+/*
+ * ust-metadata.c
+ *
+ * LTTng-UST metadata generation
+ *
+ * Copyright (C) 2010-2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#define _GNU_SOURCE
+#include <stdint.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <limits.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <common/common.h>
+
+#include "ust-registry.h"
+#include "ust-clock.h"
+#include "ust-app.h"
+
+#ifndef max_t
+#define max_t(type, a, b) ((type) ((a) > (b) ? (a) : (b)))
+#endif
+
+static inline
+int fls(unsigned int x)
+{
+ int r = 32;
+
+ if (!x)
+ return 0;
+ if (!(x & 0xFFFF0000U)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xFF000000U)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xF0000000U)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xC0000000U)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x80000000U)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+
+static inline
+int get_count_order(unsigned int count)
+{
+ int order;
+
+ order = fls(count) - 1;
+ if (count & (count - 1))
+ order++;
+ return order;
+}
+
+/*
+ * Returns offset where to write in metadata array, or negative error value on error.
+ */
+static
+ssize_t metadata_reserve(struct ust_registry_session *session, size_t len)
+{
+ size_t new_len = session->metadata_len + len;
+ size_t new_alloc_len = new_len;
+ size_t old_alloc_len = session->metadata_alloc_len;
+ ssize_t ret;
+
+ if (new_alloc_len > (UINT32_MAX >> 1))
+ return -EINVAL;
+ if ((old_alloc_len << 1) > (UINT32_MAX >> 1))
+ return -EINVAL;
+
+ if (new_alloc_len > old_alloc_len) {
+ char *newptr;
+
+ new_alloc_len =
+ max_t(size_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1);
+ newptr = realloc(session->metadata, new_alloc_len);
+ if (!newptr)
+ return -ENOMEM;
+ session->metadata = newptr;
+ /* We zero directly the memory from start of allocation. */
+ memset(&session->metadata[old_alloc_len], 0, new_alloc_len - old_alloc_len);
+ session->metadata_alloc_len = new_alloc_len;
+ }
+ ret = session->metadata_len;
+ session->metadata_len += len;
+ return ret;
+}
+
+/*
+ * We have exclusive access to our metadata buffer (protected by the
+ * ust_lock), so we can do racy operations such as looking for
+ * remaining space left in packet and write, since mutual exclusion
+ * protects us from concurrent writes.
+ */
+static
+int lttng_metadata_printf(struct ust_registry_session *session,
+ const char *fmt, ...)
+{
+ char *str = NULL;
+ size_t len;
+ va_list ap;
+ ssize_t offset;
+ int ret;
+
+ va_start(ap, fmt);
+ ret = vasprintf(&str, fmt, ap);
+ va_end(ap);
+ if (ret < 0)
+ return -ENOMEM;
+
+ len = strlen(str);
+ offset = metadata_reserve(session, len);
+ if (offset < 0) {
+ ret = offset;
+ goto end;
+ }
+ memcpy(&session->metadata[offset], str, len);
+ DBG3("Append to metadata: \"%s\"", str);
+ ret = 0;
+
+end:
+ free(str);
+ return ret;
+}
+
+static
+int _lttng_field_statedump(struct ust_registry_session *session,
+ const struct ustctl_field *field)
+{
+ int ret = 0;
+ const char *bo_be = " byte_order = be;";
+ const char *bo_le = " byte_order = le;";
+ const char *bo_native = "";
+ const char *bo_reverse;
+
+ if (session->byte_order == BIG_ENDIAN)
+ bo_reverse = bo_le;
+ else
+ bo_reverse = bo_be;
+
+ switch (field->type.atype) {
+ case ustctl_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 == ustctl_encode_none)
+ ? "none"
+ : (field->type.u.basic.integer.encoding == ustctl_encode_UTF8)
+ ? "UTF8"
+ : "ASCII",
+ field->type.u.basic.integer.base,
+ field->type.u.basic.integer.reverse_byte_order ? bo_reverse : bo_native,
+ field->name);
+ break;
+ case ustctl_atype_float:
+ ret = lttng_metadata_printf(session,
+ " floating_point { exp_dig = %u; mant_dig = %u; align = %u;%s } _%s;\n",
+ field->type.u.basic._float.exp_dig,
+ field->type.u.basic._float.mant_dig,
+ field->type.u.basic._float.alignment,
+ field->type.u.basic.integer.reverse_byte_order ? bo_reverse : bo_native,
+ field->name);
+ break;
+ case ustctl_atype_enum:
+ return -EINVAL;
+ case ustctl_atype_array:
+ {
+ const struct ustctl_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 == ustctl_encode_none)
+ ? "none"
+ : (elem_type->u.basic.integer.encoding == ustctl_encode_UTF8)
+ ? "UTF8"
+ : "ASCII",
