#include <sys/types.h>
#include <common/common.h>
+#include <common/hashtable/utils.h>
#include <common/trace-chunk.h>
#include <common/kernel-ctl/kernel-ctl.h>
#include <common/kernel-ctl/kernel-ioctl.h>
#include <lttng/lttng-error.h>
#include <lttng/tracker.h>
+#include <lttng/userspace-probe.h>
+#include <lttng/userspace-probe-internal.h>
+#include <lttng/condition/event-rule.h>
+#include <lttng/condition/event-rule-internal.h>
+#include <lttng/event-rule/event-rule.h>
+#include <lttng/event-rule/event-rule-internal.h>
+#include <lttng/event-rule/uprobe-internal.h>
+
#include "lttng-sessiond.h"
#include "lttng-syscall.h"
+#include "condition-internal.h"
#include "consumer.h"
#include "kernel.h"
#include "kernel-consumer.h"
#include "rotate.h"
#include "modprobe.h"
#include "tracker.h"
+#include "notification-thread-commands.h"
/*
* Key used to reference a channel between the sessiond and the consumer. This
static const char *module_proc_lttng = "/proc/lttng";
static int kernel_tracer_fd = -1;
+static int kernel_tracer_event_notifier_group_fd = -1;
+static int kernel_tracer_event_notifier_group_notification_fd = -1;
+static struct cds_lfht *kernel_token_to_event_notifier_rule_ht;
-#include <lttng/userspace-probe.h>
-#include <lttng/userspace-probe-internal.h>
/*
* Add context on a kernel channel.
*
return -1;
}
+/*
+ * Create a kernel event notifier group, register it to the kernel tracer and
+ * add it to the kernel session.
+ */
+static int kernel_create_event_notifier_group(int *event_notifier_group_fd)
+{
+ int ret;
+ int local_fd = -1;
+
+ assert(event_notifier_group_fd);
+
+ /* Kernel event notifier group creation. */
+ ret = kernctl_create_event_notifier_group(kernel_tracer_fd);
+ if (ret < 0) {
+ PERROR("Failed to create kernel event notifier group");
+ ret = -1;
+ goto error;
+ }
+
+ local_fd = ret;
+
+ /* Prevent fd duplication after execlp(). */
+ ret = fcntl(local_fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ PERROR("Failed to set FD_CLOEXEC on kernel event notifier group file descriptor: fd = %d",
+ local_fd);
+ goto error;
+ }
+
+ DBG("Created kernel event notifier group: fd = %d", local_fd);
+ *event_notifier_group_fd = local_fd;
+ local_fd = -1;
+ ret = 0;
+error:
+ if (local_fd >= 0) {
+ ret = close(local_fd);
+ if (ret) {
+ PERROR("Failed to close kernel event notifier group file descriptor: fd = %d",
+ local_fd);
+ }
+ }
+
+ return ret;
+}
+
/*
* Compute the offset of the instrumentation byte in the binary based on the
* function probe location using the ELF lookup method.
return ret;
}
+/*
+ * Extract the offsets of the instrumentation point for the different look-up
+ * methods.
+ */
+static int userspace_probe_event_rule_add_callsites(
+ const struct lttng_event_rule *rule,
+ const struct lttng_credentials *creds,
+ int fd)
+{
+ int ret;
+ enum lttng_event_rule_status status;
+ enum lttng_event_rule_type event_rule_type;
+ const struct lttng_userspace_probe_location *location = NULL;
+
+ assert(rule);
+ assert(creds);
+
+ event_rule_type = lttng_event_rule_get_type(rule);
+ assert(event_rule_type == LTTNG_EVENT_RULE_TYPE_UPROBE);
+
+ status = lttng_event_rule_uprobe_get_location(rule, &location);
+ if (status != LTTNG_EVENT_RULE_STATUS_OK || !location) {
+ ret = -1;
+ goto end;
+ }
+
+ ret = userspace_probe_add_callsite(location,
+ lttng_credentials_get_uid(creds),
+ lttng_credentials_get_gid(creds), fd);
+ if (ret) {
+ WARN("Failed to add callsite to user space probe object: fd = %d",
+ fd);
+ }
+
+end:
+ return ret;
+}
+
/*
* Create a kernel event, enable it to the kernel tracer and add it to the
* channel event list of the kernel session.
return ret;
}
+/*
+ * Disable a kernel event notifier.
