Kernel/x86 - Fixed bug in SHORTLOCK that caused locks to always succeed

diff --git a/Kernel/arch/x86/lib.c b/Kernel/arch/x86/lib.c
index ecc575c..a3050fe 100644 (file)
--- a/Kernel/arch/x86/lib.c
+++ b/Kernel/arch/x86/lib.c
@@ -17,8 +17,11 @@
 // === IMPRORTS ===
 #if TRACE_LOCKS
 extern struct sShortSpinlock   glDebug_Lock;
-extern struct sShortSpinlock   glThreadListLock;
+extern tMutex  glPhysAlloc;
+#define TRACE_LOCK_COND        (Lock != &glDebug_Lock && Lock != &glThreadListLock && Lock != &glPhysAlloc.Protector)
+//#define TRACE_LOCK_COND      (Lock != &glDebug_Lock && Lock != &glPhysAlloc.Protector)
 #endif
+
 extern int     GetCPUNum(void);
 
 // === PROTOTYPES ==
@@ -64,7 +67,6 @@ int CPU_HAS_LOCK(struct sShortSpinlock *Lock)
  */
 void SHORTLOCK(struct sShortSpinlock *Lock)
 {
-        int    v = 1;
         int    IF;
         int    cpu = GetCPUNum() + 1;
        
@@ -73,10 +75,10 @@ void SHORTLOCK(struct sShortSpinlock *Lock)
        IF &= 0x200;    // AND out all but the interrupt flag
        
        #if TRACE_LOCKS
-       if( Lock != &glDebug_Lock && Lock != &glThreadListLock )
+       if( TRACE_LOCK_COND )
        {
                //Log_Log("LOCK", "%p locked by %p", Lock, __builtin_return_address(0));
-               Debug("%p obtaining %p (Called by %p)", __builtin_return_address(0), Lock, __builtin_return_address(1));
+               Debug("%i %p obtaining %p (Called by %p)", cpu-1,  __builtin_return_address(0), Lock, __builtin_return_address(1));
        }
        #endif
        
@@ -84,20 +86,22 @@ void SHORTLOCK(struct sShortSpinlock *Lock)
        
        // Wait for another CPU to release
        __ASM__(
-               "1: lock cmpxchgl %2, (%3)\n\t"
-               "jnz 1b"
-               : "=a"(v)
-               : "a"(0), "r"(cpu), "r"(&Lock->Lock)
+               "1:\n\t"
+               "xor %%eax, %%eax;\n\t"
+               "lock cmpxchgl %0, (%1);\n\t"
+               "jnz 1b;\n\t"
+               :: "r"(cpu), "r"(&Lock->Lock)
+               : "eax" // EAX clobbered
                );
        
        Lock->IF = IF;
        
        #if TRACE_LOCKS
-       if( Lock != &glDebug_Lock && Lock != &glThreadListLock )
+       if( TRACE_LOCK_COND )
        {
                //Log_Log("LOCK", "%p locked by %p", Lock, __builtin_return_address(0));
-               //Debug("Lock %p locked by %p\t%p", Lock, __builtin_return_address(0), __builtin_return_address(1));
-               Debug("got it");
+               Debug("%i %p locked by %p\t%p", cpu-1, Lock, __builtin_return_address(0), __builtin_return_address(1));
+//             Debug("got it");
        }
        #endif
 }
@@ -108,7 +112,7 @@ void SHORTLOCK(struct sShortSpinlock *Lock)
 void SHORTREL(struct sShortSpinlock *Lock)
 {      
        #if TRACE_LOCKS
-       if( Lock != &glDebug_Lock && Lock != &glThreadListLock )
+       if( TRACE_LOCK_COND )
        {
                //Log_Log("LOCK", "%p released by %p", Lock, __builtin_return_address(0));
                Debug("Lock %p released by %p\t%p", Lock, __builtin_return_address(0), __builtin_return_address(1));