+++ /dev/null
-/*
- * lttng-events.c
- *
- * Holds LTTng per-session event registry.
- *
- * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * 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; only
- * version 2.1 of the License.
- *
- * 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 page_alloc.h wrapper needs to be included before gfpflags.h because it
- * overrides a function with a define.
- */
-#include "wrapper/page_alloc.h"
-
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/jiffies.h>
-#include <linux/utsname.h>
-#include <linux/err.h>
-#include <linux/seq_file.h>
-#include <linux/file.h>
-#include <linux/anon_inodes.h>
-#include <wrapper/file.h>
-#include <linux/jhash.h>
-#include <linux/uaccess.h>
-#include <linux/vmalloc.h>
-
-#include <wrapper/uuid.h>
-#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_all() */
-#include <wrapper/random.h>
-#include <wrapper/tracepoint.h>
-#include <wrapper/list.h>
-#include <wrapper/types.h>
-#include <lttng-kernel-version.h>
-#include <lttng-events.h>
-#include <lttng-tracer.h>
-#include <lttng-abi-old.h>
-#include <lttng-endian.h>
-#include <lttng-string-utils.h>
-#include <wrapper/vzalloc.h>
-#include <wrapper/ringbuffer/backend.h>
-#include <wrapper/ringbuffer/frontend.h>
-
-#define METADATA_CACHE_DEFAULT_SIZE 4096
-
-static LIST_HEAD(sessions);
-static LIST_HEAD(lttng_transport_list);
-/*
- * Protect the sessions and metadata caches.
- */
-static DEFINE_MUTEX(sessions_mutex);
-static struct kmem_cache *event_cache;
-
-static void lttng_session_lazy_sync_enablers(struct lttng_session *session);
-static void lttng_session_sync_enablers(struct lttng_session *session);
-static void lttng_enabler_destroy(struct lttng_enabler *enabler);
-
-static void _lttng_event_destroy(struct lttng_event *event);
-static void _lttng_channel_destroy(struct lttng_channel *chan);
-static int _lttng_event_unregister(struct lttng_event *event);
-static
-int _lttng_event_metadata_statedump(struct lttng_session *session,
- struct lttng_channel *chan,
- struct lttng_event *event);
-static
-int _lttng_session_metadata_statedump(struct lttng_session *session);
-static
-void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
-static
-int _lttng_field_statedump(struct lttng_session *session,
- const struct lttng_event_field *field,
- size_t nesting);
-
-void synchronize_trace(void)
-{
- synchronize_sched();
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0))
-#ifdef CONFIG_PREEMPT_RT_FULL
- synchronize_rcu();
-#endif
-#else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
-#ifdef CONFIG_PREEMPT_RT
- synchronize_rcu();
-#endif
-#endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
-}
-
-void lttng_lock_sessions(void)
-{
- mutex_lock(&sessions_mutex);
-}
-
-void lttng_unlock_sessions(void)
-{
- mutex_unlock(&sessions_mutex);
-}
-
-/*
- * Called with sessions lock held.
- */
-int lttng_session_active(void)
-{
- struct lttng_session *iter;
-
- list_for_each_entry(iter, &sessions, list) {
- if (iter->active)
- return 1;
- }
- return 0;
-}
-
-struct lttng_session *lttng_session_create(void)
-{
- struct lttng_session *session;
- struct lttng_metadata_cache *metadata_cache;
- int i;
-
- mutex_lock(&sessions_mutex);
- session = lttng_kvzalloc(sizeof(struct lttng_session), GFP_KERNEL);
- if (!session)
- goto err;
- INIT_LIST_HEAD(&session->chan);
- INIT_LIST_HEAD(&session->events);
- uuid_le_gen(&session->uuid);
-
- metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
- GFP_KERNEL);
- if (!metadata_cache)
- goto err_free_session;
- metadata_cache->data = lttng_vzalloc(METADATA_CACHE_DEFAULT_SIZE);
- if (!metadata_cache->data)
- goto err_free_cache;
- metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
- kref_init(&metadata_cache->refcount);
- mutex_init(&metadata_cache->lock);
- session->metadata_cache = metadata_cache;
- INIT_LIST_HEAD(&metadata_cache->metadata_stream);
- memcpy(&metadata_cache->uuid, &session->uuid,
- sizeof(metadata_cache->uuid));
- INIT_LIST_HEAD(&session->enablers_head);
- for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
- INIT_HLIST_HEAD(&session->events_ht.table[i]);
- list_add(&session->list, &sessions);
- mutex_unlock(&sessions_mutex);
- return session;
-
-err_free_cache:
- kfree(metadata_cache);
-err_free_session:
- lttng_kvfree(session);
-err:
- mutex_unlock(&sessions_mutex);
- return NULL;
-}
-
-void metadata_cache_destroy(struct kref *kref)
-{
- struct lttng_metadata_cache *cache =
- container_of(kref, struct lttng_metadata_cache, refcount);
- vfree(cache->data);
- kfree(cache);
-}
-
-void lttng_session_destroy(struct lttng_session *session)
-{
- struct lttng_channel *chan, *tmpchan;
- struct lttng_event *event, *tmpevent;
- struct lttng_metadata_stream *metadata_stream;
- struct lttng_enabler *enabler, *tmpenabler;
- int ret;
-
- mutex_lock(&sessions_mutex);
- WRITE_ONCE(session->active, 0);
- list_for_each_entry(chan, &session->chan, list) {
- ret = lttng_syscalls_unregister(chan);
- WARN_ON(ret);
- }
- list_for_each_entry(event, &session->events, list) {
- ret = _lttng_event_unregister(event);
- WARN_ON(ret);
- }
- synchronize_trace(); /* Wait for in-flight events to complete */
- list_for_each_entry_safe(enabler, tmpenabler,
- &session->enablers_head, node)
- lttng_enabler_destroy(enabler);
- list_for_each_entry_safe(event, tmpevent, &session->events, list)
- _lttng_event_destroy(event);
- list_for_each_entry_safe(chan, tmpchan, &session->chan, list) {
- BUG_ON(chan->channel_type == METADATA_CHANNEL);
- _lttng_channel_destroy(chan);
- }
- list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list)
- _lttng_metadata_channel_hangup(metadata_stream);
- if (session->pid_tracker)
- lttng_pid_tracker_destroy(session->pid_tracker);
- kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
- list_del(&session->list);
- mutex_unlock(&sessions_mutex);
- lttng_kvfree(session);
-}
-
-int lttng_session_statedump(struct lttng_session *session)
-{
- int ret;
-
- mutex_lock(&sessions_mutex);
- ret = lttng_statedump_start(session);
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_session_enable(struct lttng_session *session)
-{
- int ret = 0;
- struct lttng_channel *chan;
-
- mutex_lock(&sessions_mutex);
- if (session->active) {
- ret = -EBUSY;
- goto end;
- }
-
- /* Set transient enabler state to "enabled" */
- session->tstate = 1;
-
- /*
- * Snapshot the number of events per channel to know the type of header
- * we need to use.