+ */
+static
+int kernel_disable_event_notifier_rule(struct ltt_kernel_event_notifier_rule *event)
+{
+ int ret;
+
+ assert(event);
+
+ rcu_read_lock();
+ cds_lfht_del(kernel_token_to_event_notifier_rule_ht, &event->ht_node);
+ rcu_read_unlock();
+
+ ret = kernctl_disable(event->fd);
+ if (ret < 0) {
+ switch (-ret) {
+ case EEXIST:
+ ret = LTTNG_ERR_KERN_EVENT_EXIST;
+ break;
+ default:
+ PERROR("Failed to disable kernel event notifier: fd = %d, token = %" PRIu64,
+ event->fd, event->token);
+ break;
+ }
+ goto error;
+ }
+
+ event->enabled = 0;
+ DBG("Disabled kernel event notifier: fd = %d, token = %" PRIu64,
+ event->fd, event->token);
+
+error:
+ return ret;
+}
+
static
struct process_attr_tracker *_kernel_get_process_attr_tracker(
struct ltt_kernel_session *session,
if (ret < 0) {
goto error_modules;
}
-
if (ret < 1) {
WARN("Kernel tracer does not support buffer monitoring. "
"The monitoring timer of channels in the kernel domain "
"will be set to 0 (disabled).");
}
- DBG("Kernel tracer fd %d", kernel_tracer_fd);
+ ret = kernel_supports_event_notifiers();
+ if (ret < 0) {
+ ERR("Failed to check for kernel tracer event notifier support");
+ goto error_modules;
+ }
+ ret = kernel_create_event_notifier_group(&kernel_tracer_event_notifier_group_fd);
+ if (ret < 0) {
+ /* This is not fatal. */
+ WARN("Failed to create kernel event notifier group");
+ kernel_tracer_event_notifier_group_fd = -1;
+ } else {
+ const enum lttng_error_code error_code_ret =
+ kernel_create_event_notifier_group_notification_fd(
+ &kernel_tracer_event_notifier_group_notification_fd);
+
+ if (error_code_ret != LTTNG_OK) {
+ goto error_modules;
+ }
+
+ kernel_token_to_event_notifier_rule_ht = cds_lfht_new(
+ DEFAULT_HT_SIZE, 1, 0,
+ CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING,
+ NULL);
+ if (!kernel_token_to_event_notifier_rule_ht) {
+ goto error_token_ht;
+ }
+ }
+
+ DBG("Kernel tracer initialized: kernel tracer fd = %d, event notifier group fd = %d, event notifier group notification fd = %d",
+ kernel_tracer_fd, kernel_tracer_event_notifier_group_fd,
+ kernel_tracer_event_notifier_group_notification_fd);
ret = syscall_init_table(kernel_tracer_fd);
if (ret < 0) {
ERR("Unable to populate syscall table. Syscall tracing won't "
"work for this session daemon.");
}
+
return 0;
error_version:
modprobe_remove_lttng_control();
ret = close(kernel_tracer_fd);
if (ret) {
- PERROR("close");
+ PERROR("Failed to close kernel tracer file descriptor: fd = %d",
+ kernel_tracer_fd);
}
kernel_tracer_fd = -1;
return LTTNG_ERR_KERN_VERSION;
+
+error_token_ht:
+ ret = close(kernel_tracer_event_notifier_group_notification_fd);
+ if (ret) {
+ PERROR("Failed to close kernel tracer event notifier group notification file descriptor: fd = %d",
+ kernel_tracer_event_notifier_group_notification_fd);
+ }
+
error_modules:
+ ret = close(kernel_tracer_event_notifier_group_fd);
+ if (ret) {
+ PERROR("Failed to close kernel tracer event notifier group file descriptor: fd = %d",
+ kernel_tracer_event_notifier_group_fd);
+ }
+
ret = close(kernel_tracer_fd);
if (ret) {
- PERROR("close");
+ PERROR("Failed to close kernel tracer file descriptor: fd = %d",
+ kernel_tracer_fd);
}
error_open:
void cleanup_kernel_tracer(void)
{
int ret;
+ struct cds_lfht_iter iter;
+ struct ltt_kernel_event_notifier_rule *rule = NULL;
