#define _GNU_SOURCE
#include <stdio.h>
+#include <endian.h>
#include <urcu/list.h>
+#include <urcu/hlist.h>
#include <pthread.h>
#include <urcu-bp.h>
#include <urcu/compiler.h>
#include <urcu/uatomic.h>
#include <uuid/uuid.h>
-#include <ust/tracepoint.h>
+#include <lttng/tracepoint.h>
#include <errno.h>
#include <sys/shm.h>
#include <sys/ipc.h>
-#include <ust/lttng-events.h>
-#include <ust/usterr-signal-safe.h>
-#include "ust/core.h"
+#include <lttng/ust-events.h>
+#include <lttng/usterr-signal-safe.h>
+#include "lttng/core.h"
#include "ltt-tracer.h"
-#include "ust/wait.h"
+#include "ltt-tracer-core.h"
+#include "lttng/wait.h"
#include "../libringbuffer/shm.h"
+typedef u32 uint32_t;
+#include <lttng/kcompat/jhash.h>
+
+/*
+ * The sessions mutex is the centralized mutex across UST tracing
+ * control and probe registration. All operations within this file are
+ * called by the communication thread, under ust_lock protection.
+ */
+static DEFINE_MUTEX(sessions_mutex);
+
+void ust_lock(void)
+{
+ pthread_mutex_lock(&sessions_mutex);
+}
+
+void ust_unlock(void)
+{
+ pthread_mutex_unlock(&sessions_mutex);
+}
+
static CDS_LIST_HEAD(sessions);
static CDS_LIST_HEAD(ltt_transport_list);
-static DEFINE_MUTEX(sessions_mutex);
+
+/*
+ * Pending probes hash table, containing the registered ltt events for
+ * which tracepoint probes are still missing. Protected by the sessions
+ * mutex.
+ */
+#define PENDING_PROBE_HASH_BITS 6
+#define PENDING_PROBE_HASH_SIZE (1 << PENDING_PROBE_HASH_BITS)
+static struct cds_hlist_head pending_probe_table[PENDING_PROBE_HASH_SIZE];
+
+struct ust_pending_probe {
+ struct ltt_event *event;
+ struct cds_hlist_node node;
+ char name[];
+};
static void _ltt_event_destroy(struct ltt_event *event);
static void _ltt_channel_destroy(struct ltt_channel *chan);
static
int _ltt_session_metadata_statedump(struct ltt_session *session);
+/*
+ * called at event creation if probe is missing.
+ * called with session mutex held.
+ */
+static
+int add_pending_probe(struct ltt_event *event, const char *name)
+{
+ struct cds_hlist_head *head;
+ struct ust_pending_probe *e;
+ size_t name_len = strlen(name) + 1;
+ u32 hash = jhash(name, name_len - 1, 0);
+
+ head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)];
+ e = zmalloc(sizeof(struct ust_pending_probe) + name_len);
+ if (!e)
+ return -ENOMEM;
+ memcpy(&e->name[0], name, name_len);
+ cds_hlist_add_head(&e->node, head);
+ e->event = event;
+ event->pending_probe = e;
+ return 0;
+}
+
+/*
+ * remove a pending probe. called when at event teardown and when an
+ * event is fixed (probe is loaded).
+ * called with session mutex held.
+ */
+static
+void remove_pending_probe(struct ust_pending_probe *e)
+{
+ if (!e)
+ return;
+ cds_hlist_del(&e->node);
+ free(e);
+}
+
+/*
+ * Called at library load: connect the probe on the events pending on
+ * probe load.
+ * called with session mutex held.
