+++ /dev/null
-/*
- * ltt-events.c
- *
- * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * Holds LTTng per-session event registry.
- *
- * Dual LGPL v2.1/GPL v2 license.
- */
-
-#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 <lttng/tracepoint.h>
-#include <errno.h>
-#include <sys/shm.h>
-#include <sys/ipc.h>
-#include <lttng/ust-events.h>
-#include <lttng/usterr-signal-safe.h>
-#include "lttng/core.h"
-#include "ltt-tracer.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);
-
-/*
- * 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_event_unregister(struct ltt_event *event);
-static
-int _ltt_event_metadata_statedump(struct ltt_session *session,
- struct ltt_channel *chan,
- struct ltt_event *event);
-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();
-}
-
-struct ltt_session *ltt_session_create(void)
-{
- struct ltt_session *session;
-
- session = zmalloc(sizeof(struct ltt_session));
- if (!session)
- return NULL;
- CDS_INIT_LIST_HEAD(&session->chan);
- CDS_INIT_LIST_HEAD(&session->events);
- uuid_generate(session->uuid);
- cds_list_add(&session->list, &sessions);
- return session;
-}
-
-void ltt_session_destroy(struct ltt_session *session)
-{
- struct ltt_channel *chan, *tmpchan;
- struct ltt_event *event, *tmpevent;
- int ret;
-
- CMM_ACCESS_ONCE(session->active) = 0;
- cds_list_for_each_entry(event, &session->events, list) {
- ret = _ltt_event_unregister(event);
- WARN_ON(ret);
- }
- synchronize_trace(); /* Wait for in-flight events to complete */
- cds_list_for_each_entry_safe(event, tmpevent, &session->events, list)
- _ltt_event_destroy(event);
- cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list)
- _ltt_channel_destroy(chan);
- cds_list_del(&session->list);
- free(session);
-}
-
-int ltt_session_enable(struct ltt_session *session)
-{
- int ret = 0;
- struct ltt_channel *chan;
-
- if (session->active) {
- ret = -EBUSY;
- goto end;
- }
-
- /*
- * Snapshot the number of events per channel to know the type of header
- * we need to use.
- */
- cds_list_for_each_entry(chan, &session->chan, list) {
- if (chan->header_type)
- continue; /* don't change it if session stop/restart */
- if (chan->free_event_id < 31)
- chan->header_type = 1; /* compact */
- else
- chan->header_type = 2; /* large */
- }
-
- CMM_ACCESS_ONCE(session->active) = 1;
- CMM_ACCESS_ONCE(session->been_active) = 1;
- ret = _ltt_session_metadata_statedump(session);
- if (ret)
- CMM_ACCESS_ONCE(session->active) = 0;
-end:
- return ret;
-}
-
-int ltt_session_disable(struct ltt_session *session)
-{
- int ret = 0;
-
- if (!session->active) {
- ret = -EBUSY;
- goto end;
- }
- CMM_ACCESS_ONCE(session->active) = 0;
-end:
- return ret;
-}
-
-int ltt_channel_enable(struct ltt_channel *channel)
-{
- int old;
-
- if (channel == channel->session->metadata)
- return -EPERM;
- old = uatomic_xchg(&channel->enabled, 1);
- if (old)
- return -EEXIST;
- return 0;
-}
-
-int ltt_channel_disable(struct ltt_channel *channel)
-{
- int old;
-
- if (channel == channel->session->metadata)
- return -EPERM;
- old = uatomic_xchg(&channel->enabled, 0);
- if (!old)
- return -EEXIST;
- return 0;
-}
-
-int ltt_event_enable(struct ltt_event *event)
-{
- int old;
-
- if (event->chan == event->chan->session->metadata)
- return -EPERM;
- old = uatomic_xchg(&event->enabled, 1);
- if (old)
- return -EEXIST;
- return 0;
-}
-
-int ltt_event_disable(struct ltt_event *event)
-{
- int old;
-
- if (event->chan == event->chan->session->metadata)
- return -EPERM;
- old = uatomic_xchg(&event->enabled, 0);
- if (!old)
- return -EEXIST;
- return 0;
-}
-
-static struct ltt_transport *ltt_transport_find(const char *name)
-{
- struct ltt_transport *transport;
-
- cds_list_for_each_entry(transport, <t_transport_list, node) {
- if (!strcmp(transport->name, name))
- return transport;
- }
- return NULL;
-}
-
-struct ltt_channel *ltt_channel_create(struct ltt_session *session,
- const char *transport_name,
- void *buf_addr,
- size_t subbuf_size, size_t num_subbuf,
- unsigned int switch_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;
-
- if (session->been_active)
- goto active; /* Refuse to add channel to active session */
- transport = ltt_transport_find(transport_name);
- if (!transport) {
- DBG("LTTng transport %s not found\n",
- transport_name);
- goto notransport;
- }
- chan = zmalloc(sizeof(struct ltt_channel));
- if (!chan)
- goto nomem;
- chan->session = session;
- chan->id = session->free_chan_id++;
- /*
- * Note: the channel creation op already writes into the packet
- * headers. Therefore the "chan" information used as input
- * should be already accessible.
