+/* Copyright (C) 2009 Pierre-Marc Fournier
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
#define _GNU_SOURCE
#include <stdio.h>
#include <stdint.h>
#include <sched.h>
#include <fcntl.h>
#include <poll.h>
+#include <regex.h>
+
+#include <urcu.h>
#include "marker.h"
#include "tracer.h"
#include "localerr.h"
#include "ustcomm.h"
#include "relay.h" /* FIXME: remove */
+#include "marker-control.h"
//#define USE_CLONE
uint16_t command;
};
+/* volatile because shared between the listener and the main thread */
+volatile sig_atomic_t buffers_to_export = 0;
+
//struct listener_arg {
// int pipe_fd;
//};
unlock_markers();
}
-void do_command(struct tracecmd *cmd)
-{
-}
+static int init_socket(void);
+
+/* This needs to be called whenever a new thread is created. It notifies
+ * liburcu of the new thread.
+ */
-void receive_commands()
+void ust_register_thread(void)
{
+ rcu_register_thread();
}
int fd_notif = -1;
}
}
-static void inform_consumer_daemon(void)
+/* Ask the daemon to collect a trace called trace_name and being
+ * produced by this pid.
+ *
+ * The trace must be at least allocated. (It can also be started.)
+ * This is because _ltt_trace_find is used.
+ */
+
+static void inform_consumer_daemon(const char *trace_name)
{
- ustcomm_request_consumer(getpid(), "metadata");
- ustcomm_request_consumer(getpid(), "ust");
+ int i;
+ struct ltt_trace_struct *trace;
+ pid_t pid = getpid();
+ int result;
+
+ ltt_lock_traces();
+
+ trace = _ltt_trace_find(trace_name);
+ if(trace == NULL) {
+ WARN("inform_consumer_daemon: could not find trace \"%s\"; it is probably already destroyed", trace_name);
+ goto finish;
+ }
+
+ for(i=0; i < trace->nr_channels; i++) {
+ result = ustcomm_request_consumer(pid, trace->channels[i].channel_name);
+ if(result == -1) {
+ WARN("Failed to request collection for channel %s. Is the daemon available?", trace->channels[i].channel_name);
+ /* continue even if fail */
+ }
+ buffers_to_export++;
+ }
+
+ finish:
+ ltt_unlock_traces();
}
void process_blocked_consumers(void)
idx++;
}
- result = poll(fds, n_fds, 0);
+ while((result = poll(fds, n_fds, 0)) == -1 && errno == EINTR)
+ /* nothing */;
if(result == -1) {
PERROR("poll");
return;
{
int result;
+ ust_register_thread();
+
DBG("LISTENER");
for(;;) {
- uint32_t size;
- struct sockaddr_un addr;
- socklen_t addrlen = sizeof(addr);
char trace_name[] = "auto";
char trace_type[] = "ustrelay";
char *recvbuf;
continue;
}
- DBG("received a message! it's: %s\n", recvbuf);
+ DBG("received a message! it's: %s", recvbuf);
len = strlen(recvbuf);
if(!strcmp(recvbuf, "print_markers")) {
return (void *)1;
}
- inform_consumer_daemon();
+ inform_consumer_daemon(trace_name);
result = ltt_trace_start(trace_name);
if(result < 0) {
struct rchan *rchan = trace->channels[i].trans_channel_data;
struct rchan_buf *rbuf = rchan->buf;
struct ltt_channel_struct *ltt_channel = (struct ltt_channel_struct *)rchan->private_data;
- struct ltt_channel_buf_struct *ltt_buf = ltt_channel->buf;
if(!strcmp(trace->channels[i].channel_name, channel_name)) {
char *reply;
break;
}
}
+
+ buffers_to_export--;
}
else if(nth_token_is(recvbuf, "get_n_subbufs", 0) == 1) {
struct ltt_trace_struct *trace;
if(!strcmp(trace->channels[i].channel_name, channel_name)) {
struct rchan_buf *rbuf = rchan->buf;
struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
- char *reply;
