scheduling usermode processes & code refactoring

4 files changed, 116 insertions, 98 deletions

diff --git a/kernel/src/apic/apic.c b/kernel/src/apic/apic.c
index ad3ccec..0316b5c 100644
--- a/kernel/src/apic/apic.c
+++ b/kernel/src/apic/apic.c
@@ -22,84 +22,88 @@ uint8_t curr_cpu_apic_id()
 			 0xFF);
 }
 
+void clear_apic_errors()
+{
+	*((__volatile__ uint32_t *)(lapic_addr + 0x280)) = 0;
+}
+
+void wait_for_delivery()
+{
+	do {
+		__asm__ __volatile__("pause" : : : "memory");
+	} while (*((__volatile__ uint32_t *)(uint64_t)(lapic_addr + 0x300)) &
+		 (1 << 12));
+}
+
+void select_ap(uint32_t apic_id)
+{
+	*((__volatile__ uint32_t *)(lapic_addr + 0x310)) =
+		(*((__volatile__ uint32_t *)(lapic_addr + 0x310)) &
+		 0x00ffffff) |
+		apic_id;
+}
+
+void send_init_ipi(uint32_t apic_id)
+{
+	clear_apic_errors();
+	select_ap(apic_id);
+
+	/* trigger INIT IPI */
+	*((__volatile__ uint32_t *)(lapic_addr + 0x300)) =
+		(*((__volatile__ uint32_t *)(lapic_addr + 0x300)) &
+		 0xfff00000) |
+		0x00C500;
+
+	wait_for_delivery();
+	select_ap(apic_id);
+
+	/* deassert */
+	*((__volatile__ uint32_t *)(lapic_addr + 0x300)) =
+		(*((__volatile__ uint32_t *)(lapic_addr + 0x300)) &
+		 0xfff00000) |
+		0x008500;
+
+	wait_for_delivery();
+}
+
+void send_sipi(uint32_t apic_id)
+{
+	clear_apic_errors();
+	select_ap(apic_id);
+
+	/* trigger STARTUP IPI for 0800:0000 */
+	*((__volatile__ uint32_t *)(lapic_addr + 0x300)) =
+		(*((__volatile__ uint32_t *)(lapic_addr + 0x300)) &
+		 0xfff0f800) |
+		0x000608;
+
+	/* wait 200 usec */
+	wait(1);
+	wait_for_delivery();
+}
+
 void init_ap_cpus()
 {
-	uint8_t bspid = curr_cpu_apic_id();
+	uint8_t bspid;
+	size_t i;
+	size_t j;
 
 	init_mutex(&cnt_lock);
 	map_addr(lapic_addr, lapic_addr, FLAG_PRESENT);
 
-	size_t i;
-	size_t j;
+	bspid = curr_cpu_apic_id();
+
 	for (i = 0; i < numcores; i++) {
 		/* do not start BSP, that's already running this code */
 		if (cpu_apic_ids[i] == bspid)
 			continue;
 
-		/* send INIT IPI */
-
-		/* clear APIC errors */
-		*((__volatile__ uint32_t *)(lapic_addr + 0x280)) = 0;
-		/* select AP */
-		*((__volatile__ uint32_t *)(lapic_addr + 0x310)) =
-			(*((__volatile__ uint32_t *)(lapic_addr + 0x310)) &
-			 0x00ffffff) |
-			((uint32_t)cpu_apic_ids[i] << 24);
-		/* trigger INIT IPI */
-		*((__volatile__ uint32_t *)(lapic_addr + 0x300)) =
-			(*((__volatile__ uint32_t *)(lapic_addr + 0x300)) &
-			 0xfff00000) |
-			0x00C500;
-		/* wait for delivery */
-		do {
-			__asm__ __volatile__("pause" : : : "memory");
-		} while (*((__volatile__ uint32_t *)(uint64_t)(lapic_addr +
-							       0x300)) &
-			 (1 << 12));
-		/* select AP */
-		*((__volatile__ uint32_t *)(lapic_addr + 0x310)) =
-			(*((__volatile__ uint32_t *)(lapic_addr + 0x310)) &
-			 0x00ffffff) |
-			((uint32_t)cpu_apic_ids[i] << 24);
-		/* deassert */
-		*((__volatile__ uint32_t *)(lapic_addr + 0x300)) =
-			(*((__volatile__ uint32_t *)(lapic_addr + 0x300)) &
-			 0xfff00000) |
-			0x008500;
-		/* wait for delivery */
-		do {
-			__asm__ __volatile__("pause" : : : "memory");
-		} while (*((__volatile__ uint32_t *)(uint64_t)(lapic_addr +
-							       0x300)) &
-			 (1 << 12));
-		/* wait 10 msec */
-		wait(10);
+		send_init_ipi((uint32_t)cpu_apic_ids[i] << 24);
 
