| Message ID | 20180522065701.9DE696CCB4@po14934vm.idsi0.si.c-s.fr |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | [v3] powerpc: Implement csum_ipv6_magic in assembly | expand |
On Tue, May 22, 2018 at 08:57:01AM +0200, Christophe Leroy wrote: > The generic csum_ipv6_magic() generates a pretty bad result <snip> Please try with a more recent compiler, what you used is pretty ancient. It's not like recent compilers do great on this either, but it's not *that* bad anymore ;-) > --- a/arch/powerpc/lib/checksum_32.S > +++ b/arch/powerpc/lib/checksum_32.S > @@ -293,3 +293,36 @@ dst_error: > EX_TABLE(51b, dst_error); > > EXPORT_SYMBOL(csum_partial_copy_generic) > + > +/* > + * static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, > + * const struct in6_addr *daddr, > + * __u32 len, __u8 proto, __wsum sum) > + */ > + > +_GLOBAL(csum_ipv6_magic) > + lwz r8, 0(r3) > + lwz r9, 4(r3) > + lwz r10, 8(r3) > + lwz r11, 12(r3) > + addc r0, r5, r6 > + adde r0, r0, r7 > + adde r0, r0, r8 > + adde r0, r0, r9 > + adde r0, r0, r10 > + adde r0, r0, r11 > + lwz r8, 0(r4) > + lwz r9, 4(r4) > + lwz r10, 8(r4) > + lwz r11, 12(r4) > + adde r0, r0, r8 > + adde r0, r0, r9 > + adde r0, r0, r10 > + adde r0, r0, r11 > + addze r0, r0 > + rotlwi r3, r0, 16 > + add r3, r0, r3 > + not r3, r3 > + rlwinm r3, r3, 16, 16, 31 > + blr > +EXPORT_SYMBOL(csum_ipv6_magic) Clustering the loads and carry insns together is pretty much the worst you can do on most 32-bit CPUs. Segher
Le 23/05/2018 à 20:34, Segher Boessenkool a écrit : > On Tue, May 22, 2018 at 08:57:01AM +0200, Christophe Leroy wrote: >> The generic csum_ipv6_magic() generates a pretty bad result > > <snip> > > Please try with a more recent compiler, what you used is pretty ancient. > It's not like recent compilers do great on this either, but it's not > *that* bad anymore ;-) > >> --- a/arch/powerpc/lib/checksum_32.S >> +++ b/arch/powerpc/lib/checksum_32.S >> @@ -293,3 +293,36 @@ dst_error: >> EX_TABLE(51b, dst_error); >> >> EXPORT_SYMBOL(csum_partial_copy_generic) >> + >> +/* >> + * static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, >> + * const struct in6_addr *daddr, >> + * __u32 len, __u8 proto, __wsum sum) >> + */ >> + >> +_GLOBAL(csum_ipv6_magic) >> + lwz r8, 0(r3) >> + lwz r9, 4(r3) >> + lwz r10, 8(r3) >> + lwz r11, 12(r3) >> + addc r0, r5, r6 >> + adde r0, r0, r7 >> + adde r0, r0, r8 >> + adde r0, r0, r9 >> + adde r0, r0, r10 >> + adde r0, r0, r11 >> + lwz r8, 0(r4) >> + lwz r9, 4(r4) >> + lwz r10, 8(r4) >> + lwz