[Skiboot] [PATCH] Adjust skiboot_cpu_stacks region size according to real max PIR

[Benjamin Herrenschmidt]

Cosmetic comments only:

> diff --git a/core/init.c b/core/init.c
> index 445272a..0e91a9d 100644
> --- a/core/init.c
> +++ b/core/init.c
> @@ -634,6 +634,8 @@ void __noreturn main_cpu_entry(const void *fdt, u32 master_cpu)
>  
>  	/* Initialize the rest of the cpu thread structs */
>  	init_all_cpus();
> +	/* We now know real max PIR, so adjust mem region appropriately */
> +	adjust_cpu_stacks_len_to_max_pir();

I like having a blank line between comment+function :-)

Also I tend to dislike enormous_function_names_from_hell().

What about adjust_cpu_stacks_alloc() ?

>  	/* Allocate our split trace buffers now. Depends add_opal_node() */
>  	init_trace_buffers();
> diff --git a/core/mem_region.c b/core/mem_region.c
> index 5a496aa..569f8fd 100644
> --- a/core/mem_region.c
> +++ b/core/mem_region.c
> @@ -725,6 +725,15 @@ struct mem_region *find_mem_region(const char *name)
>  	return NULL;
>  }
>  
> +void adjust_cpu_stacks_len_to_max_pir(void)
> +{
> +	/* CPU stacks start at 0, then when we know max possible PIR,
> +	 * we adjust, then when we bring all CPUs online we know the
> +	 * runtime max PIR, so we adjust this a few times during boot.
> +	 */
> +	skiboot_cpu_stacks.len = (cpu_max_pir + 1) * STACK_SIZE;
> +}
> +
>  /* Trawl through device tree, create memory regions from nodes. */
>  void mem_region_init(void)
>  {
> @@ -773,8 +782,7 @@ void mem_region_init(void)
>  		unlock(&mem_region_lock);
>  	}
>  
> -	/* Now we know how many CPU stacks we have, fix that up. */
> -	skiboot_cpu_stacks.len = (cpu_max_pir + 1) * STACK_SIZE;
> +	adjust_cpu_stacks_len_to_max_pir();

In fact the comment used to be right... it's just that I later on
shuffled things around and made the mem region init happen earlier ...

>  	lock(&mem_region_lock);
>  
> diff --git a/include/mem_region.h b/include/mem_region.h
> index 23ee18c..96dfddc 100644
> --- a/include/mem_region.h
> +++ b/include/mem_region.h
> @@ -60,7 +60,7 @@ void mem_region_release_unused(void);
>  extern struct mem_region skiboot_heap;
>  
>  void mem_region_init(void);
> -
> +void adjust_cpu_stacks_len_to_max_pir(void);
>  void mem_region_add_dt_reserved(void);
>  
>  /* Mark memory as reserved */