#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
+#include <linux/uuid.h>
#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
#include "ltt-events.h"
#include "ltt-tracer.h"
static DEFINE_MUTEX(sessions_mutex);
static struct kmem_cache *event_cache;
+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,
return NULL;
INIT_LIST_HEAD(&session->chan);
INIT_LIST_HEAD(&session->events);
+ uuid_le_gen(&session->uuid);
list_add(&session->list, &sessions);
mutex_unlock(&sessions_mutex);
return session;
}
ACCESS_ONCE(session->active) = 1;
+ ACCESS_ONCE(session->been_active) = 1;
synchronize_trace(); /* Wait for in-flight events to complete */
ret = _ltt_session_metadata_statedump(session);
if (ret) {
struct ltt_transport *transport;
mutex_lock(&sessions_mutex);
- if (session->active) {
- printk(KERN_WARNING "LTTng refusing to add channel to active session\n");
+ if (session->been_active)
goto active; /* Refuse to add channel to active session */
- }
transport = ltt_transport_find(transport_name);
if (!transport) {
printk(KERN_WARNING "LTTng transport %s not found\n",
goto nomem;
chan->session = session;
init_waitqueue_head(&chan->notify_wait);
- chan->chan = transport->ops.channel_create("[lttng]", session, buf_addr,
+ 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.
+ */
+ chan->chan = transport->ops.channel_create("[lttng]", chan, buf_addr,
subbuf_size, num_subbuf, switch_timer_interval,
read_timer_interval);
if (!chan->chan)
goto create_error;
- chan->id = session->free_chan_id++;
chan->ops = &transport->ops;
list_add(&chan->list, &session->chan);
mutex_unlock(&sessions_mutex);
/*
* Only used internally at session destruction.
*/
+static
void _ltt_channel_destroy(struct ltt_channel *chan)
{
chan->ops->channel_destroy(chan->chan);
list_del(&chan->list);
+ lttng_destroy_context(chan->ctx);
kfree(chan);
}
/*
* Supports event creation while tracing session is active.
*/
-struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
- enum instrum_type itype,
- const struct lttng_event_desc *event_desc,
+struct ltt_event *ltt_event_create(struct ltt_channel *chan,
+ struct lttng_kernel_event *event_param,
void *filter)
{
struct ltt_event *event;
* creation). Might require a hash if we have lots of events.
*/
list_for_each_entry(event, &chan->session->events, list)
- if (!strcmp(event->desc->name, name))
+ if (!strcmp(event->desc->name, event_param->name))
goto exist;
event = kmem_cache_zalloc(event_cache, GFP_KERNEL);
if (!event)
goto cache_error;
event->chan = chan;
- event->desc = event_desc;
event->filter = filter;
event->id = chan->free_event_id++;
- event->itype = itype;
+ event->instrumentation = event_param->instrumentation;
/* Populate ltt_event structure before tracepoint registration. */
smp_wmb();
- switch (itype) {
- case INSTRUM_TRACEPOINTS:
- ret = tracepoint_probe_register(name, event_desc->probe_callback,
- event);
+ switch (event_param->instrumentation) {
+ case LTTNG_KERNEL_TRACEPOINT:
+ event->desc = ltt_event_get(event_param->name);
+ if (!event->desc)
+ goto register_error;
+ ret = tracepoint_probe_register(event_param->name,
+ event->desc->probe_callback,
+ event);
if (ret)
goto register_error;
break;
+ case LTTNG_KERNEL_KPROBE:
+ ret = lttng_kprobes_register(event_param->name,
+ event_param->u.kprobe.symbol_name,
+ event_param->u.kprobe.offset,
+ event_param->u.kprobe.addr,
+ event);
+ if (ret)
+ goto register_error;
+ ret = try_module_get(event->desc->owner);
+ WARN_ON_ONCE(!ret);
+ break;
+ case LTTNG_KERNEL_FUNCTION:
+ ret = lttng_ftrace_register(event_param->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;
default:
WARN_ON_ONCE(1);
}
return event;
statedump_error:
- WARN_ON_ONCE(tracepoint_probe_unregister(name, event_desc->probe_callback,
- event));
+ WARN_ON_ONCE(tracepoint_probe_unregister(event_param->name,
+ event->desc->probe_callback,
+ event));
+ ltt_event_put(event->desc);
register_error:
kmem_cache_free(event_cache, event);
cache_error:
{
int ret = -EINVAL;
- switch (event->itype) {
- case INSTRUM_TRACEPOINTS:
+ switch (event->instrumentation) {
+ case LTTNG_KERNEL_TRACEPOINT:
ret = tracepoint_probe_unregister(event->desc->name,
event->desc->probe_callback,
event);
if (ret)
return ret;
break;
+ case LTTNG_KERNEL_KPROBE:
+ lttng_kprobes_unregister(event);
+ ret = 0;
+ break;
+ case LTTNG_KERNEL_FUNCTION:
+ lttng_ftrace_unregister(event);
+ ret = 0;
+ break;
default:
WARN_ON_ONCE(1);
}
/*
* Only used internally at session destruction.
