Re: [PATCH 0/3] Get cache information from userland

[Zong Li]

On Fri, Aug 21, 2020 at 4:45 AM Palmer Dabbelt <palmer@xxxxxxxxxxx> wrote:
>
> On Fri, 03 Jul 2020 01:57:52 PDT (-0700), zong.li@xxxxxxxxxx wrote:
> > There are no standard CSR registers to provide cache information, the
> > way for RISC-V is to get this information from DT. Currently, AT_L1I_X,
> > AT_L1D_X and AT_L2_X are present in glibc header, and sysconf syscall
> > could use them to get information of cache through AUX vector. We
> > exploit 'struct cacheinfo' to obtain the information of cache, then we
> > don't need additional variable or data structure to record it.
> >
> > We also need some works in glibc, but we have to support the function in
> > kernel first by rule of glibc, then post the patch to glibc site.
> >
> > The result of 'getconf -a' as follows:
> >
> > LEVEL1_ICACHE_SIZE                 32768
> > LEVEL1_ICACHE_ASSOC                8
> > LEVEL1_ICACHE_LINESIZE             64
> > LEVEL1_DCACHE_SIZE                 32768
> > LEVEL1_DCACHE_ASSOC                8
> > LEVEL1_DCACHE_LINESIZE             64
> > LEVEL2_CACHE_SIZE                  2097152
> > LEVEL2_CACHE_ASSOC                 32
> > LEVEL2_CACHE_LINESIZE              64
> >
> > Zong Li (3):
> >   riscv: Set more data to cacheinfo
> >   riscv: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO
> >   riscv: Add cache information in AUX vector
> >
> >  arch/riscv/include/asm/cacheinfo.h   | 14 +++++
> >  arch/riscv/include/asm/elf.h         | 13 ++++
> >  arch/riscv/include/uapi/asm/auxvec.h | 24 ++++++++
> >  arch/riscv/kernel/cacheinfo.c        | 92 +++++++++++++++++++++++-----
> >  4 files changed, 127 insertions(+), 16 deletions(-)
> >  create mode 100644 arch/riscv/include/asm/cacheinfo.h
>
> Sorry, I lost track of these.  There's a little issue in #1, LMK if you want to
> send another version or if you want me to just fix it.

Sorry for being late here, I have sent the second version patches to
fix it, thanks for your reviewing.