- */
- transport->ops.channel_create("[lttng]", chan, buf_addr,
- subbuf_size, num_subbuf, switch_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);
- return chan;
-
-create_error:
- free(chan);
-nomem:
-notransport:
-active:
- return NULL;
-}
-
-/*
- * Only used internally at session destruction.
- */
-static
-void _ltt_channel_destroy(struct ltt_channel *chan)
-{
- chan->ops->channel_destroy(chan);
- cds_list_del(&chan->list);
- lttng_destroy_context(chan->ctx);
- free(chan);
-}
-
-/*
- * Supports event creation while tracing session is active.
- */
-struct ltt_event *ltt_event_create(struct ltt_channel *chan,
- struct lttng_ust_event *event_param,
- void *filter)
-{
- struct ltt_event *event;
- int ret;
-
- 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 (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;
- /*
- * 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. */
- cmm_smp_wmb();
- switch (event_param->instrumentation) {
- case LTTNG_UST_TRACEPOINT:
- event->desc = ltt_event_get(event_param->name);
- 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);
- }
- 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);
- return event;
-
-statedump_error:
- 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:
- return NULL;
-}
-
-/*
- * Only used internally at session destruction.
- */
-int _ltt_event_unregister(struct ltt_event *event)
-{
- int ret = -EINVAL;
-
- switch (event->instrumentation) {
- case LTTNG_UST_TRACEPOINT:
- 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);
- }
- return ret;
-}
-
-/*
- * Only used internally at session destruction.
- */
-static
-void _ltt_event_destroy(struct ltt_event *event)
-{
- switch (event->instrumentation) {
- case LTTNG_UST_TRACEPOINT:
- if (event->desc) {
- ltt_event_put(event->desc);
- }
- break;
- default:
- WARN_ON_ONCE(1);
- }
- cds_list_del(&event->list);
- lttng_destroy_context(event->ctx);
- free(event);
-}
-
-/*
- * We have exclusive access to our metadata buffer (protected by the
- * 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 lttng_ust_lib_ring_buffer_ctx ctx;
- struct ltt_channel *chan = session->metadata;
- char *str = NULL;
- int ret = 0, waitret;
- size_t len, reserve_len, pos;
- va_list ap;
-
- WARN_ON_ONCE(!CMM_ACCESS_ONCE(session->active));
-
- va_start(ap, fmt);
- ret = vasprintf(&str, fmt, ap);
- va_end(ap);
- if (ret < 0)
- return -ENOMEM;
-
- len = strlen(str);
- pos = 0;
-
- for (pos = 0; pos < len; pos += reserve_len) {
- reserve_len = min_t(size_t,
- chan->ops->packet_avail_size(chan->chan, chan->handle),
- len - pos);
- lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
- sizeof(char), -1, chan->handle);
- /*
- * We don't care about metadata buffer's records lost
- * count, because we always retry here. Report error if
- * we need to bail out after timeout or being
- * interrupted.
