[PATCH V5 2/2] arm64: copy_to-from-in_user optimization using copy template
Feng Kan
fkan at apm.com
Wed Sep 23 11:55:39 PDT 2015
This patch optimize copy_to-from-in_user for arm 64bit architecture. The
copy template is used as template file for all the copy*.S files. Minor
change was made to it to accommodate the copy to/from/in user files.
Signed-off-by: Feng Kan <fkan at apm.com>
Signed-off-by: Balamurugan Shanmugam <bshanmugam at apm.com>
---
arch/arm64/lib/copy_from_user.S | 78 +++++++++++++++++++++++------------------
arch/arm64/lib/copy_in_user.S | 67 ++++++++++++++++++++---------------
arch/arm64/lib/copy_to_user.S | 67 ++++++++++++++++++++---------------
3 files changed, 120 insertions(+), 92 deletions(-)
diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S
index 1be9ef2..4699cd7 100644
--- a/arch/arm64/lib/copy_from_user.S
+++ b/arch/arm64/lib/copy_from_user.S
@@ -18,6 +18,7 @@
#include <asm/alternative.h>
#include <asm/assembler.h>
+#include <asm/cache.h>
#include <asm/cpufeature.h>
#include <asm/sysreg.h>
@@ -31,49 +32,58 @@
* Returns:
* x0 - bytes not copied
*/
+
+ .macro ldrb1 ptr, regB, val
+ USER(9998f, ldrb \ptr, [\regB], \val)
+ .endm
+
+ .macro strb1 ptr, regB, val
+ strb \ptr, [\regB], \val
+ .endm
+
+ .macro ldrh1 ptr, regB, val
+ USER(9998f, ldrh \ptr, [\regB], \val)
+ .endm
+
+ .macro strh1 ptr, regB, val
+ strh \ptr, [\regB], \val
+ .endm
+
+ .macro ldr1 ptr, regB, val
+ USER(9998f, ldr \ptr, [\regB], \val)
+ .endm
+
+ .macro str1 ptr, regB, val
+ str \ptr, [\regB], \val
+ .endm
+
+ .macro ldp1 ptr, regB, regC, val
+ USER(9998f, ldp \ptr, \regB, [\regC], \val)
+ .endm
+
+ .macro stp1 ptr, regB, regC, val
+ stp \ptr, \regB, [\regC], \val
+ .endm
+
+end .req x5
ENTRY(__copy_from_user)
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
- add x5, x1, x2 // upper user buffer boundary
- subs x2, x2, #16
- b.mi 1f
-0:
-USER(9f, ldp x3, x4, [x1], #16)
- subs x2, x2, #16
- stp x3, x4, [x0], #16
- b.pl 0b
-1: adds x2, x2, #8
- b.mi 2f
-USER(9f, ldr x3, [x1], #8 )
- sub x2, x2, #8
- str x3, [x0], #8
-2: adds x2, x2, #4
- b.mi 3f
-USER(9f, ldr w3, [x1], #4 )
- sub x2, x2, #4
- str w3, [x0], #4
-3: adds x2, x2, #2
- b.mi 4f
-USER(9f, ldrh w3, [x1], #2 )
- sub x2, x2, #2
- strh w3, [x0], #2
-4: adds x2, x2, #1
- b.mi 5f
-USER(9f, ldrb w3, [x1] )
- strb w3, [x0]
-5: mov x0, #0
+ add end, x0, x2
+#include "copy_template.S"
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
+ mov x0, #0 // Nothing to copy
ret
ENDPROC(__copy_from_user)
.section .fixup,"ax"
.align 2
-9: sub x2, x5, x1
- mov x3, x2
-10: strb wzr, [x0], #1 // zero remaining buffer space
- subs x3, x3, #1
- b.ne 10b
- mov x0, x2 // bytes not copied
+9998:
+ sub x0, end, dst
+9999:
+ strb wzr, [dst], #1 // zero remaining buffer space
+ cmp dst, end
+ b.lo 9999b
ret
.previous
diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S
index 1b94661e..81c8fc9 100644
--- a/arch/arm64/lib/copy_in_user.S
+++ b/arch/arm64/lib/copy_in_user.S
@@ -20,6 +20,7 @@
#include <asm/alternative.h>
#include <asm/assembler.h>
+#include <asm/cache.h>
#include <asm/cpufeature.h>
#include <asm/sysreg.h>
@@ -33,44 +34,52 @@
* Returns:
* x0 - bytes not copied
*/
+ .macro ldrb1 ptr, regB, val
+ USER(9998f, ldrb \ptr, [\regB], \val)
+ .endm
+
+ .macro strb1 ptr, regB, val
+ USER(9998f, strb \ptr, [\regB], \val)
+ .endm
+
+ .macro ldrh1 ptr, regB, val