- */
- 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 */
- }
-
- /* We need to sync enablers with session before activation. */
- lttng_session_sync_enablers(session);
-
- /* Clear each stream's quiescent state. */
- list_for_each_entry(chan, &session->chan, list) {
- if (chan->channel_type != METADATA_CHANNEL)
- lib_ring_buffer_clear_quiescent_channel(chan->chan);
- }
-
- WRITE_ONCE(session->active, 1);
- WRITE_ONCE(session->been_active, 1);
- ret = _lttng_session_metadata_statedump(session);
- if (ret) {
- WRITE_ONCE(session->active, 0);
- goto end;
- }
- ret = lttng_statedump_start(session);
- if (ret)
- WRITE_ONCE(session->active, 0);
-end:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_session_disable(struct lttng_session *session)
-{
- int ret = 0;
- struct lttng_channel *chan;
-
- mutex_lock(&sessions_mutex);
- if (!session->active) {
- ret = -EBUSY;
- goto end;
- }
- WRITE_ONCE(session->active, 0);
-
- /* Set transient enabler state to "disabled" */
- session->tstate = 0;
- lttng_session_sync_enablers(session);
-
- /* Set each stream's quiescent state. */
- list_for_each_entry(chan, &session->chan, list) {
- if (chan->channel_type != METADATA_CHANNEL)
- lib_ring_buffer_set_quiescent_channel(chan->chan);
- }
-end:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_session_metadata_regenerate(struct lttng_session *session)
-{
- int ret = 0;
- struct lttng_channel *chan;
- struct lttng_event *event;
- struct lttng_metadata_cache *cache = session->metadata_cache;
- struct lttng_metadata_stream *stream;
-
- mutex_lock(&sessions_mutex);
- if (!session->active) {
- ret = -EBUSY;
- goto end;
- }
-
- mutex_lock(&cache->lock);
- memset(cache->data, 0, cache->cache_alloc);
- cache->metadata_written = 0;
- cache->version++;
- list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) {
- stream->metadata_out = 0;
- stream->metadata_in = 0;
- }
- mutex_unlock(&cache->lock);
-
- session->metadata_dumped = 0;
- list_for_each_entry(chan, &session->chan, list) {
- chan->metadata_dumped = 0;
- }
-
- list_for_each_entry(event, &session->events, list) {
- event->metadata_dumped = 0;
- }
-
- ret = _lttng_session_metadata_statedump(session);
-
-end:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_channel_enable(struct lttng_channel *channel)
-{
- int ret = 0;
-
- mutex_lock(&sessions_mutex);
- if (channel->channel_type == METADATA_CHANNEL) {
- ret = -EPERM;
- goto end;
- }
- if (channel->enabled) {
- ret = -EEXIST;
- goto end;
- }
- /* Set transient enabler state to "enabled" */
- channel->tstate = 1;
- lttng_session_sync_enablers(channel->session);
- /* Set atomically the state to "enabled" */
- WRITE_ONCE(channel->enabled, 1);
-end:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_channel_disable(struct lttng_channel *channel)
-{
- int ret = 0;
-
- mutex_lock(&sessions_mutex);
- if (channel->channel_type == METADATA_CHANNEL) {
- ret = -EPERM;
- goto end;
- }
- if (!channel->enabled) {
- ret = -EEXIST;
- goto end;
- }
- /* Set atomically the state to "disabled" */
- WRITE_ONCE(channel->enabled, 0);
- /* Set transient enabler state to "enabled" */
- channel->tstate = 0;
- lttng_session_sync_enablers(channel->session);
-end:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_event_enable(struct lttng_event *event)
-{
- int ret = 0;
-
- mutex_lock(&sessions_mutex);
- if (event->chan->channel_type == METADATA_CHANNEL) {
- ret = -EPERM;
- goto end;
- }
- if (event->enabled) {
- ret = -EEXIST;
- goto end;
- }
- switch (event->instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- case LTTNG_KERNEL_SYSCALL:
- ret = -EINVAL;
- break;
- case LTTNG_KERNEL_KPROBE:
- case LTTNG_KERNEL_FUNCTION:
- case LTTNG_KERNEL_NOOP:
- WRITE_ONCE(event->enabled, 1);
- break;
- case LTTNG_KERNEL_KRETPROBE:
- ret = lttng_kretprobes_event_enable_state(event, 1);
- break;
- default:
- WARN_ON_ONCE(1);
- ret = -EINVAL;
- }
-end:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_event_disable(struct lttng_event *event)
-{
- int ret = 0;
-
- mutex_lock(&sessions_mutex);
- if (event->chan->channel_type == METADATA_CHANNEL) {
- ret = -EPERM;
- goto end;
- }
- if (!event->enabled) {
- ret = -EEXIST;
- goto end;
- }
- switch (event->instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- case LTTNG_KERNEL_SYSCALL:
- ret = -EINVAL;
- break;
- case LTTNG_KERNEL_KPROBE:
- case LTTNG_KERNEL_FUNCTION:
- case LTTNG_KERNEL_NOOP:
- WRITE_ONCE(event->enabled, 0);
- break;
- case LTTNG_KERNEL_KRETPROBE:
- ret = lttng_kretprobes_event_enable_state(event, 0);
- break;
- default:
- WARN_ON_ONCE(1);
- ret = -EINVAL;
- }
-end:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-static struct lttng_transport *lttng_transport_find(const char *name)
-{
- struct lttng_transport *transport;
-
- list_for_each_entry(transport, <tng_transport_list, node) {
- if (!strcmp(transport->name, name))
- return transport;
- }
- return NULL;
-}
-
-struct lttng_channel *lttng_channel_create(struct lttng_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,
- enum channel_type channel_type)
-{
- struct lttng_channel *chan;
- struct lttng_transport *transport = NULL;
-
- mutex_lock(&sessions_mutex);
- if (session->been_active && channel_type != METADATA_CHANNEL)
- goto active; /* Refuse to add channel to active session */
- transport = lttng_transport_find(transport_name);
- if (!transport) {
- printk(KERN_WARNING "LTTng transport %s not found\n",
- transport_name);
- goto notransport;
- }
- if (!try_module_get(transport->owner)) {
- printk(KERN_WARNING "LTT : Can't lock transport module.\n");
- goto notransport;
- }
- chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL);
- if (!chan)
- goto nomem;
- chan->session = session;
- chan->id = session->free_chan_id++;
- chan->ops = &transport->ops;
- /*
- * Note: the channel creation op already writes into the packet
- * headers. Therefore the "chan" information used as input
- * should be already accessible.
- */
- chan->chan = transport->ops.channel_create(transport_name,
- chan, buf_addr, subbuf_size, num_subbuf,
- switch_timer_interval, read_timer_interval);
- if (!chan->chan)
- goto create_error;
- chan->tstate = 1;
- chan->enabled = 1;
- chan->transport = transport;
- chan->channel_type = channel_type;
- list_add(&chan->list, &session->chan);
- mutex_unlock(&sessions_mutex);
- return chan;
-
-create_error:
- kfree(chan);
-nomem:
- if (transport)
- module_put(transport->owner);
-notransport:
-active:
- mutex_unlock(&sessions_mutex);
- return NULL;
-}
-
-/*
- * Only used internally at session destruction for per-cpu channels, and
- * when metadata channel is released.
- * Needs to be called with sessions mutex held.
- */
-static
-void _lttng_channel_destroy(struct lttng_channel *chan)
-{
- chan->ops->channel_destroy(chan->chan);
- module_put(chan->transport->owner);
- list_del(&chan->list);
- lttng_destroy_context(chan->ctx);
- kfree(chan);
-}
-
-void lttng_metadata_channel_destroy(struct lttng_channel *chan)
-{
- BUG_ON(chan->channel_type != METADATA_CHANNEL);
-
- /* Protect the metadata cache with the sessions_mutex. */
- mutex_lock(&sessions_mutex);
- _lttng_channel_destroy(chan);
- mutex_unlock(&sessions_mutex);
-}
-EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
-
-static
-void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
-{
- stream->finalized = 1;
- wake_up_interruptible(&stream->read_wait);
-}
-
-/*
- * Supports event creation while tracing session is active.
- * Needs to be called with sessions mutex held.
- */
-struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
- struct lttng_kernel_event *event_param,
- void *filter,
- const struct lttng_event_desc *event_desc,
- enum lttng_kernel_instrumentation itype)
-{
- struct lttng_session *session = chan->session;
- struct lttng_event *event;
- const char *event_name;
- struct hlist_head *head;
- size_t name_len;
- uint32_t hash;
- int ret;
-
- if (chan->free_event_id == -1U) {
- ret = -EMFILE;
- goto full;
- }
-
- switch (itype) {
- case LTTNG_KERNEL_TRACEPOINT:
- event_name = event_desc->name;
- break;
- case LTTNG_KERNEL_KPROBE:
- case LTTNG_KERNEL_KRETPROBE:
- case LTTNG_KERNEL_FUNCTION:
- case LTTNG_KERNEL_NOOP:
- case LTTNG_KERNEL_SYSCALL:
- event_name = event_param->name;
- break;
- default:
- WARN_ON_ONCE(1);
- ret = -EINVAL;
- goto type_error;
- }
- name_len = strlen(event_name);
- hash = jhash(event_name, name_len, 0);
- head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
- lttng_hlist_for_each_entry(event, head, hlist) {
- WARN_ON_ONCE(!event->desc);
- if (!strncmp(event->desc->name, event_name,
- LTTNG_KERNEL_SYM_NAME_LEN - 1)
- && chan == event->chan) {
- ret = -EEXIST;
- goto exist;
- }
- }
-
- event = kmem_cache_zalloc(event_cache, GFP_KERNEL);
- if (!event) {
- ret = -ENOMEM;
- goto cache_error;
- }
- event->chan = chan;
- event->filter = filter;
- event->id = chan->free_event_id++;
- event->instrumentation = itype;
- event->evtype = LTTNG_TYPE_EVENT;
- INIT_LIST_HEAD(&event->bytecode_runtime_head);
- INIT_LIST_HEAD(&event->enablers_ref_head);
-
- switch (itype) {
- case LTTNG_KERNEL_TRACEPOINT:
- /* Event will be enabled by enabler sync. */
- event->enabled = 0;
- event->registered = 0;
- event->desc = lttng_event_get(event_name);
- if (!event->desc) {
- ret = -ENOENT;
- goto register_error;
- }
- /* Populate lttng_event structure before event registration. */
- smp_wmb();
- break;
- case LTTNG_KERNEL_KPROBE:
- /*
- * Needs to be explicitly enabled after creation, since
- * we may want to apply filters.
- */
- event->enabled = 0;
- event->registered = 1;
- /*
- * Populate lttng_event structure before event
- * registration.
