[PATCH] powerpc/mm: Use VM_WARN_ONCE() for irqs disabled check

[Aneesh Kumar K.V]

Michael Ellerman <mpe at ellerman.id.au> writes:

> The check for !arch_irqs_disabled() in find_linux_pte_or_hugepte() is a
> debugging aid, and needn't be enabled for production builds.
>
> Switch it to a VM_WARN_ONCE(), which is compiled out when
> CONFIG_DEBUG_VM=n.
>
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
> ---
>  arch/powerpc/include/asm/pgtable.h | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
> index ee09e99097f0..651848039dc4 100644
> --- a/arch/powerpc/include/asm/pgtable.h
> +++ b/arch/powerpc/include/asm/pgtable.h
> @@ -71,10 +71,8 @@ pte_t *__find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
>  static inline pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
>  					       bool *is_thp, unsigned *shift)
>  {
> -	if (!arch_irqs_disabled()) {
> -		pr_info("%s called with irq enabled\n", __func__);
> -		dump_stack();
> -	}
> +	VM_WARN_ONCE(!arch_irqs_disabled(),
> +		     "find_linux_pte_or_hugepte() called with irqs enabled!\n");
>  	return __find_linux_pte_or_hugepte(pgdir, ea, is_thp, shift);
>  }
>


https://lkml.kernel.org/r/574de240.uG8/5OM2Lu9RY6K+%akpm@linux-foundation.orgdd

Isn't this patch already part of -mm. And why ONCE, we want to find
about all the wrong usage.

-aneesh