[v2,0/3] RISC-V: Export Zba, Zbb to usermode via hwprobe

Message

Evan Green May 9, 2023, 6:25 p.m. UTC

This change detects the presence of Zba, Zbb, and Zbs extensions and exports
them per-hart to userspace via the hwprobe mechanism. Glibc can then use
these in setting up hwcaps-based library search paths.

There's a little bit of extra housekeeping here: the first change adds
Zba and Zbs to the set of extensions the kernel recognizes, and the second
change starts tracking ISA features per-hart (in addition to the ANDed
mask of features across all harts which the kernel uses to make
decisions). Now that we track the ISA information per-hart, we could
even fix up /proc/cpuinfo to accurately report extension per-hart,
though I've left that out of this series for now.

Changes in v2:
 - Add Zbs as well
 - Add blank line before if in riscv_fill_hwcap() (Conor)
 - Fixed typo s/supporte/supported/ (Conor)
 - Fixed copypasta s/IMA_ZBB/EXT_ZBB/ (Conor)
 - Added Zbs

Evan Green (3):
  RISC-V: Add Zba, Zbs extension probing
  RISC-V: Track ISA extensions per hart
  RISC-V: hwprobe: Expose Zba, Zbb, and Zbs

 Documentation/riscv/hwprobe.rst       | 10 ++++++
 arch/riscv/include/asm/cpufeature.h   | 10 ++++++
 arch/riscv/include/asm/hwcap.h        |  2 ++
 arch/riscv/include/uapi/asm/hwprobe.h |  3 ++
 arch/riscv/kernel/cpu.c               |  2 ++
 arch/riscv/kernel/cpufeature.c        | 20 +++++++----
 arch/riscv/kernel/sys_riscv.c         | 48 +++++++++++++++++++++++----
 7 files changed, 82 insertions(+), 13 deletions(-)

Comments

Palmer Dabbelt June 19, 2023, 10:07 p.m. UTC | #1

On Tue, 09 May 2023 11:25:00 -0700, Evan Green wrote:
> This change detects the presence of Zba, Zbb, and Zbs extensions and exports
> them per-hart to userspace via the hwprobe mechanism. Glibc can then use
> these in setting up hwcaps-based library search paths.
> 
> There's a little bit of extra housekeeping here: the first change adds
> Zba and Zbs to the set of extensions the kernel recognizes, and the second
> change starts tracking ISA features per-hart (in addition to the ANDed
> mask of features across all harts which the kernel uses to make
> decisions). Now that we track the ISA information per-hart, we could
> even fix up /proc/cpuinfo to accurately report extension per-hart,
> though I've left that out of this series for now.
> 
> [...]

Applied, thanks!

[1/3] RISC-V: Add Zba, Zbs extension probing
      https://git.kernel.org/palmer/c/c6699baf1064
[2/3] RISC-V: Track ISA extensions per hart
      https://git.kernel.org/palmer/c/82e9c66e81c8
[3/3] RISC-V: hwprobe: Expose Zba, Zbb, and Zbs
      https://git.kernel.org/palmer/c/c0baf321038d

Best regards,

[e-mail] June 20, 2023, 1 a.m. UTC | #2

Hello:

This series was applied to riscv/linux.git (for-next)
by Palmer Dabbelt <[e-mail]>:

On Tue,  9 May 2023 11:25:00 -0700 you wrote:
> This change detects the presence of Zba, Zbb, and Zbs extensions and exports
> them per-hart to userspace via the hwprobe mechanism. Glibc can then use
> these in setting up hwcaps-based library search paths.
> 
> There's a little bit of extra housekeeping here: the first change adds
> Zba and Zbs to the set of extensions the kernel recognizes, and the second
> change starts tracking ISA features per-hart (in addition to the ANDed
> mask of features across all harts which the kernel uses to make
> decisions). Now that we track the ISA information per-hart, we could
> even fix up /proc/cpuinfo to accurately report extension per-hart,
> though I've left that out of this series for now.
> 
> [...]

Here is the summary with links:
  - [v2,1/3] RISC-V: Add Zba, Zbs extension probing
    https://git.kernel.org/riscv/c/c6699baf1064
  - [v2,2/3] RISC-V: Track ISA extensions per hart
    https://git.kernel.org/riscv/c/82e9c66e81c8
  - [v2,3/3] RISC-V: hwprobe: Expose Zba, Zbb, and Zbs
    https://git.kernel.org/riscv/c/c0baf321038d

You are awesome, thank you!