Re: [PATCH v5 3/9] mm/mmu_notifier: convert mmu_notifier_range->blockable to a flags

[Ralph Campbell]

On 2/19/19 12:04 PM, jglisse@xxxxxxxxxx wrote:
> From: JÃrÃme Glisse <jglisse@xxxxxxxxxx>
>
> Use an unsigned field for flags other than blockable and convert
> the blockable field to be one of those flags.
>
> Signed-off-by: JÃrÃme Glisse <jglisse@xxxxxxxxxx>
> Cc: Christian KÃnig <christian.koenig@xxxxxxx>
> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
> Cc: Jan Kara <jack@xxxxxxx>
> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
> Cc: Peter Xu <peterx@xxxxxxxxxx>
> Cc: Felix Kuehling <Felix.Kuehling@xxxxxxx>
> Cc: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Ross Zwisler <zwisler@xxxxxxxxxx>
> Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxxxx>
> Cc: Christian Koenig <christian.koenig@xxxxxxx>
> Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
> Cc: John Hubbard <jhubbard@xxxxxxxxxx>
> Cc: kvm@xxxxxxxxxxxxxxx
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Cc: linux-rdma@xxxxxxxxxxxxxxx
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>   include/linux/mmu_notifier.h | 11 +++++++----
>   1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
> index e630def131ce..c8672c366f67 100644
> --- a/include/linux/mmu_notifier.h
> +++ b/include/linux/mmu_notifier.h
> @@ -25,11 +25,13 @@ struct mmu_notifier_mm {
>   	spinlock_t lock;
>   };
>   
> +#define MMU_NOTIFIER_RANGE_BLOCKABLE (1 << 0)
> +
>   struct mmu_notifier_range {
>   	struct mm_struct *mm;
>   	unsigned long start;
>   	unsigned long end;
> -	bool blockable;
> +	unsigned flags;
>   };
>   
>   struct mmu_notifier_ops {
> @@ -229,7 +231,7 @@ extern void __mmu_notifier_invalidate_range(struct mm_struct *mm,
>   static inline bool
>   mmu_notifier_range_blockable(const struct mmu_notifier_range *range)
>   {
> -	return range->blockable;
> +	return (range->flags & MMU_NOTIFIER_RANGE_BLOCKABLE);
>   }
>   
>   static inline void mmu_notifier_release(struct mm_struct *mm)
> @@ -275,7 +277,7 @@ static inline void
>   mmu_notifier_invalidate_range_start(struct mmu_notifier_range *range)
>   {
>   	if (mm_has_notifiers(range->mm)) {
> -		range->blockable = true;
> +		range->flags |= MMU_NOTIFIER_RANGE_BLOCKABLE;
>   		__mmu_notifier_invalidate_range_start(range);
>   	}
>   }
> @@ -284,7 +286,7 @@ static inline int
>   mmu_notifier_invalidate_range_start_nonblock(struct mmu_notifier_range *range)
>   {
>   	if (mm_has_notifiers(range->mm)) {
> -		range->blockable = false;
> +		range->flags &= ~MMU_NOTIFIER_RANGE_BLOCKABLE;
>   		return __mmu_notifier_invalidate_range_start(range);
>   	}
>   	return 0;
> @@ -331,6 +333,7 @@ static inline void mmu_notifier_range_init(struct mmu_notifier_range *range,
>   	range->mm = mm;
>   	range->start = start;
>   	range->end = end;
> +	range->flags = 0;
>   }
>   
>   #define ptep_clear_flush_young_notify(__vma, __address, __ptep)		\

Reviewed-by: Ralph Campbell <rcampbell@xxxxxxxxxx>