[RFC patch 32/41] LTTng filter

[Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>]

[-- Attachment #1: lttng-filter.patch --]
[-- Type: text/plain, Size: 4128 bytes --]

Filter module providing the filter/ directory entry.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
---
 include/linux/ltt-tracer.h |    2 +
 ltt/Kconfig                |    3 ++
 ltt/Makefile               |    1 
 ltt/ltt-filter.c           |   66 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 72 insertions(+)

Index: linux-2.6-lttng/ltt/Makefile
===================================================================
--- linux-2.6-lttng.orig/ltt/Makefile	2009-03-05 16:09:53.000000000 -0500
+++ linux-2.6-lttng/ltt/Makefile	2009-03-05 16:10:10.000000000 -0500
@@ -13,3 +13,4 @@ obj-$(CONFIG_LTT_STATEDUMP)		+= ltt-stat
 obj-$(CONFIG_LTT_FAST_SERIALIZE)	+= ltt-type-serializer.o
 obj-$(CONFIG_LTT_TRACE_CONTROL)		+= ltt-trace-control.o
 obj-$(CONFIG_LTT_USERSPACE_EVENT)	+= ltt-userspace-event.o
+obj-$(CONFIG_LTT_FILTER)		+= ltt-filter.o
Index: linux-2.6-lttng/ltt/ltt-filter.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6-lttng/ltt/ltt-filter.c	2009-03-05 16:09:59.000000000 -0500
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2008 Mathieu Desnoyers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/ltt-tracer.h>
+#include <linux/mutex.h>
+
+#define LTT_FILTER_DIR	"filter"
+
+/*
+ * Protects the ltt_filter_dir allocation.
+ */
+static DEFINE_MUTEX(ltt_filter_mutex);
+
+static struct dentry *ltt_filter_dir;
+
+struct dentry *get_filter_root(void)
+{
+	struct dentry *ltt_root_dentry;
+
+	mutex_lock(&ltt_filter_mutex);
+	if (!ltt_filter_dir) {
+		ltt_root_dentry = get_ltt_root();
+		if (!ltt_root_dentry)
+			goto err_no_root;
+
+		ltt_filter_dir = debugfs_create_dir(LTT_FILTER_DIR,
+						    ltt_root_dentry);
+		if (!ltt_filter_dir)
+			printk(KERN_ERR
+				"ltt_filter_init: failed to create dir %s\n",
+				LTT_FILTER_DIR);
+	}
+err_no_root:
+	mutex_unlock(&ltt_filter_mutex);
+	return ltt_filter_dir;
+}
+EXPORT_SYMBOL_GPL(get_filter_root);
+
+static void __exit ltt_filter_exit(void)
+{
+	debugfs_remove(ltt_filter_dir);
+}
+
+module_exit(ltt_filter_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>");
+MODULE_DESCRIPTION("Linux Trace Toolkit Filter");
Index: linux-2.6-lttng/include/linux/ltt-tracer.h
===================================================================
--- linux-2.6-lttng.orig/include/linux/ltt-tracer.h	2009-03-05 16:08:41.000000000 -0500
+++ linux-2.6-lttng/include/linux/ltt-tracer.h	2009-03-05 16:09:59.000000000 -0500
@@ -648,6 +648,8 @@ enum ltt_filter_control_msg {
 extern int ltt_filter_control(enum ltt_filter_control_msg msg,
 		const char *trace_name);
 
+extern struct dentry *get_filter_root(void);
+
 void ltt_write_trace_header(struct ltt_trace_struct *trace,
 		struct ltt_subbuffer_header *header);
 extern void ltt_buffer_destroy(struct ltt_channel_struct *ltt_chan);
Index: linux-2.6-lttng/ltt/Kconfig
===================================================================
--- linux-2.6-lttng.orig/ltt/Kconfig	2009-03-05 16:09:41.000000000 -0500
+++ linux-2.6-lttng/ltt/Kconfig	2009-03-05 16:09:59.000000000 -0500
@@ -28,6 +28,9 @@ menuconfig LTT
 
 if LTT
 
+config LTT_FILTER
+	tristate
+
 config LTT_RELAY_ALLOC
 	def_bool n
 

-- 
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68