- */
- smp_wmb();
- ret = lttng_kprobes_register(event_name,
- event_param->u.kprobe.symbol_name,
- event_param->u.kprobe.offset,
- event_param->u.kprobe.addr,
- event);
- if (ret) {
- ret = -EINVAL;
- goto register_error;
- }
- ret = try_module_get(event->desc->owner);
- WARN_ON_ONCE(!ret);
- break;
- case LTTNG_KERNEL_KRETPROBE:
- {
- struct lttng_event *event_return;
-
- /* kretprobe defines 2 events */
- /*
- * Needs to be explicitly enabled after creation, since
- * we may want to apply filters.
- */
- event->enabled = 0;
- event->registered = 1;
- event_return =
- kmem_cache_zalloc(event_cache, GFP_KERNEL);
- if (!event_return) {
- ret = -ENOMEM;
- goto register_error;
- }
- event_return->chan = chan;
- event_return->filter = filter;
- event_return->id = chan->free_event_id++;
- event_return->enabled = 0;
- event_return->registered = 1;
- event_return->instrumentation = itype;
- /*
- * Populate lttng_event structure before kretprobe registration.
- */
- smp_wmb();
- ret = lttng_kretprobes_register(event_name,
- event_param->u.kretprobe.symbol_name,
- event_param->u.kretprobe.offset,
- event_param->u.kretprobe.addr,
- event, event_return);
- if (ret) {
- kmem_cache_free(event_cache, event_return);
- ret = -EINVAL;
- goto register_error;
- }
- /* Take 2 refs on the module: one per event. */
- ret = try_module_get(event->desc->owner);
- WARN_ON_ONCE(!ret);
- ret = try_module_get(event->desc->owner);
- WARN_ON_ONCE(!ret);
- ret = _lttng_event_metadata_statedump(chan->session, chan,
- event_return);
- WARN_ON_ONCE(ret > 0);
- if (ret) {
- kmem_cache_free(event_cache, event_return);
- module_put(event->desc->owner);
- module_put(event->desc->owner);
- goto statedump_error;
- }
- list_add(&event_return->list, &chan->session->events);
- break;
- }
- case LTTNG_KERNEL_FUNCTION:
- /*
- * Needs to be explicitly enabled after creation, since
- * we may want to apply filters.
- */
- event->enabled = 0;
- event->registered = 1;
- /*
- * Populate lttng_event structure before event
- * registration.
- */
- smp_wmb();
- ret = lttng_ftrace_register(event_name,
- event_param->u.ftrace.symbol_name,
- event);
- if (ret) {
- goto register_error;
- }
- ret = try_module_get(event->desc->owner);
- WARN_ON_ONCE(!ret);
- break;
- case LTTNG_KERNEL_NOOP:
- case LTTNG_KERNEL_SYSCALL:
- /*
- * Needs to be explicitly enabled after creation, since
- * we may want to apply filters.
- */
- event->enabled = 0;
- event->registered = 0;
- event->desc = event_desc;
- if (!event->desc) {
- ret = -EINVAL;
- goto register_error;
- }
- break;
- default:
- WARN_ON_ONCE(1);
- ret = -EINVAL;
- goto register_error;
- }
- ret = _lttng_event_metadata_statedump(chan->session, chan, event);
- WARN_ON_ONCE(ret > 0);
- if (ret) {
- goto statedump_error;
- }
- hlist_add_head(&event->hlist, head);
- list_add(&event->list, &chan->session->events);
- return event;
-
-statedump_error:
- /* If a statedump error occurs, events will not be readable. */
-register_error:
- kmem_cache_free(event_cache, event);
-cache_error:
-exist:
-type_error:
-full:
- return ERR_PTR(ret);
-}
-
-struct lttng_event *lttng_event_create(struct lttng_channel *chan,
- struct lttng_kernel_event *event_param,
- void *filter,
- const struct lttng_event_desc *event_desc,
- enum lttng_kernel_instrumentation itype)
-{
- struct lttng_event *event;
-
- mutex_lock(&sessions_mutex);
- event = _lttng_event_create(chan, event_param, filter, event_desc,
- itype);
- mutex_unlock(&sessions_mutex);
- return event;
-}
-
-/* Only used for tracepoints for now. */
-static
-void register_event(struct lttng_event *event)
-{
- const struct lttng_event_desc *desc;
- int ret = -EINVAL;
-
- if (event->registered)
- return;
-
- desc = event->desc;
- switch (event->instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- ret = lttng_wrapper_tracepoint_probe_register(desc->kname,
- desc->probe_callback,
- event);
- break;
- case LTTNG_KERNEL_SYSCALL:
- ret = lttng_syscall_filter_enable(event->chan,
- desc->name);
- break;
- case LTTNG_KERNEL_KPROBE:
- case LTTNG_KERNEL_KRETPROBE:
- case LTTNG_KERNEL_FUNCTION:
- case LTTNG_KERNEL_NOOP:
- ret = 0;
- break;
- default:
- WARN_ON_ONCE(1);
- }
- if (!ret)
- event->registered = 1;
-}
-
-/*
- * Only used internally at session destruction.
- */
-int _lttng_event_unregister(struct lttng_event *event)
-{
- const struct lttng_event_desc *desc;
- int ret = -EINVAL;
-
- if (!event->registered)
- return 0;
-
- desc = event->desc;
- switch (event->instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname,
- event->desc->probe_callback,
- event);
- break;
- case LTTNG_KERNEL_KPROBE:
- lttng_kprobes_unregister(event);
- ret = 0;
- break;
- case LTTNG_KERNEL_KRETPROBE:
- lttng_kretprobes_unregister(event);
- ret = 0;
- break;
- case LTTNG_KERNEL_FUNCTION:
- lttng_ftrace_unregister(event);
- ret = 0;
- break;
- case LTTNG_KERNEL_SYSCALL:
- ret = lttng_syscall_filter_disable(event->chan,
- desc->name);
- break;
- case LTTNG_KERNEL_NOOP:
- ret = 0;
- break;
- default:
- WARN_ON_ONCE(1);
- }
- if (!ret)
- event->registered = 0;
- return ret;
-}
-
-/*
- * Only used internally at session destruction.
- */
-static
-void _lttng_event_destroy(struct lttng_event *event)
-{
- switch (event->instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- lttng_event_put(event->desc);
- break;
- case LTTNG_KERNEL_KPROBE:
- module_put(event->desc->owner);
- lttng_kprobes_destroy_private(event);
- break;
- case LTTNG_KERNEL_KRETPROBE:
- module_put(event->desc->owner);
- lttng_kretprobes_destroy_private(event);
- break;
- case LTTNG_KERNEL_FUNCTION:
- module_put(event->desc->owner);
- lttng_ftrace_destroy_private(event);
- break;
- case LTTNG_KERNEL_NOOP:
- case LTTNG_KERNEL_SYSCALL:
- break;
- default:
- WARN_ON_ONCE(1);
- }
- list_del(&event->list);
- lttng_destroy_context(event->ctx);
- kmem_cache_free(event_cache, event);
-}
-
-int lttng_session_track_pid(struct lttng_session *session, int pid)
-{
- int ret;
-
- if (pid < -1)
- return -EINVAL;
- mutex_lock(&sessions_mutex);
- if (pid == -1) {
- /* track all pids: destroy tracker. */
- if (session->pid_tracker) {
- struct lttng_pid_tracker *lpf;
-
- lpf = session->pid_tracker;
- rcu_assign_pointer(session->pid_tracker, NULL);
- synchronize_trace();
- lttng_pid_tracker_destroy(lpf);
- }
- ret = 0;
- } else {
- if (!session->pid_tracker) {
- struct lttng_pid_tracker *lpf;
-
- lpf = lttng_pid_tracker_create();
- if (!lpf) {
- ret = -ENOMEM;
- goto unlock;
- }
- ret = lttng_pid_tracker_add(lpf, pid);
- rcu_assign_pointer(session->pid_tracker, lpf);
- } else {
- ret = lttng_pid_tracker_add(session->pid_tracker, pid);
- }
- }
-unlock:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-int lttng_session_untrack_pid(struct lttng_session *session, int pid)
-{
- int ret;
-
- if (pid < -1)
- return -EINVAL;
- mutex_lock(&sessions_mutex);
- if (pid == -1) {
- /* untrack all pids: replace by empty tracker. */
- struct lttng_pid_tracker *old_lpf = session->pid_tracker;
- struct lttng_pid_tracker *lpf;
-
- lpf = lttng_pid_tracker_create();
- if (!lpf) {
- ret = -ENOMEM;
- goto unlock;
- }
- rcu_assign_pointer(session->pid_tracker, lpf);
- synchronize_trace();
- if (old_lpf)
- lttng_pid_tracker_destroy(old_lpf);
- ret = 0;
- } else {
- if (!session->pid_tracker) {
- ret = -ENOENT;
- goto unlock;
- }
- ret = lttng_pid_tracker_del(session->pid_tracker, pid);
- }
-unlock:
- mutex_unlock(&sessions_mutex);