r11, 12(r4) >> + adde r0, r0, r8 >> + adde r0, r0, r9 >> + adde r0, r0, r10 >> + adde r0, r0, r11 >> + addze r0, r0 >> + rotlwi r3, r0, 16 >> + add r3, r0, r3 >> + not r3, r3 >> + rlwinm r3, r3, 16, 16, 31 >> + blr >> +EXPORT_SYMBOL(csum_ipv6_magic) > > Clustering the loads and carry insns together is pretty much the worst you > can do on most 32-bit CPUs. Oh, really ? __csum_partial is written that way too. Right, now I tried interleaving the lwz and adde. I get no improvment at all on a 885, but I get a 15% improvment on a 8321. Christophe > > > Segher >
On 05/24/2018 06:20 AM, Christophe LEROY wrote: > > > Le 23/05/2018 à 20:34, Segher Boessenkool a écrit : >> On Tue, May 22, 2018 at 08:57:01AM +0200, Christophe Leroy wrote: >>> The generic csum_ipv6_magic() generates a pretty bad result >> >> <snip> >> >> Please try with a more recent compiler, what you used is pretty ancient. >> It's not like recent compilers do great on this either, but it's not >> *that* bad anymore ;-) Here is what I get with GCC 8.1 It doesn't look much better, does it ? net/ipv6/ip6_checksum.o: file format elf32-powerpc Disassembly of section .text: 00000000 <csum_ipv6_magic>: 0: 94 21 ff f0 stwu r1,-16(r1) 4: 80 04 00 00 lwz r0,0(r4) 8: 81 64 00 04 lwz r11,4(r4) c: 81 04 00 08 lwz r8,8(r4) 10: 93 e1 00 0c stw r31,12(r1) 14: 81 43 00 00 lwz r10,0(r3) 18: 83 e3 00 04 lwz r31,4(r3) 1c: 81 23 00 08 lwz r9,8(r3) 20: 81 83 00 0c lwz r12,12(r3) 24: 7c ea 3a 14 add r7,r10,r7 28: 7d 4a 38 10 subfc r10,r10,r7 2c: 7c ff 3a 14 add r7,r31,r7 30: 81 44 00 0c lwz r10,12(r4) 34: 7c 63 19 10 subfe r3,r3,r3 38: 7c 63 38 50 subf r3,r3,r7 3c: 7f ff 18 10 subfc r31,r31,r3 40: 7c e9 1a 14 add r7,r9,r3 44: 83 e1 00 0c lwz r31,12(r1) 48: 7c 63 19 10 subfe r3,r3,r3 4c: 38 21 00 10 addi r1,r1,16 50: 7c 63 38 50 subf r3,r3,r7 54: 7d 29 18 10 subfc r9,r9,r3 58: 7d 2c 1a 14 add r9,r12,r3 5c: 7c 63 19 10 subfe r3,r3,r3 60: 7c 63 48 50 subf r3,r3,r9 64: 7d 8c 18 10 subfc r12,r12,r3 68: 7d 20 1a 14 add r9,r0,r3 6c: 7c 63 19 10 subfe r3,r3,r3 70: 7c 63 48 50 subf r3,r3,r9 74: 7c 00 18 10 subfc r0,r0,r3 78: 7d 2b 1a 14 add r9,r11,r3 7c: 7c 63 19 10 subfe r3,r3,r3 80: 7c 63 48 50 subf r3,r3,r9 84: 7d 6b 18 10 subfc r11,r11,r3 88: 7d 28 1a 14 add r9,r8,r3 8c: 7c 63 19 10 subfe r3,r3,r3 90: 7c 63 48 50 subf r3,r3,r9 94: 7d 08 18 10 subfc r8,r8,r3 98: 7d 2a 1a 14 add r9,r10,r3 9c: 7c 63 19 10 subfe r3,r3,r3 a0: 7c 63 48 50 subf r3,r3,r9 a4: 7d 4a 18 10 subfc r10,r10,r3 a8: 7d 23 2a 14 add r9,r3,r5 ac: 7c 63 19 10 subfe