+++ /dev/null
-/*
- * SPDX-License-Identifier: LGPL-2.1-only
- *
- * Copyright 2010-2012 (C) Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * Holds LTTng probes registry.
- */
-
-#define _LGPL_SOURCE
-#include <string.h>
-#include <errno.h>
-#include <urcu/list.h>
-#include <urcu/hlist.h>
-#include <lttng/ust-events.h>
-#include <lttng/tracepoint.h>
-#include "tracepoint-internal.h"
-#include <assert.h>
-#include <ust-helper.h>
-#include <ctype.h>
-
-#include "lttng-tracer-core.h"
-#include "jhash.h"
-#include "error.h"
-#include "ust-events-internal.h"
-
-/*
- * probe list is protected by ust_lock()/ust_unlock().
- */
-static CDS_LIST_HEAD(_probe_list);
-
-/*
- * List of probes registered by not yet processed.
- */
-static CDS_LIST_HEAD(lazy_probe_init);
-
-/*
- * lazy_nesting counter ensures we don't trigger lazy probe registration
- * fixup while we are performing the fixup. It is protected by the ust
- * mutex.
- */
-static int lazy_nesting;
-
-/*
- * Validate that each event within the probe provider refers to the
- * right probe, and that the resulting name is not too long.
- */
-static
-bool check_event_provider(struct lttng_ust_probe_desc *probe_desc)
-{
- int i;
-
- for (i = 0; i < probe_desc->nr_events; i++) {
- const struct lttng_ust_event_desc *event_desc = probe_desc->event_desc[i];
-
- if (event_desc->probe_desc != probe_desc) {
- ERR("Error registering probe provider '%s'. Event '%s:%s' refers to the wrong provider descriptor.",
- probe_desc->provider_name, probe_desc->provider_name, event_desc->event_name);
- return false; /* provider mismatch */
- }
- if (!lttng_ust_validate_event_name(event_desc)) {
- ERR("Error registering probe provider '%s'. Event '%s:%s' name is too long.",
- probe_desc->provider_name, probe_desc->provider_name, event_desc->event_name);
- return false; /* provider mismatch */
- }
- }
- return true;
-}
-
-/*
- * Called under ust lock.
- */
-static
-void lttng_lazy_probe_register(struct lttng_ust_probe_desc *desc)
-{
- struct lttng_ust_probe_desc *iter;
- struct cds_list_head *probe_list;
-
- /*
- * The provider ensures there are no duplicate event names.
- * Duplicated TRACEPOINT_EVENT event names would generate a
- * compile-time error due to duplicated symbol names.
- */
-
- /*
- * We sort the providers by struct lttng_ust_probe_desc pointer
- * address.
- */
- probe_list = &_probe_list;
- cds_list_for_each_entry_reverse(iter, probe_list, head) {
- BUG_ON(iter == desc); /* Should never be in the list twice */
- if (iter < desc) {
- /* We belong to the location right after iter. */
- cds_list_add(&desc->head, &iter->head);
- goto desc_added;
- }
- }
- /* We should be added at the head of the list */
- cds_list_add(&desc->head, probe_list);
-desc_added:
- DBG("just registered probe %s containing %u events",
- desc->provider_name, desc->nr_events);
-}
-
-/*
- * Called under ust lock.
- */
-static
-void fixup_lazy_probes(void)
-{
- struct lttng_ust_probe_desc *iter, *tmp;
- int ret;
-
- lazy_nesting++;
- cds_list_for_each_entry_safe(iter, tmp,
- &lazy_probe_init, lazy_init_head) {
- lttng_lazy_probe_register(iter);
- iter->lazy = 0;
- cds_list_del(&iter->lazy_init_head);
- }
- ret = lttng_fix_pending_events();
- assert(!ret);
- lazy_nesting--;
-}
-
-/*
- * Called under ust lock.
- */
-struct cds_list_head *lttng_get_probe_list_head(void)
-{
- if (!lazy_nesting && !cds_list_empty(&lazy_probe_init))
- fixup_lazy_probes();
- return &_probe_list;
-}
-
-static
-int check_provider_version(struct lttng_ust_probe_desc *desc)
-{
- /*
- * Check tracepoint provider version compatibility.
- */
- if (desc->major <= LTTNG_UST_PROVIDER_MAJOR) {
- DBG("Provider \"%s\" accepted, version %u.%u is compatible "
- "with LTTng UST provider version %u.%u.",
- desc->provider_name, desc->major, desc->minor,
- LTTNG_UST_PROVIDER_MAJOR,
- LTTNG_UST_PROVIDER_MINOR);
- if (desc->major < LTTNG_UST_PROVIDER_MAJOR) {
- DBG("However, some LTTng UST features might not be "
- "available for this provider unless it is "
- "recompiled against a more recent LTTng UST.");
- }
- return 1; /* accept */
- } else {
- ERR("Provider \"%s\" rejected, version %u.%u is incompatible "
- "with LTTng UST provider version %u.%u. Please upgrade "
- "LTTng UST.",
- desc->provider_name, desc->major, desc->minor,
- LTTNG_UST_PROVIDER_MAJOR,
- LTTNG_UST_PROVIDER_MINOR);
- return 0; /* reject */
- }
-}
-
-
-int lttng_ust_probe_register(struct lttng_ust_probe_desc *desc)
-{
- int ret = 0;
-
- lttng_ust_fixup_tls();
-
- /*
- * If version mismatch, don't register, but don't trigger assert
- * on caller. The version check just prints an error.
- */
- if (!check_provider_version(desc))
- return 0;
- if (!check_event_provider(desc))
- return 0;
-
- ust_lock_nocheck();
-
- cds_list_add(&desc->lazy_init_head, &lazy_probe_init);
- desc->lazy = 1;
- DBG("adding probe %s containing %u events to lazy registration list",
- desc->provider_name, desc->nr_events);
- /*
- * If there is at least one active session, we need to register
- * the probe immediately, since we cannot delay event
- * registration because they are needed ASAP.
- */
- if (lttng_session_active())
- fixup_lazy_probes();
-
- lttng_fix_pending_event_notifiers();
-
- ust_unlock();
- return ret;
-}
-
-void lttng_ust_probe_unregister(struct lttng_ust_probe_desc *desc)
-{
- lttng_ust_fixup_tls();
-
- if (!check_provider_version(desc))
- return;
-
- ust_lock_nocheck();
- if (!desc->lazy)
- cds_list_del(&desc->head);
- else
- cds_list_del(&desc->lazy_init_head);
-
- lttng_probe_provider_unregister_events(desc);
- DBG("just unregistered probes of provider %s", desc->provider_name);
-
- ust_unlock();
-}
-
-void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list)
-{
- struct tp_list_entry *list_entry, *tmp;
-
- cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
- cds_list_del(&list_entry->head);
- free(list_entry);
- }
-}
-
-/*
- * called with UST lock held.
- */
-int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list)
-{
- struct lttng_ust_probe_desc *probe_desc;
- int i;
- struct cds_list_head *probe_list;
-
- probe_list = lttng_get_probe_list_head();
- CDS_INIT_LIST_HEAD(&list->head);
- cds_list_for_each_entry(probe_desc, probe_list, head) {
- for (i = 0; i < probe_desc->nr_events; i++) {
- const struct lttng_ust_event_desc *event_desc =
- probe_desc->event_desc[i];
- struct tp_list_entry *list_entry;
-
- /* Skip event if name is too long. */
- if (!lttng_ust_validate_event_name(event_desc))
- continue;
- list_entry = zmalloc(sizeof(*list_entry));
- if (!list_entry)
- goto err_nomem;
- cds_list_add(&list_entry->head, &list->head);
- lttng_ust_format_event_name(event_desc, list_entry->tp.name);
- if (!event_desc->loglevel) {
- list_entry->tp.loglevel = TRACE_DEFAULT;
- } else {
- list_entry->tp.loglevel = *(*event_desc->loglevel);
- }
- }
- }
- if (cds_list_empty(&list->head))
- list->iter = NULL;
- else
- list->iter =
- cds_list_first_entry(&list->head, struct tp_list_entry, head);
- return 0;
-
-err_nomem:
- lttng_probes_prune_event_list(list);
- return -ENOMEM;
-}
-
-/*
- * Return current iteration position, advance internal iterator to next.
- * Return NULL if end of list.
- */
-struct lttng_ust_abi_tracepoint_iter *
- lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list)
-{
- struct tp_list_entry *entry;
-
- if (!list->iter)
- return NULL;
- entry = list->iter;
- if (entry->head.next == &list->head)
- list->iter = NULL;
- else
- list->iter = cds_list_entry(entry->head.next,
- struct tp_list_entry, head);
- return &entry->tp;
-}
-
-void lttng_probes_prune_field_list(struct lttng_ust_field_list *list)
-{
- struct tp_field_list_entry *list_entry, *tmp;
-
- cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) {
- cds_list_del(&list_entry->head);
- free(list_entry);
- }
-}
-
-/*
- * called with UST lock held.
