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struct spinlock_t {
	uint32t volatile lock;
	uint32t flags;
};

static inline void spinAcquire(struct spinlock_t *spinlock) {
	asm volatile("movl $0x1,%%edx\n\t"
				"1:\t testl $0x1,(%%eax)\n\t"
				"jne 1b\n\t"
				"xchg (%%eax),%%edx\n\t"
				"testl $0x1,%%edx\n\t"
				"jne 1b\n\t"
				"pushfl\n\t"
				"popl %[output]\n\t"
				"cli"
				:[output] "=q"(spinlock->flags)
				:"a"(spinlock)
				:"%edx");
}

static inline void spinRelease(struct spinlock_t *spinlock) {
	//look if ints were enabled or disabled
	if(likely((spinlock->flags & 0x200) != 0)) {
		spinlock->lock= 0;
		
		asm volatile("sti");
	} else {
		spinlock->lock= 0;
	}
}

Code: Select all

static struct smpMsg_t *freeList;
static struct spinlock_t freeLock;

struct smpMsg_t *smpAllocMsg() {
	struct smpMsg_t *msg;
	
	do {		
		spinAcquire(&freeLock);
		
		if(likely(freeList)) {
			msg= freeList;
			freeList= msg->next;
			
			spinRelease(&freeLock);
			
			return msg;
		}
		
		spinRelease(&freeLock);
		
		while(likely(freeList == 0))
			asm volatile("pause");
	} while(1);
}

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void smpSendMsgBroadcast(uint32t code, uint32t data1, uint32t data2, uint32t data3) {
	if(likely(msgsAllowed)) {
		struct smpMsg_t *msg= smpAllocMsg();
		struct APIC_Regs_t *apic= (struct APIC_Regs_t *)APIC_ADDR_VIRT;
		
		msg->refCount= numCpus - 1;
		msg->code= code;
		msg->data1= data1;
		msg->data2= data2;
		msg->data3= data3;
		
		spinAcquire(&msgLock);
		
		serviceMsg= msg;
		
		while(unlikely(apic->icr1[0] & APIC_DELIVERY_STS))
			asm volatile("pause");

		apic->icr2[0]= 0;
		apic->icr1[0]= APIC_SERVICE_INT | APIC_DEL_MODE_FIXED | APIC_DEST_SHORT_ALL_EXC_SELF;
		
//		printf("msg send...");
		
		while(unlikely(apic->icr1[0] & APIC_DELIVERY_STS))
			asm volatile("pause");
			
//		printf("waiting...");
		
		while(likely(msg->refCount > 0))
			asm volatile("pause");
			
		printf("ok\n");
		
		serviceMsg= 0;
		
		spinRelease(&msgLock);
		
		smpFreeMsg(msg);
	}
}

Code: Select all

static struct smpMsg_t * volatile freeList