r3,r3,r3 b0: 7c 63 48 50 subf r3,r3,r9 b4: 7c a5 18 10 subfc r5,r5,r3 b8: 7c 63 32 14 add r3,r3,r6 bc: 7d 29 49 10 subfe r9,r9,r9 c0: 7d 29 18 50 subf r9,r9,r3 c4: 7c c6 48 10 subfc r6,r6,r9 c8: 7c 63 19 10 subfe r3,r3,r3 cc: 7c 63 48 50 subf r3,r3,r9 d0: 54 69 80 3e rotlwi r9,r3,16 d4: 7c 63 4a 14 add r3,r3,r9 d8: 7c 63 18 f8 not r3,r3 dc: 54 63 84 3e rlwinm r3,r3,16,16,31 e0: 4e 80 00 20 blr net/ipv6/ip6_checksum.o: file format elf64-powerpc Disassembly of section .text: 0000000000000000 <.csum_ipv6_magic>: 0: fb e1 ff f8 std r31,-8(r1) 4: 81 43 00 00 lwz r10,0(r3) 8: 81 83 00 04 lwz r12,4(r3) c: 81 23 00 08 lwz r9,8(r3) 10: 80 03 00 0c lwz r0,12(r3) 14: 7c e7 52 14 add r7,r7,r10 18: 80 64 00 08 lwz r3,8(r4) 1c: 81 04 00 00 lwz r8,0(r4) 20: 78 ff 00 20 clrldi r31,r7,32 24: 7c ec 3a 14 add r7,r12,r7 28: 81 64 00 04 lwz r11,4(r4) 2c: 7f ea f8 50 subf r31,r10,r31 30: 81 44 00 0c lwz r10,12(r4) 34: 7b ff 0f e0 rldicl r31,r31,1,63 38: 7c ff 3a 14 add r7,r31,r7 3c: eb e1 ff f8 ld r31,-8(r1) 40: 78 e4 00 20 clrldi r4,r7,32 44: 7c e9 3a 14 add r7,r9,r7 48: 7d 8c 20 50 subf r12,r12,r4 4c: 79 8c 0f e0 rldicl r12,r12,1,63 50: 7d 8c 3a 14 add r12,r12,r7 54: 79 87 00 20 clrldi r7,r12,32 58: 7d 80 62 14 add r12,r0,r12 5c: 7d 29 38 50 subf r9,r9,r7 60: 79 29 0f e0 rldicl r9,r9,1,63 64: 7d 29 62 14 add r9,r9,r12 68: 79 27 00 20 clrldi r7,r9,32 6c: 7d 28 4a 14 add r9,r8,r9 70: 7c 00 38 50 subf r0,r0,r7 74: 78 00 0f e0 rldicl r0,r0,1,63 78: 7c 00 4a 14 add r0,r0,r9 7c: 78 09 00 20 clrldi r9,r0,32 80: 7c 0b 02 14 add r0,r11,r0 84: 7d 08 48 50 subf r8,r8,r9 88: 79 08 0f e0 rldicl r8,r8,1,63 8c: 7d 08 02 14 add r8,r8,r0 90: 79 09 00 20 clrldi r9,r8,32 94: 7d 03 42 14 add r8,r3,r8 98: 7d 2b 48 50 subf r9,r11,r9 9c: 79 29 0f e0 rldicl r9,r9,1,63 a0: 7d 29 42 14 add r9,r9,r8 a4: 79 28 00 20 clrldi r8,r9,32 a8: 7d 2a 4a 14 add r9,r10,r9 ac: 7d 03 40 50 subf r8,r3,r8 b0: 79 08 0f e0 rldicl r8,r8,1,63 b4: 7d 08 4a 14 add r8,r8,r9 b8: 79 09 00 20 clrldi r9,r8,32 bc: 7d 08 2a 14 add r8,r8,r5 c0: 7d 2a 48 50 subf r9,r10,r9 c4: 79 29 0f e0 rldicl r9,r9,1,63 c8: 7d 29 42 14 add r9,r9,r8 cc: 79 2a 00 20 clrldi r10,r9,32 d0: 7d 29 32 14 add r9,r9,r6 d4: 7c a5 50 50 subf r5,r5,r10 d8: 78 a5 0f e0 rldicl r5,r5,1,63 dc: 7d 25 4a 14 add r9,r5,r9 e0: 79 2a 00 20 clrldi r10,r9,32 e4: 7c c6 50 50 subf r6,r6,r10 e8: 78 c6 0f e0 rldicl r6,r6,1,63 ec: 7c c6 4a 14 add r6,r6,r9 f0: 54 c3 80 3e rotlwi r3,r6,16 f4: 7c c6 1a 14 add r6,r6,r3 f8: 7c c3 30 f8 not r3,r6 fc: 78 63 84 22 rldicl r3,r3,48,48 100: 4e 80 