* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+/* This file contains the implementation of the UST listener thread, which
+ * receives trace control commands. It also coordinates the initialization of
+ * libust.
+ */
+
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
+#include <pthread.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/socket.h>
#define MSG_NOTIF 1
#define MSG_REGISTER_NOTIF 2
-char consumer_stack[10000];
-
/* This should only be accessed by the constructor, before the creation
* of the listener, and then only by the listener.
*/
s64 pidunique = -1LL;
+extern struct chan_info_struct chan_infos[];
+
struct list_head blocked_consumers = LIST_HEAD_INIT(blocked_consumers);
static struct ustcomm_app ustcomm_app;
};
/* volatile because shared between the listener and the main thread */
-volatile sig_atomic_t buffers_to_export = 0;
+int buffers_to_export = 0;
struct trctl_msg {
/* size: the size of all the fields except size itself */
}
for(i=0; i < trace->nr_channels; i++) {
- /* iterate on all cpus */
- for(j=0; j<trace->channels[i].n_cpus; j++) {
- char *buf;
- asprintf(&buf, "%s_%d", trace->channels[i].channel_name, j);
- result = ustcomm_request_consumer(pid, buf);
- if(result == -1) {
- WARN("Failed to request collection for channel %s. Is the daemon available?", trace->channels[i].channel_name);
- /* continue even if fail */
+ if(trace->channels[i].request_collection) {
+ /* iterate on all cpus */
+ for(j=0; j<trace->channels[i].n_cpus; j++) {
+ char *buf;
+ if (asprintf(&buf, "%s_%d", trace->channels[i].channel_name, j) < 0) {
+ ERR("inform_consumer_daemon : asprintf failed (%s_%d)",
+ trace->channels[i].channel_name, j);
+ goto finish;
+ }
+ result = ustcomm_request_consumer(pid, buf);
+ if(result == -1) {
+ WARN("Failed to request collection for channel %s. Is the daemon available?", trace->channels[i].channel_name);
+ /* continue even if fail */
+ }
+ free(buf);
+ STORE_SHARED(buffers_to_export, LOAD_SHARED(buffers_to_export)+1);
}
- free(buf);
- buffers_to_export++;
}
}
else if(result < 0) {
ERR("ust_buffers_get_subbuf: error: %s", strerror(-result));
}
- asprintf(&reply, "%s %ld", "OK", consumed_old);
+ if (asprintf(&reply, "%s %ld", "OK", consumed_old) < 0) {
+ ERR("process_blkd_consumer_act : asprintf failed (OK %ld)",
+ consumed_old);
+ return -1;
+ }
result = ustcomm_send_reply(&bc->server, reply, &bc->src);
if(result < 0) {
ERR("ustcomm_send_reply failed");
*cpu = atoi(sep+1);
}
- asprintf(channel, "%.*s", (int)(sep-channel_and_cpu), channel_and_cpu);
+ if (asprintf(channel, "%.*s", (int)(sep-channel_and_cpu), channel_and_cpu) < 0) {
+ ERR("seperate_channel_cpu : asprintf failed (%.*s)",
+ (int)(sep-channel_and_cpu), channel_and_cpu);
+ return;
+ }
}
static int do_cmd_get_shmid(const char *recvbuf, struct ustcomm_source *src)
channel_and_cpu = nth_token(recvbuf, 1);
if(channel_and_cpu == NULL) {
ERR("cannot parse channel");
+ retval = -1;
goto end;
}
seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
if(ch_cpu == -1) {
ERR("problem parsing channel name");
+ retval = -1;
goto free_short_chan_name;
}
// DBG("the shmid for the requested channel is %d", buf->shmid);
// DBG("the shmid for its buffer structure is %d", channel->buf_struct_shmids);
- asprintf(&reply, "%d %d", buf->shmid, channel->buf_struct_shmids[ch_cpu]);
+ if (asprintf(&reply, "%d %d", buf->shmid, channel->buf_struct_shmids[ch_cpu]) < 0) {
+ ERR("do_cmd_get_shmid : asprintf failed (%d %d)",
+ buf->shmid, channel->buf_struct_shmids[ch_cpu]);
+ retval = -1;
+ goto free_short_chan_name;
+ }
result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
if(result) {
channel_and_cpu = nth_token(recvbuf, 1);
if(channel_and_cpu == NULL) {
ERR("cannot parse channel");
+ retval = -1;
goto end;
}
seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
if(ch_cpu == -1) {
ERR("problem parsing channel name");
+ retval = -1;
goto free_short_chan_name;
}
char *reply;
DBG("the n_subbufs for the requested channel is %d", channel->subbuf_cnt);
- asprintf(&reply, "%d", channel->subbuf_cnt);
+ if (asprintf(&reply, "%d", channel->subbuf_cnt) < 0) {
+ ERR("do_cmd_get_n_subbufs : asprintf failed (%d)",
+ channel->subbuf_cnt);
+ retval = -1;
+ goto free_short_chan_name;
+ }
result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
if(result) {
channel_and_cpu = nth_token(recvbuf, 1);
if(channel_and_cpu == NULL) {
ERR("cannot parse channel");
+ retval = -1;
goto end;
}
seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
if(ch_cpu == -1) {
ERR("problem parsing channel name");
+ retval = -1;
goto free_short_chan_name;
}
char *reply;
DBG("the subbuf_size for the requested channel is %zd", channel->subbuf_size);