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry(kernel_token_to_event_notifier_rule_ht, &iter, rule, ht_node) {
+ kernel_disable_event_notifier_rule(rule);
+ trace_kernel_destroy_event_notifier_rule(rule);
+ }
+ rcu_read_unlock();
+
+ DBG2("Closing kernel event notifier group notification file descriptor");
+ if (kernel_tracer_event_notifier_group_notification_fd >= 0) {
+ ret = notification_thread_command_remove_tracer_event_source(
+ notification_thread_handle,
+ kernel_tracer_event_notifier_group_notification_fd);
+ if (ret != LTTNG_OK) {
+ ERR("Failed to remove kernel event notifier notification from notification thread");
+ }
+
+ ret = close(kernel_tracer_event_notifier_group_notification_fd);
+ if (ret) {
+ PERROR("Failed to close kernel event notifier group notification file descriptor: fd = %d",
+ kernel_tracer_event_notifier_group_notification_fd);
+ }
+
+ kernel_tracer_event_notifier_group_notification_fd = -1;
+ }
+
+ if (kernel_token_to_event_notifier_rule_ht) {
+ ret = cds_lfht_destroy(kernel_token_to_event_notifier_rule_ht, NULL);
+ assert(ret == 0);
+ }
+
+ DBG2("Closing kernel event notifier group file descriptor");
+ if (kernel_tracer_event_notifier_group_fd >= 0) {
+ ret = close(kernel_tracer_event_notifier_group_fd);
+ if (ret) {
+ PERROR("Failed to close kernel event notifier group file descriptor: fd = %d",
+ kernel_tracer_event_notifier_group_fd);
+ }
+
+ kernel_tracer_event_notifier_group_fd = -1;
+ }
DBG2("Closing kernel fd");
if (kernel_tracer_fd >= 0) {
ret = close(kernel_tracer_fd);
if (ret) {
- PERROR("close");
+ PERROR("Failed to close kernel tracer file descriptor: fd = %d",
+ kernel_tracer_fd);
}
+
kernel_tracer_fd = -1;
}
+
DBG("Unloading kernel modules");
modprobe_remove_lttng_all();
free(syscall_table);
rcu_read_unlock();
return status;
}
+
+enum lttng_error_code kernel_create_event_notifier_group_notification_fd(
+ int *event_notifier_group_notification_fd)
+{
+ int local_fd = -1, ret;
+ enum lttng_error_code error_code_ret;
+
+ assert(event_notifier_group_notification_fd);
+
+ ret = kernctl_create_event_notifier_group_notification_fd(
+ kernel_tracer_event_notifier_group_fd);
+ if (ret < 0) {
+ PERROR("Failed to create kernel event notifier group notification file descriptor");
+ error_code_ret = LTTNG_ERR_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD;
+ goto error;
+ }
+
+ local_fd = ret;
+
+ /* Prevent fd duplication after execlp(). */
+ ret = fcntl(local_fd, F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ PERROR("Failed to set FD_CLOEXEC on kernel event notifier group notification file descriptor: fd = %d",
+ local_fd);
+ error_code_ret = LTTNG_ERR_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD;
+ goto error;
+ }
+
+ DBG("Created kernel notifier group notification file descriptor: fd = %d",
+ local_fd);
+ error_code_ret = LTTNG_OK;
+ *event_notifier_group_notification_fd = local_fd;
+ local_fd = -1;
+
+error:
+ if (local_fd >= 0) {
+ ret = close(local_fd);
+ if (ret) {
+ PERROR("Failed to close kernel event notifier group notification file descriptor: fd = %d",
+ local_fd);
+ }
+ }
+
+ return error_code_ret;
+}
+
+enum lttng_error_code kernel_destroy_event_notifier_group_notification_fd(
+ int event_notifier_group_notification_fd)
+{
+ enum lttng_error_code ret_code = LTTNG_OK;
+
+ DBG("Closing event notifier group notification file descriptor: fd = %d",
+ event_notifier_group_notification_fd);
