Merge branch 'x86/cleanups' into x86/irq

[safe/jmp/linux-2.6] / arch / x86 / kernel / entry_64.S

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 5492778..dbf06a0 100644 (file)
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -627,6 +627,46 @@ END(stub_rt_sigreturn)
    vector already pushed) */
 #define XCPT_FRAME _frame ORIG_RAX
 
+/*
+ * Build the entry stubs and pointer table with some assembler magic.
+ * We pack 7 stubs into a single 32-byte chunk, which will fit in a
+ * single cache line on all modern x86 implementations.
+ */
+       .section .init.rodata,"a"
+ENTRY(interrupt)
+       .text
+       .p2align 5
+       .p2align CONFIG_X86_L1_CACHE_SHIFT
+ENTRY(irq_entries_start)
+       INTR_FRAME
+vector=FIRST_EXTERNAL_VECTOR
+.rept (NR_VECTORS-FIRST_EXTERNAL_VECTOR+6)/7
+       .balign 32
+  .rept        7
+    .if vector < NR_VECTORS
+      .if vector <> FIRST_EXTERNAL_VECTOR
+       CFI_ADJUST_CFA_OFFSET -8
+      .endif
+1:     pushq $(~vector+0x80)   /* Note: always in signed byte range */
+       CFI_ADJUST_CFA_OFFSET 8
+      .if ((vector-FIRST_EXTERNAL_VECTOR)%7) <> 6
+       jmp 2f
+      .endif
+      .previous
+       .quad 1b
+      .text
+vector=vector+1
+    .endif
+  .endr
+2:     jmp common_interrupt
+.endr
+       CFI_ENDPROC
+END(irq_entries_start)
+
+.previous
+END(interrupt)
+.previous
+
 /* 
  * Interrupt entry/exit.
  *
@@ -635,11 +675,11 @@ END(stub_rt_sigreturn)
  * Entry runs with interrupts off.     
  */ 
 
-/* 0(%rsp): interrupt number */ 
+/* 0(%rsp): ~(interrupt number) */
        .macro interrupt func
        cld
        SAVE_ARGS
-       leaq -ARGOFFSET(%rsp),%rdi      # arg1 for handler
+       leaq -ARGOFFSET(%rsp),%rdi      /* arg1 for handler */
        pushq %rbp
        /*
         * Save rbp twice: One is for marking the stack frame, as usual, and the
@@ -670,8 +710,14 @@ END(stub_rt_sigreturn)
        call \func
        .endm
 
-ENTRY(common_interrupt)
+       /*
+        * The interrupt stubs push (~vector+0x80) onto the stack and
+        * then jump to common_interrupt.
+        */
+       .p2align CONFIG_X86_L1_CACHE_SHIFT
+common_interrupt:
        XCPT_FRAME
+       addq $-0x80,(%rsp)              /* Adjust vector to [-256,-1] range */
        interrupt do_IRQ
        /* 0(%rsp): oldrsp-ARGOFFSET */
 ret_from_intr: