Re: [PATCH v2 1/2] powerpc/perf: Use stack siar instead of mfspr

[kajoljain <kjain@linux.ibm.com>]

On 8/13/21 1:54 PM, Kajol Jain wrote:
> Minor optimization in the 'perf_instruction_pointer' function code by
> making use of stack siar instead of mfspr.
> 
> Fixes: 75382aa72f06 ("powerpc/perf: Move code to select SIAR or pt_regs
> into perf_read_regs")
> Signed-off-by: Kajol Jain <kjain@linux.ibm.com>

Please ignore this patch-set as I mentioned wrong version number. I will resend
this patch-set again with correct version. Sorry for the confusion.

Thanks,
Kajol Jain
> ---
>  arch/powerpc/perf/core-book3s.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
> index bb0ee716de91..1b464aad29c4 100644
> --- a/arch/powerpc/perf/core-book3s.c
> +++ b/arch/powerpc/perf/core-book3s.c
> @@ -2260,7 +2260,7 @@ unsigned long perf_instruction_pointer(struct pt_regs *regs)
>  		else
>  			return regs->nip;
>  	} else if (use_siar && siar_valid(regs))
> -		return mfspr(SPRN_SIAR) + perf_ip_adjust(regs);
> +		return siar + perf_ip_adjust(regs);
>  	else if (use_siar)
>  		return 0;		// no valid instruction pointer
>  	else
>