#include <linux/jhash.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
-#include <linux/uuid.h>
#include <linux/dmi.h>
-#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_all() */
+#include <wrapper/uuid.h>
+#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
#include <wrapper/random.h>
#include <wrapper/tracepoint.h>
#include <wrapper/list.h>
goto err;
INIT_LIST_HEAD(&session->chan);
INIT_LIST_HEAD(&session->events);
- uuid_le_gen(&session->uuid);
+ lttng_guid_gen(&session->uuid);
metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
GFP_KERNEL);
BUG_ON(chan->channel_type == METADATA_CHANNEL);
_lttng_channel_destroy(chan);
}
+ mutex_lock(&session->metadata_cache->lock);
list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list)
_lttng_metadata_channel_hangup(metadata_stream);
+ mutex_unlock(&session->metadata_cache->lock);
lttng_id_tracker_destroy(&session->pid_tracker, false);
lttng_id_tracker_destroy(&session->vpid_tracker, false);
lttng_id_tracker_destroy(&session->uid_tracker, false);
ret = -EINVAL;
break;
case LTTNG_KERNEL_KPROBE:
- case LTTNG_KERNEL_FUNCTION:
case LTTNG_KERNEL_UPROBE:
case LTTNG_KERNEL_NOOP:
WRITE_ONCE(event->enabled, 1);
case LTTNG_KERNEL_KRETPROBE:
ret = lttng_kretprobes_event_enable_state(event, 1);
break;
+ case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
default:
WARN_ON_ONCE(1);
ret = -EINVAL;
ret = -EINVAL;
break;
case LTTNG_KERNEL_KPROBE:
- case LTTNG_KERNEL_FUNCTION:
case LTTNG_KERNEL_UPROBE:
case LTTNG_KERNEL_NOOP:
WRITE_ONCE(event->enabled, 0);
case LTTNG_KERNEL_KRETPROBE:
ret = lttng_kretprobes_event_enable_state(event, 0);
break;
+ case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
default:
WARN_ON_ONCE(1);
ret = -EINVAL;
case LTTNG_KERNEL_KPROBE:
case LTTNG_KERNEL_UPROBE:
case LTTNG_KERNEL_KRETPROBE:
- case LTTNG_KERNEL_FUNCTION:
case LTTNG_KERNEL_NOOP:
case LTTNG_KERNEL_SYSCALL:
event_name = event_param->name;
break;
+ case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
default:
WARN_ON_ONCE(1);
ret = -EINVAL;
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:
/*
ret = try_module_get(event->desc->owner);
WARN_ON_ONCE(!ret);
break;
+ case LTTNG_KERNEL_FUNCTION: /* Fall-through */
default:
WARN_ON_ONCE(1);
ret = -EINVAL;
case LTTNG_KERNEL_KPROBE:
case LTTNG_KERNEL_UPROBE:
case LTTNG_KERNEL_KRETPROBE:
- case LTTNG_KERNEL_FUNCTION:
case LTTNG_KERNEL_NOOP:
ret = 0;
break;
+ case LTTNG_KERNEL_FUNCTION: /* Fall-through */
default:
WARN_ON_ONCE(1);
}
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);
lttng_uprobes_unregister(event);
ret = 0;
break;
+ case LTTNG_KERNEL_FUNCTION: /* Fall-through */
default:
WARN_ON_ONCE(1);
}
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;
module_put(event->desc->owner);
lttng_uprobes_destroy_private(event);
break;
+ case LTTNG_KERNEL_FUNCTION: /* Fall-through */
default:
WARN_ON_ONCE(1);
}
* was written and a negative value on error.