- */
- waitret = wait_cond_interruptible_timeout(
- ({
- ret = chan->ops->event_reserve(&ctx, 0);
- ret != -ENOBUFS || !ret;
- }),
- LTTNG_METADATA_TIMEOUT_MSEC);
- if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) {
- DBG("LTTng: Failure to write metadata to buffers (%s)\n",
- waitret == -EINTR ? "interrupted" :
- (ret == -ENOBUFS ? "timeout" : "I/O error"));
- if (waitret == -EINTR)
- ret = waitret;
- goto end;
- }
- chan->ops->event_write(&ctx, &str[pos], reserve_len);
- chan->ops->event_commit(&ctx);
- }
-end:
- free(str);
- return ret;
-}
-
-static
-int _ltt_field_statedump(struct ltt_session *session,
- const struct lttng_event_field *field)
-{
- int ret = 0;
-
- 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",
- field->type.u.basic.integer.size,
- field->type.u.basic.integer.alignment,
- field->type.u.basic.integer.signedness,
- (field->type.u.basic.integer.encoding == lttng_encode_none)
- ? "none"
- : (field->type.u.basic.integer.encoding == lttng_encode_UTF8)
- ? "UTF8"
- : "ASCII",
- field->type.u.basic.integer.base,
-#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;" : "",
-#endif
- field->name);
- break;
- case atype_float:
- ret = lttng_metadata_printf(session,
- " 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,
-#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;" : "",
-#endif
- field->name);
- break;
- case atype_enum:
- ret = lttng_metadata_printf(session,
- " %s %s;\n",
- field->type.u.basic.enumeration.name,
- field->name);
- break;
- case atype_array:
- {
- const struct lttng_basic_type *elem_type;
-
- 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",
- elem_type->u.basic.integer.size,
- elem_type->u.basic.integer.alignment,
- elem_type->u.basic.integer.signedness,
- (elem_type->u.basic.integer.encoding == lttng_encode_none)
- ? "none"
- : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8)
- ? "UTF8"
- : "ASCII",
- elem_type->u.basic.integer.base,
-#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;" : "",
-#endif
- field->name, field->type.u.array.length);
- break;
- }
- case atype_sequence:
- {
- const struct lttng_basic_type *elem_type;
- const struct lttng_basic_type *length_type;
-
- elem_type = &field->type.u.sequence.elem_type;
- length_type = &field->type.u.sequence.length_type;
- ret = lttng_metadata_printf(session,
- " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n",
- length_type->u.basic.integer.size,
- (unsigned int) length_type->u.basic.integer.alignment,
- length_type->u.basic.integer.signedness,
- (length_type->u.basic.integer.encoding == lttng_encode_none)
- ? "none"
- : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8)
- ? "UTF8"
- : "ASCII"),
- length_type->u.basic.integer.base,
-#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;" : "",
-#endif
- field->name);
- if (ret)
- return ret;
-
- ret = lttng_metadata_printf(session,
- " 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,
- (elem_type->u.basic.integer.encoding == lttng_encode_none)
- ? "none"
- : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8)
- ? "UTF8"
- : "ASCII"),
- elem_type->u.basic.integer.base,
-#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;" : "",
-#endif
- field->name,
- field->name);
- break;
- }
-
- case atype_string:
- /* Default encoding is UTF8 */
- ret = lttng_metadata_printf(session,
- " string%s _%s;\n",
- field->type.u.basic.string.encoding == lttng_encode_ASCII ?