- asprintf(&reply, "%zd", channel->subbuf_size);
+ if (asprintf(&reply, "%zd", channel->subbuf_size) < 0) {
+ ERR("do_cmd_get_subbuf_size : asprintf failed (%zd)",
+ channel->subbuf_size);
+ retval = -1;
+ goto free_short_chan_name;
+ }
result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
if(result) {
return retval;
}
-static unsigned int poweroftwo(unsigned int x)
-{
- unsigned int power2 = 1;
- unsigned int hardcoded = 2147483648; /* FIX max 2^31 */
-
- if (x < 2)
- return 2;
+/* Return the power of two which is equal or higher to v */
- while (power2 < x && power2 < hardcoded)
- power2 *= 2;
+static unsigned int pow2_higher_or_eq(unsigned int v)
+{
+ int hb = fls(v);
+ int retval = 1<<(hb-1);
- return power2;
+ if(v-retval == 0)
+ return retval;
+ else
+ return retval<<1;
}
static int do_cmd_set_subbuf_size(const char *recvbuf, struct ustcomm_source *src)
if(ch_name == NULL) {
ERR("cannot parse channel");
+ retval = -1;
goto end;
}
- power = poweroftwo(size);
+ power = pow2_higher_or_eq(size);
+ power = max_t(unsigned int, 2u, power);
if (power != size)
- WARN("using the next 2^n = %u\n", power);
+ WARN("using the next power of two for buffer size = %u\n", power);
ltt_lock_traces();
trace = _ltt_trace_find_setup(trace_name);
if(ch_name == NULL) {
ERR("cannot parse channel");
+ retval = -1;
goto end;
}
if (num < 2) {
ERR("subbuffer count should be greater than 2");
+ retval = -1;
goto end;
}
channel_and_cpu = nth_token(recvbuf, 1);
if(channel_and_cpu == NULL) {
ERR("cannot parse channel");
+ retval = -1;
goto end;
}
seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
if(ch_cpu == -1) {
ERR("problem parsing channel name");
+ retval = -1;
goto free_short_chan_name;
}
found = 1;
- bc = (struct blocked_consumer *) malloc(sizeof(struct blocked_consumer));
+ bc = (struct blocked_consumer *) zmalloc(sizeof(struct blocked_consumer));
if(bc == NULL) {
- ERR("malloc returned NULL");
+ ERR("zmalloc returned NULL");
goto unlock_traces;
}
bc->fd_consumer = src->fd;
*/
if(uatomic_read(&buf->consumed) == 0) {
DBG("decrementing buffers_to_export");
- buffers_to_export--;
+ STORE_SHARED(buffers_to_export, LOAD_SHARED(buffers_to_export)-1);
}
break;
result = ust_buffers_put_subbuf(buf, consumed_old);
if(result < 0) {
WARN("ust_buffers_put_subbuf: error (subbuf=%s)", channel_and_cpu);
- asprintf(&reply, "%s", "ERROR");
+ if (asprintf(&reply, "%s", "ERROR") < 0) {
+ ERR("do_cmd_put_subbuffer : asprintf failed (ERROR)");
+ retval = -1;
+ goto unlock_traces;
+ }
}
else {
DBG("ust_buffers_put_subbuf: success (subbuf=%s)", channel_and_cpu);
- asprintf(&reply, "%s", "OK");
+ if (asprintf(&reply, "%s", "OK") < 0) {
+ ERR("do_cmd_put_subbuffer : asprintf failed (OK)");
+ retval = -1;
+ goto unlock_traces;
+ }
}
result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
ustcomm_fini_app(&ustcomm_app, 0);
}
+static void do_cmd_force_switch()
+{
+ struct blocked_consumer *bc;
+
+ list_for_each_entry(bc, &blocked_consumers, list) {
+ ltt_force_switch(bc->buf, FORCE_FLUSH);
+ }
+}
+
int process_client_cmd(char *recvbuf, struct ustcomm_source *src)
{
int result;
else if(nth_token_is(recvbuf, "get_pidunique", 0) == 1) {
char *reply;
- asprintf(&reply, "%lld", pidunique);
+ if (asprintf(&reply, "%lld", pidunique) < 0) {
+ ERR("process_client_cmd : asprintf failed (%lld)",
+ pidunique);
+ goto next_cmd;
+ }
result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
if(result) {
free(reply);
}
+ else if(nth_token_is(recvbuf, "get_sock_path", 0) == 1) {
+ char *reply = getenv("UST_DAEMON_SOCKET");
+ if(!reply) {
+ if (asprintf(&reply, "%s/%s", SOCK_DIR, "ustd") < 0) {
+ ERR("process_client_cmd : asprintf failed (%s/ustd)",
+ SOCK_DIR);
+ goto next_cmd;
+ }
+ result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
+ free(reply);
+ }
+ else {
+ result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
+ }
+ if(result)
+ ERR("ustcomm_send_reply failed");
+ }
+ else if(nth_token_is(recvbuf, "set_sock_path", 0) == 1) {
+ char *sock_path = nth_token(recvbuf, 1);
+ result = setenv("UST_DAEMON_SOCKET", sock_path, 1);
+ if(result)
+ ERR("cannot set UST_DAEMON_SOCKET environment variable");
+ }
+ else if(nth_token_is(recvbuf, "force_switch", 0) == 1) {
+ do_cmd_force_switch();
+ }
else {
ERR("unable to parse message: %s", recvbuf);
}
void create_listener(void)
{
int result;
+ sigset_t sig_all_blocked;
+ sigset_t orig_parent_mask;
if(have_listener) {
WARN("not creating listener because we already had one");
return;
}
+ /* A new thread created by pthread_create inherits the signal mask
+ * from the parent. To avoid any signal being received by the
+ * listener thread, we block all signals temporarily in the parent,
+ * while we create the listener thread.
