[PATCH] powerpc/pseries: Provide verbose info about HPT resizing attempt

[Michael Ellerman]

Bharata B Rao <bharata at linux.ibm.com> writes:

> When HPT resizing is attempted in response to memory hotplug, we see
> the following messages from the kernel:
>
> lpar: Attempting to resize HPT to shift 23
> Unable to resize hash page table to target order 23: -28
>
> This gives a feeling as though we are trying to grow HPT but failed and
> hence bad things might happen in future. Improve the message a bit
> by explicitly printing the existing HPT shift value in addtion to
> the newly targeted value so that it is clear that we haven't failed
> to grow HPT. After this commit, the same message will appear like this:
>
> lpar: Attempting to resize HPT from shift 25 to 23
> Unable to resize hash page table to target order 23: -28
>
> Signed-off-by: Bharata B Rao <bharata at linux.ibm.com>

I'd be inclined to just remove the "Attempting .." message.

But I have this patch from Laurent queued, which already reworks things:

  https://patchwork.ozlabs.org/patch/1055996/


Does that address your problem?

cheers

> diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
> index f2a9f0adc2d3..ecc7fa1876a9 100644
> --- a/arch/powerpc/platforms/pseries/lpar.c
> +++ b/arch/powerpc/platforms/pseries/lpar.c
> @@ -875,7 +875,8 @@ static int pseries_lpar_resize_hpt(unsigned long shift)
>  	if (!firmware_has_feature(FW_FEATURE_HPT_RESIZE))
>  		return -ENODEV;
>  
> -	pr_info("Attempting to resize HPT to shift %lu\n", shift);
> +	pr_info("Attempting to resize HPT from shift %llu to %lu\n", ppc64_pft_size,
> +		shift);
>  
>  	t0 = ktime_get();
>  
> -- 
> 2.17.1