+ elem_type->u.basic.integer.base,
+ elem_type->u.basic.integer.reverse_byte_order ? bo_reverse : bo_native,
+ field->name, field->type.u.array.length);
+ break;
+ }
+ case ustctl_atype_sequence:
+ {
+ const struct ustctl_basic_type *elem_type;
+ const struct ustctl_basic_type *length_type;
+
+ elem_type = &field->type.u.sequence.elem_type;
+ length_type = &field->type.u.sequence.length_type;
+ ret = lttng_metadata_printf(session,
+ " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n",
+ length_type->u.basic.integer.size,
+ (unsigned int) length_type->u.basic.integer.alignment,
+ length_type->u.basic.integer.signedness,
+ (length_type->u.basic.integer.encoding == ustctl_encode_none)
+ ? "none"
+ : ((length_type->u.basic.integer.encoding == ustctl_encode_UTF8)
+ ? "UTF8"
+ : "ASCII"),
+ length_type->u.basic.integer.base,
+ length_type->u.basic.integer.reverse_byte_order ? bo_reverse : bo_native,
+ field->name);
+ if (ret)
+ return ret;
+
+ ret = lttng_metadata_printf(session,
+ " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
+ elem_type->u.basic.integer.size,
+ (unsigned int) elem_type->u.basic.integer.alignment,
+ elem_type->u.basic.integer.signedness,
+ (elem_type->u.basic.integer.encoding == ustctl_encode_none)
+ ? "none"
+ : ((elem_type->u.basic.integer.encoding == ustctl_encode_UTF8)
+ ? "UTF8"
+ : "ASCII"),
+ elem_type->u.basic.integer.base,
+ elem_type->u.basic.integer.reverse_byte_order ? bo_reverse : bo_native,
+ field->name,
+ field->name);
+ break;
+ }
+
+ case ustctl_atype_string:
+ /* Default encoding is UTF8 */
+ ret = lttng_metadata_printf(session,
+ " string%s _%s;\n",
+ field->type.u.basic.string.encoding == ustctl_encode_ASCII ?
+ " { encoding = ASCII; }" : "",
+ field->name);
+ break;
+ default:
+ return -EINVAL;
+ }
+ return ret;
+}
+
+static
+int _lttng_context_metadata_statedump(struct ust_registry_session *session,
+ size_t nr_ctx_fields,
+ struct ustctl_field *ctx)
+{
+ int ret = 0;
+ int i;
+
+ if (!ctx)
+ return 0;
+ for (i = 0; i < nr_ctx_fields; i++) {
+ const struct ustctl_field *field = &ctx[i];
+
+ ret = _lttng_field_statedump(session, field);
+ if (ret)
+ return ret;
+ }
+ return ret;
+}
+
+static
+int _lttng_fields_metadata_statedump(struct ust_registry_session *session,
+ struct ust_registry_event *event)
+{
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < event->nr_fields; i++) {
+ const struct ustctl_field *field = &event->fields[i];
+
+ ret = _lttng_field_statedump(session, field);
+ if (ret)
+ return ret;
+ }
+ return ret;
+}
+
+/*
+ * Should be called with session registry mutex held.
+ */
+int ust_metadata_event_statedump(struct ust_registry_session *session,
+ struct ust_registry_channel *chan,
+ struct ust_registry_event *event)
+{
+ int ret = 0;
+
+ /* Don't dump metadata events */
+ if (chan->chan_id == -1U)
+ return 0;
+
+ ret = lttng_metadata_printf(session,
+ "event {\n"
+ " name = \"%s\";\n"
+ " id = %u;\n"
+ " stream_id = %u;\n",
+ event->name,
+ event->id,
+ chan->chan_id);
+ if (ret)
+ goto end;
+
+ ret = lttng_metadata_printf(session,
+ " loglevel = %d;\n",
+ event->loglevel);
+ if (ret)
+ goto end;
+
+ if (event->model_emf_uri) {
+ ret = lttng_metadata_printf(session,
+ " model.emf.uri = \"%s\";\n",
+ event->model_emf_uri);
+ if (ret)
+ goto end;
+ }
+
+#if 0 /* context for events not supported */
+ 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;
+ }
+#endif
+ ret = lttng_metadata_printf(session,
+ " fields := struct {\n"
+ );
+ if (ret)
+ goto end;
+
+ ret = _lttng_fields_metadata_statedump(session, event);
+ if (ret)
+ goto end;
+
+ ret = lttng_metadata_printf(session,
+ " };\n"
+ "};\n\n");
+ if (ret)
+ goto end;
+
+end:
+ return ret;
+}
+
+/*
+ * Should be called with session registry mutex held.
+ */
+int ust_metadata_channel_statedump(struct ust_registry_session *session,
+ struct ust_registry_channel *chan)
+{
+ int ret = 0;
+
+ /* Don't dump metadata events */
+ if (chan->chan_id == -1U)
+ return 0;
+
+ if (!chan->header_type)
+ return -EINVAL;
+
+ ret = lttng_metadata_printf(session,
+ "stream {\n"
+ " id = %u;\n"
+ " event.header := %s;\n"
+ " packet.context := struct packet_context;\n",
+ chan->chan_id,
+ chan->header_type == USTCTL_CHANNEL_HEADER_COMPACT ?
