + if (kernel_tracer_fd == 0) { + ret = LTTCOMM_KERN_NA; + goto error; + } + } + + /* Need a session for kernel command */ + if (need_tracing_session) { + if (cmd_ctx->session->kernel_session == NULL) { + ret = create_kernel_session(cmd_ctx->session); + if (ret < 0) { + ret = LTTCOMM_KERN_SESS_FAIL; + goto error; + } + } + + /* Start the kernel consumer daemon */ + pthread_mutex_lock(&kconsumer_data.pid_mutex); + if (kconsumer_data.pid == 0 && + cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { + pthread_mutex_unlock(&kconsumer_data.pid_mutex); + ret = start_consumerd(&kconsumer_data); + if (ret < 0) { + ret = LTTCOMM_KERN_CONSUMER_FAIL; + goto error; + } + } + pthread_mutex_unlock(&kconsumer_data.pid_mutex); + } + break; + case LTTNG_DOMAIN_UST: + { + if (need_tracing_session) { + if (cmd_ctx->session->ust_session == NULL) { + ret = create_ust_session(cmd_ctx->session, + &cmd_ctx->lsm->domain); + if (ret != LTTCOMM_OK) { + goto error; + } + } + /* Start the kernel consumer daemon */ + pthread_mutex_lock(&ustconsumer_data.pid_mutex); + if (ustconsumer_data.pid == 0 && + cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) { + pthread_mutex_unlock(&ustconsumer_data.pid_mutex); + ret = start_consumerd(&ustconsumer_data); + if (ret < 0) { + ret = LTTCOMM_KERN_CONSUMER_FAIL; + goto error; + } + + cmd_ctx->session->ust_session->consumer_fd = + ustconsumer_data.cmd_sock; + } + pthread_mutex_unlock(&ustconsumer_data.pid_mutex); + } + break; + } + default: + break; + } + + /* Process by command type */ + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_ADD_CONTEXT: + { + ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.context.channel_name, + cmd_ctx->lsm->u.context.event_name, + &cmd_ctx->lsm->u.context.ctx); + break; + } + case LTTNG_DISABLE_CHANNEL: + { + ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.disable.channel_name); + break; + } + case LTTNG_DISABLE_EVENT: + { + ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.disable.channel_name, + cmd_ctx->lsm->u.disable.name); + ret = LTTCOMM_OK; + break; + } + case LTTNG_DISABLE_ALL_EVENT: + { + DBG("Disabling all events"); + + ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.disable.channel_name); + break; + } + case LTTNG_ENABLE_CHANNEL: + { + ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain, + &cmd_ctx->lsm->u.channel.chan); + break; + } + case LTTNG_ENABLE_EVENT: + { + ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.enable.channel_name, + &cmd_ctx->lsm->u.enable.event); + break; + } + case LTTNG_ENABLE_ALL_EVENT: + { + DBG("Enabling all events"); + + ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.enable.channel_name, + cmd_ctx->lsm->u.enable.event.type); + break; + } + case LTTNG_LIST_TRACEPOINTS: + { + struct lttng_event *events; + ssize_t nb_events; + + nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events); + if (nb_events < 0) { + ret = -nb_events; + goto error; + } + + /* + * Setup lttng message with payload size set to the event list size in + * bytes and then copy list into the llm payload. + */ + ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events); + if (ret < 0) { + free(events); + goto setup_error; + } + + /* Copy event list into message payload */ + memcpy(cmd_ctx->llm->payload, events, + sizeof(struct lttng_event) * nb_events); + + free(events); + + ret = LTTCOMM_OK; + break; + } + case LTTNG_START_TRACE: + { + ret = cmd_start_trace(cmd_ctx->session); + break; + } + case LTTNG_STOP_TRACE: + { + ret = cmd_stop_trace(cmd_ctx->session); + break; + } + case LTTNG_CREATE_SESSION: + { ++ tracepoint(create_session_start); + ret = cmd_create_session(cmd_ctx->lsm->session.name, + cmd_ctx->lsm->session.path); ++ tracepoint(create_session_end); + break; + } + case LTTNG_DESTROY_SESSION: + { ++ tracepoint(destroy_session_start); + ret = cmd_destroy_session(cmd_ctx->session, + cmd_ctx->lsm->session.name); ++ tracepoint(destroy_session_end); + break; + } + case LTTNG_LIST_DOMAINS: + { + ssize_t nb_dom; + struct lttng_domain *domains; + + nb_dom = cmd_list_domains(cmd_ctx->session, &domains); + if (nb_dom < 0) { + ret = -nb_dom; + goto error; + } + + ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain)); + if (ret < 0) { + goto setup_error; + } + + /* Copy event list into message payload */ + memcpy(cmd_ctx->llm->payload, domains, + nb_dom * sizeof(struct lttng_domain)); + + free(domains); + + ret = LTTCOMM_OK; + break; + } + case LTTNG_LIST_CHANNELS: + { + size_t nb_chan; + struct lttng_channel *channels; + + nb_chan = cmd_list_channels(cmd_ctx->session, &channels); + if (nb_chan < 0) { + ret = -nb_chan; + goto error; + } + + ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel)); + if (ret < 0) { + goto setup_error; + } + + /* Copy event list into message payload */ + memcpy(cmd_ctx->llm->payload, channels, + nb_chan * sizeof(struct lttng_channel)); + + free(channels); + + ret = LTTCOMM_OK; + break; + } + case LTTNG_LIST_EVENTS: + { + size_t nb_event; + struct lttng_event *events = NULL; + + nb_event = cmd_list_events(cmd_ctx->session, + cmd_ctx->lsm->u.list.channel_name, &events); + if (nb_event < 0) { + ret = -nb_event; + goto error; + } + + ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event)); + if (ret < 0) { + goto setup_error; + } + + /* Copy event list into message payload */ + memcpy(cmd_ctx->llm->payload, events, + nb_event * sizeof(struct lttng_event)); + + free(events); + + ret = LTTCOMM_OK; + break; + } + case LTTNG_LIST_SESSIONS: + { + session_lock_list(); + + if (session_list_ptr->count == 0) { + ret = LTTCOMM_NO_SESSION; + session_unlock_list(); + goto error; + } + + ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * + session_list_ptr->count); + if (ret < 0) { + session_unlock_list(); + goto setup_error; + } + + /* Filled the session array */ + list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload)); + + session_unlock_list(); + + ret = LTTCOMM_OK; + break; + } + case LTTNG_CALIBRATE: + { + ret = cmd_calibrate(cmd_ctx->lsm->domain.type, + &cmd_ctx->lsm->u.calibrate); + break; + } + case LTTNG_REGISTER_CONSUMER: + { + ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type, + cmd_ctx->lsm->u.reg.path); + break; + } + default: + ret = LTTCOMM_UND; + break; + } + + error: + if (cmd_ctx->llm == NULL) { + DBG("Missing llm structure. Allocating one."); + if (setup_lttng_msg(cmd_ctx, 0) < 0) { + goto setup_error; + } + } + /* Set return code */ + cmd_ctx->llm->ret_code = ret; + setup_error: + if (cmd_ctx->session) { + session_unlock(cmd_ctx->session); + } + init_setup_error: + return ret; + } + + /* + * This thread manage all clients request using the unix client socket for + * communication. + */ + static void *thread_manage_clients(void *data) + { + int sock = 0, ret, i, pollfd; + uint32_t revents, nb_fd; + struct command_ctx *cmd_ctx = NULL; + struct lttng_poll_event events; + ++ tracepoint(sessiond_th_cli_start); ++ + DBG("[thread] Manage client started"); + + rcu_register_thread(); + + ret = lttcomm_listen_unix_sock(client_sock); + if (ret < 0) { + goto error; + } + + /* + * Pass 2 as size here for the thread quit pipe and client_sock. Nothing + * more will be added to this poll set. + */ + ret = create_thread_poll_set(&events, 2); + if (ret < 0) { + goto error; + } + + /* Add the application registration socket */ + ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI); + if (ret < 0) { + goto error; + } + + /* + * Notify parent pid that we are ready to accept command for client side. + */ + if (opt_sig_parent) { + kill(ppid, SIGCHLD); + } + + while (1) { + DBG("Accepting client command ..."); + ++ tracepoint(sessiond_th_cli_poll); ++ + nb_fd = LTTNG_POLL_GETNB(&events); + + /* Inifinite blocking call, waiting for transmission */ + ret = lttng_poll_wait(&events, -1); + if (ret < 0) { + goto error; + } + + for (i = 0; i < nb_fd; i++) { + /* Fetch once the poll data */ + revents = LTTNG_POLL_GETEV(&events, i); + pollfd = LTTNG_POLL_GETFD(&events, i); + + /* Thread quit pipe has been closed. Killing thread. */ + ret = check_thread_quit_pipe(pollfd, revents); + if (ret) { + goto error; + } + + /* Event on the registration socket */ + if (pollfd == client_sock) { + if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { + ERR("Client socket poll error"); + goto error; + } + } + } + + DBG("Wait for client response"); + + 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)); + if (cmd_ctx == NULL) { + perror("malloc cmd_ctx"); + goto error; + } + + /* Allocate data buffer for reception */ + cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg)); + if (cmd_ctx->lsm == NULL) { + perror("malloc cmd_ctx->lsm"); + goto error; + } + + 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) { + DBG("Nothing recv() from client... continuing"); + close(sock); + free(cmd_ctx); + continue; + } + + // TODO: Validate cmd_ctx including sanity check for + // security purpose. + + rcu_thread_online(); + /* + * 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); + rcu_thread_offline(); + 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: %s)", + cmd_ctx->lttng_msg_size, + lttng_strerror(-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); + + /* End of transmission */ + close(sock); + } + + error: + DBG("Client thread dying"); + unlink(client_unix_sock_path); + close(client_sock); + close(sock); + + lttng_poll_clean(&events); + clean_command_ctx(&cmd_ctx); + + rcu_unregister_thread(); + return NULL; + } + + + /* + * usage function on stderr + */ + static void usage(void) + { + fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname); + fprintf(stderr, " -h, --help Display this usage.\n"); + fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n"); + fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n"); + fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n"); + fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n"); + fprintf(stderr, " --ustconsumerd-err-sock PATH Specify path for the UST consumer error socket\n"); + fprintf(stderr, " --ustconsumerd-cmd-sock PATH Specify path for the UST consumer command socket\n"); + fprintf(stderr, " -d, --daemonize Start as a daemon.\n"); + fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n"); + fprintf(stderr, " -V, --version Show version number.\n"); + fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n"); + fprintf(stderr, " -q, --quiet No output at all.\n"); + fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n"); + fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n"); + } + + /* + * daemon argument parsing + */ + static int parse_args(int argc, char **argv) + { + int c; + + static struct option long_options[] = { + { "client-sock", 1, 0, 'c' }, + { "apps-sock", 1, 0, 'a' }, + { "kconsumerd-cmd-sock", 1, 0, 'C' }, + { "kconsumerd-err-sock", 1, 0, 'E' }, + { "ustconsumerd-cmd-sock", 1, 0, 'D' }, + { "ustconsumerd-err-sock", 1, 0, 'F' }, + { "daemonize", 0, 0, 'd' }, + { "sig-parent", 0, 0, 'S' }, + { "help", 0, 0, 'h' }, + { "group", 1, 0, 'g' }, + { "version", 0, 0, 'V' }, + { "quiet", 0, 0, 'q' }, + { "verbose", 0, 0, 'v' }, + { "verbose-consumer", 0, 0, 'Z' }, + { NULL, 0, 0, 0 } + }; + + while (1) { + int option_index = 0; + c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z", + long_options, &option_index); + if (c == -1) { + break; + } + + 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(client_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'a': + snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'd': + opt_daemon = 1; + break; + case 'g': + opt_tracing_group = strdup(optarg); + break; + case 'h': + usage(); + exit(EXIT_FAILURE); + case 'V': + fprintf(stdout, "%s\n", VERSION); + exit(EXIT_SUCCESS); + case 'S': + opt_sig_parent = 1; + break; + case 'E': + snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'C': + snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'F': + snprintf(ustconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'D': + snprintf(ustconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'q': + opt_quiet = 1; + break; + case 'v': + /* Verbose level can increase using multiple -v */ + opt_verbose += 1; + break; + case 'Z': + opt_verbose_consumer += 1; + break; + default: + /* Unknown option or other error. + * Error is printed by getopt, just return */ + return -1; + } + } + + return 0; + } + + /* + * Creates the two needed socket by the daemon. + * apps_sock - The communication socket for all UST apps. + * client_sock - The communication of the cli tool (lttng). + */ + static int init_daemon_socket(void) + { + int ret = 0; + mode_t old_umask; + + old_umask = umask(0); + + /* Create client tool unix socket */ + client_sock = lttcomm_create_unix_sock(client_unix_sock_path); + if (client_sock < 0) { + ERR("Create unix sock failed: %s", client_unix_sock_path); + ret = -1; + goto end; + } + + /* File permission MUST be 660 */ + ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); + if (ret < 0) { + ERR("Set file permissions failed: %s", client_unix_sock_path); + perror("chmod"); + goto end; + } + + /* Create the application unix socket */ + apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path); + if (apps_sock < 0) { + ERR("Create unix sock failed: %s", apps_unix_sock_path); + ret = -1; + goto end; + } + + /* File permission MUST be 666 */ + ret = chmod(apps_unix_sock_path, + S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); + if (ret < 0) { + ERR("Set file permissions failed: %s", apps_unix_sock_path); + perror("chmod"); + goto end; + } + + end: + umask(old_umask); + return ret; + } + + /* + * Check if the global socket is available, and if a daemon is answering at the + * other side. If yes, error is returned. + */ + static int check_existing_daemon(void) + { + if (access(client_unix_sock_path, F_OK) < 0 && + access(apps_unix_sock_path, F_OK) < 0) { + return 0; + } + + /* Is there anybody out there ? */ + if (lttng_session_daemon_alive()) { + return -EEXIST; + } else { + return 0; + } + } + + /* + * Set the tracing group gid onto the client socket. + * + * Race window between mkdir and chown is OK because we are going from more + * permissive (root.root) to les permissive (root.tracing). + */ + static int set_permissions(void) + { + int ret; + gid_t gid; + + gid = allowed_group(); + if (gid < 0) { + if (is_root) { + WARN("No tracing group detected"); + ret = 0; + } else { + ERR("Missing tracing group. Aborting execution."); + ret = -1; + } + goto end; + } + + /* Set lttng run dir */ + ret = chown(LTTNG_RUNDIR, 0, gid); + if (ret < 0) { + ERR("Unable to set group on " LTTNG_RUNDIR); + perror("chown"); + } + + /* lttng client socket path */ + ret = chown(client_unix_sock_path, 0, gid); + if (ret < 0) { + ERR("Unable to set group on %s", client_unix_sock_path); + perror("chown"); + } + + /* kconsumer error socket path */ + ret = chown(kconsumer_data.err_unix_sock_path, 0, gid); + if (ret < 0) { + ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path); + perror("chown"); + } + + /* ustconsumer error socket path */ + ret = chown(ustconsumer_data.err_unix_sock_path, 0, gid); + if (ret < 0) { + ERR("Unable to set group on %s", ustconsumer_data.err_unix_sock_path); + perror("chown"); + } + + DBG("All permissions are set"); + + end: + return ret; + } + + /* + * Create the pipe used to wake up the kernel thread. + */ + static int create_kernel_poll_pipe(void) + { + return pipe2(kernel_poll_pipe, O_CLOEXEC); + } + + /* + * Create the application command pipe to wake thread_manage_apps. + */ + static int create_apps_cmd_pipe(void) + { + return pipe2(apps_cmd_pipe, O_CLOEXEC); + } + + /* + * Create the lttng run directory needed for all global sockets and pipe. + */ + static int create_lttng_rundir(void) + { + int ret; + + ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG ); + if (ret < 0) { + if (errno != EEXIST) { + ERR("Unable to create " LTTNG_RUNDIR); + goto error; + } else { + ret = 0; + } + } + + error: + return ret; + } + + /* + * Setup sockets and directory needed by the kconsumerd communication with the + * session daemon. + */ + static int set_consumer_sockets(struct consumer_data *consumer_data) + { + int ret; + const char *path = consumer_data->type == LTTNG_CONSUMER_KERNEL ? + KCONSUMERD_PATH : USTCONSUMERD_PATH; + + if (strlen(consumer_data->err_unix_sock_path) == 0) { + snprintf(consumer_data->err_unix_sock_path, PATH_MAX, + consumer_data->type == LTTNG_CONSUMER_KERNEL ? + KCONSUMERD_ERR_SOCK_PATH : + USTCONSUMERD_ERR_SOCK_PATH); + } + + if (strlen(consumer_data->cmd_unix_sock_path) == 0) { + snprintf(consumer_data->cmd_unix_sock_path, PATH_MAX, + consumer_data->type == LTTNG_CONSUMER_KERNEL ? + KCONSUMERD_CMD_SOCK_PATH : + USTCONSUMERD_CMD_SOCK_PATH); + } + + ret = mkdir(path, S_IRWXU | S_IRWXG); + if (ret < 0) { + if (errno != EEXIST) { + ERR("Failed to create %s", path); + goto error; + } + ret = 0; + } + + /* Create the kconsumerd error unix socket */ + consumer_data->err_sock = + lttcomm_create_unix_sock(consumer_data->err_unix_sock_path); + if (consumer_data->err_sock < 0) { + ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path); + ret = -1; + goto error; + } + + /* File permission MUST be 660 */ + ret = chmod(consumer_data->err_unix_sock_path, + S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); + if (ret < 0) { + ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path); + perror("chmod"); + goto error; + } + + error: + return ret; + } + + /* + * Signal handler for the daemon + * + * Simply stop all worker threads, leaving main() return gracefully after + * joining all threads and calling cleanup(). + */ + static void sighandler(int sig) + { + switch (sig) { + case SIGPIPE: + DBG("SIGPIPE catched"); + return; + case SIGINT: + DBG("SIGINT catched"); + stop_threads(); + break; + case SIGTERM: + DBG("SIGTERM catched"); + stop_threads(); + break; + default: + break; + } + } + + /* + * Setup signal handler for : + * SIGINT, SIGTERM, SIGPIPE + */ + static int set_signal_handler(void) + { + int ret = 0; + struct sigaction sa; + sigset_t sigset; + + if ((ret = sigemptyset(&sigset)) < 0) { + perror("sigemptyset"); + return ret; + } + + sa.sa_handler = sighandler; + sa.sa_mask = sigset; + sa.sa_flags = 0; + if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { + perror("sigaction"); + return ret; + } + + if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) { + perror("sigaction"); + return ret; + } + + if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) { + perror("sigaction"); + return ret; + } + + DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT"); + + return ret; + } + + /* + * Set open files limit to unlimited. This daemon can open a large number of + * file descriptors in order to consumer multiple kernel traces. + */ + static void set_ulimit(void) + { + int ret; + struct rlimit lim; + + /* The kernel does not allowed an infinite limit for open files */ + lim.rlim_cur = 65535; + lim.rlim_max = 65535; + + ret = setrlimit(RLIMIT_NOFILE, &lim); + if (ret < 0) { + perror("failed to set open files limit"); + } + } + + /* + * main + */ + int main(int argc, char **argv) + { + int ret = 0; + void *status; + const char *home_path; + ++ tracepoint(sessiond_boot_start); + rcu_register_thread(); + + /* Create thread quit pipe */ + if ((ret = init_thread_quit_pipe()) < 0) { + goto error; + } + + /* Parse arguments */ + progname = argv[0]; + if ((ret = parse_args(argc, argv) < 0)) { + goto error; + } + + /* Daemonize */ + if (opt_daemon) { + ret = daemon(0, 0); + if (ret < 0) { + perror("daemon"); + goto error; + } + } + + /* Check if daemon is UID = 0 */ + is_root = !getuid(); + + if (is_root) { + ret = create_lttng_rundir(); + if (ret < 0) { + goto error; + } + + if (strlen(apps_unix_sock_path) == 0) { + snprintf(apps_unix_sock_path, PATH_MAX, + DEFAULT_GLOBAL_APPS_UNIX_SOCK); + } + + if (strlen(client_unix_sock_path) == 0) { + 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) { + /* TODO: Add --socket PATH option */ + ERR("Can't get HOME directory for sockets creation."); + ret = -EPERM; + goto error; + } + + if (strlen(apps_unix_sock_path) == 0) { + snprintf(apps_unix_sock_path, PATH_MAX, + DEFAULT_HOME_APPS_UNIX_SOCK, home_path); + } + + /* Set the cli tool unix socket path */ + if (strlen(client_unix_sock_path) == 0) { + 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); + DBG("Application socket path %s", apps_unix_sock_path); + + /* + * See if daemon already exist. + */ + if ((ret = check_existing_daemon()) < 0) { + ERR("Already running daemon.