From dda6fe101bced0a4b071af5badd3f4cf50d4866f Mon Sep 17 00:00:00 2001 From: John Hodge Date: Sun, 15 Jan 2012 17:49:02 +0800 Subject: [PATCH] Kernel/x86 - Fixed bug in SHORTLOCK that caused locks to always succeed --- Kernel/arch/x86/lib.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/Kernel/arch/x86/lib.c b/Kernel/arch/x86/lib.c index ecc575c1..a3050fe1 100644 --- 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)); -- 2.20.1