- " { encoding = ASCII; }" : "",
- field->name);
- break;
- default:
- WARN_ON_ONCE(1);
- return -EINVAL;
- }
- return ret;
-}
-
-static
-int _ltt_context_metadata_statedump(struct ltt_session *session,
- struct lttng_ctx *ctx)
-{
- int ret = 0;
- int i;
-
- if (!ctx)
- return 0;
- for (i = 0; i < ctx->nr_fields; i++) {
- const struct lttng_ctx_field *field = &ctx->fields[i];
-
- ret = _ltt_field_statedump(session, &field->event_field);
- if (ret)
- return ret;
- }
- return ret;
-}
-
-static
-int _ltt_fields_metadata_statedump(struct ltt_session *session,
- struct ltt_event *event)
-{
- const struct lttng_event_desc *desc = event->desc;
- int ret = 0;
- int i;
-
- for (i = 0; i < desc->nr_fields; i++) {
- const struct lttng_event_field *field = &desc->fields[i];
-
- ret = _ltt_field_statedump(session, field);
- if (ret)
- return ret;
- }
- return ret;
-}
-
-static
-int _ltt_event_metadata_statedump(struct ltt_session *session,
- struct ltt_channel *chan,
- struct ltt_event *event)
-{
- int ret = 0;
-
- if (event->metadata_dumped || !CMM_ACCESS_ONCE(session->active))
- 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"
- " name = %s;\n"
- " id = %u;\n"
- " stream_id = %u;\n",
- event->desc->name,
- event->id,
- event->chan->id);
- if (ret)
- goto end;
-
- if (event->ctx) {
- ret = lttng_metadata_printf(session,
- " context := struct {\n");
- if (ret)
- goto end;
- }
- ret = _ltt_context_metadata_statedump(session, event->ctx);
- if (ret)
- goto end;
- if (event->ctx) {
- ret = lttng_metadata_printf(session,
- " };\n");
- if (ret)
- goto end;
- }
-
- ret = lttng_metadata_printf(session,
- " fields := struct {\n"
- );
- if (ret)
- goto end;
-
- ret = _ltt_fields_metadata_statedump(session, event);
- if (ret)
- goto end;
-
- /*
- * LTTng space reservation can only reserve multiples of the
- * byte size.
- */
- ret = lttng_metadata_printf(session,
- " };\n"
- "};\n\n");
- if (ret)
- goto end;
-
- event->metadata_dumped = 1;
-end:
- return ret;
-
-}
-
-static
-int _ltt_channel_metadata_statedump(struct ltt_session *session,
- struct ltt_channel *chan)
-{
- int ret = 0;
-
- if (chan->metadata_dumped || !CMM_ACCESS_ONCE(session->active))
- return 0;
- if (chan == session->metadata)
- return 0;
-
- WARN_ON_ONCE(!chan->header_type);
- ret = lttng_metadata_printf(session,
- "stream {\n"
- " id = %u;\n"
- " event.header := %s;\n"
- " packet.context := struct packet_context;\n",
- chan->id,
- chan->header_type == 1 ? "struct event_header_compact" :
- "struct event_header_large");
- if (ret)
- goto end;
-
- if (chan->ctx) {
- ret = lttng_metadata_printf(session,
- " event.context := struct {\n");
- if (ret)
- goto end;
- }
- ret = _ltt_context_metadata_statedump(session, chan->ctx);
- if (ret)
- goto end;
- if (chan->ctx) {
- ret = lttng_metadata_printf(session,
- " };\n");
- if (ret)
- goto end;
- }
-
- ret = lttng_metadata_printf(session,
- "};\n\n");
-
- chan->metadata_dumped = 1;
-end:
- return ret;
-}
-
-static
-int _ltt_stream_packet_context_declare(struct ltt_session *session)
-{
- return lttng_metadata_printf(session,
- "struct packet_context {\n"
- " uint64_t timestamp_begin;\n"
- " uint64_t timestamp_end;\n"
- " uint32_t events_discarded;\n"
- " uint32_t content_size;\n"
- " uint32_t packet_size;\n"
- " uint32_t cpu_id;\n"
- "};\n\n"
- );
-}
-
-/*
- * Compact header:
- * id: range: 0 - 30.
- * id 31 is reserved to indicate an extended header.
- *
- * Large header:
- * id: range: 0 - 65534.
- * id 65535 is reserved to indicate an extended header.
