mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
* [PATCH] x86-64: slightly shorten copy_page()
@ 2012-01-05 16:12 Jan Beulich
  2012-01-08  4:39 ` [tip:x86/asm] x86-64: Slightly " tip-bot for Jan Beulich
  0 siblings, 1 reply; 2+ messages in thread
From: Jan Beulich @ 2012-01-05 16:12 UTC (permalink / raw)
  To: mingo, tglx, hpa; +Cc: linux-kernel

%r13 got saved and restored without ever getting touched, so there's
no need to do so.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

---
 arch/x86/lib/copy_page_64.S |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

--- 3.2/arch/x86/lib/copy_page_64.S
+++ 3.2-x86_64-copy_page/arch/x86/lib/copy_page_64.S
@@ -20,14 +20,12 @@ ENDPROC(copy_page_c)
 
 ENTRY(copy_page)
 	CFI_STARTPROC
-	subq	$3*8,%rsp
-	CFI_ADJUST_CFA_OFFSET 3*8
+	subq	$2*8,%rsp
+	CFI_ADJUST_CFA_OFFSET 2*8
 	movq	%rbx,(%rsp)
 	CFI_REL_OFFSET rbx, 0
 	movq	%r12,1*8(%rsp)
 	CFI_REL_OFFSET r12, 1*8
-	movq	%r13,2*8(%rsp)
-	CFI_REL_OFFSET r13, 2*8
 
 	movl	$(4096/64)-5,%ecx
 	.p2align 4
@@ -91,10 +89,8 @@ ENTRY(copy_page)
 	CFI_RESTORE rbx
 	movq	1*8(%rsp),%r12
 	CFI_RESTORE r12
-	movq	2*8(%rsp),%r13
-	CFI_RESTORE r13
-	addq	$3*8,%rsp
-	CFI_ADJUST_CFA_OFFSET -3*8
+	addq	$2*8,%rsp
+	CFI_ADJUST_CFA_OFFSET -2*8
 	ret
 .Lcopy_page_end:
 	CFI_ENDPROC




^ permalink raw reply	[flat|nested] 2+ messages in thread

* [tip:x86/asm] x86-64: Slightly shorten copy_page()
  2012-01-05 16:12 [PATCH] x86-64: slightly shorten copy_page() Jan Beulich
@ 2012-01-08  4:39 ` tip-bot for Jan Beulich
  0 siblings, 0 replies; 2+ messages in thread
From: tip-bot for Jan Beulich @ 2012-01-08  4:39 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, torvalds, jbeulich, akpm, JBeulich,
	tglx, mingo

Commit-ID:  426932909093e4e7729777a0e2beed4b54911361
Gitweb:     http://git.kernel.org/tip/426932909093e4e7729777a0e2beed4b54911361
Author:     Jan Beulich <JBeulich@suse.com>
AuthorDate: Thu, 5 Jan 2012 16:12:25 +0000
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 6 Jan 2012 12:25:37 +0100

x86-64: Slightly shorten copy_page()

%r13 got saved and restored without ever getting touched, so
there's no need to do so.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/4F05D9F9020000780006AA0D@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/lib/copy_page_64.S |   12 ++++--------
 1 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/arch/x86/lib/copy_page_64.S b/arch/x86/lib/copy_page_64.S
index 01c805b..6b34d04 100644
--- a/arch/x86/lib/copy_page_64.S
+++ b/arch/x86/lib/copy_page_64.S
@@ -20,14 +20,12 @@ ENDPROC(copy_page_c)
 
 ENTRY(copy_page)
 	CFI_STARTPROC
-	subq	$3*8,%rsp
-	CFI_ADJUST_CFA_OFFSET 3*8
+	subq	$2*8,%rsp
+	CFI_ADJUST_CFA_OFFSET 2*8
 	movq	%rbx,(%rsp)
 	CFI_REL_OFFSET rbx, 0
 	movq	%r12,1*8(%rsp)
 	CFI_REL_OFFSET r12, 1*8
-	movq	%r13,2*8(%rsp)
-	CFI_REL_OFFSET r13, 2*8
 
 	movl	$(4096/64)-5,%ecx
 	.p2align 4
@@ -91,10 +89,8 @@ ENTRY(copy_page)
 	CFI_RESTORE rbx
 	movq	1*8(%rsp),%r12
 	CFI_RESTORE r12
-	movq	2*8(%rsp),%r13
-	CFI_RESTORE r13
-	addq	$3*8,%rsp
-	CFI_ADJUST_CFA_OFFSET -3*8
+	addq	$2*8,%rsp
+	CFI_ADJUST_CFA_OFFSET -2*8
 	ret
 .Lcopy_page_end:
 	CFI_ENDPROC

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2012-01-08  4:41 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-01-05 16:12 [PATCH] x86-64: slightly shorten copy_page() Jan Beulich
2012-01-08  4:39 ` [tip:x86/asm] x86-64: Slightly " tip-bot for Jan Beulich

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome