-/* 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
- */
-
-/* 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
-#define _LGPL_SOURCE
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <pthread.h>
-#include <signal.h>
-#include <sys/epoll.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <fcntl.h>
-#include <poll.h>
-#include <regex.h>
-#include <urcu/uatomic.h>
-#include <urcu/list.h>
-
-#include <ust/marker.h>
-#include <ust/tracepoint.h>
-#include <ust/tracepoint-internal.h>
-#include <ust/tracectl.h>
-#include <ust/clock.h>
-#include "tracer.h"
-#include "usterr_signal_safe.h"
-#include "ustcomm.h"
-#include "buffers.h"
-#include "marker-control.h"
-
-/* This should only be accessed by the constructor, before the creation
- * of the listener, and then only by the listener.
- */
-s64 pidunique = -1LL;
-
-/* The process pid is used to detect a non-traceable fork
- * and allow the non-traceable fork to be ignored
- * by destructor sequences in libust
- */
-static pid_t processpid = 0;
-
-static struct ustcomm_header _receive_header;
-static struct ustcomm_header *receive_header = &_receive_header;
-static char receive_buffer[USTCOMM_BUFFER_SIZE];
-static char send_buffer[USTCOMM_BUFFER_SIZE];
-
-static int epoll_fd;
-
-/*
- * Listener thread data vs fork() protection mechanism. Ensures that no listener
- * thread mutexes and data structures are being concurrently modified or held by
- * other threads when fork() is executed.
- */
-static pthread_mutex_t listener_thread_data_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-/* Mutex protecting listen_sock. Nests inside listener_thread_data_mutex. */
-static pthread_mutex_t listen_sock_mutex = PTHREAD_MUTEX_INITIALIZER;
-static struct ustcomm_sock *listen_sock;
-
-extern struct chan_info_struct chan_infos[];
-
-static struct cds_list_head ust_socks = CDS_LIST_HEAD_INIT(ust_socks);
-
-/* volatile because shared between the listener and the main thread */
-int buffers_to_export = 0;
-
-int ust_clock_source;
-
-static long long make_pidunique(void)
-{
- s64 retval;
- struct timeval tv;
-
- gettimeofday(&tv, NULL);
-
- retval = tv.tv_sec;
- retval <<= 32;
- retval |= tv.tv_usec;
-
- return retval;
-}
-
-static void print_ust_marker(FILE *fp)
-{
- struct ust_marker_iter iter;
-
- ust_marker_iter_reset(&iter);
- ust_marker_iter_start(&iter);
-
- while (iter.ust_marker) {
- fprintf(fp, "ust_marker: %s/%s %d \"%s\" %p\n",
- (*iter.ust_marker)->channel,
- (*iter.ust_marker)->name,
- (int)(*iter.ust_marker)->state,
- (*iter.ust_marker)->format,
- NULL); /*
- * location is null for now, will be added
- * to a different table.
- */
- ust_marker_iter_next(&iter);
- }
- ust_marker_iter_stop(&iter);
-}
-
-static void print_trace_events(FILE *fp)
-{
- struct trace_event_iter iter;
-
- trace_event_iter_reset(&iter);
- trace_event_iter_start(&iter);
-
- while (iter.trace_event) {
- fprintf(fp, "trace_event: %s\n", (*iter.trace_event)->name);
- trace_event_iter_next(&iter);
- }
- trace_event_iter_stop(&iter);
-}
-
-static int connect_ustconsumer(void)
-{
- int result, fd;
- char default_daemon_path[] = SOCK_DIR "/ustconsumer";
- char *explicit_daemon_path, *daemon_path;
-
- explicit_daemon_path = getenv("UST_DAEMON_SOCKET");
- if (explicit_daemon_path) {
- daemon_path = explicit_daemon_path;
- } else {
- daemon_path = default_daemon_path;
- }
-
- DBG("Connecting to daemon_path %s", daemon_path);
-
- result = ustcomm_connect_path(daemon_path, &fd);
- if (result < 0) {
- WARN("connect_ustconsumer failed, daemon_path: %s",
- daemon_path);
- return result;
- }
-
- return fd;
-}
-
-
-static void request_buffer_consumer(int sock,
- const char *trace,
- const char *channel,
- int cpu)
-{
- struct ustcomm_header send_header, recv_header;
- struct ustcomm_buffer_info buf_inf;
- int result = 0;
-
- result = ustcomm_pack_buffer_info(&send_header,
- &buf_inf,
- trace,
- channel,
- cpu);
-
- if (result < 0) {
- ERR("failed to pack buffer info message %s_%d",
- channel, cpu);
- return;
- }
-
- buf_inf.pid = getpid();
- send_header.command = CONSUME_BUFFER;
-
- result = ustcomm_req(sock, &send_header, (char *) &buf_inf,
- &recv_header, NULL);
- if (result <= 0) {
- PERROR("request for buffer consumer failed, is the daemon online?");
- }
-
- return;
-}
-
-/* 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)
-{
- int sock, i,j;
- struct ust_trace *trace;
- const char *ch_name;
-
- sock = connect_ustconsumer();
- if (sock < 0) {
- return;
- }
-
- DBG("Connected to ustconsumer");
-
- 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 unlock_traces;
- }
-
- for (i=0; i < trace->nr_channels; i++) {
- if (trace->channels[i].request_collection) {
- /* iterate on all cpus */
- for (j=0; j<trace->channels[i].n_cpus; j++) {
- ch_name = trace->channels[i].channel_name;
- request_buffer_consumer(sock, trace_name,
- ch_name, j);
- CMM_STORE_SHARED(buffers_to_export,
- CMM_LOAD_SHARED(buffers_to_export)+1);
- }
- }
- }
-
-unlock_traces:
- ltt_unlock_traces();
-
- close(sock);
-}
-
-static struct ust_channel *find_channel(const char *ch_name,
- struct ust_trace *trace)
-{
- int i;
-
- for (i=0; i<trace->nr_channels; i++) {
- if (!strcmp(trace->channels[i].channel_name, ch_name)) {
- return &trace->channels[i];
- }
- }
-
- return NULL;
-}
-
-static int get_buffer_shmid_pipe_fd(const char *trace_name, const char *ch_name,
- int ch_cpu,
- int *buf_shmid,
- int *buf_struct_shmid,
- int *buf_pipe_fd)
-{
- struct ust_trace *trace;
- struct ust_channel *channel;
- struct ust_buffer *buf;
-
- DBG("get_buffer_shmid_pipe_fd");
-
- ltt_lock_traces();
- trace = _ltt_trace_find(trace_name);
- ltt_unlock_traces();
-
- if (trace == NULL) {
- ERR("cannot find trace!");
- return -ENODATA;
- }
-
- channel = find_channel(ch_name, trace);
- if (!channel) {
- ERR("cannot find channel %s!", ch_name);
- return -ENODATA;
- }
-
- buf = channel->buf[ch_cpu];
-
- *buf_shmid = buf->shmid;
- *buf_struct_shmid = channel->buf_struct_shmids[ch_cpu];
- *buf_pipe_fd = buf->data_ready_fd_read;
-
- return 0;
-}
-
-static int get_subbuf_num_size(const char *trace_name, const char *ch_name,
- int *num, int *size)
-{
- struct ust_trace *trace;
- struct ust_channel *channel;
-
- DBG("get_subbuf_size");
-
- ltt_lock_traces();
- trace = _ltt_trace_find(trace_name);
- ltt_unlock_traces();
-
- if (!trace) {
- ERR("cannot find trace!");
- return -ENODATA;
- }
-
- channel = find_channel(ch_name, trace);
- if (!channel) {
- ERR("unable to find channel");
- return -ENODATA;
- }
-
- *num = channel->subbuf_cnt;
- *size = channel->subbuf_size;
-
- return 0;
-}
-
-/* Return the power of two which is equal or higher to v */
-
-static unsigned int pow2_higher_or_eq(unsigned int v)
-{
- int hb = fls(v);
- int retval = 1<<(hb-1);
-
- if (v-retval == 0)
- return retval;
- else
- return retval<<1;
-}
-
-static int set_subbuf_size(const char *trace_name, const char *ch_name,
- unsigned int size)
-{
- unsigned int power;
- int retval = 0;
- struct ust_trace *trace;
- struct ust_channel *channel;
-
- DBG("set_subbuf_size");
-
- power = pow2_higher_or_eq(size);
- power = max_t(unsigned int, 2u, power);
- if (power != size) {
- WARN("using the next power of two for buffer size = %u\n", power);
- }
-
- ltt_lock_traces();
- trace = _ltt_trace_find_setup(trace_name);
- if (trace == NULL) {
- ERR("cannot find trace!");
- retval = -ENODATA;
- goto unlock_traces;
- }
-
- channel = find_channel(ch_name, trace);
- if (!channel) {
- ERR("unable to find channel");
- retval = -ENODATA;
- goto unlock_traces;
- }
-
- channel->subbuf_size = power;
- DBG("the set_subbuf_size for the requested channel is %zu", channel->subbuf_size);
-
-unlock_traces:
- ltt_unlock_traces();
-
- return retval;
-}
-
-static int set_subbuf_num(const char *trace_name, const char *ch_name,
- unsigned int num)
-{
- struct ust_trace *trace;
- struct ust_channel *channel;
- int retval = 0;
-
- DBG("set_subbuf_num");
-
- if (num < 2) {
- ERR("subbuffer count should be greater than 2");
- return -EINVAL;
- }
-
- ltt_lock_traces();
- trace = _ltt_trace_find_setup(trace_name);
- if (trace == NULL) {
- ERR("cannot find trace!");
- retval = -ENODATA;
- goto unlock_traces;
- }
-
- channel = find_channel(ch_name, trace);
- if (!channel) {
- ERR("unable to find channel");
- retval = -ENODATA;
- goto unlock_traces;
- }
-
- channel->subbuf_cnt = num;
- DBG("the set_subbuf_cnt for the requested channel is %u", channel->subbuf_cnt);
-
-unlock_traces:
- ltt_unlock_traces();
- return retval;
-}
-
-static int get_subbuffer(const char *trace_name, const char *ch_name,
- int ch_cpu, long *consumed_old)
-{
- int retval = 0;
- struct ust_trace *trace;
- struct ust_channel *channel;
- struct ust_buffer *buf;
-
- DBG("get_subbuf");
-
- *consumed_old = 0;
-
- ltt_lock_traces();
- trace = _ltt_trace_find(trace_name);
-
- if (!trace) {
- DBG("Cannot find trace. It was likely destroyed by the user.");
- retval = -ENODATA;
- goto unlock_traces;
- }
-
- channel = find_channel(ch_name, trace);
- if (!channel) {
- ERR("unable to find channel");
- retval = -ENODATA;
- goto unlock_traces;
- }
-
- buf = channel->buf[ch_cpu];
-
- retval = ust_buffers_get_subbuf(buf, consumed_old);
- if (retval < 0) {
- WARN("missed buffer?");
- }
-
-unlock_traces:
- ltt_unlock_traces();
-
- return retval;
-}
-
-
-static int notify_buffer_mapped(const char *trace_name,
- const char *ch_name,
- int ch_cpu)
-{
- int retval = 0;
- struct ust_trace *trace;
- struct ust_channel *channel;
- struct ust_buffer *buf;
-
- DBG("get_buffer_fd");
-
- ltt_lock_traces();
- trace = _ltt_trace_find(trace_name);
-
- if (!trace) {
- retval = -ENODATA;
- DBG("Cannot find trace. It was likely destroyed by the user.");
- goto unlock_traces;
- }
-
- channel = find_channel(ch_name, trace);
- if (!channel) {
- retval = -ENODATA;
- ERR("unable to find channel");
- goto unlock_traces;
- }
-
- buf = channel->buf[ch_cpu];
-
- /* Being here is the proof the daemon has mapped the buffer in its
- * memory. We may now decrement buffers_to_export.