+ if (event_notifier_group_notification_fd >= 0) {
+ const int ret = close(event_notifier_group_notification_fd);
+ if (ret) {
+ PERROR("Failed to close event notifier group notification file descriptor: fd = %d",
+ event_notifier_group_notification_fd);
+ }
+ }
+
+ return ret_code;
+}
+
+static
+unsigned long hash_trigger(const struct lttng_trigger *trigger)
+{
+ const struct lttng_condition *condition =
+ lttng_trigger_get_const_condition(trigger);
+
+ return lttng_condition_hash(condition);
+}
+
+static
+int match_trigger(struct cds_lfht_node *node, const void *key)
+{
+ const struct ltt_kernel_event_notifier_rule *event_notifier_rule;
+ const struct lttng_trigger *trigger = key;
+
+ event_notifier_rule = caa_container_of(node,
+ const struct ltt_kernel_event_notifier_rule, ht_node);
+
+ return lttng_trigger_is_equal(trigger, event_notifier_rule->trigger);
+}
+
+static enum lttng_error_code kernel_create_event_notifier_rule(
+ struct lttng_trigger *trigger,
+ const struct lttng_credentials *creds, uint64_t token)
+{
+ int err, fd, ret = 0;
+ enum lttng_error_code error_code_ret;
+ enum lttng_condition_status condition_status;
+ enum lttng_condition_type condition_type;
+ enum lttng_event_rule_type event_rule_type;
+ struct ltt_kernel_event_notifier_rule *event_notifier_rule;
+ struct lttng_kernel_event_notifier kernel_event_notifier = {};
+ const struct lttng_condition *condition = NULL;
+ const struct lttng_event_rule *event_rule = NULL;
+
+ assert(trigger);
+
+ condition = lttng_trigger_get_const_condition(trigger);
+ assert(condition);
+
+ condition_type = lttng_condition_get_type(condition);
+ assert(condition_type == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT);
+
+ /* Does not acquire a reference. */
+ condition_status = lttng_condition_event_rule_get_rule(
+ condition, &event_rule);
+ assert(condition_status == LTTNG_CONDITION_STATUS_OK);
+ assert(event_rule);
+
+ event_rule_type = lttng_event_rule_get_type(event_rule);
+ assert(event_rule_type != LTTNG_EVENT_RULE_TYPE_UNKNOWN);
+
+ error_code_ret = trace_kernel_create_event_notifier_rule(trigger, token,
+ &event_notifier_rule);
+ if (error_code_ret != LTTNG_OK) {
+ goto error;
+ }
+
+ error_code_ret = trace_kernel_init_event_notifier_from_event_rule(
+ event_rule, &kernel_event_notifier);
+ if (error_code_ret != LTTNG_OK) {
+ goto error;
+ }
+
+ kernel_event_notifier.event.token = event_notifier_rule->token;
+
+ fd = kernctl_create_event_notifier(
+ kernel_tracer_event_notifier_group_fd,
+ &kernel_event_notifier);
+ if (fd < 0) {
+ switch (-fd) {
+ case EEXIST:
+ error_code_ret = LTTNG_ERR_KERN_EVENT_EXIST;
+ break;
+ case ENOSYS:
+ WARN("Failed to create kernel event notifier: not notifier type not implemented");
+ error_code_ret = LTTNG_ERR_KERN_EVENT_ENOSYS;
+ break;
+ case ENOENT:
+ WARN("Failed to create kernel event notifier: not found: name = '%s'",
+ kernel_event_notifier.event.name);
+ error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL;
+ break;
+ default:
+ PERROR("Failed to create kernel event notifier: error code = %d, name = '%s'",
+ fd, kernel_event_notifier.event.name);
+ error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL;
+ }
+ goto free_event;
+ }
+
+ event_notifier_rule->fd = fd;
+ /* Prevent fd duplication after execlp(). */
+ err = fcntl(event_notifier_rule->fd, F_SETFD, FD_CLOEXEC);
+ if (err < 0) {
