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author | Feng Kan <fkan@apm.com> | 2015-09-23 18:55:39 (GMT) |
---|---|---|
committer | Catalin Marinas <catalin.marinas@arm.com> | 2015-10-07 10:34:44 (GMT) |
commit | 404268828c74ba06b1f21584b26edafb381c9d7d (patch) | |
tree | 3bd7d62e4a98e500158921d80021fcf0f7c35f11 /arch/arm64/lib/copy_to_user.S | |
parent | e5c88e3f2fb35dca5f3e46d65095bf5d008595b7 (diff) | |
download | linux-404268828c74ba06b1f21584b26edafb381c9d7d.tar.xz |
arm64: copy_to-from-in_user optimization using copy template
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@apm.com>
Signed-off-by: Balamurugan Shanmugam <bshanmugam@apm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/lib/copy_to_user.S')
-rw-r--r-- | arch/arm64/lib/copy_to_user.S | 67 |
1 files changed, 38 insertions, 29 deletions
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 |