[PATCH 2/5] x86: ret_from_fork - get rid of jump back

[gorcunov]

From: Cyrill Gorcunov <gorcunov@xxxxxxxxx>

Impact: cleanup, microoptimization

Use straightforward jumping if possible, cpu like it.

Signed-off-by: Cyrill Gorcunov <gorcunov@xxxxxxxxx>
---
 arch/x86/kernel/entry_64.S |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 098ba0b..7b52b0f 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -379,7 +379,10 @@ ENTRY(ret_from_fork)
 	GET_THREAD_INFO(%rcx)
 	testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),TI_flags(%rcx)
 	CFI_REMEMBER_STATE
-	jnz rff_trace
+	jz rff_action
+	movq %rsp,%rdi
+	call syscall_trace_leave
+	GET_THREAD_INFO(%rcx)
 rff_action:
 	RESTORE_REST
 	testl $3,CS-ARGOFFSET(%rsp)	# from kernel_thread?
@@ -389,11 +392,6 @@ rff_action:
 	RESTORE_TOP_OF_STACK %rdi, -ARGOFFSET
 	jmp ret_from_sys_call
 	CFI_RESTORE_STATE
-rff_trace:
-	movq %rsp,%rdi
-	call syscall_trace_leave
-	GET_THREAD_INFO(%rcx)
-	jmp rff_action
 	CFI_ENDPROC
 END(ret_from_fork)
 
-- 
1.6.0.4.603.gbc9c0

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