pid_t vppid;
/*
- * nsproxy can be NULL when scheduled out of exit.
+ * current nsproxy can be NULL when scheduled out of exit. pid_vnr uses
+ * the current thread nsproxy to perform the lookup.
*/
+
+ /*
+ * TODO: when we eventually add RCU subsystem instrumentation,
+ * taking the rcu read lock here will trigger RCU tracing
+ * recursively. We should modify the kernel synchronization so
+ * it synchronizes both for RCU and RCU sched, and rely on
+ * rcu_read_lock_sched_notrace.
+ */
+
rcu_read_lock();
parent = rcu_dereference(current->real_parent);
- if (!parent->nsproxy)
+ if (!current->nsproxy)
vppid = 0;
else
vppid = task_tgid_vnr(parent);
chan->ops->event_write(ctx, &vppid, sizeof(vppid));
}
+static
+void vppid_get_value(struct lttng_ctx_field *field,
+ struct lttng_probe_ctx *lttng_probe_ctx,
+ union lttng_ctx_value *value)
+{
+ struct task_struct *parent;
+ pid_t vppid;
+
+ /*
+ * current nsproxy can be NULL when scheduled out of exit. pid_vnr uses
+ * the current thread nsproxy to perform the lookup.
+ */
+
+ /*
+ * TODO: when we eventually add RCU subsystem instrumentation,
+ * taking the rcu read lock here will trigger RCU tracing
+ * recursively. We should modify the kernel synchronization so
+ * it synchronizes both for RCU and RCU sched, and rely on
+ * rcu_read_lock_sched_notrace.
+ */
+
+ rcu_read_lock();
+ parent = rcu_dereference(current->real_parent);
+ if (!current->nsproxy)
+ vppid = 0;
+ else
+ vppid = task_tgid_vnr(parent);
+ rcu_read_unlock();
+ value->s64 = vppid;
+}
+
int lttng_add_vppid_to_ctx(struct lttng_ctx **ctx)
{
struct lttng_ctx_field *field;
field->event_field.type.atype = atype_integer;
field->event_field.type.u.basic.integer.size = sizeof(pid_t) * CHAR_BIT;
field->event_field.type.u.basic.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT;
- field->event_field.type.u.basic.integer.signedness = is_signed_type(pid_t);
+ field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(pid_t);
field->event_field.type.u.basic.integer.reverse_byte_order = 0;
field->event_field.type.u.basic.integer.base = 10;
field->event_field.type.u.basic.integer.encoding = lttng_encode_none;
field->get_size = vppid_get_size;
field->record = vppid_record;
+ field->get_value = vppid_get_value;
+ lttng_context_update(*ctx);
wrapper_vmalloc_sync_all();
return 0;
}
MODULE_LICENSE("GPL and additional rights");
MODULE_AUTHOR("Mathieu Desnoyers");
MODULE_DESCRIPTION("Linux Trace Toolkit vPPID Context");
+MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
+ __stringify(LTTNG_MODULES_MINOR_VERSION) "."
+ __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
+ LTTNG_MODULES_EXTRAVERSION);