\n"); + /* + * We do not goto exit because we must not cleanup() + * because a daemon is already running. + */ + goto error; + } + + /* After this point, we can safely call cleanup() with "goto exit" */ + + /* + * These actions must be executed as root. We do that *after* setting up + * the sockets path because we MUST make the check for another daemon using + * those paths *before* trying to set the kernel consumer sockets and init + * kernel tracer. + */ + if (is_root) { + ret = set_consumer_sockets(&kconsumer_data); + if (ret < 0) { + goto exit; + } + + ret = set_consumer_sockets(&ustconsumer_data); + if (ret < 0) { + goto exit; + } + /* Setup kernel tracer */ + init_kernel_tracer(); + + /* Set ulimit for open files */ + set_ulimit(); + } + + if ((ret = set_signal_handler()) < 0) { + goto exit; + } + + /* Setup the needed unix socket */ + if ((ret = init_daemon_socket()) < 0) { + goto exit; + } + + /* Set credentials to socket */ + if (is_root && ((ret = set_permissions()) < 0)) { + goto exit; + } + + /* Get parent pid if -S, --sig-parent is specified. */ + if (opt_sig_parent) { + ppid = getppid(); + } + + /* Setup the kernel pipe for waking up the kernel thread */ + if ((ret = create_kernel_poll_pipe()) < 0) { + goto exit; + } + + /* Setup the thread apps communication pipe. */ + if ((ret = create_apps_cmd_pipe()) < 0) { + goto exit; + } + + /* Init UST command queue. */ + cds_wfq_init(&ust_cmd_queue.queue); + + /* Init UST app hash table */ + ust_app_ht_alloc(); + + /* + * Get session list pointer. This pointer MUST NOT be free(). This list is + * statically declared in session.c + */ + session_list_ptr = session_get_list(); + + /* Set up max poll set size */ + lttng_poll_set_max_size(); + + /* Create thread to manage the client socket */ + ret = pthread_create(&client_thread, NULL, + thread_manage_clients, (void *) NULL); + if (ret != 0) { + perror("pthread_create clients"); + goto exit_client; + } + + /* Create thread to dispatch registration */ + ret = pthread_create(&dispatch_thread, NULL, + thread_dispatch_ust_registration, (void *) NULL); + if (ret != 0) { + perror("pthread_create dispatch"); + goto exit_dispatch; + } + + /* Create thread to manage application registration. */ + ret = pthread_create(®_apps_thread, NULL, + thread_registration_apps, (void *) NULL); + if (ret != 0) { + perror("pthread_create registration"); + goto exit_reg_apps; + } + + /* Create thread to manage application socket */ + ret = pthread_create(&apps_thread, NULL, + thread_manage_apps, (void *) NULL); + if (ret != 0) { + perror("pthread_create apps"); + goto exit_apps; + } + + /* Create kernel thread to manage kernel event */ + ret = pthread_create(&kernel_thread, NULL, + thread_manage_kernel, (void *) NULL); + if (ret != 0) { + perror("pthread_create kernel"); + goto exit_kernel; + } + ++ tracepoint(sessiond_boot_end); ++ + ret = pthread_join(kernel_thread, &status); + if (ret != 0) { + perror("pthread_join"); + goto error; /* join error, exit without cleanup */ + } + + exit_kernel: + ret = pthread_join(apps_thread, &status); + if (ret != 0) { + perror("pthread_join"); + goto error; /* join error, exit without cleanup */ + } + + exit_apps: + ret = pthread_join(reg_apps_thread, &status); + if (ret != 0) { + perror("pthread_join"); + goto error; /* join error, exit without cleanup */ + } + + exit_reg_apps: + ret = pthread_join(dispatch_thread, &status); + if (ret != 0) { + perror("pthread_join"); + goto error; /* join error, exit without cleanup */ + } + + exit_dispatch: + ret = pthread_join(client_thread, &status); + if (ret != 0) { + perror("pthread_join"); + goto error; /* join error, exit without cleanup */ + } + + ret = join_consumer_thread(&kconsumer_data); + if (ret != 0) { + perror("join_consumer"); + goto error; /* join error, exit without cleanup */ + } + + exit_client: + exit: + /* + * cleanup() is called when no other thread is running. + */ + rcu_thread_online(); + cleanup(); + rcu_thread_offline(); + rcu_unregister_thread(); + if (!ret) + exit(EXIT_SUCCESS); + error: + exit(EXIT_FAILURE); + } diff --cc lttng-sessiond/shm.c index 000000000,7dac1659f..1ccaec5d8 mode 000000,100644..100644 --- a/lttng-sessiond/shm.c +++ b/lttng-sessiond/shm.c @@@ -1,0 -1,160 +1,172 @@@ + /* + * Copyright (C) 2011 - David Goulet + * Mathieu Desnoyers + * + * 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; only version 2 of the License. + * + * 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. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 59 Temple + * Place - Suite 330, Boston, MA 02111-1307, USA. + */ + + #define _GNU_SOURCE + #include + #include + #include + #include + #include + #include + #include + #include + + #include + ++#include "benchmark.h" ++#include "measures.h" + #include "shm.h" + + /* + * Using fork to set umask in the child process (not multi-thread safe). We + * deal with the shm_open vs ftruncate race (happening when the sessiond owns + * the shm and does not let everybody modify it, to ensure safety against + * shm_unlink) by simply letting the mmap fail and retrying after a few + * seconds. For global shm, everybody has rw access to it until the sessiond + * starts. + */ + static int get_wait_shm(char *shm_path, size_t mmap_size, int global) + { + int wait_shm_fd, ret; + mode_t mode; + ++ tracepoint(ust_notify_perms_start); ++ + /* Default permissions */ + mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP; + + /* Change owner of the shm path */ + if (global) { + ret = chown(shm_path, 0, 0); + if (ret < 0) { + if (errno != ENOENT) { + perror("chown wait shm"); + goto error; + } + } + + /* + * If global session daemon, any application can register so the shm + * needs to be set in read-only mode for others. + */ + mode |= S_IROTH; + } else { + ret = chown(shm_path, getuid(), getgid()); + if (ret < 0) { + if (errno != ENOENT) { + perror("chown wait shm"); + goto error; + } + } + } + + /* + * Set permissions to the shm even if we did not create the shm. + */ + ret = chmod(shm_path, mode); + if (ret < 0) { + if (errno != ENOENT) { + perror("chmod wait shm"); + goto error; + } + } + + /* + * We're alone in a child process, so we can modify the process-wide + * umask. + */ + umask(~mode); + ++ tracepoint(ust_notify_perms_stop); ++ ++ tracepoint(ust_notify_shm_start); + /* + * Try creating shm (or get rw access). We don't do an exclusive open, + * because we allow other processes to create+ftruncate it concurrently. + */ + wait_shm_fd = shm_open(shm_path, O_RDWR | O_CREAT, mode); + if (wait_shm_fd < 0) { + perror("shm_open wait shm"); + goto error; + } + + ret = ftruncate(wait_shm_fd, mmap_size); + if (ret < 0) { + perror("ftruncate wait shm"); + exit(EXIT_FAILURE); + } + + ret = fchmod(wait_shm_fd, mode); + if (ret < 0) { + perror("fchmod"); + exit(EXIT_FAILURE); + } + ++ tracepoint(ust_notify_shm_stop); ++ + DBG("Got the wait shm fd %d", wait_shm_fd); + + return wait_shm_fd; + + error: + DBG("Failing to get the wait shm fd"); + + return -1; + } + + /* + * Return the wait shm mmap for UST application notification. The global + * variable is used to indicate if the the session daemon is global + * (root:tracing) or running with an unprivileged user. + * + * This returned value is used by futex_wait_update() in futex.c to WAKE all + * waiters which are UST application waiting for a session daemon. + */ + char *shm_ust_get_mmap(char *shm_path, int global) + { + size_t mmap_size = sysconf(_SC_PAGE_SIZE); + int wait_shm_fd, ret; + char *wait_shm_mmap; + + wait_shm_fd = get_wait_shm(shm_path, mmap_size, global); + if (wait_shm_fd < 0) { + goto error; + } + ++ tracepoint(ust_notify_mmap_start); ++ + wait_shm_mmap = mmap(NULL, mmap_size, PROT_WRITE | PROT_READ, + MAP_SHARED, wait_shm_fd, 0); + ++ tracepoint(ust_notify_mmap_stop); + /* close shm fd immediately after taking the mmap reference */ + ret = close(wait_shm_fd); + if (ret) { + perror("Error closing fd"); + } + + if (wait_shm_mmap == MAP_FAILED) { + DBG("mmap error (can be caused by race with ust)."); + goto error; + } + + return wait_shm_mmap; + + error: + return NULL; + }