- */
- if (uatomic_read(&buf->consumed) == 0) {
- DBG("decrementing buffers_to_export");
- CMM_STORE_SHARED(buffers_to_export, CMM_LOAD_SHARED(buffers_to_export)-1);
- }
-
-unlock_traces:
- ltt_unlock_traces();
-
- return retval;
-}
-
-static int put_subbuffer(const char *trace_name, const char *ch_name,
- int ch_cpu, long consumed_old)
-{
- int retval = 0;
- struct ust_trace *trace;
- struct ust_channel *channel;
- struct ust_buffer *buf;
-
- DBG("put_subbuf");
-
- ltt_lock_traces();
- trace = _ltt_trace_find(trace_name);
-
- if (!trace) {
- retval = -ENODATA;
- DBG("Cannot find trace. It was likely destroyed by the user.");
- goto unlock_traces;
- }
-
- channel = find_channel(ch_name, trace);
- if (!channel) {
- retval = -ENODATA;
- ERR("unable to find channel");
- goto unlock_traces;
- }
-
- buf = channel->buf[ch_cpu];
-
- retval = ust_buffers_put_subbuf(buf, consumed_old);
- if (retval < 0) {
- WARN("ust_buffers_put_subbuf: error (subbuf=%s_%d)",
- ch_name, ch_cpu);
- } else {
- DBG("ust_buffers_put_subbuf: success (subbuf=%s_%d)",
- ch_name, ch_cpu);
- }
-
-unlock_traces:
- ltt_unlock_traces();
-
- return retval;
-}
-
-static void release_listener_mutex(void *ptr)
-{
- pthread_mutex_unlock(&listener_thread_data_mutex);
-}
-
-static void listener_cleanup(void *ptr)
-{
- pthread_mutex_lock(&listen_sock_mutex);
- if (listen_sock) {
- ustcomm_del_named_sock(listen_sock, 0);
- listen_sock = NULL;
- }
- pthread_mutex_unlock(&listen_sock_mutex);
-}
-
-static int force_subbuf_switch(const char *trace_name)
-{
- struct ust_trace *trace;
- int i, j, retval = 0;
-
- ltt_lock_traces();
- trace = _ltt_trace_find(trace_name);
- if (!trace) {
- retval = -ENODATA;
- DBG("Cannot find trace. It was likely destroyed by the user.");
- goto unlock_traces;
- }
-
- for (i = 0; i < trace->nr_channels; i++) {
- for (j = 0; j < trace->channels[i].n_cpus; j++) {
- ltt_force_switch(trace->channels[i].buf[j],
- FORCE_FLUSH);
- }
- }
-
-unlock_traces:
- ltt_unlock_traces();
-
- return retval;
-}
-
-static int process_trace_cmd(int command, char *trace_name)
-{
- int result;
- char trace_type[] = "ustrelay";
-
- switch(command) {
- case START:
- /* start is an operation that setups the trace, allocates it and starts it */
- result = ltt_trace_setup(trace_name);
- if (result < 0) {
- ERR("ltt_trace_setup failed");
- return result;
- }
-
- result = ltt_trace_set_type(trace_name, trace_type);
- if (result < 0) {
- ERR("ltt_trace_set_type failed");
- return result;
- }
-
- result = ltt_trace_alloc(trace_name);
- if (result < 0) {
- ERR("ltt_trace_alloc failed");
- return result;
- }
-
- inform_consumer_daemon(trace_name);
-
- result = ltt_trace_start(trace_name);
- if (result < 0) {
- ERR("ltt_trace_start failed");
- return result;
- }
-
- return 0;
- case SETUP_TRACE:
- DBG("trace setup");
-
- result = ltt_trace_setup(trace_name);
- if (result < 0) {
- ERR("ltt_trace_setup failed");
- return result;
- }
-
- result = ltt_trace_set_type(trace_name, trace_type);
- if (result < 0) {
- ERR("ltt_trace_set_type failed");
- return result;
- }
-
- return 0;
- case ALLOC_TRACE:
- DBG("trace alloc");
-
- result = ltt_trace_alloc(trace_name);
- if (result < 0) {
- ERR("ltt_trace_alloc failed");
- return result;
- }
- inform_consumer_daemon(trace_name);
-
- return 0;
-
- case CREATE_TRACE:
- DBG("trace create");
-
- result = ltt_trace_setup(trace_name);
- if (result < 0) {
- ERR("ltt_trace_setup failed");
- return result;
- }
-
- result = ltt_trace_set_type(trace_name, trace_type);
- if (result < 0) {
- ERR("ltt_trace_set_type failed");
- return result;
- }
-
- return 0;
- case START_TRACE:
- DBG("trace start");
-
- result = ltt_trace_alloc(trace_name);
- if (result < 0) {
- ERR("ltt_trace_alloc failed");
- return result;
- }
- if (!result) {
- inform_consumer_daemon(trace_name);
- }
-
- result = ltt_trace_start(trace_name);
- if (result < 0) {
- ERR("ltt_trace_start failed");
- return result;
- }
-
- return 0;
- case STOP_TRACE:
- DBG("trace stop");
-
- result = ltt_trace_stop(trace_name);
- if (result < 0) {
- ERR("ltt_trace_stop failed");
- return result;
