# define PHYS_BITS 32
#endif
+#define __ASM__ __asm__ __volatile__
+
+// === Spinlocks ===
+/**
+ * \brief Short Spinlock structure
+ */
+struct sShortSpinlock {
+ volatile int Lock; //!< Lock value
+ int IF; //!< Interrupt state on call to SHORTLOCK
+};
+/**
+ * \brief Determine if a short spinlock is locked
+ * \param Lock Lock pointer
+ */
+static inline int IS_LOCKED(struct sShortSpinlock *Lock) {
+ return !!Lock->Lock;
+}
+/**
+ * \brief Acquire a Short Spinlock
+ * \param Lock Lock pointer
+ *
+ * This type of mutex should only be used for very short sections of code,
+ * or in places where a Mutex_* would be overkill, such as appending
+ * an element to linked list (usually two assignement lines in C)
+ *
+ * \note This type of lock halts interrupts, so ensure that no timing
+ * functions are called while it is held.
+ */
+static inline void SHORTLOCK(struct sShortSpinlock *Lock) {
+ int v = 1;
+ int IF;
+ // int val = GetCPUNum() + 1;
+
+ // Save interrupt state and clear interrupts
+ __ASM__ ("pushf;\n\tcli;\n\tpop %%eax" : "=a"(IF));
+ IF &= 0x200;
+
+ // Wait for another CPU to release
+ while(v)
+ __ASM__("xchgl %%ecx, (%%edi)":"=c"(v):"a"(1),"D"(&Lock->Lock));
+
+ Lock->IF = IF;
+}
+/**
+ * \brief Release a short lock
+ * \param Lock Lock pointer
+ */
+static inline void SHORTREL(struct sShortSpinlock *Lock) {
+ // Lock->IF can change anytime once Lock->Lock is zeroed
+ if(Lock->IF) {
+ Lock->Lock = 0;
+ __ASM__ ("sti");
+ }
+ else {
+ Lock->Lock = 0;
+ }
+}
+
// === MACROS ===
-typedef volatile int tSpinlock;
-#define IS_LOCKED(lockptr) (!!(*(tSpinlock*)lockptr))
-#define LOCK(lockptr) do {int v=1;\
- while(v)__asm__ __volatile__("lock xchgl %%eax, (%%edi)":"=a"(v):"a"(1),"D"(lockptr));}while(0)
-#define RELEASE(lockptr) __asm__ __volatile__("lock andl $0, (%%edi)"::"D"(lockptr));
+/**
+ * \brief Halt the CPU
+ */
#define HALT() __asm__ __volatile__ ("hlt")
+/**
+ * \brief Fire a magic breakpoint (bochs)
+ */
+#define MAGIC_BREAK() __asm__ __volatile__ ("xchg %bx, %bx")
// === TYPES ===
typedef unsigned int Uint; // Unsigned machine native integer