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[RFC 05/17] x86/asm/64: Shrink paranoid_exit_restore and make labels local

Started byAndy Lutomirski <luto@kernel.org>
First post2017-09-06 23:40 +0200
Last post2017-09-06 23:40 +0200
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  [RFC 05/17] x86/asm/64: Shrink paranoid_exit_restore and make labels local Andy Lutomirski <luto@kernel.org> - 2017-09-06 23:40 +0200

#1727756 — [RFC 05/17] x86/asm/64: Shrink paranoid_exit_restore and make labels local

FromAndy Lutomirski <luto@kernel.org>
Date2017-09-06 23:40 +0200
Subject[RFC 05/17] x86/asm/64: Shrink paranoid_exit_restore and make labels local
Message-ID<umQdc-7qi-11@gated-at.bofh.it>
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>
---
 arch/x86/entry/entry_64.S | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 7f1a83b17b4a..741b7dc1758b 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1057,17 +1057,14 @@ 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)
 
 /*
-- 
2.13.5

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