- long consumed_old=0;
- int fd;
struct blocked_consumer *bc;
bc = (struct blocked_consumer *) malloc(sizeof(struct blocked_consumer));
char *channel_slash_name = nth_token(recvbuf, 1);
char channel_name[256]="";
char marker_name[256]="";
- struct marker_iter iter;
result = sscanf(channel_slash_name, "%255[^/]/%255s", channel_name, marker_name);
char *channel_slash_name = nth_token(recvbuf, 1);
char *marker_name;
char *channel_name;
- struct marker_iter iter;
result = sscanf(channel_slash_name, "%a[^/]/%as", &channel_name, &marker_name);
}
}
-static char listener_stack[16384];
+int have_listener = 0;
void create_listener(void)
{
- int result;
+#ifdef USE_CLONE
static char listener_stack[16384];
- //char *listener_stack = malloc(16384);
+#else
+ pthread_t thread;
+#endif
+
+ if(have_listener)
+ return;
#ifdef USE_CLONE
result = clone(listener_main, listener_stack+sizeof(listener_stack)-1, CLONE_FS | CLONE_FILES | CLONE_VM | CLONE_SIGHAND | CLONE_THREAD, NULL);
if(result == -1) {
perror("clone");
+ return;
}
#else
- pthread_t thread;
pthread_create(&thread, NULL, listener_main, NULL);
#endif
+
+ have_listener = 1;
}
/* The signal handler itself. Signals must be setup so there cannot be
return ustcomm_init_app(getpid(), &ustcomm_app);
}
-static void destroy_socket(void)
-{
-// int result;
-//
-// if(mysocketfile[0] == '\0')
-// return;
-//
-// result = unlink(mysocketfile);
-// if(result == -1) {
-// PERROR("unlink");
-// }
-}
-
static int init_signal_handler(void)
{
/* Attempt to handler SIGIO. If the main program wants to
return 0;
}
+#define AUTOPROBE_DISABLED 0
+#define AUTOPROBE_ENABLE_ALL 1
+#define AUTOPROBE_ENABLE_REGEX 2
+static int autoprobe_method = AUTOPROBE_DISABLED;
+static regex_t autoprobe_regex;
+
static void auto_probe_connect(struct marker *m)
{
int result;
- result = ltt_marker_connect(m->channel, m->name, "default");
- if(result)
- ERR("ltt_marker_connect");
+ char* concat_name = NULL;
+ const char *probe_name = "default";
- DBG("just auto connected marker %s %s to probe default", m->channel, m->name);
-}
-
-static void __attribute__((constructor(101))) init0()
-{
- DBG("UST_AUTOPROBE constructor");
- if(getenv("UST_AUTOPROBE")) {
- marker_set_new_marker_cb(auto_probe_connect);
+ if(autoprobe_method == AUTOPROBE_DISABLED) {
+ return;
+ }
+ else if(autoprobe_method == AUTOPROBE_ENABLE_REGEX) {
+ result = asprintf(&concat_name, "%s/%s", m->channel, m->name);
+ if(result == -1) {
+ ERR("auto_probe_connect: asprintf failed (marker %s/%s)",
+ m->channel, m->name);
+ return;
+ }
+ if (regexec(&autoprobe_regex, concat_name, 0, NULL, 0)) {
+ free(concat_name);
+ return;
+ }
+ free(concat_name);
}
-}
-static void fini(void);
+ result = ltt_marker_connect(m->channel, m->name, probe_name);
+ if(result && result != -EEXIST)
+ ERR("ltt_marker_connect (marker = %s/%s, errno = %d)", m->channel, m->name, -result);
+
+ DBG("auto connected marker %s %s to probe default", m->channel, m->name);
+
+}
static void __attribute__((constructor(1000))) init()
{
int result;
+ char* autoprobe_val = NULL;
- DBG("UST_TRACE constructor");
+ /* Initialize RCU in case the constructor order is not good. */
+ urcu_init();
+
+ /* It is important to do this before events start to be generated. */
+ ust_register_thread();
+
+ DBG("Tracectl constructor");
/* Must create socket before signal handler to prevent races.
