Re: [v3 PATCH 2/8] RISC-V: Move cpuid to hartid mapping to SMP.

[Christoph Hellwig <hch@infradead.org>]

On Thu, Feb 07, 2019 at 05:51:15PM -0800, Atish Patra wrote:
> Currently, logical CPU id to physical hartid mapping is
> defined for both smp and non-smp configurations. This
> is not required as we need this only for smp configuration.
> The mapping function can define directly boot_cpu_hartid
> for non-smp use case.

Please use up your available 72 chars for the changelog.  (probably also
in other patches).

> 
> The reverse mapping function i.e. hartid to cpuid can be called
> for any valid but not booted harts. So it should return default
> cpu 0 only if it is a boot hartid.
> 
> Signed-off-by: Atish Patra <atish.patra@wdc.com>
> Reviewed-by: Anup Patel <anup@brainfault.org>
> ---
>  arch/riscv/include/asm/smp.h | 14 +++++++++++---
>  arch/riscv/kernel/setup.c    |  9 ---------
>  arch/riscv/kernel/smp.c      |  9 +++++++++
>  3 files changed, 20 insertions(+), 12 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
> index 41aa73b4..21fd2d75 100644
> --- a/arch/riscv/include/asm/smp.h
> +++ b/arch/riscv/include/asm/smp.h
> @@ -22,12 +22,13 @@
>  /*
>   * Mapping between linux logical cpu index and hartid.
>   */
> -extern unsigned long __cpuid_to_hartid_map[NR_CPUS];
> -#define cpuid_to_hartid_map(cpu)    __cpuid_to_hartid_map[cpu]
>  
> +extern unsigned long boot_cpu_hartid;
>  struct seq_file;

We usually try to keep forward declatations at the top of the file.

Can you add the new external declaration below the forward one?

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>