- }
-
- return 0;
- case DESTROY_TRACE:
- DBG("trace destroy");
-
- result = ltt_trace_destroy(trace_name, 0);
- if (result < 0) {
- ERR("ltt_trace_destroy failed");
- return result;
- }
- return 0;
- case FORCE_SUBBUF_SWITCH:
- DBG("force switch");
-
- result = force_subbuf_switch(trace_name);
- if (result < 0) {
- ERR("force_subbuf_switch failed");
- return result;
- }
- return 0;
- }
-
- return 0;
-}
-
-
-static void process_channel_cmd(int sock, int command,
- struct ustcomm_channel_info *ch_inf)
-{
- struct ustcomm_header _reply_header;
- struct ustcomm_header *reply_header = &_reply_header;
- struct ustcomm_channel_info *reply_msg =
- (struct ustcomm_channel_info *)send_buffer;
- int result, offset = 0, num, size;
-
- memset(reply_header, 0, sizeof(*reply_header));
-
- switch (command) {
- case GET_SUBBUF_NUM_SIZE:
- result = get_subbuf_num_size(ch_inf->trace,
- ch_inf->channel,
- &num, &size);
- if (result < 0) {
- reply_header->result = result;
- break;
- }
-
- reply_msg->channel = USTCOMM_POISON_PTR;
- reply_msg->subbuf_num = num;
- reply_msg->subbuf_size = size;
-
-
- reply_header->size = COMPUTE_MSG_SIZE(reply_msg, offset);
-
- break;
- case SET_SUBBUF_NUM:
- reply_header->result = set_subbuf_num(ch_inf->trace,
- ch_inf->channel,
- ch_inf->subbuf_num);
-
- break;
- case SET_SUBBUF_SIZE:
- reply_header->result = set_subbuf_size(ch_inf->trace,
- ch_inf->channel,
- ch_inf->subbuf_size);
-
-
- break;
- }
- if (ustcomm_send(sock, reply_header, (char *)reply_msg) < 0) {
- ERR("ustcomm_send failed");
- }
-}
-
-static void process_buffer_cmd(int sock, int command,
- struct ustcomm_buffer_info *buf_inf)
-{
- struct ustcomm_header _reply_header;
- struct ustcomm_header *reply_header = &_reply_header;
- struct ustcomm_buffer_info *reply_msg =
- (struct ustcomm_buffer_info *)send_buffer;
- int result, offset = 0, buf_shmid, buf_struct_shmid, buf_pipe_fd;
- long consumed_old;
-
- memset(reply_header, 0, sizeof(*reply_header));
-
- switch (command) {
- case GET_BUF_SHMID_PIPE_FD:
- result = get_buffer_shmid_pipe_fd(buf_inf->trace,
- buf_inf->channel,
- buf_inf->ch_cpu,
- &buf_shmid,
- &buf_struct_shmid,
- &buf_pipe_fd);
- if (result < 0) {
- reply_header->result = result;
- break;
- }
-
- reply_msg->channel = USTCOMM_POISON_PTR;
- reply_msg->buf_shmid = buf_shmid;
- reply_msg->buf_struct_shmid = buf_struct_shmid;
-
- reply_header->size = COMPUTE_MSG_SIZE(reply_msg, offset);
- reply_header->fd_included = 1;
-
- if (ustcomm_send_fd(sock, reply_header, (char *)reply_msg,
- &buf_pipe_fd) < 0) {
- ERR("ustcomm_send failed");
- }
- return;
-
- case NOTIFY_BUF_MAPPED:
- reply_header->result =
- notify_buffer_mapped(buf_inf->trace,
- buf_inf->channel,
- buf_inf->ch_cpu);
- break;
- case GET_SUBBUFFER:
- result = get_subbuffer(buf_inf->trace, buf_inf->channel,
- buf_inf->ch_cpu, &consumed_old);
- if (result < 0) {
- reply_header->result = result;
- break;
- }
-
- reply_msg->channel = USTCOMM_POISON_PTR;
- reply_msg->consumed_old = consumed_old;
-
- reply_header->size = COMPUTE_MSG_SIZE(reply_msg, offset);
-
- break;
- case PUT_SUBBUFFER:
- result = put_subbuffer(buf_inf->trace, buf_inf->channel,
- buf_inf->ch_cpu,
- buf_inf->consumed_old);
- reply_header->result = result;
-
- break;
- }
-
- if (ustcomm_send(sock, reply_header, (char *)reply_msg) < 0) {
- ERR("ustcomm_send failed");
- }
-
-}
-
-static void process_ust_marker_cmd(int sock, int command,
- struct ustcomm_ust_marker_info *ust_marker_inf)
-{
- struct ustcomm_header _reply_header;
- struct ustcomm_header *reply_header = &_reply_header;
- int result = 0;
-
- memset(reply_header, 0, sizeof(*reply_header));
-
- switch(command) {
- case ENABLE_MARKER:
-
- result = ltt_ust_marker_connect(ust_marker_inf->channel,
- ust_marker_inf->ust_marker,
- "default");
- if (result < 0) {
- WARN("could not enable ust_marker; channel=%s,"
- " name=%s",
- ust_marker_inf->channel,
- ust_marker_inf->ust_marker);
-
- }
- break;
- case DISABLE_MARKER:
- result = ltt_ust_marker_disconnect(ust_marker_inf->channel,
- ust_marker_inf->ust_marker,
- "default");
- if (result < 0) {