-		/* send STARTUP IPI (twice) */
+		wait(10);
 
 		for (j = 0; j < 2; j++) {
-			/* clear APIC errors */
-			*((__volatile__ uint32_t *)(lapic_addr + 0x280)) = 0;
-			/* select AP */
-			*((__volatile__ uint32_t *)(lapic_addr + 0x310)) =
-				(*((__volatile__ uint32_t *)(lapic_addr +
-							     0x310)) &
-				 0x00ffffff) |
-				((uint32_t)cpu_apic_ids[i] << 24);
-			/* trigger STARTUP IPI for 0800:0000 */
-			*((__volatile__ uint32_t *)(lapic_addr + 0x300)) =
-				(*((__volatile__ uint32_t *)(lapic_addr +
-							     0x300)) &
-				 0xfff0f800) |
-				0x000608;
-			/* wait 200 usec */
-			wait(1);
-			/* wait for delivery */
-			do {
-				__asm__ __volatile__("pause" : : : "memory");
-			} while (*((__volatile__ uint32_t
-					    *)(uint64_t)(lapic_addr + 0x300)) &
-				 (1 << 12));
+			send_sipi((uint32_t)cpu_apic_ids[i] << 24);
 		}
 	}
 
diff --git a/kernel/src/apic/ioapic.c b/kernel/src/apic/ioapic.c
index 7fe005b..1e20486 100644
--- a/kernel/src/apic/ioapic.c
+++ b/kernel/src/apic/ioapic.c
@@ -30,14 +30,16 @@ void ioapic_set_irq(uint8_t irq, uint64_t apic_id, uint8_t vector)
 {
 	const uint32_t low_index = (uint32_t)0x10 + irq * 2;
 	const uint32_t high_index = (uint32_t)0x10 + irq * 2 + 1;
+	uint32_t high;
+	uint32_t low;
 
-	uint32_t high = ioapic_read((uint8_t)high_index);
+	high = ioapic_read((uint8_t)high_index);
 	/* set APIC ID */
 	high &= (uint32_t)~0xff000000;
 	high |= (uint32_t)apic_id << 24;
 	ioapic_write((uint8_t)high_index, high);
 
-	uint32_t low = ioapic_read((uint8_t)low_index);
+	low = ioapic_read((uint8_t)low_index);
 
 	/* unmask the IRQ */
 	low &= (uint32_t) ~(1 << 16);
@@ -57,10 +59,12 @@ void ioapic_set_irq(uint8_t irq, uint64_t apic_id, uint8_t vector)
 
 void apic_remap_interrupts()
 {
+	uint8_t bspid;
+
 	map_addr(ioapic_addr, ioapic_addr, FLAG_PRESENT);
 	map_addr(lapic_addr, lapic_addr, FLAG_PRESENT);
 
-	uint8_t bspid = curr_cpu_apic_id();
+	bspid = curr_cpu_apic_id();
 
 	/* irq is 2 because of gsi remap */
 	ioapic_set_irq(0x2, bspid, 0x20); /* timer */
diff --git a/kernel/src/apic/madt.c b/kernel/src/apic/madt.c
index 2ddf90f..d45b1cb 100644
--- a/kernel/src/apic/madt.c
+++ b/kernel/src/apic/madt.c
@@ -66,25 +66,28 @@ void madt_parse_lapic_addr_ovr(uint64_t *addr)
 void parse_madt()
 {
 	uint64_t *madt_addr = find_sys_table_addr("APIC");
+	struct MADT *madt;
+	size_t curr_size;
+	uint8_t type;
+	uint8_t len;
 
 	if (madt_addr == NULL) {
 		printf("MADT NOT FOUND\n");
 		return;
 	}
 
-	struct MADT *madt = (struct MADT *)kalloc(sizeof(struct MADT));
+	madt = (struct MADT *)kalloc(sizeof(struct MADT));
 	memcpy(madt, madt_addr, sizeof(struct MADT));
 	lapic_addr = madt->lapic_addr;
 
-	size_t curr_size;
 	for (curr_size = sizeof(struct MADT); curr_size < madt->h.Length;) {
 		struct MADT_type_header *m = (struct MADT_type_header *)kalloc(
 			sizeof(struct MADT_type_header));
 		memcpy(m,
 		       (uint64_t *)((uint64_t)madt_addr + (uint64_t)curr_size),
 		       sizeof(struct MADT_type_header));
-		uint8_t type = m->type;
-		uint8_t len = m->len;
+		type = m->type;
+		len = m->len;
 		kfree(m);
 
 		switch (type) {
diff --git a/kernel/src/apic/rsdp.c b/kernel/src/apic/rsdp.c
index 6a1505f..fa16816 100644
--- a/kernel/src/apic/rsdp.c
+++ b/kernel/src/apic/rsdp.c
@@ -6,14 +6,17 @@
 
 uint64_t *find_rsdp()
 {
-	map_addr(0x0, 0x0, FLAG_PRESENT);
 	const char *rsdp_cs = "RSD PTR ";
 	uint64_t i;
 	size_t j;
+	char *x;
+	uint8_t ind;
+
+	map_addr(0x0, 0x0, FLAG_PRESENT);
 