+ PERROR("Failed to set FD_CLOEXEC on kernel event notifier file descriptor: fd = %d",
+ fd);
+ error_code_ret = LTTNG_ERR_FATAL;
+ goto set_cloexec_error;
+ }
+
+ if (event_notifier_rule->filter) {
+ err = kernctl_filter(event_notifier_rule->fd, event_notifier_rule->filter);
+ if (err < 0) {
+ switch (-err) {
+ case ENOMEM:
+ error_code_ret = LTTNG_ERR_FILTER_NOMEM;
+ break;
+ default:
+ error_code_ret = LTTNG_ERR_FILTER_INVAL;
+ break;
+ }
+ goto filter_error;
+ }
+ }
+
+ if (lttng_event_rule_get_type(event_rule) ==
+ LTTNG_EVENT_RULE_TYPE_UPROBE) {
+ ret = userspace_probe_event_rule_add_callsites(
+ event_rule, creds, event_notifier_rule->fd);
+ if (ret) {
+ error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL;
+ goto add_callsite_error;
+ }
+ }
+
+ err = kernctl_enable(event_notifier_rule->fd);
+ if (err < 0) {
+ switch (-err) {
+ case EEXIST:
+ error_code_ret = LTTNG_ERR_KERN_EVENT_EXIST;
+ break;
+ default:
+ PERROR("enable kernel event notifier");
+ error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL;
+ break;
+ }
+ goto enable_error;
+ }
+
+ /* Add trigger to kernel token mapping in the hash table. */
+ rcu_read_lock();
+ cds_lfht_add(kernel_token_to_event_notifier_rule_ht, hash_trigger(trigger),
+ &event_notifier_rule->ht_node);
+ rcu_read_unlock();
+
+ DBG("Created kernel event notifier: name = '%s', fd = %d",
+ kernel_event_notifier.event.name,
+ event_notifier_rule->fd);
+
+ return LTTNG_OK;
+
+add_callsite_error:
+enable_error:
+set_cloexec_error:
+filter_error:
+ {
+ const int close_ret = close(event_notifier_rule->fd);
+
+ if (close_ret) {
+ PERROR("Failed to close kernel event notifier file descriptor: fd = %d",
+ event_notifier_rule->fd);
+ }
+ }
+free_event:
+ free(event_notifier_rule);
+error:
+ return error_code_ret;
+}
+
+enum lttng_error_code kernel_register_event_notifier(
+ struct lttng_trigger *trigger,
+ const struct lttng_credentials *cmd_creds)
+{
+ enum lttng_error_code ret;
+ enum lttng_condition_status status;
+ enum lttng_domain_type domain_type;
+ const struct lttng_event_rule *event_rule;
+ const struct lttng_condition *const condition =
+ lttng_trigger_get_const_condition(trigger);
+ const uint64_t token = lttng_trigger_get_tracer_token(trigger);
+
+ assert(condition);
+
+ /* Does not acquire a reference to the event rule. */
+ status = lttng_condition_event_rule_get_rule(
+ condition, &event_rule);
+ assert(status == LTTNG_CONDITION_STATUS_OK);
+
+ domain_type = lttng_event_rule_get_domain_type(event_rule);
+ assert(domain_type == LTTNG_DOMAIN_KERNEL);
+
+ ret = kernel_create_event_notifier_rule(trigger, cmd_creds, token);
+ if (ret != LTTNG_OK) {
+ ERR("Failed to create kernel trigger");
+ }
+
+ return ret;
+}
+
+enum lttng_error_code kernel_unregister_event_notifier(
+ const struct lttng_trigger *trigger)
+{
+ struct ltt_kernel_event_notifier_rule *token_event_rule_element;
+ struct cds_lfht_node *node;
+ struct cds_lfht_iter iter;
+ enum lttng_error_code error_code_ret;
+ int ret;
+
+ rcu_read_lock();
+
+ cds_lfht_lookup(kernel_token_to_event_notifier_rule_ht,
+ hash_trigger(trigger), match_trigger, trigger, &iter);
+
+ node = cds_lfht_iter_get_node(&iter);
+ if (!node) {
+ error_code_ret = LTTNG_ERR_TRIGGER_NOT_FOUND;
+ goto error;
+ }
+
+ token_event_rule_element = caa_container_of(node,
+ struct ltt_kernel_event_notifier_rule, ht_node);
+