*/
+static
void _ltt_event_destroy(struct ltt_event *event)
{
- ltt_event_put(event->desc);
+ switch (event->instrumentation) {
+ case LTTNG_KERNEL_TRACEPOINT:
+ ltt_event_put(event->desc);
+ break;
+ case LTTNG_KERNEL_KPROBE:
+ module_put(event->desc->owner);
+ lttng_kprobes_destroy_private(event);
+ break;
+ case LTTNG_KERNEL_FUNCTION:
+ module_put(event->desc->owner);
+ lttng_ftrace_destroy_private(event);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ }
list_del(&event->list);
+ lttng_destroy_context(event->ctx);
kmem_cache_free(event_cache, event);
}
+/*
+ * We have exclusive access to our metadata buffer (protected by the
+ * sessions_mutex), 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 ltt_channel *chan = session->metadata;
char *str;
int ret = 0, waitret;
- size_t len;
+ size_t len, reserve_len, pos;
va_list ap;
WARN_ON_ONCE(!ACCESS_ONCE(session->active));
if (!str)
return -ENOMEM;
- len = strlen(str) + 1;
- lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, len, sizeof(char), -1);
- /*
- * 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_event_interruptible_timeout(*chan->ops->get_reader_wait_queue(chan),
- ({
- ret = chan->ops->event_reserve(&ctx);
- ret != -ENOBUFS || !ret;
- }),
- msecs_to_jiffies(LTTNG_METADATA_TIMEOUT_MSEC));
- if (waitret || ret) {
- printk(KERN_WARNING "LTTng: Failure to write metadata to buffers (%s)\n",
- waitret == -ERESTARTSYS ? "interrupted" :
- (ret == -ENOBUFS ? "timeout" : "I/O error"));
- if (waitret == -ERESTARTSYS)
- ret = waitret;
- goto end;
+ 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),
+ len - pos);
+ lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len,
+ sizeof(char), -1);
+ /*
+ * 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_event_interruptible_timeout(*chan->ops->get_reader_wait_queue(chan),
+ ({
+ ret = chan->ops->event_reserve(&ctx, 0);
+ ret != -ENOBUFS || !ret;
+ }),
+ msecs_to_jiffies(LTTNG_METADATA_TIMEOUT_MSEC));
+ if (!waitret || waitret == -ERESTARTSYS || ret) {
+ printk(KERN_WARNING "LTTng: Failure to write metadata to buffers (%s)\n",
+ waitret == -ERESTARTSYS ? "interrupted" :
+ (ret == -ENOBUFS ? "timeout" : "I/O error"));
+ if (waitret == -ERESTARTSYS)
+ ret = waitret;
+ goto end;
+ }
+ chan->ops->event_write(&ctx, &str[pos], len);
+ chan->ops->event_commit(&ctx);
}
- chan->ops->event_write(&ctx, str, len);
- chan->ops->event_commit(&ctx);
end:
kfree(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,
+#ifdef __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,
+#ifdef __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",
+ " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s[ __%s_length ];\n",
+ length_type->u.basic.integer.size,
+ 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,
+#ifdef __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,
+ 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,
+#ifdef __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)
for (i = 0; i < desc->nr_fields; i++) {
const struct lttng_event_field *field = &desc->fields[i];
- switch (field->type.atype) {
- case atype_integer:
- ret = lttng_metadata_printf(session,
- " integer { size = %u; align = %u; signed = %u;%s } %s;\n",
- field->type.u.basic.integer.size,
- field->type.u.basic.integer.alignment,
- field->type.u.basic.integer.signedness,
-#ifdef __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:
- break;
- case atype_sequence:
- break;
-
- case atype_string:
- 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;
- }
+ ret = _ltt_field_statedump(session, field);
+ if (ret)
+ return ret;
}
return ret;
}
"event {\n"
" name = %s;\n"
" id = %u;\n"
- " stream_id = %u;\n"
- " event.fields := struct {\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;
* byte size.
*/
ret = lttng_metadata_printf(session,
- " } aligned(%u);\n"
- "};\n", ltt_get_header_alignment());
+ " };\n"
+ "};\n\n");
if (ret)
goto end;
-
-
-
event->metadata_dumped = 1;
end:
return ret;
ret = lttng_metadata_printf(session,
"stream {\n"
" id = %u;\n"
- " event.header := %s;\n",
- "};\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",
+ ltt_alignof(uint32_t) * CHAR_BIT,
+ ltt_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.b;
+ unsigned char uuid_s[37];
struct ltt_channel *chan;
struct ltt_event *event;
int ret = 0;
return 0;
if (session->metadata_dumped)
goto skip_session;
+ if (!session->metadata) {
+ printk(KERN_WARNING "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",
+ ltt_alignof(uint8_t) * CHAR_BIT,
+ ltt_alignof(uint16_t) * CHAR_BIT,
+ ltt_alignof(uint32_t) * CHAR_BIT,
+ ltt_alignof(uint64_t) * CHAR_BIT,
+ CTF_VERSION_MAJOR,
+ CTF_VERSION_MINOR,
+ uuid_s,
+#ifdef __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:
list_for_each_entry(chan, &session->chan, list) {
}
list_for_each_entry(event, &session->events, list) {
- ret = _ltt_event_metadata_statedump(session, chan, event);
+ ret = _ltt_event_metadata_statedump(session, event->chan, event);
if (ret)
goto end;
}
projects / lttng-modules.git / blobdiff