- WARN("could not disable ust_marker; channel=%s,"
- " name=%s",
- ust_marker_inf->channel,
- ust_marker_inf->ust_marker);
- }
- break;
- }
-
- reply_header->result = result;
-
- if (ustcomm_send(sock, reply_header, NULL) < 0) {
- ERR("ustcomm_send failed");
- }
-
-}
-static void process_client_cmd(struct ustcomm_header *recv_header,
- char *recv_buf, int sock)
-{
- int result;
- struct ustcomm_header _reply_header;
- struct ustcomm_header *reply_header = &_reply_header;
- char *send_buf = send_buffer;
-
- memset(reply_header, 0, sizeof(*reply_header));
- memset(send_buf, 0, sizeof(send_buffer));
-
- switch(recv_header->command) {
- case GET_SUBBUF_NUM_SIZE:
- case SET_SUBBUF_NUM:
- case SET_SUBBUF_SIZE:
- {
- struct ustcomm_channel_info *ch_inf;
- ch_inf = (struct ustcomm_channel_info *)recv_buf;
- result = ustcomm_unpack_channel_info(ch_inf);
- if (result < 0) {
- ERR("couldn't unpack channel info");
- reply_header->result = -EINVAL;
- goto send_response;
- }
- process_channel_cmd(sock, recv_header->command, ch_inf);
- return;
- }
- case GET_BUF_SHMID_PIPE_FD:
- case NOTIFY_BUF_MAPPED:
- case GET_SUBBUFFER:
- case PUT_SUBBUFFER:
- {
- struct ustcomm_buffer_info *buf_inf;
- buf_inf = (struct ustcomm_buffer_info *)recv_buf;
- result = ustcomm_unpack_buffer_info(buf_inf);
- if (result < 0) {
- ERR("couldn't unpack buffer info");
- reply_header->result = -EINVAL;
- goto send_response;
- }
- process_buffer_cmd(sock, recv_header->command, buf_inf);
- return;
- }
- case ENABLE_MARKER:
- case DISABLE_MARKER:
- {
- struct ustcomm_ust_marker_info *ust_marker_inf;
- ust_marker_inf = (struct ustcomm_ust_marker_info *)recv_buf;
- result = ustcomm_unpack_ust_marker_info(ust_marker_inf);
- if (result < 0) {
- ERR("couldn't unpack ust_marker info");
- reply_header->result = -EINVAL;
- goto send_response;
- }
- process_ust_marker_cmd(sock, recv_header->command, ust_marker_inf);
- return;
- }
- case LIST_MARKERS:
- {
- char *ptr;
- size_t size;
- FILE *fp;
-
- fp = open_memstream(&ptr, &size);
- if (fp == NULL) {
- ERR("opening memstream failed");
- return;
- }
- print_ust_marker(fp);
- fclose(fp);
-
- reply_header->size = size + 1; /* Include final \0 */
-
- result = ustcomm_send(sock, reply_header, ptr);
-
- free(ptr);
-
- if (result < 0) {
- PERROR("failed to send ust_marker list");
- }
-
- break;
- }
- case LIST_TRACE_EVENTS:
- {
- char *ptr;
- size_t size;
- FILE *fp;
-
- fp = open_memstream(&ptr, &size);
- if (fp == NULL) {
- ERR("opening memstream failed");
- return;
- }
- print_trace_events(fp);
- fclose(fp);
-
- reply_header->size = size + 1; /* Include final \0 */
-
- result = ustcomm_send(sock, reply_header, ptr);
-
- free(ptr);
-
- if (result < 0) {
- ERR("list_trace_events failed");
- return;
- }
-
- break;
- }
- case LOAD_PROBE_LIB:
- {
- char *libfile;
-
- /* FIXME: No functionality at all... */
- libfile = recv_buf;
-
- DBG("load_probe_lib loading %s", libfile);
-
- break;
- }
- case GET_PIDUNIQUE:
- {
- struct ustcomm_pidunique *pid_msg;
- pid_msg = (struct ustcomm_pidunique *)send_buf;
-
- pid_msg->pidunique = pidunique;
- reply_header->size = sizeof(pid_msg);
-
- goto send_response;
-
- }
- case GET_SOCK_PATH:
- {
- struct ustcomm_single_field *sock_msg;
- char *sock_path_env;
-
- sock_msg = (struct ustcomm_single_field *)send_buf;
-
- sock_path_env = getenv("UST_DAEMON_SOCKET");
-
- if (!sock_path_env) {
- result = ustcomm_pack_single_field(reply_header,
- sock_msg,
- SOCK_DIR "/ustconsumer");
-
- } else {
- result = ustcomm_pack_single_field(reply_header,
- sock_msg,
- sock_path_env);
- }
- reply_header->result = result;
-
- goto send_response;
- }
- case SET_SOCK_PATH:
- {
- struct ustcomm_single_field *sock_msg;
- sock_msg = (struct ustcomm_single_field *)recv_buf;
- result = ustcomm_unpack_single_field(sock_msg);
- if (result < 0) {
- reply_header->result = -EINVAL;
- goto send_response;
- }
-
- reply_header->result = setenv("UST_DAEMON_SOCKET",
- sock_msg->field, 1);
-
- goto send_response;
- }
- case START:
- case SETUP_TRACE:
- case ALLOC_TRACE:
- case CREATE_TRACE:
- case START_TRACE:
- case STOP_TRACE:
- case DESTROY_TRACE:
