[RFC] [PATCH 2.6.37-rc5-tip 17/20] 17: uprobes: filter chain

[Srikar Dronamraju <srikar@linux.vnet.ibm.com>]

Loops through the filters callbacks of currently registered
consumers to see if any consumer is interested in tracing this task.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
 kernel/uprobes.c |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/kernel/uprobes.c b/kernel/uprobes.c
index 93a3118..b0d323c 100644
--- a/kernel/uprobes.c
+++ b/kernel/uprobes.c
@@ -429,6 +429,24 @@ static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs)
 }
 
 /* Acquires uprobe->consumer_rwsem */
+static bool filter_chain(struct uprobe *uprobe, struct task_struct *t)
+{
+	struct uprobe_consumer *consumer;
+	bool ret = false;
+
+	down_read(&uprobe->consumer_rwsem);
+	for (consumer = uprobe->consumers; consumer;
+					consumer = consumer->next) {
+		if (!consumer->filter || consumer->filter(consumer, t)) {
+			ret = true;
+			break;
+		}
+	}
+	up_read(&uprobe->consumer_rwsem);
+	return ret;
+}
+
+/* Acquires uprobe->consumer_rwsem */
 static void add_consumer(struct uprobe *uprobe,
 				struct uprobe_consumer *consumer)
 {