*/
int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
- struct channel *chan)
+ struct channel *chan, bool *coherent)
{
struct lib_ring_buffer_ctx ctx;
int ret = 0;
ret = stream->transport->ops.event_reserve(&ctx, 0);
if (ret != 0) {
printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
+ stream->coherent = false;
goto end;
}
stream->transport->ops.event_write(&ctx,
reserve_len);
stream->transport->ops.event_commit(&ctx);
stream->metadata_in += reserve_len;
+ if (reserve_len < len)
+ stream->coherent = false;
+ else
+ stream->coherent = true;
ret = reserve_len;
end:
+ if (coherent)
+ *coherent = stream->coherent;
mutex_unlock(&stream->metadata_cache->lock);
return ret;
}
+static
+void lttng_metadata_begin(struct lttng_session *session)
+{
+ if (atomic_inc_return(&session->metadata_cache->producing) == 1)
+ mutex_lock(&session->metadata_cache->lock);
+}
+
+static
+void lttng_metadata_end(struct lttng_session *session)
+{
+ WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
+ if (atomic_dec_return(&session->metadata_cache->producing) == 0) {
+ struct lttng_metadata_stream *stream;
+
+ list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list)
+ wake_up_interruptible(&stream->read_wait);
+ mutex_unlock(&session->metadata_cache->lock);
+ }
+}
+
/*
* 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.
+ * The content of the printf is printed as a single atomic metadata
+ * transaction.
*/
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));
+ WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
va_start(ap, fmt);
str = kvasprintf(GFP_KERNEL, fmt, ap);
return -ENOMEM;
len = strlen(str);
- mutex_lock(&session->metadata_cache->lock);
+ WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
if (session->metadata_cache->metadata_written + len >
session->metadata_cache->cache_alloc) {
char *tmp_cache_realloc;
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;
}
/*
* Must be called with sessions_mutex held.
+ * The entire event metadata is printed as a single atomic metadata
+ * transaction.
*/
static
int _lttng_event_metadata_statedump(struct lttng_session *session,
{
int ret = 0;
- if (event->metadata_dumped || !READ_ONCE(session->active))
+ if (event->metadata_dumped || !LTTNG_READ_ONCE(session->active))
return 0;
if (chan->channel_type == METADATA_CHANNEL)
return 0;
+ lttng_metadata_begin(session);
+
ret = lttng_metadata_printf(session,
"event {\n"
" name = \"%s\";\n"
event->metadata_dumped = 1;
end:
+ lttng_metadata_end(session);
return ret;
}
/*
* Must be called with sessions_mutex held.
+ * The entire channel metadata is printed as a single atomic metadata
+ * transaction.
*/
static
int _lttng_channel_metadata_statedump(struct lttng_session *session,
{
int ret = 0;
- if (chan->metadata_dumped || !READ_ONCE(session->active))
+ if (chan->metadata_dumped || !LTTNG_READ_ONCE(session->active))
return 0;
if (chan->channel_type == METADATA_CHANNEL)
return 0;
+ lttng_metadata_begin(session);
+
WARN_ON_ONCE(!chan->header_type);
ret = lttng_metadata_printf(session,
"stream {\n"
chan->metadata_dumped = 1;
end:
+ lttng_metadata_end(session);
return ret;
}
static
int print_escaped_ctf_string(struct lttng_session *session, const char *string)
{
- int ret;
+ int ret = 0;
size_t i;
char cur;
struct lttng_event *event;
int ret = 0;
- if (!READ_ONCE(session->active))
+ if (!LTTNG_READ_ONCE(session->active))
return 0;
+
+ lttng_metadata_begin(session);
+
if (session->metadata_dumped)
goto skip_session;
}
session->metadata_dumped = 1;
end:
+ lttng_metadata_end(session);
return ret;
}
* 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
+ * vmalloc_sync_mappings() 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
+ * vmalloc_sync_mappings. 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.
+ * vmalloc_sync_mappings() in each module's init.
*/
- wrapper_vmalloc_sync_all();
+ wrapper_vmalloc_sync_mappings();
mutex_lock(&sessions_mutex);
list_add_tail(&transport->node, <tng_transport_list);