X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=lttng-context-ppid.c;h=28c97b58ff77f70208c0d19f409966b19667e885;hb=79150a4903b5f31695fcd1d9655555ba6dc4bfa4;hp=aaa334bc0a3fda482c6404781041955d98af6aad;hpb=a90917c3f8c4ed79117f1caa333b29a2108084ec;p=lttng-modules.git

diff --git a/lttng-context-ppid.c b/lttng-context-ppid.c
index aaa334bc..28c97b58 100644
--- a/lttng-context-ppid.c
+++ b/lttng-context-ppid.c
@@ -1,10 +1,23 @@
 /*
- * (C) Copyright	2009-2011 -
- * 		Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * lttng-context-ppid.c
  *
  * LTTng PPID context.
  *
- * Dual LGPL v2.1/GPL v2 license.
+ * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <linux/module.h>
@@ -33,6 +46,13 @@ void ppid_record(struct lttng_ctx_field *field,
 {
 	pid_t ppid;
 
+	/*
+	 * 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();
 	ppid = task_tgid_nr(current->real_parent);
 	rcu_read_unlock();
@@ -40,6 +60,26 @@ void ppid_record(struct lttng_ctx_field *field,
 	chan->ops->event_write(ctx, &ppid, sizeof(ppid));
 }
 
+static
+void ppid_get_value(struct lttng_ctx_field *field,
+		struct lttng_probe_ctx *lttng_probe_ctx,
+		union lttng_ctx_value *value)
+{
+	pid_t ppid;
+
+	/*
+	 * 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();
+	ppid = task_tgid_nr(current->real_parent);
+	rcu_read_unlock();
+	value->s64 = ppid;
+}
+
 int lttng_add_ppid_to_ctx(struct lttng_ctx **ctx)
 {
 	struct lttng_ctx_field *field;
@@ -55,12 +95,14 @@ int lttng_add_ppid_to_ctx(struct lttng_ctx **ctx)
 	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 = ppid_get_size;
 	field->record = ppid_record;
+	field->get_value = ppid_get_value;
+	lttng_context_update(*ctx);
 	wrapper_vmalloc_sync_all();
 	return 0;
 }
@@ -69,3 +111,7 @@ EXPORT_SYMBOL_GPL(lttng_add_ppid_to_ctx);
 MODULE_LICENSE("GPL and additional rights");
 MODULE_AUTHOR("Mathieu Desnoyers");
 MODULE_DESCRIPTION("Linux Trace Toolkit PPID Context");
+MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
+	__stringify(LTTNG_MODULES_MINOR_VERSION) "."
+	__stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
+	LTTNG_MODULES_EXTRAVERSION);