[KE]

- KxAcquireSpinLock: check for already owned lock only on debug builds, fix check in inner loop, don't call Kii386SpinOnSpinLock inside the inner loop, but instead of it, simplify the code
- stubplement Kii386SpinOnSpinLock in C

svn path=/branches/ros-amd64-bringup/; revision=44886

reactos/ntoskrnl/include/internal/ke_x.h

@@ -101,6 +101,10 @@ KeGetPreviousMode(VOID)
     }                                                                       \
 }
 
+VOID
+NTAPI
+Kii386SpinOnSpinLock(PKSPIN_LOCK SpinLock, ULONG Flags);
+
 #ifndef CONFIG_SMP
 //
 // Spinlock Acquire at IRQL >= DISPATCH_LEVEL
@@ -310,44 +314,34 @@ FORCEINLINE
 VOID
 KxAcquireSpinLock(IN PKSPIN_LOCK SpinLock)
 {
+#ifdef DBG
     /* Make sure that we don't own the lock already */
     if (((KSPIN_LOCK)KeGetCurrentThread() | 1) == *SpinLock)
     {
         /* We do, bugcheck! */
         KeBugCheckEx(SPIN_LOCK_ALREADY_OWNED, (ULONG_PTR)SpinLock, 0, 0, 0);
     }
+#endif
 
-    /* Start acquire loop */
-    for (;;)
+    /* Try to acquire the lock */
+    while (InterlockedBitTestAndSet((PLONG)SpinLock, 0))
     {
-        /* Try to acquire it */
-        if (InterlockedBitTestAndSet((PLONG)SpinLock, 0))
-        {
-            /* Value changed... wait until it's unlocked */
-            while (*(volatile KSPIN_LOCK *)SpinLock == 1)
-            {
-#if DBG
-                /* On debug builds, we use a much slower but useful routine */
-                //Kii386SpinOnSpinLock(SpinLock, 5);
-
-                /* FIXME: Do normal yield for now */
-                YieldProcessor();
+#if defined(_M_IX86) && defined(DBG)
+        /* On x86 debug builds, we use a much slower but useful routine */
+        Kii386SpinOnSpinLock(SpinLock, 5);
 #else
-                /* Otherwise, just yield and keep looping */
-                YieldProcessor();
-#endif
-            }
-        }
-        else
+        /* It's locked... spin until it's unlocked */
+        while (*(volatile KSPIN_LOCK *)SpinLock & 1)
         {
-#if DBG
-            /* On debug builds, we OR in the KTHREAD */
-            *SpinLock = (KSPIN_LOCK)KeGetCurrentThread() | 1;
-#endif
-            /* All is well, break out */
-            break;
+                /* Yield and keep looping */
+                YieldProcessor();
         }
+#endif
     }
+#ifdef DBG
+    /* On debug builds, we OR in the KTHREAD */
+    *SpinLock = (KSPIN_LOCK)KeGetCurrentThread() | 1;
+#endif
 }
 
 //

reactos/ntoskrnl/ke/i386/trap.s

@@ -2828,31 +2828,3 @@ _KeSynchronizeExecution@12:
     ret 12
 .endfunc
 
-/*++
- * Kii386SpinOnSpinLock 
- *
- *     FILLMEIN
- *
- * Params:
- *     SpinLock - FILLMEIN
- *
- *     Flags - FILLMEIN
- *
- * Returns:
- *     None.
- *
- * Remarks:
- *     FILLMEIN
- *
- *--*/
-.globl _Kii386SpinOnSpinLock@8
-.func Kii386SpinOnSpinLock@8
-_Kii386SpinOnSpinLock@8:
-
-#ifdef CONFIG_SMP
-    /* FIXME: TODO */
-    int 3
-#endif
-
-    ret 8
-.endfunc

reactos/ntoskrnl/ke/spinlock.c

@@ -454,3 +454,22 @@ KeTestSpinLock(IN PKSPIN_LOCK SpinLock)
     /* Spinlock appears to be free */
     return TRUE;
 }
+
+#ifdef _M_IX86
+VOID
+NTAPI
+Kii386SpinOnSpinLock(PKSPIN_LOCK SpinLock, ULONG Flags)
+{
+    // FIXME: Handle flags
+    UNREFERENCED_PARAMETER(Flags);
+
+    /* Spin until it's unlocked */
+    while (*(volatile KSPIN_LOCK *)SpinLock & 1)
+    {
+        // FIXME: Check for timeout
+
+        /* Yield and keep looping */
+        YieldProcessor();
+    }
+}
+#endif