+ ret = kernel_disable_event_notifier_rule(token_event_rule_element);
+ if (ret) {
+ error_code_ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+
+ trace_kernel_destroy_event_notifier_rule(token_event_rule_element);
+ error_code_ret = LTTNG_OK;
+
+error:
+ rcu_read_unlock();
+
+ return error_code_ret;
+}
+
+int kernel_get_notification_fd(void)
+{
+ return kernel_tracer_event_notifier_group_notification_fd;
+}
#include <lttng/event.h>
#include <lttng/lttng-error.h>
+#include <lttng/kernel-probe.h>
#include <lttng/userspace-probe.h>
#include <lttng/userspace-probe-internal.h>
-
+#include <lttng/event-rule/event-rule.h>
+#include <lttng/event-rule/event-rule-internal.h>
+#include <lttng/event-rule/kprobe.h>
+#include <lttng/event-rule/kprobe-internal.h>
+#include <lttng/event-rule/syscall.h>
+#include <lttng/event-rule/syscall-internal.h>
+#include <lttng/event-rule/tracepoint.h>
+#include <lttng/event-rule/tracepoint-internal.h>
+#include <lttng/event-rule/uprobe-internal.h>
#include <common/common.h>
#include <common/defaults.h>
#include <common/trace-chunk.h>
*/
attr->instrumentation = LTTNG_KERNEL_UPROBE;
- /*
- * Only the elf lookup method is supported at the moment.
- */
lookup = lttng_userspace_probe_location_get_lookup_method(
location);
if (!lookup) {
return ret;
}
+/*
+ * Allocate and initialize a kernel token event rule.
+ *
+ * Return pointer to structure or NULL.
+ */
+enum lttng_error_code trace_kernel_create_event_notifier_rule(
+ struct lttng_trigger *trigger,
+ uint64_t token,
+ struct ltt_kernel_event_notifier_rule **event_notifier_rule)
+{
+ enum lttng_error_code ret = LTTNG_OK;
+ enum lttng_condition_type condition_type;
+ enum lttng_event_rule_type event_rule_type;
+ enum lttng_condition_status condition_status;
+ struct ltt_kernel_event_notifier_rule *local_kernel_token_event_rule;
+ const struct lttng_condition *condition = NULL;
+ const struct lttng_event_rule *event_rule = NULL;
+
+ assert(event_notifier_rule);
+
+ condition = lttng_trigger_get_condition(trigger);
+ assert(condition);
+
+ condition_type = lttng_condition_get_type(condition);
+ assert(condition_type == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT);
+
+ condition_status = lttng_condition_event_rule_get_rule(
+ condition, &event_rule);
+ assert(condition_status == LTTNG_CONDITION_STATUS_OK);
+ assert(event_rule);
+
+ event_rule_type = lttng_event_rule_get_type(event_rule);
+ assert(event_rule_type != LTTNG_EVENT_RULE_TYPE_UNKNOWN);
+
+ local_kernel_token_event_rule =
+ zmalloc(sizeof(struct ltt_kernel_event_notifier_rule));
+ if (local_kernel_token_event_rule == NULL) {
+ PERROR("Failed to allocate ltt_kernel_token_event_rule structure");
+ ret = LTTNG_ERR_NOMEM;
+ goto error;
+ }
+
+ local_kernel_token_event_rule->fd = -1;
+ local_kernel_token_event_rule->enabled = 1;
+ local_kernel_token_event_rule->token = token;
+
+ /* Get the reference of the event rule. */
+ lttng_trigger_get(trigger);
+
+ local_kernel_token_event_rule->trigger = trigger;
+ /* The event rule still owns the filter and bytecode. */
+ local_kernel_token_event_rule->filter =
+ lttng_event_rule_get_filter_bytecode(event_rule);
+
+ DBG3("Created kernel event notifier rule: token = %" PRIu64,
+ local_kernel_token_event_rule->token);
+error:
+ *event_notifier_rule = local_kernel_token_event_rule;
+ return ret;
+}
+
+/*
+ * Initialize a kernel trigger from an event rule.
