X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=include%2Flinux%2Fres_counter.h;h=fcb9884df6181827120dcb64efd7a2104fd157d7;hb=296c81d89f4f14269f7346f81442910158c0a83a;hp=dede0a2cfc45980a067e916ea1fabfeee273c7fb;hpb=28dbc4b6a01fb579a9441c7b81e3d3413dc452df;p=safe%2Fjmp%2Flinux-2.6

diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h
index dede0a2..fcb9884 100644
--- a/include/linux/res_counter.h
+++ b/include/linux/res_counter.h
@@ -9,7 +9,7 @@
  *
  * Author: Pavel Emelianov <xemul@openvz.org>
  *
- * See Documentation/controllers/resource_counter.txt for more
+ * See Documentation/cgroups/resource_counter.txt for more
  * info about what this counter is.
  */
 
@@ -35,6 +35,10 @@ struct res_counter {
 	 */
 	unsigned long long limit;
 	/*
+	 * the limit that usage can be exceed
+	 */
+	unsigned long long soft_limit;
+	/*
 	 * the number of unsuccessful attempts to consume the resource
 	 */
 	unsigned long long failcnt;
@@ -49,6 +53,8 @@ struct res_counter {
 	struct res_counter *parent;
 };
 
+#define RESOURCE_MAX (unsigned long long)LLONG_MAX
+
 /**
  * Helpers to interact with userspace
  * res_counter_read_u64() - returns the value of the specified member.
@@ -85,6 +91,7 @@ enum {
 	RES_MAX_USAGE,
 	RES_LIMIT,
 	RES_FAILCNT,
+	RES_SOFT_LIMIT,
 };
 
 /*
@@ -130,6 +137,36 @@ static inline bool res_counter_limit_check_locked(struct res_counter *cnt)
 	return false;
 }
 
+static inline bool res_counter_soft_limit_check_locked(struct res_counter *cnt)
+{
+	if (cnt->usage < cnt->soft_limit)
+		return true;
+
+	return false;
+}
+
+/**
+ * Get the difference between the usage and the soft limit
+ * @cnt: The counter
+ *
+ * Returns 0 if usage is less than or equal to soft limit
+ * The difference between usage and soft limit, otherwise.
+ */
+static inline unsigned long long
+res_counter_soft_limit_excess(struct res_counter *cnt)
+{
+	unsigned long long excess;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cnt->lock, flags);
+	if (cnt->usage <= cnt->soft_limit)
+		excess = 0;
+	else
+		excess = cnt->usage - cnt->soft_limit;
+	spin_unlock_irqrestore(&cnt->lock, flags);
+	return excess;
+}
+
 /*
  * Helper function to detect if the cgroup is within it's limit or
  * not. It's currently called from cgroup_rss_prepare()
@@ -145,6 +182,17 @@ static inline bool res_counter_check_under_limit(struct res_counter *cnt)
 	return ret;
 }
 
+static inline bool res_counter_check_under_soft_limit(struct res_counter *cnt)
+{
+	bool ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cnt->lock, flags);
+	ret = res_counter_soft_limit_check_locked(cnt);
+	spin_unlock_irqrestore(&cnt->lock, flags);
+	return ret;
+}
+
 static inline void res_counter_reset_max(struct res_counter *cnt)
 {
 	unsigned long flags;
@@ -178,4 +226,16 @@ static inline int res_counter_set_limit(struct res_counter *cnt,
 	return ret;
 }
 
+static inline int
+res_counter_set_soft_limit(struct res_counter *cnt,
+				unsigned long long soft_limit)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&cnt->lock, flags);
+	cnt->soft_limit = soft_limit;
+	spin_unlock_irqrestore(&cnt->lock, flags);
+	return 0;
+}
+
 #endif