Simplify requirements on interrupts during initialization

Don't involve the pmap module directly, as there could be others. Make
the cpu module completely responsible for synchronizing all processors
on kernel entry so that interrupts can be explicitely enabled there.

1 files changed, 21 insertions, 9 deletions

diff --git a/arch/x86/machine/cpu.c b/arch/x86/machine/cpu.c
index 82af7c30..b0567943 100644
--- a/arch/x86/machine/cpu.c
+++ b/arch/x86/machine/cpu.c
@@ -70,7 +70,12 @@ struct cpu cpu_array[MAX_CPUS];
 
 /*
  * Number of configured processors.
+ *
+ * The boot version is used until all processors are configured, since some
+ * modules depend on cpu_count() to adjust their behaviour when several
+ * processors are present.
  */
+static unsigned int cpu_boot_array_size;
 unsigned int cpu_array_size;
 
 /*
@@ -298,6 +303,7 @@ cpu_setup(void)
         cpu_array[i].state = CPU_STATE_OFF;
     }
 
+    cpu_boot_array_size = 1;
     cpu_array_size = 1;
     cpu_init(&cpu_array[0]);
 }
@@ -341,13 +347,13 @@ cpu_mp_register_lapic(unsigned int apic_id, int is_bsp)
         return;
     }
 
-    if (cpu_array_size == ARRAY_SIZE(cpu_array)) {
+    if (cpu_boot_array_size == ARRAY_SIZE(cpu_array)) {
         printk("cpu: ignoring processor beyond id %u\n", MAX_CPUS - 1);
         return;
     }
 
-    cpu_array[cpu_array_size].apic_id = apic_id;
-    cpu_array_size++;
+    cpu_array[cpu_boot_array_size].apic_id = apic_id;
+    cpu_boot_array_size++;
 }
 
 static void __init
@@ -360,7 +366,7 @@ cpu_mp_start_aps(void)
     size_t map_size;
     unsigned int i;
 
-    if (cpu_array_size == 1)
+    if (cpu_boot_array_size == 1)
         return;
 
     assert(BOOT_MP_TRAMPOLINE_ADDR < BIOSMEM_BASE);
@@ -396,7 +402,7 @@ cpu_mp_start_aps(void)
      * Preallocate stacks now, as the kernel mappings shouldn't change while
      * the APs are bootstrapping.
      */
-    for (i = 1; i < cpu_array_size; i++) {
+    for (i = 1; i < cpu_boot_array_size; i++) {
         cpu = &cpu_array[i];
         cpu->boot_stack = vm_kmem_alloc(BOOT_STACK_SIZE);
 
@@ -405,7 +411,7 @@ cpu_mp_start_aps(void)
     }
 
     /* Perform the "Universal Start-up Algorithm" */
-    for (i = 1; i < cpu_array_size; i++) {
+    for (i = 1; i < cpu_boot_array_size; i++) {
         cpu = &cpu_array[i];
 
         boot_ap_id = i;
@@ -424,6 +430,8 @@ cpu_mp_start_aps(void)
         while (cpu->state == CPU_STATE_OFF)
             cpu_pause();
     }
+
+    cpu_array_size = cpu_boot_array_size;
 }
 
 static void __init
@@ -437,8 +445,6 @@ cpu_mp_setup(void)
 {
     acpimp_setup();
     cpu_mp_start_aps();
-    cpu_intr_enable();
-    pmap_mp_setup();
     cpu_mp_info();
 }
 
@@ -448,5 +454,11 @@ cpu_ap_setup(void)
     cpu_init(&cpu_array[boot_ap_id]);
     cpu_check(cpu_current());
     lapic_ap_setup();
-    cpu_intr_enable();
+}
+
+void __init
+cpu_ap_sync(void)
+{
+    while (cpu_count() == 1)
+        cpu_pause();
 }