+ USER(9998f, ldrh \ptr, [\regB], \val)
+ .endm
+
+ .macro strh1 ptr, regB, val
+ USER(9998f, strh \ptr, [\regB], \val)
+ .endm
+
+ .macro ldr1 ptr, regB, val
+ USER(9998f, ldr \ptr, [\regB], \val)
+ .endm
+
+ .macro str1 ptr, regB, val
+ USER(9998f, str \ptr, [\regB], \val)
+ .endm
+
+ .macro ldp1 ptr, regB, regC, val
+ USER(9998f, ldp \ptr, \regB, [\regC], \val)
+ .endm
+
+ .macro stp1 ptr, regB, regC, val
+ USER(9998f, stp \ptr, \regB, [\regC], \val)
+ .endm
+
+end .req x5
ENTRY(__copy_in_user)
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
- add x5, x0, x2 // upper user buffer boundary
- subs x2, x2, #16
- b.mi 1f
-0:
-USER(9f, ldp x3, x4, [x1], #16)
- subs x2, x2, #16
-USER(9f, stp x3, x4, [x0], #16)
- b.pl 0b
-1: adds x2, x2, #8
- b.mi 2f
-USER(9f, ldr x3, [x1], #8 )
- sub x2, x2, #8
-USER(9f, str x3, [x0], #8 )
-2: adds x2, x2, #4
- b.mi 3f
-USER(9f, ldr w3, [x1], #4 )
- sub x2, x2, #4
-USER(9f, str w3, [x0], #4 )
-3: adds x2, x2, #2
- b.mi 4f
-USER(9f, ldrh w3, [x1], #2 )
- sub x2, x2, #2
-USER(9f, strh w3, [x0], #2 )
-4: adds x2, x2, #1
- b.mi 5f
-USER(9f, ldrb w3, [x1] )
-USER(9f, strb w3, [x0] )
-5: mov x0, #0
+ add end, x0, x2
+#include "copy_template.S"
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
+ mov x0, #0
ret
ENDPROC(__copy_in_user)
.section .fixup,"ax"
.align 2
-9: sub x0, x5, x0 // bytes not copied
+9998: sub x0, end, dst // bytes not copied
ret
.previous
diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S
index a257b47..7512bbb 100644
--- a/arch/arm64/lib/copy_to_user.S
+++ b/arch/arm64/lib/copy_to_user.S
@@ -18,6 +18,7 @@
#include <asm/alternative.h>
#include <asm/assembler.h>
+#include <asm/cache.h>
#include <asm/cpufeature.h>
#include <asm/sysreg.h>
@@ -31,44 +32,52 @@
* Returns:
* x0 - bytes not copied
*/
+ .macro ldrb1 ptr, regB, val
+ ldrb \ptr, [\regB], \val
+ .endm
+
+ .macro strb1 ptr, regB, val
+ USER(9998f, strb \ptr, [\regB], \val)
+ .endm
+
+ .macro ldrh1 ptr, regB, val
+ ldrh \ptr, [\regB], \val
+ .endm
+
+ .macro strh1 ptr, regB, val
+ USER(9998f, strh \ptr, [\regB], \val)
+ .endm
+
+ .macro ldr1 ptr, regB, val
+ ldr \ptr, [\regB], \val
+ .endm
+
+ .macro str1 ptr, regB, val
+ USER(9998f, str \ptr, [\regB], \val)
+ .endm
+
+ .macro ldp1 ptr, regB, regC, val
+ ldp \ptr, \regB, [\regC], \val
+ .endm
+
+ .macro stp1 ptr, regB, regC, val
+ USER(9998f, stp \ptr, \regB, [\regC], \val)
+ .endm
+
+end .req x5
ENTRY(__copy_to_user)
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
- add x5, x0, x2 // upper user buffer boundary
- subs x2, x2, #16
- b.mi 1f
-0:
- ldp x3, x4, [x1], #16
- subs x2, x2, #16
-USER(9f, stp x3, x4, [x0], #16)
- b.pl 0b
-1: adds x2, x2, #8
- b.mi 2f
- ldr x3, [x1], #8
- sub x2, x2, #8
-USER(9f, str x3, [x0], #8 )
-2: adds x2, x2, #4
- b.mi 3f
- ldr w3, [x1], #4
- sub x2, x2, #4
-USER(9f, str w3, [x0], #4 )
-3: adds x2, x2, #2
- b.mi 4f
- ldrh w3, [x1], #2
- sub x2, x2, #2
-USER(9f, strh w3, [x0], #2 )
-4: adds x2, x2, #1
- b.mi 5f
- ldrb w3, [x1]
-USER(9f, strb w3, [x0] )
-5: mov x0, #0
+ add end, x0, x2
+#include "copy_template.S"
ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_HAS_PAN, \
CONFIG_ARM64_PAN)
+ mov x0, #0
ret
ENDPROC(__copy_to_user)
.section .fixup,"ax"
.align 2
-9: sub x0, x5, x0 // bytes not copied
+9998: sub x0, end, dst // bytes not copied
ret
.previous
--
1.9.1
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