+ */
+int pending_probe_fix_events(const struct lttng_event_desc *desc)
+{
+ struct cds_hlist_head *head;
+ struct cds_hlist_node *node, *p;
+ struct ust_pending_probe *e;
+ const char *name = desc->name;
+ size_t name_len = strlen(name) + 1;
+ u32 hash = jhash(name, name_len - 1, 0);
+ int ret = 0;
+
+ head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)];
+ cds_hlist_for_each_entry_safe(e, node, p, head, node) {
+ struct ltt_event *event;
+ struct ltt_channel *chan;
+
+ if (strcmp(name, e->name))
+ continue;
+ event = e->event;
+ chan = event->chan;
+ assert(!event->desc);
+ event->desc = desc;
+ event->pending_probe = NULL;
+ remove_pending_probe(e);
+ ret |= __tracepoint_probe_register(name,
+ event->desc->probe_callback,
+ event);
+ if (ret)
+ continue;
+ event->id = chan->free_event_id++;
+ ret |= _ltt_event_metadata_statedump(chan->session, chan,
+ event);
+ }
+ return ret;
+}
+
void synchronize_trace(void)
{
synchronize_rcu();
session = zmalloc(sizeof(struct ltt_session));
if (!session)
return NULL;
- pthread_mutex_lock(&sessions_mutex);
CDS_INIT_LIST_HEAD(&session->chan);
CDS_INIT_LIST_HEAD(&session->events);
uuid_generate(session->uuid);
cds_list_add(&session->list, &sessions);
- pthread_mutex_unlock(&sessions_mutex);
return session;
}
struct ltt_event *event, *tmpevent;
int ret;
- pthread_mutex_lock(&sessions_mutex);
CMM_ACCESS_ONCE(session->active) = 0;
cds_list_for_each_entry(event, &session->events, list) {
ret = _ltt_event_unregister(event);
cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list)
_ltt_channel_destroy(chan);
cds_list_del(&session->list);
- pthread_mutex_unlock(&sessions_mutex);
free(session);
}
int ret = 0;
struct ltt_channel *chan;
- pthread_mutex_lock(&sessions_mutex);
if (session->active) {
ret = -EBUSY;
goto end;
if (ret)
CMM_ACCESS_ONCE(session->active) = 0;
end:
- pthread_mutex_unlock(&sessions_mutex);
return ret;
}
{
int ret = 0;
- pthread_mutex_lock(&sessions_mutex);
if (!session->active) {
ret = -EBUSY;
goto end;
}
CMM_ACCESS_ONCE(session->active) = 0;
end:
- pthread_mutex_unlock(&sessions_mutex);
return ret;
}
void *buf_addr,
size_t subbuf_size, size_t num_subbuf,
unsigned int switch_timer_interval,
- unsigned int read_timer_interval)
+ unsigned int read_timer_interval,
+ int *shm_fd, int *wait_fd,
+ uint64_t *memory_map_size)
{
struct ltt_channel *chan;
struct ltt_transport *transport;
- pthread_mutex_lock(&sessions_mutex);
if (session->been_active)
goto active; /* Refuse to add channel to active session */
transport = ltt_transport_find(transport_name);
*/
transport->ops.channel_create("[lttng]", chan, buf_addr,
subbuf_size, num_subbuf, switch_timer_interval,
- read_timer_interval);
+ read_timer_interval, shm_fd, wait_fd,
+ memory_map_size);
if (!chan->chan)
goto create_error;
chan->enabled = 1;
chan->ops = &transport->ops;
cds_list_add(&chan->list, &session->chan);
- pthread_mutex_unlock(&sessions_mutex);
return chan;
create_error:
nomem:
notransport:
active:
- pthread_mutex_unlock(&sessions_mutex);
return NULL;
}
struct ltt_event *event;
int ret;
- pthread_mutex_lock(&sessions_mutex);
- if (chan->free_event_id == -1UL)
+ if (chan->used_event_id == -1UL)
goto full;
/*
* This is O(n^2) (for each event, the loop is called at event
* creation). Might require a hash if we have lots of events.
*/
cds_list_for_each_entry(event, &chan->session->events, list)
- if (!strcmp(event->desc->name, event_param->name))
+ if (event->desc && !strcmp(event->desc->name, event_param->name))
goto exist;
event = zmalloc(sizeof(struct ltt_event));
if (!event)
goto cache_error;
event->chan = chan;
event->filter = filter;
- event->id = chan->free_event_id++;
+ /*
+ * used_event_id counts the maximum number of event IDs that can
+ * register if all probes register.
+ */
+ chan->used_event_id++;
event->enabled = 1;
event->instrumentation = event_param->instrumentation;
/* Populate ltt_event structure before tracepoint registration. */
switch (event_param->instrumentation) {
case LTTNG_UST_TRACEPOINT:
event->desc = ltt_event_get(event_param->name);
- if (!event->desc)
- goto register_error;
- ret = __tracepoint_probe_register(event_param->name,
- event->desc->probe_callback,
- event);
- if (ret)
- goto register_error;
+ if (event->desc) {
+ ret = __tracepoint_probe_register(event_param->name,
+ event->desc->probe_callback,
+ event);
+ if (ret)
+ goto register_error;
+ event->id = chan->free_event_id++;
+ } else {
+ /*
+ * If the probe is not present, event->desc stays NULL,
+ * waiting for the probe to register, and the event->id
+ * stays unallocated.
