From: David Howells <dhowells@redhat.com>
Date: Tue, 1 May 2012 20:31:42 +0000 (+0100)
Subject: FRV: Optimise the system call exit path in entry.S [ver #2]
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=a2eddc7c491c916ff9ba39b3563cd779e7b58320;p=openwrt%2Fstaging%2Fblogic.git

FRV: Optimise the system call exit path in entry.S [ver #2]

Optimise the system call exit path in entry.S by packing some instructions.

Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/arch/frv/kernel/entry.S b/arch/frv/kernel/entry.S
index 03da263e112a..7d5e000fd32e 100644
--- a/arch/frv/kernel/entry.S
+++ b/arch/frv/kernel/entry.S
@@ -905,18 +905,19 @@ __syscall_call:
 __syscall_exit:
 	LEDS		0x6300
 
-	sti		gr8,@(gr28,#REG_GR(8))	; save return value
+	# keep current PSR in GR23
+	movsg		psr,gr23
 
-	# rebuild saved psr - execve will change it for init/main.c
 	ldi		@(gr28,#REG_PSR),gr22
+
+	sti.p		gr8,@(gr28,#REG_GR(8))	; save return value
+
+	# rebuild saved psr - execve will change it for init/main.c
 	srli		gr22,#1,gr5
 	andi.p		gr22,#~PSR_PS,gr22
 	andi		gr5,#PSR_PS,gr5
 	or		gr5,gr22,gr22
-	ori		gr22,#PSR_S,gr22
-
-	# keep current PSR in GR23
-	movsg		psr,gr23
+	ori.p		gr22,#PSR_S,gr22
 
 	# make sure we don't miss an interrupt setting need_resched or sigpending between
 	# sampling and the RETT