00 20 blr Christophe >> >>> --- a/arch/powerpc/lib/checksum_32.S >>> +++ b/arch/powerpc/lib/checksum_32.S >>> @@ -293,3 +293,36 @@ dst_error: >>> EX_TABLE(51b, dst_error); >>> EXPORT_SYMBOL(csum_partial_copy_generic) >>> + >>> +/* >>> + * static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, >>> + * const struct in6_addr *daddr, >>> + * __u32 len, __u8 proto, __wsum sum) >>> + */ >>> + >>> +_GLOBAL(csum_ipv6_magic) >>> + lwz r8, 0(r3) >>> + lwz r9, 4(r3) >>> + lwz r10, 8(r3) >>> + lwz r11, 12(r3) >>> + addc r0, r5, r6 >>> + adde r0, r0, r7 >>> + adde r0, r0, r8 >>> + adde r0, r0, r9 >>> + adde r0, r0, r10 >>> + adde r0, r0, r11 >>> + lwz r8, 0(r4) >>> + lwz r9, 4(r4) >>> + lwz r10, 8(r4) >>> + lwz r11, 12(r4) >>> + adde r0, r0, r8 >>> + adde r0, r0, r9 >>> + adde r0, r0, r10 >>> + adde r0, r0, r11 >>> + addze r0, r0 >>> + rotlwi r3, r0, 16 >>> + add r3, r0, r3 >>> + not r3, r3 >>> + rlwinm r3, r3, 16, 16, 31 >>> + blr >>> +EXPORT_SYMBOL(csum_ipv6_magic) >> >> Clustering the loads and carry insns together is pretty much the worst >> you >> can do on most 32-bit CPUs. > > Oh, really ? __csum_partial is written that way too. > > Right, now I tried interleaving the lwz and adde. I get no improvment at > all on a 885, but I get a 15% improvment on a 8321. > > Christophe > >> >> >> Segher >>
On Thu, May 24, 2018 at 08:20:16AM +0200, Christophe LEROY wrote: > Le 23/05/2018 à 20:34, Segher Boessenkool a écrit : > >On Tue, May 22, 2018 at 08:57:01AM +0200, Christophe Leroy wrote: > >>+_GLOBAL(csum_ipv6_magic) > >>+ lwz r8, 0(r3) > >>+ lwz r9, 4(r3) > >>+ lwz r10, 8(r3) > >>+ lwz r11, 12(r3) > >>+ addc r0, r5, r6 > >>+ adde r0, r0, r7 > >>+ adde r0, r0, r8 > >>+ adde r0, r0, r9 > >>+ adde r0, r0, r10 > >>+ adde r0, r0, r11 > >>+ lwz r8, 0(r4) > >>+ lwz r9, 4(r4) > >>+ lwz r10, 8(r4) > >>+ lwz r11, 12(r4) > >>+ adde r0, r0, r8 > >>+ adde r0, r0, r9 > >>+ adde r0, r0, r10 > >>+ adde r0, r0, r11 > >>+ addze r0, r0 > >>+ rotlwi r3, r0, 16 > >>+ add r3, r0, r3 > >>+ not r3, r3 > >>+ rlwinm r3, r3, 16, 16, 31 > >>+ blr > >>+EXPORT_SYMBOL(csum_ipv6_magic) > > > >Clustering the loads and carry insns together is pretty much the worst you > >can do on most 32-bit CPUs. > > Oh, really ? __csum_partial is written that way too. I thought I told you about this before? Maybe not. > Right, now I tried interleaving the lwz and adde. I get no improvment at > all on a 885, but I get a 15% improvment on a 8321. It won't likely help on single-issue cores (like the one 885 has), yes. Segher