- return ret;
-}
-
-static
-void *pid_list_start(struct seq_file *m, loff_t *pos)
-{
- struct lttng_session *session = m->private;
- struct lttng_pid_tracker *lpf;
- struct lttng_pid_hash_node *e;
- int iter = 0, i;
-
- mutex_lock(&sessions_mutex);
- lpf = session->pid_tracker;
- if (lpf) {
- for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) {
- struct hlist_head *head = &lpf->pid_hash[i];
-
- lttng_hlist_for_each_entry(e, head, hlist) {
- if (iter++ >= *pos)
- return e;
- }
- }
- } else {
- /* PID tracker disabled. */
- if (iter >= *pos && iter == 0) {
- return session; /* empty tracker */
- }
- iter++;
- }
- /* End of list */
- return NULL;
-}
-
-/* Called with sessions_mutex held. */
-static
-void *pid_list_next(struct seq_file *m, void *p, loff_t *ppos)
-{
- struct lttng_session *session = m->private;
- struct lttng_pid_tracker *lpf;
- struct lttng_pid_hash_node *e;
- int iter = 0, i;
-
- (*ppos)++;
- lpf = session->pid_tracker;
- if (lpf) {
- for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) {
- struct hlist_head *head = &lpf->pid_hash[i];
-
- lttng_hlist_for_each_entry(e, head, hlist) {
- if (iter++ >= *ppos)
- return e;
- }
- }
- } else {
- /* PID tracker disabled. */
- if (iter >= *ppos && iter == 0)
- return session; /* empty tracker */
- iter++;
- }
-
- /* End of list */
- return NULL;
-}
-
-static
-void pid_list_stop(struct seq_file *m, void *p)
-{
- mutex_unlock(&sessions_mutex);
-}
-
-static
-int pid_list_show(struct seq_file *m, void *p)
-{
- int pid;
-
- if (p == m->private) {
- /* Tracker disabled. */
- pid = -1;
- } else {
- const struct lttng_pid_hash_node *e = p;
-
- pid = lttng_pid_tracker_get_node_pid(e);
- }
- seq_printf(m, "process { pid = %d; };\n", pid);
- return 0;
-}
-
-static
-const struct seq_operations lttng_tracker_pids_list_seq_ops = {
- .start = pid_list_start,
- .next = pid_list_next,
- .stop = pid_list_stop,
- .show = pid_list_show,
-};
-
-static
-int lttng_tracker_pids_list_open(struct inode *inode, struct file *file)
-{
- return seq_open(file, <tng_tracker_pids_list_seq_ops);
-}
-
-static
-int lttng_tracker_pids_list_release(struct inode *inode, struct file *file)
-{
- struct seq_file *m = file->private_data;
- struct lttng_session *session = m->private;
- int ret;
-
- WARN_ON_ONCE(!session);
- ret = seq_release(inode, file);
- if (!ret && session)
- fput(session->file);
- return ret;
-}
-
-const struct file_operations lttng_tracker_pids_list_fops = {
- .owner = THIS_MODULE,
- .open = lttng_tracker_pids_list_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = lttng_tracker_pids_list_release,
-};
-
-int lttng_session_list_tracker_pids(struct lttng_session *session)
-{
- struct file *tracker_pids_list_file;
- struct seq_file *m;
- int file_fd, ret;
-
- file_fd = lttng_get_unused_fd();
- if (file_fd < 0) {
- ret = file_fd;
- goto fd_error;
- }
-
- tracker_pids_list_file = anon_inode_getfile("[lttng_tracker_pids_list]",
- <tng_tracker_pids_list_fops,
- NULL, O_RDWR);
- if (IS_ERR(tracker_pids_list_file)) {
- ret = PTR_ERR(tracker_pids_list_file);
- goto file_error;
- }
- if (atomic_long_add_unless(&session->file->f_count,
- 1, INT_MAX) == INT_MAX) {
- goto refcount_error;
- }
- ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file);
- if (ret < 0)
- goto open_error;
- m = tracker_pids_list_file->private_data;
- m->private = session;
- fd_install(file_fd, tracker_pids_list_file);
-
- return file_fd;
-
-open_error:
- atomic_long_dec(&session->file->f_count);
-refcount_error:
- fput(tracker_pids_list_file);
-file_error:
- put_unused_fd(file_fd);
-fd_error:
- return ret;
-}
-
-/*
- * Enabler management.
- */
-static
-int lttng_match_enabler_star_glob(const char *desc_name,
- const char *pattern)
-{
- if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
- desc_name, LTTNG_SIZE_MAX))
- return 0;
- return 1;
-}
-
-static
-int lttng_match_enabler_name(const char *desc_name,
- const char *name)
-{
- if (strcmp(desc_name, name))
- return 0;
- return 1;
-}
-
-static
-int lttng_desc_match_enabler(const struct lttng_event_desc *desc,
- struct lttng_enabler *enabler)
-{
- const char *desc_name, *enabler_name;
-
- enabler_name = enabler->event_param.name;
- switch (enabler->event_param.instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- desc_name = desc->name;
- break;
- case LTTNG_KERNEL_SYSCALL:
- desc_name = desc->name;
- if (!strncmp(desc_name, "compat_", strlen("compat_")))
- desc_name += strlen("compat_");
- if (!strncmp(desc_name, "syscall_exit_",
- strlen("syscall_exit_"))) {
- desc_name += strlen("syscall_exit_");
- } else if (!strncmp(desc_name, "syscall_entry_",
- strlen("syscall_entry_"))) {
- desc_name += strlen("syscall_entry_");
- } else {
- WARN_ON_ONCE(1);
- return -EINVAL;
- }
- break;
- default:
- WARN_ON_ONCE(1);
- return -EINVAL;
- }
- switch (enabler->type) {
- case LTTNG_ENABLER_STAR_GLOB:
- return lttng_match_enabler_star_glob(desc_name, enabler_name);
- case LTTNG_ENABLER_NAME:
- return lttng_match_enabler_name(desc_name, enabler_name);
- default:
- return -EINVAL;
- }
-}
-
-static
-int lttng_event_match_enabler(struct lttng_event *event,
- struct lttng_enabler *enabler)
-{
- if (enabler->event_param.instrumentation != event->instrumentation)
- return 0;
- if (lttng_desc_match_enabler(event->desc, enabler)
- && event->chan == enabler->chan)
- return 1;
- else
- return 0;
-}
-
-static
-struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event,
- struct lttng_enabler *enabler)
-{
- struct lttng_enabler_ref *enabler_ref;
-
- list_for_each_entry(enabler_ref,
- &event->enablers_ref_head, node) {
- if (enabler_ref->ref == enabler)
- return enabler_ref;
- }
- return NULL;
-}
-
-static
-void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler)
-{
- struct lttng_session *session = enabler->chan->session;
- struct lttng_probe_desc *probe_desc;
- const struct lttng_event_desc *desc;
- int i;
- struct list_head *probe_list;
-
- probe_list = lttng_get_probe_list_head();
- /*
- * For each probe event, if we find that a probe event matches
- * our enabler, create an associated lttng_event if not
- * already present.
- */
- list_for_each_entry(probe_desc, probe_list, head) {
- for (i = 0; i < probe_desc->nr_events; i++) {
- int found = 0;
- struct hlist_head *head;
- const char *event_name;
- size_t name_len;
- uint32_t hash;
- struct lttng_event *event;
-
- desc = probe_desc->event_desc[i];
- if (!lttng_desc_match_enabler(desc, enabler))
- continue;
- event_name = desc->name;
- name_len = strlen(event_name);
-
- /*
- * Check if already created.
- */
- hash = jhash(event_name, name_len, 0);
- head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
- lttng_hlist_for_each_entry(event, head, hlist) {
- if (event->desc == desc
- && event->chan == enabler->chan)
- found = 1;
- }
- if (found)
- continue;
-
- /*
- * We need to create an event for this
- * event probe.
- */
- event = _lttng_event_create(enabler->chan,
- NULL, NULL, desc,
- LTTNG_KERNEL_TRACEPOINT);
- if (!event) {
- printk(KERN_INFO "Unable to create event %s\n",
- probe_desc->event_desc[i]->name);
- }
- }
- }
-}
-
-static
-void lttng_create_syscall_if_missing(struct lttng_enabler *enabler)
-{
- int ret;
-
- ret = lttng_syscalls_register(enabler->chan, NULL);
- WARN_ON_ONCE(ret);
-}
-
-/*
- * Create struct lttng_event if it is missing and present in the list of
- * tracepoint probes.
- * Should be called with sessions mutex held.