- case FORCE_SUBBUF_SWITCH:
- {
- struct ustcomm_single_field *trace_inf =
- (struct ustcomm_single_field *)recv_buf;
-
- result = ustcomm_unpack_single_field(trace_inf);
- if (result < 0) {
- ERR("couldn't unpack trace info");
- reply_header->result = -EINVAL;
- goto send_response;
- }
-
- reply_header->result =
- process_trace_cmd(recv_header->command,
- trace_inf->field);
- goto send_response;
-
- }
- default:
- reply_header->result = -EINVAL;
-
- goto send_response;
- }
-
- return;
-
-send_response:
- ustcomm_send(sock, reply_header, send_buf);
-}
-
-#define MAX_EVENTS 10
-
-void *listener_main(void *p)
-{
- struct ustcomm_sock *epoll_sock;
- struct epoll_event events[MAX_EVENTS];
- struct sockaddr addr;
- int accept_fd, nfds, result, i, addr_size;
-
- DBG("LISTENER");
-
- pthread_cleanup_push(listener_cleanup, NULL);
-
- for(;;) {
- nfds = epoll_wait(epoll_fd, events, MAX_EVENTS, -1);
- if (nfds == -1) {
- PERROR("listener_main: epoll_wait failed");
- continue;
- }
-
- for (i = 0; i < nfds; i++) {
- pthread_mutex_lock(&listener_thread_data_mutex);
- pthread_cleanup_push(release_listener_mutex, NULL);
- epoll_sock = (struct ustcomm_sock *)events[i].data.ptr;
- if (epoll_sock == listen_sock) {
- addr_size = sizeof(struct sockaddr);
- accept_fd = accept(epoll_sock->fd,
- &addr,
- (socklen_t *)&addr_size);
- if (accept_fd == -1) {
- PERROR("listener_main: accept failed");
- continue;
- }
- ustcomm_init_sock(accept_fd, epoll_fd,
- &ust_socks);
- } else {
- memset(receive_header, 0,
- sizeof(*receive_header));
- memset(receive_buffer, 0,
- sizeof(receive_buffer));
- result = ustcomm_recv(epoll_sock->fd,
- receive_header,
- receive_buffer);
- if (result == 0) {
- ustcomm_del_sock(epoll_sock, 0);
- } else {
- process_client_cmd(receive_header,
- receive_buffer,
- epoll_sock->fd);
- }
- }
- pthread_cleanup_pop(1); /* release listener mutex */
- }
- }
-
- pthread_cleanup_pop(1);
-}
-
-/* These should only be accessed in the parent thread,
- * not the listener.
- */
-static volatile sig_atomic_t have_listener = 0;
-static pthread_t listener_thread;
-
-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");
- }
-
- /* 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;
- }
-}
-
-#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 ust_marker *m)
-{
- int result;
-
- char* concat_name = NULL;
- const char *probe_name = "default";
-
- 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 (ust_marker %s/%s)",
- m->channel, m->name);
- return;
- }
- if (regexec(&autoprobe_regex, concat_name, 0, NULL, 0)) {
- free(concat_name);
- return;
- }
- free(concat_name);
- }
-
- result = ltt_ust_marker_connect(m->channel, m->name, probe_name);
- if (result && result != -EEXIST)
- ERR("ltt_ust_marker_connect (ust_marker = %s/%s, errno = %d)", m->channel, m->name, -result);
-
- DBG("auto connected ust_marker %s (addr: %p) %s to probe default", m->channel, m, m->name);
-
-}
-
-static struct ustcomm_sock * init_app_socket(int epoll_fd)
-{
- char *dir_name, *sock_name;
- int result;
- struct ustcomm_sock *sock = NULL;
- time_t mtime;
-
- dir_name = ustcomm_user_sock_dir();
- if (!dir_name)
- return NULL;
-
- mtime = ustcomm_pid_st_mtime(getpid());
- if (!mtime) {
- goto free_dir_name;
- }
-
- result = asprintf(&sock_name, "%s/%d.%ld", dir_name,
- (int) getpid(), (long) mtime);
- if (result < 0) {
- ERR("string overflow allocating socket name, "
- "UST thread bailing");
- goto free_dir_name;
- }
-
- result = ensure_dir_exists(dir_name, S_IRWXU);
- if (result == -1) {
- ERR("Unable to create socket directory %s, UST thread bailing",
- dir_name);
- goto free_sock_name;
- }
-
- sock = ustcomm_init_named_socket(sock_name, epoll_fd);
- if (!sock) {
- ERR("Error initializing named socket (%s). Check that directory"
- "exists and that it is writable. UST thread bailing", sock_name);
- goto free_sock_name;
- }
-
-free_sock_name:
- free(sock_name);
-free_dir_name:
- free(dir_name);
-
- return sock;
-}
-
-static void __attribute__((constructor)) init()
-{
- struct timespec ts;
- 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).