*/
return;
}
+ autoprobe_val = getenv("UST_AUTOPROBE");
+ if(autoprobe_val) {
+ struct marker_iter iter;
+
+ DBG("Autoprobe enabled.");
+
+ /* Ensure markers are initialized */
+ //init_markers();
+
+ /* Ensure marker control is initialized, for the probe */
+ init_marker_control();
+
+ /* first, set the callback that will connect the
+ * probe on new markers
+ */
+ if(autoprobe_val[0] == '/') {
+ result = regcomp(&autoprobe_regex, autoprobe_val+1, 0);
+ if (result) {
+ char regexerr[150];
+
+ regerror(result, &autoprobe_regex, regexerr, sizeof(regexerr));
+ ERR("cannot parse regex %s (%s), will ignore UST_AUTOPROBE", autoprobe_val, regexerr);
+ /* don't crash the application just for this */
+ }
+ else {
+ autoprobe_method = AUTOPROBE_ENABLE_REGEX;
+ }
+ }
+ else {
+ /* just enable all instrumentation */
+ autoprobe_method = AUTOPROBE_ENABLE_ALL;
+ }
+
+ marker_set_new_marker_cb(auto_probe_connect);
+
+ /* Now, connect the probes that were already registered. */
+ marker_iter_reset(&iter);
+ marker_iter_start(&iter);
+
+ DBG("now iterating on markers already registered");
+ while(iter.marker) {
+ DBG("now iterating on marker %s", iter.marker->name);
+ auto_probe_connect(iter.marker);
+ marker_iter_next(&iter);
+ }
+ }
+
if(getenv("UST_TRACE")) {
char trace_name[] = "auto";
char trace_type[] = "ustrelay";
return;
}
+ inform_consumer_daemon(trace_name);
+
result = ltt_trace_start(trace_name);
if(result < 0) {
ERR("ltt_trace_start failed");
return;
}
- inform_consumer_daemon();
}
}
/* This is only called if we terminate normally, not with an unhandled signal,
- * so we cannot rely on it. */
-
-/* This destructor probably isn't needed, because ustd can do crash recovery. */
-#if 0
-static void __attribute__((destructor)) fini()
+ * so we cannot rely on it. However, for now, LTTV requires that the header of
+ * the last sub-buffer contain a valid end time for the trace. This is done
+ * automatically only when the trace is properly stopped.
+ *
+ * If the traced program crashed, it is always possible to manually add the
+ * right value in the header, or to open the trace in text mode.
+ *
+ * FIXME: Fix LTTV so it doesn't need this.
+ */
+
+static void destroy_traces(void)
{
int result;
if(result == -1) {
ERR("ltt_trace_destroy error");
}
+}
+
+static int trace_recording(void)
+{
+ int retval = 0;
+ struct ltt_trace_struct *trace;
+
+ ltt_lock_traces();
+
+ list_for_each_entry(trace, <t_traces.head, list) {
+ if(trace->active) {
+ retval = 1;
+ break;
+ }
+ }
+
+ ltt_unlock_traces();
- destroy_socket();
+ return retval;
+}
+
+#if 0
+static int have_consumer(void)
+{
+ return !list_empty(&blocked_consumers);
}
#endif
+
+int restarting_usleep(useconds_t usecs)
+{
+ struct timespec tv;
+ int result;
+
+ tv.tv_sec = 0;
+ tv.tv_nsec = usecs * 1000;
+
+ do {
+ result = nanosleep(&tv, &tv);
+ } while(result == -1 && errno == EINTR);
+
+ return result;
+}
+
+/* This destructor keeps the process alive for a few seconds in order
+ * to leave time to ustd to connect to its buffers. This is necessary
+ * for programs whose execution is very short. It is also useful in all
+ * programs when tracing is started close to the end of the program
+ * execution.
+ *
+ * FIXME: For now, this only works for the first trace created in a
+ * process.
+ */
+
+static void __attribute__((destructor)) keepalive()
+{
+ if(trace_recording() && buffers_to_export) {
+ int total = 0;
+ DBG("Keeping process alive for consumer daemon...");
+ while(buffers_to_export) {
+ const int interv = 200000;
+ restarting_usleep(interv);
+ total += interv;
+
+ if(total >= 3000000) {
+ WARN("non-consumed buffers remaining after wait limit; not waiting anymore");
+ break;
+ }
+ }
+ DBG("Finally dying...");
+ }
+
+ destroy_traces();
+
+ ustcomm_fini_app(&ustcomm_app);
+}
+
+/* Notify ust that there was a fork. This needs to be called inside
+ * the new process, anytime a process whose memory is not shared with
+ * the parent is created. If this function is not called, the events
+ * of the new process will not be collected.
+ */
+
+void ust_fork(void)
+{
+ struct blocked_consumer *bc;
+ struct blocked_consumer *deletable_bc = NULL;
+ int result;
+
+ DBG("ust: forking");
+ ltt_trace_stop("auto");
+ ltt_trace_destroy("auto");
+ /* Delete all active connections */
+ ustcomm_close_all_connections(&ustcomm_app.server);
+
+ /* Delete all blocked consumers */
+ list_for_each_entry(bc, &blocked_consumers, list) {
+ free(deletable_bc);
+ deletable_bc = bc;
+ list_del(&bc->list);
+ }
+
+ have_listener = 0;
+ create_listener();
+ init_socket();
+ ltt_trace_setup("auto");
+ result = ltt_trace_set_type("auto", "ustrelay");
+ if(result < 0) {
+ ERR("ltt_trace_set_type failed");
+ return;
+ }
+
+ ltt_trace_alloc("auto");
+ ltt_trace_start("auto");
+ inform_consumer_daemon("auto");
+}
+