- */
-static
-void lttng_create_event_if_missing(struct lttng_enabler *enabler)
-{
- switch (enabler->event_param.instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- lttng_create_tracepoint_if_missing(enabler);
- break;
- case LTTNG_KERNEL_SYSCALL:
- lttng_create_syscall_if_missing(enabler);
- break;
- default:
- WARN_ON_ONCE(1);
- break;
- }
-}
-
-/*
- * Create events associated with an enabler (if not already present),
- * and add backward reference from the event to the enabler.
- * Should be called with sessions mutex held.
- */
-static
-int lttng_enabler_ref_events(struct lttng_enabler *enabler)
-{
- struct lttng_session *session = enabler->chan->session;
- struct lttng_event *event;
-
- /* First ensure that probe events are created for this enabler. */
- lttng_create_event_if_missing(enabler);
-
- /* For each event matching enabler in session event list. */
- list_for_each_entry(event, &session->events, list) {
- struct lttng_enabler_ref *enabler_ref;
-
- if (!lttng_event_match_enabler(event, enabler))
- continue;
- enabler_ref = lttng_event_enabler_ref(event, enabler);
- if (!enabler_ref) {
- /*
- * If no backward ref, create it.
- * Add backward ref from event to enabler.
- */
- enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
- if (!enabler_ref)
- return -ENOMEM;
- enabler_ref->ref = enabler;
- list_add(&enabler_ref->node,
- &event->enablers_ref_head);
- }
-
- /*
- * Link filter bytecodes if not linked yet.
- */
- lttng_enabler_event_link_bytecode(event, enabler);
-
- /* TODO: merge event context. */
- }
- return 0;
-}
-
-/*
- * Called at module load: connect the probe on all enablers matching
- * this event.
- * Called with sessions lock held.
- */
-int lttng_fix_pending_events(void)
-{
- struct lttng_session *session;
-
- list_for_each_entry(session, &sessions, list)
- lttng_session_lazy_sync_enablers(session);
- return 0;
-}
-
-struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
- struct lttng_kernel_event *event_param,
- struct lttng_channel *chan)
-{
- struct lttng_enabler *enabler;
-
- enabler = kzalloc(sizeof(*enabler), GFP_KERNEL);
- if (!enabler)
- return NULL;
- enabler->type = type;
- INIT_LIST_HEAD(&enabler->filter_bytecode_head);
- memcpy(&enabler->event_param, event_param,
- sizeof(enabler->event_param));
- enabler->chan = chan;
- /* ctx left NULL */
- enabler->enabled = 0;
- enabler->evtype = LTTNG_TYPE_ENABLER;
- mutex_lock(&sessions_mutex);
- list_add(&enabler->node, &enabler->chan->session->enablers_head);
- lttng_session_lazy_sync_enablers(enabler->chan->session);
- mutex_unlock(&sessions_mutex);
- return enabler;
-}
-
-int lttng_enabler_enable(struct lttng_enabler *enabler)
-{
- mutex_lock(&sessions_mutex);
- enabler->enabled = 1;
- lttng_session_lazy_sync_enablers(enabler->chan->session);
- mutex_unlock(&sessions_mutex);
- return 0;
-}
-
-int lttng_enabler_disable(struct lttng_enabler *enabler)
-{
- mutex_lock(&sessions_mutex);
- enabler->enabled = 0;
- lttng_session_lazy_sync_enablers(enabler->chan->session);
- mutex_unlock(&sessions_mutex);
- return 0;
-}
-
-int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
- struct lttng_kernel_filter_bytecode __user *bytecode)
-{
- struct lttng_filter_bytecode_node *bytecode_node;
- uint32_t bytecode_len;
- int ret;
-
- ret = get_user(bytecode_len, &bytecode->len);
- if (ret)
- return ret;
- bytecode_node = kzalloc(sizeof(*bytecode_node) + bytecode_len,
- GFP_KERNEL);
- if (!bytecode_node)
- return -ENOMEM;
- ret = copy_from_user(&bytecode_node->bc, bytecode,
- sizeof(*bytecode) + bytecode_len);
- if (ret)
- goto error_free;
- bytecode_node->enabler = enabler;
- /* Enforce length based on allocated size */
- bytecode_node->bc.len = bytecode_len;
- list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
- lttng_session_lazy_sync_enablers(enabler->chan->session);
- return 0;
-
-error_free:
- kfree(bytecode_node);
- return ret;
-}
-
-int lttng_enabler_attach_context(struct lttng_enabler *enabler,
- struct lttng_kernel_context *context_param)
-{
- return -ENOSYS;
-}
-
-static
-void lttng_enabler_destroy(struct lttng_enabler *enabler)
-{
- struct lttng_filter_bytecode_node *filter_node, *tmp_filter_node;
-
- /* Destroy filter bytecode */
- list_for_each_entry_safe(filter_node, tmp_filter_node,
- &enabler->filter_bytecode_head, node) {
- kfree(filter_node);
- }
-
- /* Destroy contexts */
- lttng_destroy_context(enabler->ctx);
-
- list_del(&enabler->node);
- kfree(enabler);
-}
-
-/*
- * lttng_session_sync_enablers should be called just before starting a
- * session.
- * Should be called with sessions mutex held.
- */
-static
-void lttng_session_sync_enablers(struct lttng_session *session)
-{
- struct lttng_enabler *enabler;
- struct lttng_event *event;
-
- list_for_each_entry(enabler, &session->enablers_head, node)
- lttng_enabler_ref_events(enabler);
- /*
- * For each event, if at least one of its enablers is enabled,
- * and its channel and session transient states are enabled, we
- * enable the event, else we disable it.
- */
- list_for_each_entry(event, &session->events, list) {
- struct lttng_enabler_ref *enabler_ref;
- struct lttng_bytecode_runtime *runtime;
- int enabled = 0, has_enablers_without_bytecode = 0;
-
- switch (event->instrumentation) {
- case LTTNG_KERNEL_TRACEPOINT:
- case LTTNG_KERNEL_SYSCALL:
- /* Enable events */
- list_for_each_entry(enabler_ref,
- &event->enablers_ref_head, node) {
- if (enabler_ref->ref->enabled) {
- enabled = 1;
- break;
- }
- }
- break;
- default:
- /* Not handled with lazy sync. */
- continue;
- }
- /*
- * Enabled state is based on union of enablers, with
- * intesection of session and channel transient enable
- * states.
- */
- enabled = enabled && session->tstate && event->chan->tstate;
-
- WRITE_ONCE(event->enabled, enabled);
- /*
- * Sync tracepoint registration with event enabled
- * state.
- */
- if (enabled) {
- register_event(event);
- } else {
- _lttng_event_unregister(event);
- }
-
- /* Check if has enablers without bytecode enabled */
- list_for_each_entry(enabler_ref,
- &event->enablers_ref_head, node) {
- if (enabler_ref->ref->enabled
- && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
- has_enablers_without_bytecode = 1;
- break;
- }
- }
- event->has_enablers_without_bytecode =
- has_enablers_without_bytecode;
-
- /* Enable filters */
- list_for_each_entry(runtime,
- &event->bytecode_runtime_head, node)
- lttng_filter_sync_state(runtime);
- }
-}
-
-/*
- * Apply enablers to session events, adding events to session if need
- * be. It is required after each modification applied to an active
- * session, and right before session "start".
- * "lazy" sync means we only sync if required.
- * Should be called with sessions mutex held.
- */
-static
-void lttng_session_lazy_sync_enablers(struct lttng_session *session)
-{
- /* We can skip if session is not active */
- if (!session->active)
- return;
- lttng_session_sync_enablers(session);
-}
-
-/*
- * Serialize at most one packet worth of metadata into a metadata
- * channel.
- * We grab the metadata cache mutex to get exclusive access to our metadata
- * buffer and to the metadata cache. Exclusive access to the metadata buffer
- * allows us to do racy operations such as looking for remaining space left in
- * packet and write, since mutual exclusion protects us from concurrent writes.
- * Mutual exclusion on the metadata cache allow us to read the cache content
- * without racing against reallocation of the cache by updates.
- * Returns the number of bytes written in the channel, 0 if no data
- * was written and a negative value on error.
- */
-int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
- struct channel *chan)
-{
- struct lib_ring_buffer_ctx ctx;
- int ret = 0;
- size_t len, reserve_len;
-
- /*
- * Ensure we support mutiple get_next / put sequences followed by
- * put_next. The metadata cache lock protects reading the metadata
- * cache. It can indeed be read concurrently by "get_next_subbuf" and
- * "flush" operations on the buffer invoked by different processes.
- * Moreover, since the metadata cache memory can be reallocated, we
- * need to have exclusive access against updates even though we only
- * read it.
- */
- mutex_lock(&stream->metadata_cache->lock);
- WARN_ON(stream->metadata_in < stream->metadata_out);
- if (stream->metadata_in != stream->metadata_out)
- goto end;
-
- /* Metadata regenerated, change the version. */
- if (stream->metadata_cache->version != stream->version)
- stream->version = stream->metadata_cache->version;
-
- len = stream->metadata_cache->metadata_written -
- stream->metadata_in;
- if (!len)
- goto end;
- reserve_len = min_t(size_t,
- stream->transport->ops.packet_avail_size(chan),
- len);
- lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len,
- sizeof(char), -1);
- /*
- * If reservation failed, return an error to the caller.