- */
- pidunique = make_pidunique();
- processpid = getpid();
-
- DBG("Tracectl constructor");
-
- /* Set up epoll */
- epoll_fd = epoll_create(MAX_EVENTS);
- if (epoll_fd == -1) {
- ERR("epoll_create failed, tracing shutting down");
- return;
- }
-
- /* Create the socket */
- listen_sock = init_app_socket(epoll_fd);
- if (!listen_sock) {
- ERR("failed to create application socket,"
- " tracing shutting down");
- return;
- }
-
- create_listener();
-
- /* Get clock the clock source type */
-
- /* Default clock source */
- ust_clock_source = CLOCK_TRACE;
- if (clock_gettime(ust_clock_source, &ts) != 0) {
- ust_clock_source = CLOCK_MONOTONIC;
- DBG("UST traces will not be synchronized with LTTng traces");
- }
-
- if (getenv("UST_TRACE") || getenv("UST_AUTOPROBE")) {
- /* Ensure ust_marker control is initialized */
- init_ust_marker_control();
- }
-
- autoprobe_val = getenv("UST_AUTOPROBE");
- if (autoprobe_val) {
- struct ust_marker_iter iter;
-
- DBG("Autoprobe enabled.");
-
- /* first, set the callback that will connect the
- * probe on new ust_marker
- */
- 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;
- }
-
- ust_marker_set_new_ust_marker_cb(auto_probe_connect);
-
- /* Now, connect the probes that were already registered. */
- ust_marker_iter_reset(&iter);
- ust_marker_iter_start(&iter);
-
- DBG("now iterating on ust_marker already registered");
- while (iter.ust_marker) {
- DBG("now iterating on ust_marker %s", (*iter.ust_marker)->name);
- auto_probe_connect(*iter.ust_marker);
- ust_marker_iter_next(&iter);
- }
- ust_marker_iter_stop(&iter);
- }
-
- if (getenv("UST_OVERWRITE")) {
- int val = atoi(getenv("UST_OVERWRITE"));
- if (val == 0 || val == 1) {
- CMM_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) {
- CMM_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";
-
- DBG("starting early tracing");
-
- /* Ensure buffers are initialized, for the transport to be available.
- * We are about to set a trace type and it will fail without this.
- */
- init_ustrelay_transport();
-
- /* FIXME: When starting early tracing (here), depending on the
- * order of constructors, it is very well possible some ust_marker
- * sections are not yet registered. Because of this, some
- * channels may not be registered. Yet, we are about to ask the
- * daemon to collect the channels. Channels which are not yet
- * registered will not be collected.
- *
- * Currently, in LTTng, there is no way to add a channel after
- * trace start. The reason for this is that it induces complex
- * concurrency issues on the trace structures, which can only
- * be resolved using RCU. This has not been done yet. As a
- * workaround, we are forcing the registration of the "ust"
- * channel here. This is the only channel (apart from metadata)
- * that can be reliably used in early tracing.
- *
- * Non-early tracing does not have this problem and can use
- * arbitrary channel names.
