Changeset fe32163 in mainline for kernel/arch/ia32/src/smp/smp.c

Timestamp:

2010-06-29T00:08:48Z (14 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

c19aa612

Parents:

9a21f9d

Message:

improve support for inactive CPUs
major revision of MADT and MPS parsing code
limit the number of active CPUs on ia32 and amd64 to 8 (actually the APIC ID of all active CPUs must be in the range 0 .. 7 to avoid tripping on an assertion in APIC code)
fix off-by-one bug in MADT parsing code (missing the last entry)

File:

• kernel/arch/ia32/src/smp/smp.c (modified) (9 diffs)

kernel/arch/ia32/src/smp/smp.c

@@ -62 +62 @@
 void smp_init(void)
 {
-        uintptr_t l_apic_address, io_apic_address;
-
+        uintptr_t l_apic_address;
+        uintptr_t io_apic_address;
+        
         if (acpi_madt) {
                 acpi_madt_parse();
                 ops = &madt_config_operations;
         }
+        
         if (config.cpu_count == 1) {
                 mps_init();
                 ops = &mps_config_operations;
         }
-
+        
         l_apic_address = (uintptr_t) frame_alloc(ONE_FRAME,
             FRAME_ATOMIC | FRAME_KA);
         if (!l_apic_address)
                 panic("Cannot allocate address for l_apic.");
-
+        
         io_apic_address = (uintptr_t) frame_alloc(ONE_FRAME,
             FRAME_ATOMIC | FRAME_KA);
         if (!io_apic_address)
                 panic("Cannot allocate address for io_apic.");
-
+        
         if (config.cpu_count > 1) {
                 page_table_lock(AS_KERNEL, true);
@@ -90 +92 @@
                     (uintptr_t) io_apic, PAGE_NOT_CACHEABLE | PAGE_WRITE);
                 page_table_unlock(AS_KERNEL, true);
-                                  
+                
                 l_apic = (uint32_t *) l_apic_address;
                 io_apic = (uint32_t *) io_apic_address;
@@ -108 +110 @@
         
         ASSERT(ops != NULL);
-
+        
         /*
          * We need to access data in frame 0.
          * We boldly make use of kernel address space mapping.
          */
-
+        
         /*
          * Set the warm-reset vector to the real-mode address of 4K-aligned ap_boot()
          */
         *((uint16_t *) (PA2KA(0x467 + 0))) =
-            (uint16_t) (((uintptr_t) ap_boot) >> 4);    /* segment */
-        *((uint16_t *) (PA2KA(0x467 + 2))) = 0;         /* offset */
+            (uint16_t) (((uintptr_t) ap_boot) >> 4);  /* segment */
+        *((uint16_t *) (PA2KA(0x467 + 2))) = 0;       /* offset */
         
         /*
@@ -125 +127 @@
          * BIOS will not do the POST after the INIT signal.
          */
-        pio_write_8((ioport8_t *)0x70, 0xf);
-        pio_write_8((ioport8_t *)0x71, 0xa);
-
+        pio_write_8((ioport8_t *) 0x70, 0xf);
+        pio_write_8((ioport8_t *) 0x71, 0xa);
+        
         pic_disable_irqs(0xffff);
         apic_init();
         
         uint8_t apic = l_apic_id();
-
-        for (i = 0; i < ops->cpu_count(); i++) {
-                descriptor_t *gdt_new;
-                
+        
+        for (i = 0; i < config.cpu_count; i++) {
                 /*
                  * Skip processors marked unusable.
@@ -141 +141 @@
                 if (!ops->cpu_enabled(i))
                         continue;
-
+                
                 /*
                  * The bootstrap processor is already up.
@@ -147 +147 @@
                 if (ops->cpu_bootstrap(i))
                         continue;
-
+                
                 if (ops->cpu_apic_id(i) == apic) {
                         printf("%s: bad processor entry #%u, will not send IPI "
@@ -162 +162 @@
                  * the memory subsystem
                  */
-                gdt_new = (descriptor_t *) malloc(GDT_ITEMS *
-                    sizeof(descriptor_t), FRAME_ATOMIC);
+                descriptor_t *gdt_new =
+                    (descriptor_t *) malloc(GDT_ITEMS * sizeof(descriptor_t),
+                    FRAME_ATOMIC);
                 if (!gdt_new)
                         panic("Cannot allocate memory for GDT.");
-
+                
                 memcpy(gdt_new, gdt, GDT_ITEMS * sizeof(descriptor_t));
                 memsetb(&gdt_new[TSS_DES], sizeof(descriptor_t), 0);
@@ -172 +173 @@
                 protected_ap_gdtr.base = KA2PA((uintptr_t) gdt_new);
                 gdtr.base = (uintptr_t) gdt_new;
-
+                
                 if (l_apic_send_init_ipi(ops->cpu_apic_id(i))) {
                         /*
@@ -181 +182 @@
                         if (waitq_sleep_timeout(&ap_completion_wq, 1000000,
                             SYNCH_FLAGS_NONE) == ESYNCH_TIMEOUT) {
-                                unsigned int cpu = (config.cpu_active > i) ?
-                                    config.cpu_active : i;
                                 printf("%s: waiting for cpu%u (APIC ID = %d) "
-                                    "timed out\n", __FUNCTION__, cpu,
+                                    "timed out\n", __FUNCTION__, i,
                                     ops->cpu_apic_id(i));
                         }