Messages in this thread | | | Date | Sat, 10 Jul 2021 14:31:09 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH v2 0/3] lib/string: optimized mem* functions |
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On Fri, 2 Jul 2021 14:31:50 +0200 Matteo Croce <mcroce@linux.microsoft.com> wrote:
> From: Matteo Croce <mcroce@microsoft.com> > > Rewrite the generic mem{cpy,move,set} so that memory is accessed with > the widest size possible, but without doing unaligned accesses. > > This was originally posted as C string functions for RISC-V[1], but as > there was no specific RISC-V code, it was proposed for the generic > lib/string.c implementation. > > Tested on RISC-V and on x86_64 by undefining __HAVE_ARCH_MEM{CPY,SET,MOVE} > and HAVE_EFFICIENT_UNALIGNED_ACCESS. > > These are the performances of memcpy() and memset() of a RISC-V machine > on a 32 mbyte buffer: > > memcpy: > original aligned: 75 Mb/s > original unaligned: 75 Mb/s > new aligned: 114 Mb/s > new unaligned: 107 Mb/s > > memset: > original aligned: 140 Mb/s > original unaligned: 140 Mb/s > new aligned: 241 Mb/s > new unaligned: 241 Mb/s
Did you record the x86_64 performance?
Which other architectures are affected by this change?
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