- */
- ret = stream->transport->ops.event_reserve(&ctx, 0);
- if (ret != 0) {
- printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
- goto end;
- }
- stream->transport->ops.event_write(&ctx,
- stream->metadata_cache->data + stream->metadata_in,
- reserve_len);
- stream->transport->ops.event_commit(&ctx);
- stream->metadata_in += reserve_len;
- ret = reserve_len;
-
-end:
- mutex_unlock(&stream->metadata_cache->lock);
- return ret;
-}
-
-/*
- * Write the metadata to the metadata cache.
- * Must be called with sessions_mutex held.
- * The metadata cache lock protects us from concurrent read access from
- * thread outputting metadata content to ring buffer.
- */
-int lttng_metadata_printf(struct lttng_session *session,
- const char *fmt, ...)
-{
- char *str;
- size_t len;
- va_list ap;
- struct lttng_metadata_stream *stream;
-
- WARN_ON_ONCE(!READ_ONCE(session->active));
-
- va_start(ap, fmt);
- str = kvasprintf(GFP_KERNEL, fmt, ap);
- va_end(ap);
- if (!str)
- return -ENOMEM;
-
- len = strlen(str);
- mutex_lock(&session->metadata_cache->lock);
- if (session->metadata_cache->metadata_written + len >
- session->metadata_cache->cache_alloc) {
- char *tmp_cache_realloc;
- unsigned int tmp_cache_alloc_size;
-
- tmp_cache_alloc_size = max_t(unsigned int,
- session->metadata_cache->cache_alloc + len,
- session->metadata_cache->cache_alloc << 1);
- tmp_cache_realloc = lttng_vzalloc(tmp_cache_alloc_size);
- if (!tmp_cache_realloc)
- goto err;
- if (session->metadata_cache->data) {
- memcpy(tmp_cache_realloc,
- session->metadata_cache->data,
- session->metadata_cache->cache_alloc);
- vfree(session->metadata_cache->data);
- }
-
- session->metadata_cache->cache_alloc = tmp_cache_alloc_size;
- session->metadata_cache->data = tmp_cache_realloc;
- }
- memcpy(session->metadata_cache->data +
- session->metadata_cache->metadata_written,
- str, len);
- session->metadata_cache->metadata_written += len;
- mutex_unlock(&session->metadata_cache->lock);
- kfree(str);
-
- list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list)
- wake_up_interruptible(&stream->read_wait);
-
- return 0;
-
-err:
- mutex_unlock(&session->metadata_cache->lock);
- kfree(str);
- return -ENOMEM;
-}
-
-static
-int print_tabs(struct lttng_session *session, size_t nesting)
-{
- size_t i;
-
- for (i = 0; i < nesting; i++) {
- int ret;
-
- ret = lttng_metadata_printf(session, " ");
- if (ret) {
- return ret;
- }
- }
- return 0;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_struct_type_statedump(struct lttng_session *session,
- const struct lttng_type *type,
- size_t nesting)
-{
- int ret;
- uint32_t i, nr_fields;
-
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "struct {\n");
- if (ret)
- return ret;
- nr_fields = type->u._struct.nr_fields;
- for (i = 0; i < nr_fields; i++) {
- const struct lttng_event_field *iter_field;
-
- iter_field = &type->u._struct.fields[i];
- ret = _lttng_field_statedump(session, iter_field, nesting + 1);
- if (ret)
- return ret;
- }
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "}");
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_struct_statedump(struct lttng_session *session,
- const struct lttng_event_field *field,
- size_t nesting)
-{
- int ret;
-
- ret = _lttng_struct_type_statedump(session,
- &field->type, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "_%s;\n",
- field->name);
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_variant_type_statedump(struct lttng_session *session,
- const struct lttng_type *type,
- size_t nesting)
-{
- int ret;
- uint32_t i, nr_choices;
-
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "variant <_%s> {\n",
- type->u.variant.tag_name);
- if (ret)
- return ret;
- nr_choices = type->u.variant.nr_choices;
- for (i = 0; i < nr_choices; i++) {
- const struct lttng_event_field *iter_field;
-
- iter_field = &type->u.variant.choices[i];
- ret = _lttng_field_statedump(session, iter_field, nesting + 1);
- if (ret)
- return ret;
- }
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "}");
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_variant_statedump(struct lttng_session *session,
- const struct lttng_event_field *field,
- size_t nesting)
-{
- int ret;
-
- ret = _lttng_variant_type_statedump(session,
- &field->type, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "_%s;\n",
- field->name);
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_array_compound_statedump(struct lttng_session *session,
- const struct lttng_event_field *field,
- size_t nesting)
-{
- int ret;
- const struct lttng_type *elem_type;
-
- /* Only array of structures and variants are currently supported. */
- elem_type = field->type.u.array_compound.elem_type;
- switch (elem_type->atype) {
- case atype_struct:
- ret = _lttng_struct_type_statedump(session, elem_type, nesting);
- if (ret)
- return ret;
- break;
- case atype_variant:
- ret = _lttng_variant_type_statedump(session, elem_type, nesting);
- if (ret)
- return ret;
- break;
- default:
- return -EINVAL;
- }
- ret = lttng_metadata_printf(session,
- " _%s[%u];\n",
- field->name,
- field->type.u.array_compound.length);
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_sequence_compound_statedump(struct lttng_session *session,
- const struct lttng_event_field *field,
- size_t nesting)
-{
- int ret;
- const char *length_name;
- const struct lttng_type *elem_type;
-
- length_name = field->type.u.sequence_compound.length_name;
-
- /* Only array of structures and variants are currently supported. */
- elem_type = field->type.u.sequence_compound.elem_type;
- switch (elem_type->atype) {
- case atype_struct:
- ret = _lttng_struct_type_statedump(session, elem_type, nesting);
- if (ret)
- return ret;
- break;
- case atype_variant:
- ret = _lttng_variant_type_statedump(session, elem_type, nesting);
- if (ret)
- return ret;
- break;
- default:
- return -EINVAL;
- }
- ret = lttng_metadata_printf(session,
- " _%s[ _%s ];\n",
- field->name,
- length_name);
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_enum_statedump(struct lttng_session *session,
- const struct lttng_event_field *field,
- size_t nesting)
-{
- const struct lttng_enum_desc *enum_desc;
- const struct lttng_integer_type *container_type;
- int ret;
- unsigned int i, nr_entries;
-
- enum_desc = field->type.u.basic.enumeration.desc;
- container_type = &field->type.u.basic.enumeration.container_type;
- nr_entries = enum_desc->nr_entries;
-
- ret = print_tabs(session, nesting);
- if (ret)
- goto end;
- ret = lttng_metadata_printf(session,
- "enum : integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } {\n",
- container_type->size,
- container_type->alignment,
- container_type->signedness,
- (container_type->encoding == lttng_encode_none)
- ? "none"
- : (container_type->encoding == lttng_encode_UTF8)
- ? "UTF8"
- : "ASCII",
- container_type->base,
-#if __BYTE_ORDER == __BIG_ENDIAN
- container_type->reverse_byte_order ? " byte_order = le;" : ""
-#else
- container_type->reverse_byte_order ? " byte_order = be;" : ""
-#endif
- );
- if (ret)
- goto end;
- /* Dump all entries */
- for (i = 0; i < nr_entries; i++) {
- const struct lttng_enum_entry *entry = &enum_desc->entries[i];
- int j, len;
-
- ret = print_tabs(session, nesting + 1);
- if (ret)
- goto end;
- ret = lttng_metadata_printf(session,
- "\"");
- if (ret)
- goto end;
- len = strlen(entry->string);
- /* Escape the character '"' */
- for (j = 0; j < len; j++) {
- char c = entry->string[j];
-
- switch (c) {
- case '"':
- ret = lttng_metadata_printf(session,
- "\\\"");
- break;
- case '\\':
- ret = lttng_metadata_printf(session,
- "\\\\");
- break;
- default:
- ret = lttng_metadata_printf(session,
- "%c", c);
- break;
- }
- if (ret)
- goto end;
- }
- ret = lttng_metadata_printf(session, "\"");
- if (ret)
- goto end;
-
- if (entry->options.is_auto) {
- ret = lttng_metadata_printf(session, ",\n");
- if (ret)
- goto end;
- } else {
- ret = lttng_metadata_printf(session,
- " = ");
- if (ret)
- goto end;
- if (entry->start.signedness)
- ret = lttng_metadata_printf(session,
- "%lld", (long long) entry->start.value);
- else
- ret = lttng_metadata_printf(session,
- "%llu", entry->start.value);
- if (ret)
- goto end;
- if (entry->start.signedness == entry->end.signedness &&
- entry->start.value
- == entry->end.value) {
- ret = lttng_metadata_printf(session,
- ",\n");
- } else {
- if (entry->end.signedness) {
- ret = lttng_metadata_printf(session,
- " ... %lld,\n",
- (long long) entry->end.value);
- } else {
- ret = lttng_metadata_printf(session,
- " ... %llu,\n",
- entry->end.value);
- }
- }
- if (ret)
- goto end;
- }
- }
- ret = print_tabs(session, nesting);
- if (ret)
- goto end;
- ret = lttng_metadata_printf(session, "} _%s;\n",
- field->name);
-end:
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_field_statedump(struct lttng_session *session,
- const struct lttng_event_field *field,
- size_t nesting)
-{
- int ret = 0;
-
- switch (field->type.atype) {
- case atype_integer:
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- 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_enum:
- ret = _lttng_enum_statedump(session, field, nesting);
- break;
- case atype_array:
- {
- const struct lttng_basic_type *elem_type;
-
- elem_type = &field->type.u.array.elem_type;
- if (field->type.u.array.elem_alignment) {
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "struct { } align(%u) _%s_padding;\n",
- field->type.u.array.elem_alignment * CHAR_BIT,
- field->name);
- if (ret)
- return ret;
- }
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- 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 = print_tabs(session, nesting);
- if (ret)
- return ret;
- 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;
-
- if (field->type.u.sequence.elem_alignment) {
- ret = print_tabs(session, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "struct { } align(%u) _%s_padding;\n",
- field->type.u.sequence.elem_alignment * CHAR_BIT,
- field->name);
- if (ret)
- return ret;
- }
- ret = print_tabs(session, nesting);
- 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 = print_tabs(session, nesting);
- if (ret)
- return ret;
- ret = lttng_metadata_printf(session,
- "string%s _%s;\n",
- field->type.u.basic.string.encoding == lttng_encode_ASCII ?
