From 18fc2df4831d888a48ba0fa1d3c52c6b618addf8 Mon Sep 17 00:00:00 2001
From: ckolivas <kernel@kolivas.org>
Date: Mon, 11 Mar 2013 13:23:51 +1100
Subject: [PATCH] Implement cg_lock write biased rwlocks.

---
 miner.h | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/miner.h b/miner.h
index bd243051..fadbf093 100644
--- a/miner.h
+++ b/miner.h
@@ -696,6 +696,44 @@ static inline void rwlock_init(pthread_rwlock_t *lock)
 		quit(1, "Failed to pthread_rwlock_init");
 }
 
+/* cgminer locks, a write biased variant of rwlocks */
+struct cglock {
+	pthread_mutex_t mutex;
+	pthread_rwlock_t rwlock;
+};
+
+typedef struct cglock cglock_t;
+
+static inline void cglock_init(cglock_t *lock)
+{
+	mutex_init(&lock->mutex);
+	rwlock_init(&lock->rwlock);
+}
+
+static inline void cg_rlock(cglock_t *lock)
+{
+	mutex_lock(&lock->mutex);
+	rd_lock(&lock->rwlock);
+	mutex_unlock(&lock->mutex);
+}
+
+static inline void cg_wlock(cglock_t *lock)
+{
+	mutex_lock(&lock->mutex);
+	wr_lock(&lock->rwlock);
+	mutex_unlock(&lock->mutex);
+}
+
+static inline void cg_runlock(cglock_t *lock)
+{
+	rd_unlock(&lock->rwlock);
+}
+
+static inline void cg_wunlock(cglock_t *lock)
+{
+	wr_unlock(&lock->rwlock);
+}
+
 struct pool;
 
 extern bool opt_protocol;