On Thu, May 24, 2018 at 10:18:44AM +0000, Christophe Leroy wrote: > On 05/24/2018 06:20 AM, Christophe LEROY wrote: > >Le 23/05/2018 à 20:34, Segher Boessenkool a écrit : > >>On Tue, May 22, 2018 at 08:57:01AM +0200, Christophe Leroy wrote: > >>>The generic csum_ipv6_magic() generates a pretty bad result > >> > >><snip> > >> > >>Please try with a more recent compiler, what you used is pretty ancient. > >>It's not like recent compilers do great on this either, but it's not > >>*that* bad anymore ;-) > > Here is what I get with GCC 8.1 > It doesn't look much better, does it ? There are no more mfocrf, which is a big speedup. Other than that it is pretty lousy still, I totally agree. This improvement happened quite a while ago, it's fixed in GCC 6. Segher
diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h index 54065caa40b3..a78a57e5058d 100644 --- a/arch/powerpc/include/asm/checksum.h +++ b/arch/powerpc/include/asm/checksum.h @@ -13,6 +13,7 @@ #include <asm-generic/checksum.h> #else #include <linux/bitops.h> +#include <linux/in6.h> /* * Computes the checksum of a memory block at src, length len, * and adds in "sum" (32-bit), while copying the block to dst. @@ -211,6 +212,11 @@ static inline __sum16 ip_compute_csum(const void *buff, int len) return csum_fold(csum_partial(buff, len, 0)); } +#define _HAVE_ARCH_IPV6_CSUM +__sum16 csum_ipv6_magic(const struct in6_addr *saddr, + const struct in6_addr *daddr, + __u32 len, __u8 proto, __wsum sum); + #endif #endif /* __KERNEL__ */ #endif diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S index 9a671c774b22..9167ab088f04 100644 --- a/arch/powerpc/lib/checksum_32.S +++ b/arch/powerpc/lib/checksum_32.S @@ -293,3 +293,36 @@ dst_error: EX_TABLE(51b, dst_error); EXPORT_SYMBOL(csum_partial_copy_generic) + +/* + * static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + * const struct in6_addr *daddr, + * __u32 len, __u8 proto, __wsum sum) + */ + +_GLOBAL(csum_ipv6_magic) + lwz r8, 0(r3) + lwz r9, 4(r3) + lwz r10, 8(r3) + lwz r11, 12(r3) + addc r0, r5, r6 + adde r0, r0, r7 + adde r0, r0, r8 + adde r0, r0, r9 + adde r0, r0, r10 + adde r0, r0, r11 + lwz r8, 0(r4) + lwz r9, 4(r4) + lwz r10, 8(r4) + lwz r11, 12(r4) + adde r0, r0, r8 + adde r0, r0, r9 + adde r0, r0, r10 + adde r0, r0, r11 + addze r0, r0 + rotlwi r3, r0, 16 + add r3, r0, r3 + not r3, r3 + rlwinm r3, r3, 16, 16, 31 + blr +EXPORT_SYMBOL(csum_ipv6_magic) diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S index d7f1a966136e..66900baf5600 100644 --- a/arch/powerpc/lib/checksum_64.S +++ b/arch/powerpc/lib/checksum_64.S @@ -429,3 +429,31 @@ dstnr; stb r6,0(r4) stw r6,0(r8) blr EXPORT_SYMBOL(csum_partial_copy_generic) + +/* + * static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + * const struct in6_addr *daddr, + * __u32 len, __u8 proto, __wsum sum) + */ + +_GLOBAL(csum_ipv6_magic) + ld r8, 0(r3) + ld r9, 8(r3) + add r5, r5, r6 + addc r0, r8, r9 + ld r10, 0(r4) + ld r11, 8(r4) + adde r0, r0, r10 + add r5, r5, r7 + adde r0, r0, r11 + adde r0, r0, r5 + addze r0, r0 + rotldi r3 ,r0, 32 /* fold two 32 bit halves together */ + add r3, r0, r3 + srdi r0, r3, 32 + rotlwi r3, r0, 16 /* fold two 16 bit halves together */ + add r3, r0, r3 + not r3, r3 + rlwinm r3, r3, 16, 16, 31 + blr +EXPORT_SYMBOL(csum_ipv6_magic)
The generic csum_ipv6_magic() generates a pretty bad result 00000000 <csum_ipv6_magic>: (PPC32) 0: 81 23 00 00 lwz r9,0(r3) 4: 81 03 00 04 lwz r8,4(r3) 8: 7c e7 4a 14 add r7,r7,r9 c: 7d 29 38 10 subfc r9,r9,r7 10: 7d 4a 51 10 subfe r10,r10,r10 14: 7d 27 42 14 add r9,r7,r8 18: 7d 2a 48 50 subf r9,r10,r9 1c: 80 e3 00 08 lwz r7,8(r3) 20: 7d 08 48 10 subfc r8,r8,r9 24: 7d 4a 51 10 subfe r10,r10,r10 28: 7d 29 3a 14 add r9,r9,r7 2c: 81 03 00 0c lwz r8,12(r3) 30: 7d 2a 48 50 subf r9,r10,r9 34: 7c e7 48 10 subfc r7,r7,r9 38: 7d 4a 51 10 subfe r10,r10,r10 3c: 7d 29 42 14 add r9,r9,r8 40: 7d 2a 48 50 subf r9,r10,r9 44: 80 e4 00 00 lwz r7,0(r4) 48: 7d 08 48 10 subfc r8,r8,r9 4c: 7d 4a 51 10 subfe r10,r10,r10 50: 7d 29 3a 14 add r9,r9,r7 54: 7d 2a 48 50 subf r9,r10,r9 58: 81 04 00 04 lwz r8,4(r4) 5c: 7c e7 48 10 subfc r7,r7,r9 60: 7d 4a 51 10 subfe r10,r10,r10 64: 7d 29 42 14 add r9,r9,r8 68: 7d 2a 48 50 subf r9,r10,r9 6c: 80 e4 00 08 lwz r7,8(r4) 70: 7d 08 48 10 subfc r8,r8,r9 74: 7d 4a 51 10 subfe r10,r10,r10 78: 7d 29 3a 14 add r9,r9,r7 7c: 7d 2a 48 50 subf r9,r10,r9 80: 81 04 00 0c lwz r8,12(r4) 84: 7c e7 48 10 subfc r7,r7,r9 88: 7d 4a 51 10 subfe r10,r10,r10 8c: 7d 29 42 14 add r9,r9,r8 90: 7d 2a 48 50 subf r9,r10,r9 94: 7d 08 48 10 subfc r8,r8,r9 98: 7d 4a 51 10 subfe r10,r10,r10 9c: 7d 29 2a 14 add r9,r9,r5 a0: 7d 2a 48 50 subf r9,r10,r9 a4: 7c a5 48 10 subfc r5,r5,r9 a8: 7c 63 19 10 subfe r3,r3,r3 ac: 7d 29 32 14 add r9,r9,r6 b0: 7d 23 48 50 subf r9,r3,r9 b4: 7c c6 48 10 subfc r6,r6,r9 b8: 7c 63 19 10 subfe r3,r3,r3 bc: 7c 63 48 50 subf r3,r3,r9 c0: 54 6a 80 3e rotlwi r10,r3,16 c4: 7c 63 52 14 add r3,r3,r10 c8: 7c 63 18 f8 not r3,r3 cc: 54 63 84 3e rlwinm r3,r3,16,16,31 d0: 4e 80 00 20 blr 0000000000000000 <.csum_ipv6_magic>: (PPC64) 0: 81 23 00 00 lwz r9,0(r3) 4: 80 03 00 04 lwz r0,4(r3) 8: 81 63 00 08 lwz r11,8(r3) c: 7c e7 4a 14 add r7,r7,r9 10: 7f 89 38 40 cmplw cr7,r9,r7 14: 7d 47 02 14 add r10,r7,r0 18: 7d 30 10 26 mfocrf r9,1 1c: 55 29 f7 fe rlwinm r9,r9,30,31,31 20: 7d 4a 4a 14 add r10,r10,r9 24: 7f 80 50 40 cmplw cr7,r0,r10 28: 7d 2a 5a 14 add r9,r10,r11 2c: 80 03 00 0c lwz r0,12(r3) 30: 81 44 00 00 lwz r10,0(r4) 34: 7d 10 10 26 mfocrf r8,1 38: 55 08 f7 fe rlwinm r8,r8,30,31,31 3c: 7d 29 42 14 add r9,r9,r8 40: 81 04 00 04 lwz r8,4(r4) 44: 7f 8b 48 40 cmplw cr7,r11,r9 48: 7d 29 02 14 add r9,r9,r0 4c: 7d 70 10 26 mfocrf r11,1 50: 55 6b f7 fe rlwinm r11,r11,30,31,31 54: 7d 29 5a 14 add r9,r9,r11 58: 7f 80 48 40 cmplw cr7,r0,r9 5c: 7d 29 52 14 add r9,r9,r10 60: 7c 10 10 26 mfocrf r0,1 64: 54 00 f7 fe rlwinm r0,r0,30,31,31 68: 7d 69 02 14 add r11,r9,r0 6c: 7f 8a 58 40 cmplw cr7,r10,r11 70: 7c 0b 42 14 add r0,r11,r8 74: 81 44 00 08 lwz r10,8(r4) 78: 7c f0 10 26 mfocrf r7,1 7c: 54 e7 f7 fe rlwinm r7,r7,30,31,31 80: 7c 00 3a 14 add r0,r0,r7 84: 7f 88 00 40 cmplw cr7,r8,r0 88: 7d 20 52 14 add r9,r0,r10 8c: 80 04 00 0c lwz r0,12(r4) 90: 7d 70 10 26 mfocrf r11,1 94: 55 6b f7 fe rlwinm r11,r11,30,31,31 98: 7d 29 5a 14 add r9,r9,r11 9c: 7f 8a 48 40 cmplw cr7,r10,r9 a0: 7d 29 02 14 add r9,r9,r0 a4: 7d 70 10 26 mfocrf r11,1 a8: 55 6b f7 fe rlwinm r11,r11,30,31,31 ac: 7d 29 5a 14 add r9,r9,r11 b0: 7f 80 48 40 cmplw cr7,r0,r9 b4: 7d 29 2a 14 add r9,r9,r5 b8: 7c 10 10 26 mfocrf r0,1 bc: 54 00 f7 fe rlwinm r0,r0,30,31,31 c0: 7d 29 02 14 add r9,r9,r0 c4: 7f 85 48 40 cmplw cr7,r5,r9 c8: 7c 09 32 14 add r0,r9,r6 cc: 7d 50 10 26 mfocrf r10,1 d0: 55 4a f7 fe rlwinm r10,r10,30,31,31 d4: 7c 00 52 14 add r0,r0,r10 d8: 7f 80 30 40 cmplw cr7,r0,r6 dc: 7d 30 10 26 mfocrf r9,1 e0: 55 29 ef fe rlwinm r9,r9,29,31,31 e4: 7c 09 02 14 add r0,r9,r0 e8: 54 03 80 3e rotlwi r3,r0,16 ec: 7c 03 02 14 add r0,r3,r0 f0: 7c 03 00 f8 not r3,r0 f4: 78 63 84 22 rldicl r3,r3,48,48 f8: 4e 80 00 20 blr This patch implements it in assembly for both PPC32 and PPC64 Link: https://github.com/linuxppc/linux/issues/9 Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> --- v3: Add support for PPC64 (please review, especially whether instructions order in optimal) v2: Fix number of args in final addze arch/powerpc/include/asm/checksum.h | 6 ++++++ arch/powerpc/lib/checksum_32.S | 33 +++++++++++++++++++++++++++++++++ arch/powerpc/lib/checksum_64.S | 28 ++++++++++++++++++++++++++++ 3 files changed, 67 insertions(+)