From 3a054d37c1f5323462bd77f55be02c5b0d764611 Mon Sep 17 00:00:00 2001
From: Aliaksey Kandratsenka <alk@tut.by>
Date: Mon, 28 Sep 2015 15:40:15 -0700
Subject: dropped unused SpinLockWait function

---
 src/base/spinlock.cc          |  2 +-
 src/base/spinlock_internal.cc | 20 --------------------
 src/base/spinlock_internal.h  | 14 --------------
 3 files changed, 1 insertion(+), 35 deletions(-)

diff --git a/src/base/spinlock.cc b/src/base/spinlock.cc
index 2021fec..088785f 100644
--- a/src/base/spinlock.cc
+++ b/src/base/spinlock.cc
@@ -114,7 +114,7 @@ void SpinLock::SlowLock() {
                                                         kSpinLockSleeper);
       if (lock_value == kSpinLockHeld) {
         // Successfully transitioned to kSpinLockSleeper.  Pass
-        // kSpinLockSleeper to the SpinLockWait routine to properly indicate
+        // kSpinLockSleeper to the SpinLockDelay routine to properly indicate
         // the last lock_value observed.
         lock_value = kSpinLockSleeper;
       } else if (lock_value == kSpinLockFree) {
diff --git a/src/base/spinlock_internal.cc b/src/base/spinlock_internal.cc
index e090f9b..d962971 100644
--- a/src/base/spinlock_internal.cc
+++ b/src/base/spinlock_internal.cc
@@ -57,26 +57,6 @@ namespace base { namespace internal { static int SuggestedDelayNS(int loop); }}
 namespace base {
 namespace internal {
 
-// See spinlock_internal.h for spec.
-int32 SpinLockWait(volatile Atomic32 *w, int n,
-                   const SpinLockWaitTransition trans[]) {
-  int32 v;
-  bool done = false;
-  for (int loop = 0; !done; loop++) {
-    v = base::subtle::Acquire_Load(w);
-    int i;
-    for (i = 0; i != n && v != trans[i].from; i++) {
-    }
-    if (i == n) {
-      SpinLockDelay(w, v, loop);     // no matching transition
-    } else if (trans[i].to == v ||   // null transition
-               base::subtle::Acquire_CompareAndSwap(w, v, trans[i].to) == v) {
-      done = trans[i].done;
-    }
-  }
-  return v;
-}
-
 // Return a suggested delay in nanoseconds for iteration number "loop"
 static int SuggestedDelayNS(int loop) {
   // Weak pseudo-random number generator to get some spread between threads
diff --git a/src/base/spinlock_internal.h b/src/base/spinlock_internal.h
index 4d3c17f..aa47e67 100644
--- a/src/base/spinlock_internal.h
+++ b/src/base/spinlock_internal.h
@@ -43,20 +43,6 @@
 namespace base {
 namespace internal {
 
-// SpinLockWait() waits until it can perform one of several transitions from
-// "from" to "to".  It returns when it performs a transition where done==true.
-struct SpinLockWaitTransition {
-  int32 from;
-  int32 to;
-  bool done;
-};
-
-// Wait until *w can transition from trans[i].from to trans[i].to for some i
-// satisfying 0<=i<n && trans[i].done, atomically make the transition,
-// then return the old value of *w.   Make any other atomic tranistions
-// where !trans[i].done, but continue waiting.
-int32 SpinLockWait(volatile Atomic32 *w, int n,
-                   const SpinLockWaitTransition trans[]);
 void SpinLockWake(volatile Atomic32 *w, bool all);
 void SpinLockDelay(volatile Atomic32 *w, int32 value, int loop);
 
-- 
cgit v1.2.1