+ "struct event_header_compact" :
+ "struct event_header_large");
+ if (ret)
+ goto end;
+
+ if (chan->ctx_fields) {
+ ret = lttng_metadata_printf(session,
+ " event.context := struct {\n");
+ if (ret)
+ goto end;
+ }
+ ret = _lttng_context_metadata_statedump(session,
+ chan->nr_ctx_fields,
+ chan->ctx_fields);
+ if (ret)
+ goto end;
+ if (chan->ctx_fields) {
+ ret = lttng_metadata_printf(session,
+ " };\n");
+ if (ret)
+ goto end;
+ }
+
+ ret = lttng_metadata_printf(session,
+ "};\n\n");
+
+end:
+ return ret;
+}
+
+static
+int _lttng_stream_packet_context_declare(struct ust_registry_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"
+ " 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.
+ */
+static
+int _lttng_event_header_declare(struct ust_registry_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",
+ session->uint32_t_alignment,
+ session->uint16_t_alignment
+ );
+}
+
+/*
+ * 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.
+ */
+static
+uint64_t measure_clock_offset(void)
+{
+ uint64_t offset, monotonic[2], realtime;
+ struct timespec rts = { 0, 0 };
+ int ret;
+
+ monotonic[0] = trace_clock_read64();
+ ret = clock_gettime(CLOCK_REALTIME, &rts);
+ if (ret < 0)
+ return 0;
+ monotonic[1] = trace_clock_read64();
+ offset = (monotonic[0] + monotonic[1]) >> 1;
+ realtime = (uint64_t) rts.tv_sec * 1000000000ULL;
+ realtime += rts.tv_nsec;
+ offset = realtime - offset;
+ return offset;
+}
+
+
+/*
+ * Should be called with session registry mutex held.
+ */
+int ust_metadata_session_statedump(struct ust_registry_session *session,
+ struct ust_app *app)
+{
+ unsigned char *uuid_c;
+ char uuid_s[UUID_STR_LEN],
+ clock_uuid_s[UUID_STR_LEN];
+ int ret = 0;
+ char hostname[HOST_NAME_MAX];
+
+ uuid_c = session->uuid;
+
+ 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"
+ " };\n"
+ "};\n\n",
+ session->uint8_t_alignment,
+ session->uint16_t_alignment,
+ session->uint32_t_alignment,
+ session->uint64_t_alignment,
+ session->bits_per_long,
+ session->long_alignment,
+ CTF_SPEC_MAJOR,
+ CTF_SPEC_MINOR,
+ uuid_s,
+ session->byte_order == BIG_ENDIAN ? "be" : "le"
+ );
+ if (ret)
+ goto end;
+
+ /* ignore error, just use empty string if error. */
+ hostname[0] = '\0';
+ ret = gethostname(hostname, sizeof(hostname));
+ if (ret && errno == ENAMETOOLONG)
+ hostname[HOST_NAME_MAX - 1] = '\0';
+ ret = lttng_metadata_printf(session,
+ "env {\n"
+ " hostname = \"%s\";\n"
+ " domain = \"ust\";\n"
+ " tracer_name = \"lttng-ust\";\n"
+ " tracer_major = %u;\n"
+ " tracer_minor = %u;\n"
+ " tracer_patchlevel = %u;\n"
+ "};\n\n",
+ hostname,
+ app->version.major,
+ app->version.minor,
+ app->version.patchlevel
+ );
+ if (ret)
+ goto end;
+
+ /*
+ * If per-application registry, we can output extra information
+ * about the application.
+ */
+ if (app) {
+ ret = lttng_metadata_printf(session,
+ " vpid = %d;\n"
+ " procname = \"%s\";\n"
+ "};\n\n",
+ (int) app->pid,
+ app->name
+ );
+ if (ret)
+ goto end;
+ }
+
+ ret = lttng_metadata_printf(session,
+ "};\n\n"
+ );
+ if (ret)
+ goto end;
+
+
+ ret = lttng_metadata_printf(session,
+ "clock {\n"
+ " name = %s;\n",
+ "monotonic"
+ );
+ 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 = \"Monotonic Clock\";\n"
+ " freq = %" PRIu64 "; /* Frequency, in Hz */\n"
+ " /* clock value offset from Epoch is: offset * (1/freq) */\n"
+ " offset = %" PRIu64 ";\n"
+ "};\n\n",
+ trace_clock_freq(),
+ measure_clock_offset()
+ );
+ if (ret)
+ goto end;
+
+ ret = lttng_metadata_printf(session,
+ "typealias integer {\n"
+ " size = 27; align = 1; signed = false;\n"
+ " map = clock.monotonic.value;\n"
+ "} := uint27_clock_monotonic_t;\n"
+ "\n"
+ "typealias integer {\n"
+ " size = 32; align = %u; signed = false;\n"
+ " map = clock.monotonic.value;\n"
+ "} := uint32_clock_monotonic_t;\n"
+ "\n"
+ "typealias integer {\n"
+ " size = 64; align = %u; signed = false;\n"
+ " map = clock.monotonic.value;\n"
+ "} := uint64_clock_monotonic_t;\n\n",
+ session->uint32_t_alignment,
+ session->uint64_t_alignment
+ );
+ 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;
+
+end:
+ return ret;
+}
projects / lttng-tools.git / commitdiff