 	for (i = 0x10; i < 0x100000; i += 0x10) {
-		char *x = (char *)i;
-		uint8_t ind = 1;
+		x = (char *)i;
+		ind = 1;
 		for (j = 0; j < strlen(rsdp_cs); j++) {
 			if (rsdp_cs[j] != x[j]) {
 				ind = 0;
@@ -30,33 +33,35 @@ uint64_t *find_rsdp()
 void list_sys_tables(void)
 {
 	uint64_t *rsdp = find_rsdp();
+	struct RSDP_descriptor *rsdp_desc;
+	struct ACPI_header *rsdt;
+	uint32_t entries;
+	size_t i;
+	size_t j;
+	uint32_t na_addr;
+	uint32_t addr;
+	struct ACPI_header *t;
 
 	if (rsdp == NULL) {
 		printf("RSDP NOT FOUND\n");
 		return;
 	}
 
-	struct RSDP_descriptor *rsdp_desc = (struct RSDP_descriptor *)rsdp;
+	rsdp_desc = (struct RSDP_descriptor *)rsdp;
 	map_addr(rsdp_desc->RsdtAddress, rsdp_desc->RsdtAddress, FLAG_PRESENT);
 
-	struct ACPI_header *rsdt =
-		(struct ACPI_header *)kalloc(sizeof(struct ACPI_header));
+	rsdt = (struct ACPI_header *)kalloc(sizeof(struct ACPI_header));
 	memcpy(rsdt, (uint64_t *)(uint64_t)rsdp_desc->RsdtAddress,
 	       sizeof(struct ACPI_header));
 
-	uint32_t entries =
-		(rsdt->Length - (uint32_t)sizeof(struct ACPI_header)) / 4;
-	size_t i;
-	size_t j;
+	entries = (rsdt->Length - (uint32_t)sizeof(struct ACPI_header)) / 4;
 	for (i = 0; i < entries; i++) {
-		uint32_t na_addr = (uint32_t)rsdp_desc->RsdtAddress +
-				   (uint32_t)sizeof(struct ACPI_header) +
-				   (uint32_t)i * 4;
-		uint32_t addr;
+		na_addr = (uint32_t)rsdp_desc->RsdtAddress +
+			  (uint32_t)sizeof(struct ACPI_header) +
+			  (uint32_t)i * 4;
 		memcpy(&addr, (uint64_t *)(uint64_t)na_addr, 4);
 
-		struct ACPI_header *t = (struct ACPI_header *)kalloc(
-			sizeof(struct ACPI_header));
+		t = (struct ACPI_header *)kalloc(sizeof(struct ACPI_header));
 		memcpy(t, (uint64_t *)(uint64_t)addr,
 		       sizeof(struct ACPI_header));
 
@@ -75,38 +80,40 @@ void list_sys_tables(void)
 uint64_t *find_sys_table_addr(const char *signature)
 {
 	uint64_t *rsdp = find_rsdp();
+	struct RSDP_descriptor *rsdp_desc;
+	struct ACPI_header *rsdt;
+	uint32_t entries;
+	size_t i;
+	size_t j;
+	uint32_t addr;
+	struct ACPI_header *t;
+	uint8_t ind = 1;
 
 	if (rsdp == NULL) {
 		printf("RSDP NOT FOUND\n");
 		return NULL;
 	}
 
-	struct RSDP_descriptor *rsdp_desc = (struct RSDP_descriptor *)rsdp;
+	rsdp_desc = (struct RSDP_descriptor *)rsdp;
 	map_addr(rsdp_desc->RsdtAddress, rsdp_desc->RsdtAddress, FLAG_PRESENT);
 
-	struct ACPI_header *rsdt =
-		(struct ACPI_header *)kalloc(sizeof(struct ACPI_header));
+	rsdt = (struct ACPI_header *)kalloc(sizeof(struct ACPI_header));
 	memcpy(rsdt, (uint64_t *)(uint64_t)rsdp_desc->RsdtAddress,
 	       sizeof(struct ACPI_header));
 
-	uint32_t entries =
-		(rsdt->Length - (uint32_t)sizeof(struct ACPI_header)) / 4;
+	entries = (rsdt->Length - (uint32_t)sizeof(struct ACPI_header)) / 4;
 
-	size_t i;
-	size_t j;
 	for (i = 0; i < entries; i++) {
 		uint32_t na_addr = (uint32_t)rsdp_desc->RsdtAddress +
 				   (uint32_t)sizeof(struct ACPI_header) +
 				   (uint32_t)i * 4;
-		uint32_t addr;
 		memcpy(&addr, (uint64_t *)(uint64_t)na_addr, 4);
 
-		struct ACPI_header *t = (struct ACPI_header *)kalloc(
-			sizeof(struct ACPI_header));
+		t = (struct ACPI_header *)kalloc(sizeof(struct ACPI_header));
 		memcpy(t, (uint64_t *)(uint64_t)addr,
 		       sizeof(struct ACPI_header));
 
-		int ind = 1;
+		ind = 1;
 		for (j = 0; j < 4; j++) {
 			if (t->Signature[j] != signature[j])
 				ind = 0;