- */
-static
-int _ltt_event_header_declare(struct ltt_session *session)
-{
- return lttng_metadata_printf(session,
- "struct event_header_compact {\n"
- " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
- " variant <id> {\n"
- " struct {\n"
- " uint27_t timestamp;\n"
- " } compact;\n"
- " struct {\n"
- " uint32_t id;\n"
- " uint64_t timestamp;\n"
- " } extended;\n"
- " } v;\n"
- "} align(%u);\n"
- "\n"
- "struct event_header_large {\n"
- " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
- " variant <id> {\n"
- " struct {\n"
- " uint32_t timestamp;\n"
- " } compact;\n"
- " struct {\n"
- " uint32_t id;\n"
- " uint64_t timestamp;\n"
- " } extended;\n"
- " } v;\n"
- "} align(%u);\n\n",
- lttng_alignof(uint32_t) * CHAR_BIT,
- lttng_alignof(uint16_t) * CHAR_BIT
- );
-}
-
-/*
- * Output metadata into this session's metadata buffers.
- */
-static
-int _ltt_session_metadata_statedump(struct ltt_session *session)
-{
- unsigned char *uuid_c = session->uuid;
- char uuid_s[37];
- struct ltt_channel *chan;
- struct ltt_event *event;
- int ret = 0;
-
- if (!CMM_ACCESS_ONCE(session->active))
- return 0;
- if (session->metadata_dumped)
- goto skip_session;
- if (!session->metadata) {
- DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n");
- return -EPERM;
- }
-
- snprintf(uuid_s, sizeof(uuid_s),
- "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
- uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
- uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
- uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
- uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
-
- ret = lttng_metadata_printf(session,
- "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
- "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
- "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
- "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
- "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
- "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
- "\n"
- "trace {\n"
- " major = %u;\n"
- " minor = %u;\n"
- " uuid = \"%s\";\n"
- " byte_order = %s;\n"
- " packet.header := struct {\n"
- " uint32_t magic;\n"
- " uint8_t uuid[16];\n"
- " uint32_t stream_id;\n"
- " };\n"
- "};\n\n",
- lttng_alignof(uint8_t) * CHAR_BIT,
- lttng_alignof(uint16_t) * CHAR_BIT,
- lttng_alignof(uint32_t) * CHAR_BIT,
- lttng_alignof(uint64_t) * CHAR_BIT,
- CTF_VERSION_MAJOR,
- CTF_VERSION_MINOR,
- uuid_s,
-#if (BYTE_ORDER == BIG_ENDIAN)
- "be"
-#else
- "le"
-#endif
- );
- if (ret)
- goto end;
-
- ret = _ltt_stream_packet_context_declare(session);
- if (ret)
- goto end;
-
- ret = _ltt_event_header_declare(session);
- if (ret)
- goto end;
-
-skip_session:
- cds_list_for_each_entry(chan, &session->chan, list) {
- ret = _ltt_channel_metadata_statedump(session, chan);
- if (ret)
- goto end;
- }
-
- cds_list_for_each_entry(event, &session->events, list) {
- ret = _ltt_event_metadata_statedump(session, event->chan, event);
- if (ret)
- goto end;
- }
- session->metadata_dumped = 1;
-end:
- return ret;
-}
-
-/**
- * ltt_transport_register - LTT transport registration
- * @transport: transport structure
- *
- * Registers a transport which can be used as output to extract the data out of
- * LTTng. Called with ust_lock held.
- */
-void ltt_transport_register(struct ltt_transport *transport)
-{
- cds_list_add_tail(&transport->node, <t_transport_list);
-}
-
-/**
- * ltt_transport_unregister - LTT transport unregistration
- * @transport: transport structure
- * Called with ust_lock held.
- */
-void ltt_transport_unregister(struct ltt_transport *transport)
-{
- cds_list_del(&transport->node);
-}
-
-void lttng_ust_events_exit(void)
-{
- struct ltt_session *session, *tmpsession;
-
- cds_list_for_each_entry_safe(session, tmpsession, &sessions, list)
- ltt_session_destroy(session);
-}
projects / ust.git / blobdiff