+ */
+ ret = add_pending_probe(event, event_param->name);
+ if (ret)
+ goto add_pending_error;
+ }
break;
default:
WARN_ON_ONCE(1);
}
- ret = _ltt_event_metadata_statedump(chan->session, chan, event);
- if (ret)
- goto statedump_error;
+ if (event->desc) {
+ ret = _ltt_event_metadata_statedump(chan->session, chan, event);
+ if (ret)
+ goto statedump_error;
+ }
cds_list_add(&event->list, &chan->session->events);
- pthread_mutex_unlock(&sessions_mutex);
return event;
statedump_error:
- WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name,
- event->desc->probe_callback,
- event));
- ltt_event_put(event->desc);
+ if (event->desc) {
+ WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name,
+ event->desc->probe_callback,
+ event));
+ ltt_event_put(event->desc);
+ }
+add_pending_error:
register_error:
free(event);
cache_error:
exist:
full:
- pthread_mutex_unlock(&sessions_mutex);
return NULL;
}
switch (event->instrumentation) {
case LTTNG_UST_TRACEPOINT:
- ret = __tracepoint_probe_unregister(event->desc->name,
- event->desc->probe_callback,
- event);
- if (ret)
- return ret;
+ if (event->desc) {
+ ret = __tracepoint_probe_unregister(event->desc->name,
+ event->desc->probe_callback,
+ event);
+ if (ret)
+ return ret;
+ } else {
+ remove_pending_probe(event->pending_probe);
+ ret = 0;
+ }
break;
default:
WARN_ON_ONCE(1);
{
switch (event->instrumentation) {
case LTTNG_UST_TRACEPOINT:
- ltt_event_put(event->desc);
+ if (event->desc) {
+ ltt_event_put(event->desc);
+ }
break;
default:
WARN_ON_ONCE(1);
/*
* We have exclusive access to our metadata buffer (protected by the
- * sessions_mutex), so we can do racy operations such as looking for
+ * ust_lock), so we can do racy operations such as looking for
* remaining space left in packet and write, since mutual exclusion
* protects us from concurrent writes.
*/
int lttng_metadata_printf(struct ltt_session *session,
const char *fmt, ...)
{
- struct lib_ring_buffer_ctx ctx;
+ struct lttng_ust_lib_ring_buffer_ctx ctx;
struct ltt_channel *chan = session->metadata;
char *str = NULL;
int ret = 0, waitret;
switch (field->type.atype) {
case atype_integer:
ret = lttng_metadata_printf(session,
- " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s;\n",
+ " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n",
field->type.u.basic.integer.size,
field->type.u.basic.integer.alignment,
field->type.u.basic.integer.signedness,
? "UTF8"
: "ASCII",
field->type.u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if (BYTE_ORDER == BIG_ENDIAN)
field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
#else
field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
break;
case atype_float:
ret = lttng_metadata_printf(session,
- " floating_point { exp_dig = %u; mant_dig = %u; align = %u; } %s;\n",
+ " floating_point { exp_dig = %u; mant_dig = %u; align = %u;%s } _%s;\n",
field->type.u.basic._float.exp_dig,
field->type.u.basic._float.mant_dig,
field->type.u.basic._float.alignment,
-#ifdef __BIG_ENDIAN
+#if (BYTE_ORDER == BIG_ENDIAN)
field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
#else
field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
elem_type = &field->type.u.array.elem_type;
ret = lttng_metadata_printf(session,
- " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s[%u];\n",
+ " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n",
elem_type->u.basic.integer.size,
elem_type->u.basic.integer.alignment,
elem_type->u.basic.integer.signedness,
? "UTF8"
: "ASCII",
elem_type->u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if (BYTE_ORDER == BIG_ENDIAN)
elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
#else
elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
? "UTF8"
: "ASCII"),
length_type->u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if (BYTE_ORDER == BIG_ENDIAN)
length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
#else
length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
return ret;
ret = lttng_metadata_printf(session,
- " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s[ __%s_length ];\n",
+ " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
elem_type->u.basic.integer.size,
(unsigned int) elem_type->u.basic.integer.alignment,
elem_type->u.basic.integer.signedness,
? "UTF8"
: "ASCII"),
elem_type->u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if (BYTE_ORDER == BIG_ENDIAN)
elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
#else
elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
case atype_string:
/* Default encoding is UTF8 */
ret = lttng_metadata_printf(session,
- " string%s %s;\n",
+ " string%s _%s;\n",
field->type.u.basic.string.encoding == lttng_encode_ASCII ?
" { encoding = ASCII; }" : "",
field->name);
return 0;
if (chan == session->metadata)
return 0;
+ /*
+ * Don't print events for which probe load is pending.
+ */
+ if (!event->desc)
+ return 0;
ret = lttng_metadata_printf(session,
"event {\n"
CTF_VERSION_MAJOR,
CTF_VERSION_MINOR,
uuid_s,
-#ifdef __BIG_ENDIAN
+#if (BYTE_ORDER == BIG_ENDIAN)
"be"
#else
"le"
* @transport: transport structure
*
* Registers a transport which can be used as output to extract the data out of
- * LTTng.
+ * LTTng. Called with ust_lock held.
*/
void ltt_transport_register(struct ltt_transport *transport)
{
- pthread_mutex_lock(&sessions_mutex);
cds_list_add_tail(&transport->node, <t_transport_list);
- pthread_mutex_unlock(&sessions_mutex);
}
/**
* ltt_transport_unregister - LTT transport unregistration
* @transport: transport structure
+ * Called with ust_lock held.
*/
void ltt_transport_unregister(struct ltt_transport *transport)
{
- pthread_mutex_lock(&sessions_mutex);
cds_list_del(&transport->node);
- pthread_mutex_unlock(&sessions_mutex);
}
-void ltt_events_exit(void)
+void lttng_ust_events_exit(void)
{
struct ltt_session *session, *tmpsession;
projects / lttng-ust.git / blobdiff