x86/entry/64: Shrink paranoid_exit_restore and make labels local

paranoid_exit_restore was a copy of restore_regs_and_return_to_kernel.
Merge them and make the paranoid_exit internal labels local.

Keeping .Lparanoid_exit makes the code a bit shorter because it
allows a 2-byte jnz instead of a 5-byte jnz.

Saves 96 bytes of text.

( This is still a bit suboptimal in a non-CONFIG_TRACE_IRQFLAGS
  kernel, but fixing that would make the code rather messy. )

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/510d66a1895cda9473c84b1086f0bb974f22de6a.1509609304.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 925d562..1553964 100644 (file)
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1123,17 +1123,14 @@ ENTRY(paranoid_exit)
        DISABLE_INTERRUPTS(CLBR_ANY)
        TRACE_IRQS_OFF_DEBUG
        testl   %ebx, %ebx                      /* swapgs needed? */
-       jnz     paranoid_exit_no_swapgs
+       jnz     .Lparanoid_exit_no_swapgs
        TRACE_IRQS_IRETQ
        SWAPGS_UNSAFE_STACK
-       jmp     paranoid_exit_restore
-paranoid_exit_no_swapgs:
+       jmp     .Lparanoid_exit_restore
+.Lparanoid_exit_no_swapgs:
        TRACE_IRQS_IRETQ_DEBUG
-paranoid_exit_restore:
-       RESTORE_EXTRA_REGS
-       RESTORE_C_REGS
-       REMOVE_PT_GPREGS_FROM_STACK 8
-       INTERRUPT_RETURN
+.Lparanoid_exit_restore:
+       jmp restore_regs_and_return_to_kernel
 END(paranoid_exit)
 
 /*