* \brief Short Spinlock structure
*/
struct sShortSpinlock {
+ #if STACKED_LOCKS == 2
+ volatile void *Lock; //!< Lock value
+ #else
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;
-
- // Save interrupt state
- __ASM__ ("pushf;\n\tpop %%rax" : "=a"(Lock->IF));
- Lock->IF &= 0x200;
-
- // Stop interrupts
- __ASM__ ("cli");
+ #endif
- // Wait for another CPU to release
- while(v)
- __ASM__("xchgl %%eax, (%%rdi)":"=a"(v):"a"(1),"D"(&Lock->Lock));
-}
-/**
- * \brief Release a short lock
- * \param Lock Lock pointer
- */
-static inline void SHORTREL(struct sShortSpinlock *Lock) {
- Lock->Lock = 0;
- #if 0 // Which is faster?, meh the test is simpler
- __ASM__ ("pushf;\n\tor %0, (%%rsp);\n\tpopf" : : "a"(Lock->IF));
- #else
- if(Lock->IF) __ASM__ ("sti");
+ #if LOCK_DISABLE_INTS
+ int IF; //!< Interrupt state on call to SHORTLOCK
+ #endif
+ #if STACKED_LOCKS
+ int Depth;
#endif
-}
+};
+
+// === FUNCTIONS ===
+extern int IS_LOCKED(struct sShortSpinlock *Lock);
+extern int CPU_HAS_LOCK(struct sShortSpinlock *Lock);
+extern void SHORTLOCK(struct sShortSpinlock *Lock);
+extern void SHORTREL(struct sShortSpinlock *Lock);
#endif