Re: [PATCH v2 1/3] x86/hash: fix build failure with older binutils
On 02/27/2014 09:47 AM, Jan Beulich wrote: Just like for other ISA extension instruction uses we should check whether the assembler actually supports them. The fallback here simply is to encode an instruction with fixed operands (%eax and %ecx). Signed-off-by: Jan Beulich Cc: Francesco Fusco Cc: Daniel Borkmann Cc: Thomas Graf Cc: David S. Miller Acked-by: Daniel Borkmann -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH v2 1/3] x86/hash: fix build failure with older binutils
Just like for other ISA extension instruction uses we should check
whether the assembler actually supports them. The fallback here simply
is to encode an instruction with fixed operands (%eax and %ecx).
Signed-off-by: Jan Beulich
Cc: Francesco Fusco
Cc: Daniel Borkmann
Cc: Thomas Graf
Cc: David S. Miller
---
arch/x86/Makefile |1 +
arch/x86/lib/hash.c |4
2 files changed, 5 insertions(+)
--- 3.14-rc4-x86-hash-crc32.orig/arch/x86/Makefile
+++ 3.14-rc4-x86-hash-crc32/arch/x86/Makefile
@@ -152,6 +152,7 @@ cfi-sections := $(call as-instr,.cfi_sec
# does binutils support specific instructions?
asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1)
+asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1)
avx_instr := $(call as-instr,vxorps
%ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1)
avx2_instr :=$(call as-instr,vpbroadcastb
%xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1)
--- 3.14-rc4-x86-hash-crc32.orig/arch/x86/lib/hash.c
+++ 3.14-rc4-x86-hash-crc32/arch/x86/lib/hash.c
@@ -39,7 +39,11 @@
static inline u32 crc32_u32(u32 crc, u32 val)
{
+#ifdef CONFIG_AS_CRC32
asm ("crc32l %1,%0\n" : "+r" (crc) : "rm" (val));
+#else
+ asm (".byte 0xf2, 0x0f, 0x38, 0xf1, 0xc1" : "+a" (crc) : "c" (val));
+#endif
return crc;
}
--
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[PATCH v2 1/3] x86/hash: fix build failure with older binutils
Just like for other ISA extension instruction uses we should check
whether the assembler actually supports them. The fallback here simply
is to encode an instruction with fixed operands (%eax and %ecx).
Signed-off-by: Jan Beulich jbeul...@suse.com
Cc: Francesco Fusco ffu...@redhat.com
Cc: Daniel Borkmann dbork...@redhat.com
Cc: Thomas Graf tg...@redhat.com
Cc: David S. Miller da...@davemloft.net
---
arch/x86/Makefile |1 +
arch/x86/lib/hash.c |4
2 files changed, 5 insertions(+)
--- 3.14-rc4-x86-hash-crc32.orig/arch/x86/Makefile
+++ 3.14-rc4-x86-hash-crc32/arch/x86/Makefile
@@ -152,6 +152,7 @@ cfi-sections := $(call as-instr,.cfi_sec
# does binutils support specific instructions?
asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1)
+asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1)
avx_instr := $(call as-instr,vxorps
%ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1)
avx2_instr :=$(call as-instr,vpbroadcastb
%xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1)
--- 3.14-rc4-x86-hash-crc32.orig/arch/x86/lib/hash.c
+++ 3.14-rc4-x86-hash-crc32/arch/x86/lib/hash.c
@@ -39,7 +39,11 @@
static inline u32 crc32_u32(u32 crc, u32 val)
{
+#ifdef CONFIG_AS_CRC32
asm (crc32l %1,%0\n : +r (crc) : rm (val));
+#else
+ asm (.byte 0xf2, 0x0f, 0x38, 0xf1, 0xc1 : +a (crc) : c (val));
+#endif
return crc;
}
--
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Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH v2 1/3] x86/hash: fix build failure with older binutils
On 02/27/2014 09:47 AM, Jan Beulich wrote: Just like for other ISA extension instruction uses we should check whether the assembler actually supports them. The fallback here simply is to encode an instruction with fixed operands (%eax and %ecx). Signed-off-by: Jan Beulich jbeul...@suse.com Cc: Francesco Fusco ffu...@redhat.com Cc: Daniel Borkmann dbork...@redhat.com Cc: Thomas Graf tg...@redhat.com Cc: David S. Miller da...@davemloft.net Acked-by: Daniel Borkmann dbork...@redhat.com -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