+ */
+enum lttng_error_code trace_kernel_init_event_notifier_from_event_rule(
+ const struct lttng_event_rule *rule,
+ struct lttng_kernel_event_notifier *kernel_event_notifier)
+{
+ enum lttng_error_code ret;
+ const char *name;
+
+ switch (lttng_event_rule_get_type(rule)) {
+ case LTTNG_EVENT_RULE_TYPE_KPROBE:
+ {
+ uint64_t address = 0, offset = 0;
+ const char *symbol_name = NULL;
+ const struct lttng_kernel_probe_location *location = NULL;
+ enum lttng_kernel_probe_location_status k_status;
+ enum lttng_event_rule_status status;
+
+ status = lttng_event_rule_kprobe_get_location(rule, &location);
+ if (status != LTTNG_EVENT_RULE_STATUS_OK) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ switch (lttng_kernel_probe_location_get_type(location)) {
+ case LTTNG_KERNEL_PROBE_LOCATION_TYPE_ADDRESS:
+ {
+ k_status = lttng_kernel_probe_location_address_get_address(
+ location, &address);
+ assert(k_status == LTTNG_KERNEL_PROBE_LOCATION_STATUS_OK);
+ break;
+ }
+ case LTTNG_KERNEL_PROBE_LOCATION_TYPE_SYMBOL_OFFSET:
+ {
+ k_status = lttng_kernel_probe_location_symbol_get_offset(
+ location, &offset);
+ assert(k_status == LTTNG_KERNEL_PROBE_LOCATION_STATUS_OK);
+ symbol_name = lttng_kernel_probe_location_symbol_get_name(
+ location);
+ break;
+ }
+ default:
+ abort();
+ }
+
+ kernel_event_notifier->event.instrumentation = LTTNG_KERNEL_KPROBE;
+ kernel_event_notifier->event.u.kprobe.addr = address;
+ kernel_event_notifier->event.u.kprobe.offset = offset;
+ if (symbol_name) {
+ const int copy_ret = lttng_strncpy(
+ kernel_event_notifier->event.u.kprobe.symbol_name,
+ symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
+
+ if (copy_ret) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+ }
+
+ kernel_event_notifier->event.u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
+ status = lttng_event_rule_kprobe_get_name(rule, &name);
+ assert(status == LTTNG_EVENT_RULE_STATUS_OK);
+ ret = LTTNG_OK;
+ break;
+ }
+ case LTTNG_EVENT_RULE_TYPE_UPROBE:
+ {
+ const struct lttng_userspace_probe_location* location = NULL;
+ const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
+ enum lttng_event_rule_status status;
+
+ status = lttng_event_rule_uprobe_get_location(rule, &location);
+ if (status != LTTNG_EVENT_RULE_STATUS_OK) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ kernel_event_notifier->event.instrumentation = LTTNG_KERNEL_UPROBE;
+
+ lookup = lttng_userspace_probe_location_get_lookup_method(
+ location);
+ if (!lookup) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ /*
+ * From the kernel tracer's perspective, all userspace probe
+ * event types are all the same: a file and an offset.