+ */
+
+ sigfillset(&sig_all_blocked);
+
+ result = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_parent_mask);
+ if(result) {
+ PERROR("pthread_sigmask: %s", strerror(result));
+ }
+
result = pthread_create(&listener_thread, NULL, listener_main, NULL);
if(result == -1) {
PERROR("pthread_create");
}
- have_listener = 1;
+ /* Restore original signal mask in parent */
+ result = pthread_sigmask(SIG_SETMASK, &orig_parent_mask, NULL);
+ if(result) {
+ PERROR("pthread_sigmask: %s", strerror(result));
+ }
+ else {
+ have_listener = 1;
+ }
}
static int init_socket(void)
{
int result;
char* autoprobe_val = NULL;
+ char* subbuffer_size_val = NULL;
+ char* subbuffer_count_val = NULL;
+ unsigned int subbuffer_size;
+ unsigned int subbuffer_count;
+ unsigned int power;
/* Assign the pidunique, to be able to differentiate the processes with same
* pid, (before and after an exec).
}
}
+ if(getenv("UST_OVERWRITE")) {
+ int val = atoi(getenv("UST_OVERWRITE"));
+ if(val == 0 || val == 1) {
+ STORE_SHARED(ust_channels_overwrite_by_default, val);
+ }
+ else {
+ WARN("invalid value for UST_OVERWRITE");
+ }
+ }
+
+ if(getenv("UST_AUTOCOLLECT")) {
+ int val = atoi(getenv("UST_AUTOCOLLECT"));
+ if(val == 0 || val == 1) {
+ STORE_SHARED(ust_channels_request_collection_by_default, val);
+ }
+ else {
+ WARN("invalid value for UST_AUTOCOLLECT");
+ }
+ }
+
+ subbuffer_size_val = getenv("UST_SUBBUF_SIZE");
+ if(subbuffer_size_val) {
+ sscanf(subbuffer_size_val, "%u", &subbuffer_size);
+ power = pow2_higher_or_eq(subbuffer_size);
+ if(power != subbuffer_size)
+ WARN("using the next power of two for buffer size = %u\n", power);
+ chan_infos[LTT_CHANNEL_UST].def_subbufsize = power;
+ }
+
+ subbuffer_count_val = getenv("UST_SUBBUF_NUM");
+ if(subbuffer_count_val) {
+ sscanf(subbuffer_count_val, "%u", &subbuffer_count);
+ if(subbuffer_count < 2)
+ subbuffer_count = 2;
+ chan_infos[LTT_CHANNEL_UST].def_subbufcount = subbuffer_count;
+ }
+
if(getenv("UST_TRACE")) {
char trace_name[] = "auto";
char trace_type[] = "ustrelay";
inform_consumer_daemon(trace_name);
}
-
return;
/* should decrementally destroy stuff if error */
return result;
}
-static void stop_listener()
+static void stop_listener(void)
{
int result;
+ if(!have_listener)
+ return;
+
result = pthread_cancel(listener_thread);
if(result != 0) {
ERR("pthread_cancel: %s", strerror(result));
static void __attribute__((destructor)) keepalive()
{
- if(trace_recording() && buffers_to_export) {
+ if(trace_recording() && LOAD_SHARED(buffers_to_export)) {
int total = 0;
DBG("Keeping process alive for consumer daemon...");
- while(buffers_to_export) {
+ while(LOAD_SHARED(buffers_to_export)) {
const int interv = 200000;
restarting_usleep(interv);
total += interv;
/* free app, keeping socket file */
ustcomm_fini_app(&ustcomm_app, 1);
- buffers_to_export = 0;
+ STORE_SHARED(buffers_to_export, 0);
have_listener = 0;
init_socket();
create_listener();