- " { encoding = ASCII; }" : "",
- field->name);
- break;
- case atype_struct:
- ret = _lttng_struct_statedump(session, field, nesting);
- break;
- case atype_array_compound:
- ret = _lttng_array_compound_statedump(session, field, nesting);
- break;
- case atype_sequence_compound:
- ret = _lttng_sequence_compound_statedump(session, field, nesting);
- break;
- case atype_variant:
- ret = _lttng_variant_statedump(session, field, nesting);
- break;
-
- default:
- WARN_ON_ONCE(1);
- return -EINVAL;
- }
- return ret;
-}
-
-static
-int _lttng_context_metadata_statedump(struct lttng_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 = _lttng_field_statedump(session, &field->event_field, 2);
- if (ret)
- return ret;
- }
- return ret;
-}
-
-static
-int _lttng_fields_metadata_statedump(struct lttng_session *session,
- struct lttng_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 = _lttng_field_statedump(session, field, 2);
- if (ret)
- return ret;
- }
- return ret;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_event_metadata_statedump(struct lttng_session *session,
- struct lttng_channel *chan,
- struct lttng_event *event)
-{
- int ret = 0;
-
- if (event->metadata_dumped || !READ_ONCE(session->active))
- return 0;
- if (chan->channel_type == METADATA_CHANNEL)
- 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 = _lttng_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 = _lttng_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;
-
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_channel_metadata_statedump(struct lttng_session *session,
- struct lttng_channel *chan)
-{
- int ret = 0;
-
- if (chan->metadata_dumped || !READ_ONCE(session->active))
- return 0;
-
- if (chan->channel_type == METADATA_CHANNEL)
- 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 = _lttng_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;
-}
-
-/*
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_stream_packet_context_declare(struct lttng_session *session)
-{
- return lttng_metadata_printf(session,
- "struct packet_context {\n"
- " uint64_clock_monotonic_t timestamp_begin;\n"
- " uint64_clock_monotonic_t timestamp_end;\n"
- " uint64_t content_size;\n"
- " uint64_t packet_size;\n"
- " uint64_t packet_seq_num;\n"
- " unsigned long events_discarded;\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.
- *
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_event_header_declare(struct lttng_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_clock_monotonic_t timestamp;\n"
- " } compact;\n"
- " struct {\n"
- " uint32_t id;\n"
- " uint64_clock_monotonic_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_clock_monotonic_t timestamp;\n"
- " } compact;\n"
- " struct {\n"
- " uint32_t id;\n"
- " uint64_clock_monotonic_t timestamp;\n"
- " } extended;\n"
- " } v;\n"
- "} align(%u);\n\n",
- lttng_alignof(uint32_t) * CHAR_BIT,
- lttng_alignof(uint16_t) * CHAR_BIT
- );
-}
-
- /*
- * Approximation of NTP time of day to clock monotonic correlation,
- * taken at start of trace.
- * Yes, this is only an approximation. Yes, we can (and will) do better
- * in future versions.
- * This function may return a negative offset. It may happen if the
- * system sets the REALTIME clock to 0 after boot.
- */
-static
-int64_t measure_clock_offset(void)
-{
- uint64_t monotonic_avg, monotonic[2], realtime;
- uint64_t tcf = trace_clock_freq();
- int64_t offset;
- struct timespec rts = { 0, 0 };
- unsigned long flags;
-
- /* Disable interrupts to increase correlation precision. */
- local_irq_save(flags);
- monotonic[0] = trace_clock_read64();
- getnstimeofday(&rts);
- monotonic[1] = trace_clock_read64();
- local_irq_restore(flags);
-
- monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
- realtime = (uint64_t) rts.tv_sec * tcf;
- if (tcf == NSEC_PER_SEC) {
- realtime += rts.tv_nsec;
- } else {
- uint64_t n = rts.tv_nsec * tcf;
-
- do_div(n, NSEC_PER_SEC);
- realtime += n;
- }
- offset = (int64_t) realtime - monotonic_avg;
- return offset;
-}
-
-/*
- * Output metadata into this session's metadata buffers.
- * Must be called with sessions_mutex held.
- */
-static
-int _lttng_session_metadata_statedump(struct lttng_session *session)
-{
- unsigned char *uuid_c = session->uuid.b;
- unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
- struct lttng_channel *chan;
- struct lttng_event *event;
- int ret = 0;
-
- if (!READ_ONCE(session->active))
- return 0;
- if (session->metadata_dumped)
- goto skip_session;
-
- 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 = %u; align = %u; signed = false; } := unsigned long;\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"
- " uint64_t stream_instance_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,
- sizeof(unsigned long) * CHAR_BIT,
- lttng_alignof(unsigned long) * CHAR_BIT,
- CTF_SPEC_MAJOR,
- CTF_SPEC_MINOR,
- uuid_s,
-#if __BYTE_ORDER == __BIG_ENDIAN
- "be"
-#else
- "le"
-#endif
- );
- if (ret)
- goto end;
-
- ret = lttng_metadata_printf(session,
- "env {\n"
- " hostname = \"%s\";\n"
- " domain = \"kernel\";\n"
- " sysname = \"%s\";\n"
- " kernel_release = \"%s\";\n"
- " kernel_version = \"%s\";\n"
- " tracer_name = \"lttng-modules\";\n"
- " tracer_major = %d;\n"
- " tracer_minor = %d;\n"
- " tracer_patchlevel = %d;\n"
- "};\n\n",
- current->nsproxy->uts_ns->name.nodename,
- utsname()->sysname,
- utsname()->release,
- utsname()->version,
- LTTNG_MODULES_MAJOR_VERSION,
- LTTNG_MODULES_MINOR_VERSION,
- LTTNG_MODULES_PATCHLEVEL_VERSION
- );
- if (ret)
- goto end;
-
- ret = lttng_metadata_printf(session,
- "clock {\n"
- " name = \"%s\";\n",
- trace_clock_name()
- );
- if (ret)
- goto end;
-
- if (!trace_clock_uuid(clock_uuid_s)) {
- ret = lttng_metadata_printf(session,
- " uuid = \"%s\";\n",
- clock_uuid_s
- );
- if (ret)
- goto end;
- }
-
- ret = lttng_metadata_printf(session,
- " description = \"%s\";\n"
- " freq = %llu; /* Frequency, in Hz */\n"
- " /* clock value offset from Epoch is: offset * (1/freq) */\n"
- " offset = %lld;\n"
- "};\n\n",
- trace_clock_description(),
- (unsigned long long) trace_clock_freq(),
- (long long) measure_clock_offset()
- );
- if (ret)
- goto end;
-
- ret = lttng_metadata_printf(session,
- "typealias integer {\n"
- " size = 27; align = 1; signed = false;\n"
- " map = clock.%s.value;\n"
- "} := uint27_clock_monotonic_t;\n"
- "\n"
- "typealias integer {\n"
- " size = 32; align = %u; signed = false;\n"
- " map = clock.%s.value;\n"
- "} := uint32_clock_monotonic_t;\n"
- "\n"
- "typealias integer {\n"
- " size = 64; align = %u; signed = false;\n"
- " map = clock.%s.value;\n"
- "} := uint64_clock_monotonic_t;\n\n",
- trace_clock_name(),
- lttng_alignof(uint32_t) * CHAR_BIT,
- trace_clock_name(),
- lttng_alignof(uint64_t) * CHAR_BIT,
- trace_clock_name()
- );
- if (ret)
- goto end;
-
- ret = _lttng_stream_packet_context_declare(session);
- if (ret)
- goto end;
-
- ret = _lttng_event_header_declare(session);
- if (ret)
- goto end;
-
-skip_session:
- list_for_each_entry(chan, &session->chan, list) {
- ret = _lttng_channel_metadata_statedump(session, chan);
- if (ret)
- goto end;
- }
-
- list_for_each_entry(event, &session->events, list) {
- ret = _lttng_event_metadata_statedump(session, event->chan, event);
- if (ret)
- goto end;
- }
- session->metadata_dumped = 1;
-end:
- return ret;
-}
-
-/**
- * lttng_transport_register - LTT transport registration
- * @transport: transport structure
- *
- * Registers a transport which can be used as output to extract the data out of
- * LTTng. The module calling this registration function must ensure that no
- * trap-inducing code will be executed by the transport functions. E.g.