+ */
+ switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) {
+ case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
+ /* Get the file descriptor on the target binary. */
+ kernel_event_notifier->event.u.uprobe.fd =
+ lttng_userspace_probe_location_function_get_binary_fd(location);
+
+ break;
+ case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
+ /* Get the file descriptor on the target binary. */
+ kernel_event_notifier->event.u.uprobe.fd =
+ lttng_userspace_probe_location_tracepoint_get_binary_fd(location);
+ break;
+ default:
+ abort();
+ }
+
+ status = lttng_event_rule_uprobe_get_name(rule, &name);
+ assert(status == LTTNG_EVENT_RULE_STATUS_OK);
+ ret = LTTNG_OK;
+ break;
+ }
+ case LTTNG_EVENT_RULE_TYPE_TRACEPOINT:
+ {
+ const enum lttng_domain_type domain =
+ lttng_event_rule_get_domain_type(rule);
+ const enum lttng_event_rule_status status =
+ lttng_event_rule_tracepoint_get_pattern(
+ rule, &name);
+
+ assert(domain == LTTNG_DOMAIN_KERNEL);
+ assert(status == LTTNG_EVENT_RULE_STATUS_OK);
+ kernel_event_notifier->event.instrumentation =
+ LTTNG_KERNEL_TRACEPOINT;
+
+ ret = LTTNG_OK;
+ break;
+ }
+ case LTTNG_EVENT_RULE_TYPE_SYSCALL:
+ {
+ const enum lttng_event_rule_status status =
+ lttng_event_rule_syscall_get_pattern(
+ rule, &name);
+
+ assert(status == LTTNG_EVENT_RULE_STATUS_OK);
+
+ kernel_event_notifier->event.instrumentation =
+ LTTNG_KERNEL_SYSCALL;
+ kernel_event_notifier->event.u.syscall.abi =
+ LTTNG_KERNEL_SYSCALL_ABI_ALL;
+ kernel_event_notifier->event.u.syscall.entryexit =
+ LTTNG_KERNEL_SYSCALL_ENTRY;
+ kernel_event_notifier->event.u.syscall.match =
+ LTTNG_KERNEL_SYSCALL_MATCH_NAME;
+ ret = LTTNG_OK;
+ break;
+ }
+ case LTTNG_EVENT_RULE_TYPE_KRETPROBE:
+ default:
+ abort();
+ break;
+ }
+
+ ret = lttng_strncpy(kernel_event_notifier->event.name, name,
+ LTTNG_KERNEL_SYM_NAME_LEN);
+ if (ret) {
+ ret = LTTNG_ERR_INVALID;
+ goto error;
+ }
+
+error:
+ return ret;
+}
/*
* Allocate and initialize a kernel metadata.
*
PERROR("close");
}
} else {
- DBG("[trace] Tearing down event (no associated fd)");
+ DBG("[trace] Tearing down event (no associated file descriptor)");
}
/* Remove from event list */
free(event);
}
+/*
+ * Cleanup kernel event structure.
+ */
+static void free_token_event_rule_rcu(struct rcu_head *rcu_node)
+{
+ struct ltt_kernel_event_notifier_rule *rule = caa_container_of(rcu_node,
+ struct ltt_kernel_event_notifier_rule, rcu_node);
+
+ free(rule);
+}
+
+void trace_kernel_destroy_event_notifier_rule(
+ struct ltt_kernel_event_notifier_rule *event)
+{
+ assert(event);
+
+ if (event->fd >= 0) {
+ const int ret = close(event->fd);
+
+ DBG("Closing kernel event notifier rule file descriptor: fd = %d",
+ event->fd);
+ if (ret) {
+ PERROR("Failed to close kernel event notifier file descriptor: fd = %d",
+ event->fd);
+ }
+ } else {
+ DBG("Destroying kernel event notifier rule (no associated file descriptor)");
+ }
+
+ lttng_trigger_put(event->trigger);
+ call_rcu(&event->rcu_node, free_token_event_rule_rcu);
+}
/*
* Cleanup kernel context structure.
*/
projects / lttng-tools.git / commitdiff