- */
-int lttng_probes_get_field_list(struct lttng_ust_field_list *list)
-{
- struct lttng_ust_probe_desc *probe_desc;
- int i;
- struct cds_list_head *probe_list;
-
- probe_list = lttng_get_probe_list_head();
- CDS_INIT_LIST_HEAD(&list->head);
- cds_list_for_each_entry(probe_desc, probe_list, head) {
- for (i = 0; i < probe_desc->nr_events; i++) {
- const struct lttng_ust_event_desc *event_desc =
- probe_desc->event_desc[i];
- int j;
-
- if (event_desc->nr_fields == 0) {
- /* Events without fields. */
- struct tp_field_list_entry *list_entry;
-
- /* Skip event if name is too long. */
- if (!lttng_ust_validate_event_name(event_desc))
- continue;
- list_entry = zmalloc(sizeof(*list_entry));
- if (!list_entry)
- goto err_nomem;
- cds_list_add(&list_entry->head, &list->head);
- lttng_ust_format_event_name(event_desc, list_entry->field.event_name);
- list_entry->field.field_name[0] = '\0';
- list_entry->field.type = LTTNG_UST_ABI_FIELD_OTHER;
- if (!event_desc->loglevel) {
- list_entry->field.loglevel = TRACE_DEFAULT;
- } else {
- list_entry->field.loglevel = *(*event_desc->loglevel);
- }
- list_entry->field.nowrite = 1;
- }
-
- for (j = 0; j < event_desc->nr_fields; j++) {
- const struct lttng_ust_event_field *event_field =
- event_desc->fields[j];
- struct tp_field_list_entry *list_entry;
-
- /* Skip event if name is too long. */
- if (!lttng_ust_validate_event_name(event_desc))
- continue;
- list_entry = zmalloc(sizeof(*list_entry));
- if (!list_entry)
- goto err_nomem;
- cds_list_add(&list_entry->head, &list->head);
- lttng_ust_format_event_name(event_desc, list_entry->field.event_name);
- strncpy(list_entry->field.field_name,
- event_field->name,
- LTTNG_UST_ABI_SYM_NAME_LEN);
- list_entry->field.field_name[LTTNG_UST_ABI_SYM_NAME_LEN - 1] = '\0';
- switch (event_field->type->type) {
- case lttng_ust_type_integer:
- list_entry->field.type = LTTNG_UST_ABI_FIELD_INTEGER;
- break;
- case lttng_ust_type_string:
- list_entry->field.type = LTTNG_UST_ABI_FIELD_STRING;
- break;
- case lttng_ust_type_array:
- if (lttng_ust_get_type_array(event_field->type)->encoding == lttng_ust_string_encoding_none)
- list_entry->field.type = LTTNG_UST_ABI_FIELD_OTHER;
- else
- list_entry->field.type = LTTNG_UST_ABI_FIELD_STRING;
- break;
- case lttng_ust_type_sequence:
- if (lttng_ust_get_type_sequence(event_field->type)->encoding == lttng_ust_string_encoding_none)
- list_entry->field.type = LTTNG_UST_ABI_FIELD_OTHER;
- else
- list_entry->field.type = LTTNG_UST_ABI_FIELD_STRING;
- break;
- case lttng_ust_type_float:
- list_entry->field.type = LTTNG_UST_ABI_FIELD_FLOAT;
- break;
- case lttng_ust_type_enum:
- list_entry->field.type = LTTNG_UST_ABI_FIELD_ENUM;
- break;
- default:
- list_entry->field.type = LTTNG_UST_ABI_FIELD_OTHER;
- }
- if (!event_desc->loglevel) {
- list_entry->field.loglevel = TRACE_DEFAULT;
- } else {
- list_entry->field.loglevel = *(*event_desc->loglevel);
- }
- list_entry->field.nowrite = event_field->nowrite;
- }
- }
- }
- if (cds_list_empty(&list->head))
- list->iter = NULL;
- else
- list->iter =
- cds_list_first_entry(&list->head,
- struct tp_field_list_entry, head);
- return 0;
-
-err_nomem:
- lttng_probes_prune_field_list(list);
- return -ENOMEM;
-}
-
-/*
- * Return current iteration position, advance internal iterator to next.
- * Return NULL if end of list.
- */
-struct lttng_ust_abi_field_iter *
- lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list)
-{
- struct tp_field_list_entry *entry;
-
- if (!list->iter)
- return NULL;
- entry = list->iter;
- if (entry->head.next == &list->head)
- list->iter = NULL;
- else
- list->iter = cds_list_entry(entry->head.next,
- struct tp_field_list_entry, head);
- return &entry->field;
-}
projects / lttng-ust.git / blobdiff