- * vmalloc_sync_all() must be called between a vmalloc and the moment the memory
- * is made visible to the transport function. This registration acts as a
- * vmalloc_sync_all. Therefore, only if the module allocates virtual memory
- * after its registration must it synchronize the TLBs.
- */
-void lttng_transport_register(struct lttng_transport *transport)
-{
- /*
- * Make sure no page fault can be triggered by the module about to be
- * registered. We deal with this here so we don't have to call
- * vmalloc_sync_all() in each module's init.
- */
- wrapper_vmalloc_sync_all();
-
- mutex_lock(&sessions_mutex);
- list_add_tail(&transport->node, <tng_transport_list);
- mutex_unlock(&sessions_mutex);
-}
-EXPORT_SYMBOL_GPL(lttng_transport_register);
-
-/**
- * lttng_transport_unregister - LTT transport unregistration
- * @transport: transport structure
- */
-void lttng_transport_unregister(struct lttng_transport *transport)
-{
- mutex_lock(&sessions_mutex);
- list_del(&transport->node);
- mutex_unlock(&sessions_mutex);
-}
-EXPORT_SYMBOL_GPL(lttng_transport_unregister);
-
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
-
-enum cpuhp_state lttng_hp_prepare;
-enum cpuhp_state lttng_hp_online;
-
-static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
-{
- struct lttng_cpuhp_node *lttng_node;
-
- lttng_node = container_of(node, struct lttng_cpuhp_node, node);
- switch (lttng_node->component) {
- case LTTNG_RING_BUFFER_FRONTEND:
- return 0;
- case LTTNG_RING_BUFFER_BACKEND:
- return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
- case LTTNG_RING_BUFFER_ITER:
- return 0;
- case LTTNG_CONTEXT_PERF_COUNTERS:
- return 0;
- default:
- return -EINVAL;
- }
-}
-
-static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
-{
- struct lttng_cpuhp_node *lttng_node;
-
- lttng_node = container_of(node, struct lttng_cpuhp_node, node);
- switch (lttng_node->component) {
- case LTTNG_RING_BUFFER_FRONTEND:
- return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
- case LTTNG_RING_BUFFER_BACKEND:
- return 0;
- case LTTNG_RING_BUFFER_ITER:
- return 0;
- case LTTNG_CONTEXT_PERF_COUNTERS:
- return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
- default:
- return -EINVAL;
- }
-}
-
-static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
-{
- struct lttng_cpuhp_node *lttng_node;
-
- lttng_node = container_of(node, struct lttng_cpuhp_node, node);
- switch (lttng_node->component) {
- case LTTNG_RING_BUFFER_FRONTEND:
- return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
- case LTTNG_RING_BUFFER_BACKEND:
- return 0;
- case LTTNG_RING_BUFFER_ITER:
- return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
- case LTTNG_CONTEXT_PERF_COUNTERS:
- return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
- default:
- return -EINVAL;
- }
-}
-
-static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
-{
- struct lttng_cpuhp_node *lttng_node;
-
- lttng_node = container_of(node, struct lttng_cpuhp_node, node);
- switch (lttng_node->component) {
- case LTTNG_RING_BUFFER_FRONTEND:
- return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
- case LTTNG_RING_BUFFER_BACKEND:
- return 0;
- case LTTNG_RING_BUFFER_ITER:
- return 0;
- case LTTNG_CONTEXT_PERF_COUNTERS:
- return 0;
- default:
- return -EINVAL;
- }
-}
-
-static int __init lttng_init_cpu_hotplug(void)
-{
- int ret;
-
- ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
- lttng_hotplug_prepare,
- lttng_hotplug_dead);
- if (ret < 0) {
- return ret;
- }
- lttng_hp_prepare = ret;
- lttng_rb_set_hp_prepare(ret);
-
- ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
- lttng_hotplug_online,
- lttng_hotplug_offline);
- if (ret < 0) {
- cpuhp_remove_multi_state(lttng_hp_prepare);
- lttng_hp_prepare = 0;
- return ret;
- }
- lttng_hp_online = ret;
- lttng_rb_set_hp_online(ret);
-
- return 0;
-}
-
-static void __exit lttng_exit_cpu_hotplug(void)
-{
- lttng_rb_set_hp_online(0);
- cpuhp_remove_multi_state(lttng_hp_online);
- lttng_rb_set_hp_prepare(0);
- cpuhp_remove_multi_state(lttng_hp_prepare);
-}
-
-#else /* #if (CONFIG_HOTPLUG_CPU && (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))) */
-static int lttng_init_cpu_hotplug(void)
-{
- return 0;
-}
-static void lttng_exit_cpu_hotplug(void)
-{
-}
-#endif /* #else #if (CONFIG_HOTPLUG_CPU && (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))) */
-
-
-static int __init lttng_events_init(void)
-{
- int ret;
-
- ret = wrapper_lttng_fixup_sig(THIS_MODULE);
- if (ret)
- return ret;
- ret = wrapper_get_pfnblock_flags_mask_init();
- if (ret)
- return ret;
- ret = wrapper_get_pageblock_flags_mask_init();
- if (ret)
- return ret;
- ret = lttng_probes_init();
- if (ret)
- return ret;
- ret = lttng_context_init();
- if (ret)
- return ret;
- ret = lttng_tracepoint_init();
- if (ret)
- goto error_tp;
- event_cache = KMEM_CACHE(lttng_event, 0);
- if (!event_cache) {
- ret = -ENOMEM;
- goto error_kmem;
- }
- ret = lttng_abi_init();
- if (ret)
- goto error_abi;
- ret = lttng_logger_init();
- if (ret)
- goto error_logger;
- ret = lttng_init_cpu_hotplug();
- if (ret)
- goto error_hotplug;
- printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)\n",
- __stringify(LTTNG_MODULES_MAJOR_VERSION),
- __stringify(LTTNG_MODULES_MINOR_VERSION),
- __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
- LTTNG_MODULES_EXTRAVERSION,
- LTTNG_VERSION_NAME);
- return 0;
-
-error_hotplug:
- lttng_logger_exit();
-error_logger:
- lttng_abi_exit();
-error_abi:
- kmem_cache_destroy(event_cache);
-error_kmem:
- lttng_tracepoint_exit();
-error_tp:
- lttng_context_exit();
- printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)\n",
- __stringify(LTTNG_MODULES_MAJOR_VERSION),
- __stringify(LTTNG_MODULES_MINOR_VERSION),
- __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
- LTTNG_MODULES_EXTRAVERSION,
- LTTNG_VERSION_NAME);
- return ret;
-}
-
-module_init(lttng_events_init);
-
-static void __exit lttng_events_exit(void)
-{
- struct lttng_session *session, *tmpsession;
-
- lttng_exit_cpu_hotplug();
- lttng_logger_exit();
- lttng_abi_exit();
- list_for_each_entry_safe(session, tmpsession, &sessions, list)
- lttng_session_destroy(session);
- kmem_cache_destroy(event_cache);
- lttng_tracepoint_exit();
- lttng_context_exit();
- printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)\n",
- __stringify(LTTNG_MODULES_MAJOR_VERSION),
- __stringify(LTTNG_MODULES_MINOR_VERSION),
- __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
- LTTNG_MODULES_EXTRAVERSION,
- LTTNG_VERSION_NAME);
-}
-
-module_exit(lttng_events_exit);
-
-MODULE_LICENSE("GPL and additional rights");
-MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
-MODULE_DESCRIPTION("LTTng Events");
-MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
- __stringify(LTTNG_MODULES_MINOR_VERSION) "."
- __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
- LTTNG_MODULES_EXTRAVERSION);
projects / lttng-modules.git / blobdiff