x86 interrupt entry cleanup

diff -urN linux-2.5.1-pre2/arch/i386/kernel/entry.S linux/arch/i386/kernel/entry.S
@@ -45,6 +45,7 @@
 #include <linux/linkage.h>
 #include <asm/segment.h>
 #include <asm/smp.h>
+#include <asm/hw_irq.h>
 
 EBX		= 0x00
 ECX		= 0x04

@@ -132,6 +133,9 @@
 	movl $-8192, reg; \
 	andl %esp, reg
 
+/*
+ * Call gate entry points
+ */
 ENTRY(lcall7)
 	pushfl			# We get a different stack layout with call gates,
 	pushl %eax		# which has to be cleaned up later..

@@ -185,6 +189,8 @@
 	jmp	ret_from_sys_call
 
 /*
+ * System call entry point (int $0x80)
+ *
  * Return to user mode is not as complex as all this looks,
  * but we want the default path for a system call return to
  * go as quickly as possible which is why some of this is

@@ -244,8 +250,15 @@
 	movl $-ENOSYS,EAX(%esp)
 	jmp ret_from_sys_call
 
+/*
+ * Interrupt entry points.  orig_eax is used to
+ * specify which vector was called.
+ */
 	ALIGN
-ENTRY(ret_from_intr)
+common_interrupt:
+	SAVE_ALL
+	call SYMBOL_NAME(do_IRQ)
+ret_from_intr:
 	GET_CURRENT(%ebx)
 ret_from_exception:
 	movl EFLAGS(%esp),%eax		# mix EFLAGS and CS

@@ -254,11 +267,74 @@
 	jne ret_from_sys_call
 	jmp restore_all
 
+/*
+ * Build the entries and pointer table with some assembler black magic.
+ */
+.data
+ENTRY(interrupt)
+.previous
+
+irq_vector=0
+ENTRY(irq_entries_start)
+.rept NR_IRQS
+	ALIGN
+1:      pushl $irq_vector-256
+	jmp common_interrupt
+.data
+	.long 1b
+.previous
+	irq_vector=irq_vector+1
+.endr
+
+#define BUILD_SMP_INTERRUPT(name, nr)	\
+ENTRY(name)				\
+	pushl $nr-256;			\
+	SAVE_ALL			\
+	call SYMBOL_NAME(smp_/**/name);	\
+	jmp ret_from_intr;
+
+#define BUILD_SMP_TIMER_INTERRUPT(name, nr) \
+ENTRY(name)				\
+	pushl $nr-256;			\
+	SAVE_ALL			\
+	movl %esp,%eax;			\
+	pushl %eax;			\
+	call SYMBOL_NAME(smp_/**/name);	\
+	addl $4,%esp;			\
+	jmp ret_from_intr;
+
+/*
+ * The following vectors are part of the Linux architecture, there
+ * is no hardware IRQ pin equivalent for them, they are triggered
+ * through the ICC by us (IPIs)
+ */
+#ifdef CONFIG_SMP
+BUILD_SMP_INTERRUPT(reschedule_interrupt,RESCHEDULE_VECTOR)
+BUILD_SMP_INTERRUPT(invalidate_interrupt,INVALIDATE_TLB_VECTOR)
+BUILD_SMP_INTERRUPT(call_function_interrupt,CALL_FUNCTION_VECTOR)
+#endif
+
+/*
+ * every pentium local APIC has two 'local interrupts', with a
+ * soft-definable vector attached to both interrupts, one of
+ * which is a timer interrupt, the other one is error counter
+ * overflow. Linux uses the local APIC timer interrupt to get
+ * a much simpler SMP time architecture:
+ */
+#ifdef CONFIG_X86_LOCAL_APIC
+BUILD_SMP_TIMER_INTERRUPT(apic_timer_interrupt,LOCAL_TIMER_VECTOR)
+BUILD_SMP_INTERRUPT(error_interrupt,ERROR_APIC_VECTOR)
+BUILD_SMP_INTERRUPT(spurious_interrupt,SPURIOUS_APIC_VECTOR)
+#endif
+
 	ALIGN
 reschedule:
 	call SYMBOL_NAME(schedule)    # test
 	jmp ret_from_sys_call
 
+/*
+ * Trap and fault entry points
+ */
 ENTRY(divide_error)
 	pushl $0		# no error code
 	pushl $ SYMBOL_NAME(do_divide_error)