- */
- ltt_channels_register("ust");
-
- result = ltt_trace_setup(trace_name);
- if (result < 0) {
- ERR("ltt_trace_setup failed");
- return;
- }
-
- result = ltt_trace_set_type(trace_name, trace_type);
- if (result < 0) {
- ERR("ltt_trace_set_type failed");
- return;
- }
-
- result = ltt_trace_alloc(trace_name);
- if (result < 0) {
- ERR("ltt_trace_alloc failed");
- return;
- }
-
- result = ltt_trace_start(trace_name);
- if (result < 0) {
- ERR("ltt_trace_start failed");
- return;
- }
-
- /* Do this after the trace is started in order to avoid creating confusion
- * if the trace fails to start. */
- inform_consumer_daemon(trace_name);
- }
-
- return;
-
- /* should decrementally destroy stuff if error */
-
-}
-
-/* This is only called if we terminate normally, not with an unhandled signal,
- * 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 trace running, finish it */
-
- DBG("destructor stopping traces");
-
- result = ltt_trace_stop("auto");
- if (result == -1) {
- ERR("ltt_trace_stop error");
- }
-
- result = ltt_trace_destroy("auto", 0);
- if (result == -1) {
- ERR("ltt_trace_destroy error");
- }
-}
-
-static int trace_recording(void)
-{
- int retval = 0;
- struct ust_trace *trace;
-
- ltt_lock_traces();
-
- cds_list_for_each_entry(trace, <t_traces.head, list) {
- if (trace->active) {
- retval = 1;
- break;
- }
- }
-
- ltt_unlock_traces();
-
- return retval;
-}
-
-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;
-}
-
-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));
- }
- result = pthread_join(listener_thread, NULL);
- if (result != 0) {
- ERR("pthread_join: %s", strerror(result));
- }
-}
-
-/* This destructor keeps the process alive for a few seconds in order
- * to leave time for ustconsumer 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 (processpid != getpid()) {
- return;
- }
-
- if (trace_recording() && CMM_LOAD_SHARED(buffers_to_export)) {
- int total = 0;
- DBG("Keeping process alive for consumer daemon...");
- while (CMM_LOAD_SHARED(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();
-
- /* Ask the listener to stop and clean up. */
- stop_listener();
-}
-
-void ust_potential_exec(void)
-{
- ust_marker(potential_exec, UST_MARKER_NOARGS);
-
- DBG("test");
-
- keepalive();
-}
-
-/* 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.
- *
- * Signals should be disabled before the fork and reenabled only after
- * this call in order to guarantee tracing is not started before ust_fork()
- * sanitizes the new process.
- */
-
-static void ust_fork(void)
-{
- struct ustcomm_sock *sock, *sock_tmp;
- struct ust_trace *trace, *trace_tmp;
- int result;
-
- /* FIXME: technically, the locks could have been taken before the fork */
- DBG("ust: forking");
-
- /* Get the pid of the new process */
- processpid = getpid();
-
- /*
- * FIXME: This could be prettier, we loop over the list twice and
- * following good locking practice should lock around the loop
- */
- cds_list_for_each_entry_safe(trace, trace_tmp, <t_traces.head, list) {
- ltt_trace_stop(trace->trace_name);
- }
-
- /* Delete all active connections, but leave them in the epoll set */
- cds_list_for_each_entry_safe(sock, sock_tmp, &ust_socks, list) {
- ustcomm_del_sock(sock, 1);
- }
-
- /*
- * FIXME: This could be prettier, we loop over the list twice and
- * following good locking practice should lock around the loop
- */
- cds_list_for_each_entry_safe(trace, trace_tmp, <t_traces.head, list) {
- ltt_trace_destroy(trace->trace_name, 1);
- }
-
- /* Clean up the listener socket and epoll, keeping the socket file */
- if (listen_sock) {
- ustcomm_del_named_sock(listen_sock, 1);
- listen_sock = NULL;
- }
- close(epoll_fd);
-
- /* Re-start the launch sequence */
- CMM_STORE_SHARED(buffers_to_export, 0);
- have_listener = 0;
-
- /* Set up epoll */
- epoll_fd = epoll_create(MAX_EVENTS);
- if (epoll_fd == -1) {
- ERR("epoll_create failed, tracing shutting down");
- return;
- }
-
- /* Create the socket */
- listen_sock = init_app_socket(epoll_fd);
- if (!listen_sock) {
- ERR("failed to create application socket,"
- " tracing shutting down");
- return;
- }
- create_listener();
- 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");
-}
-
-void ust_before_fork(ust_fork_info_t *fork_info)
-{
- /* Disable signals. This is to avoid that the child
- * intervenes before it is properly setup for tracing. It is
- * safer to disable all signals, because then we know we are not
- * breaking anything by restoring the original mask.
- */
- sigset_t all_sigs;
- int result;
-
- /* FIXME:
- - only do this if tracing is active
- */
-
- /* Disable signals */
- sigfillset(&all_sigs);
- result = sigprocmask(SIG_BLOCK, &all_sigs, &fork_info->orig_sigs);
- if (result == -1) {
- PERROR("sigprocmask");
- return;
- }
-
- /*
- * Take the fork lock to make sure we are not in the middle of
- * something in the listener thread.
- */
- pthread_mutex_lock(&listener_thread_data_mutex);
- /*
- * Hold listen_sock_mutex to protect from listen_sock teardown.
- */
- pthread_mutex_lock(&listen_sock_mutex);
- rcu_bp_before_fork();
-}
-
-/* Don't call this function directly in a traced program */
-static void ust_after_fork_common(ust_fork_info_t *fork_info)
-{
- int result;
-
- pthread_mutex_unlock(&listen_sock_mutex);
- pthread_mutex_unlock(&listener_thread_data_mutex);
- /* Restore signals */
- result = sigprocmask(SIG_SETMASK, &fork_info->orig_sigs, NULL);
- if (result == -1) {
- PERROR("sigprocmask");
- return;
- }
-}
-
-void ust_after_fork_parent(ust_fork_info_t *fork_info)
-{
- rcu_bp_after_fork_parent();
- /* Release mutexes and reenable signals */
- ust_after_fork_common(fork_info);
-}
-
-void ust_after_fork_child(ust_fork_info_t *fork_info)
-{
- /* Release urcu mutexes */
- rcu_bp_after_fork_child();
-
- /* Sanitize the child */
- ust_fork();
-
- /* Release mutexes and reenable signals */
- ust_after_fork_common(fork_info);
-}
-