[PATCH] mm: use CPU_BITS_NONE to initialize init_mm.cpu_bitmask

[PATCH] mm: use CPU_BITS_NONE to initialize init_mm.cpu_bitmask

[Mike Rapoport]

Replace open-coded bitmap array initialization of init_mm.cpu_bitmask with
neat CPU_BITS_NONE macro.

And, since init_mm.cpu_bitmask is statically set to zero, there is no way
to clear it again in start_kernel().

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
---
 init/main.c  | 1 -
 mm/init-mm.c | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/init/main.c b/init/main.c
index 96f8d5a..e29becc 100644
--- a/init/main.c
+++ b/init/main.c
@@ -594,7 +594,6 @@ asmlinkage __visible void __init start_kernel(void)
 	page_address_init();
 	pr_notice("%s", linux_banner);
 	setup_arch(&command_line);
-	mm_init_cpumask(&init_mm);
 	setup_command_line(command_line);
 	setup_nr_cpu_ids();
 	setup_per_cpu_areas();
diff --git a/mm/init-mm.c b/mm/init-mm.c
index a787a31..fb1e150 100644
--- a/mm/init-mm.c
+++ b/mm/init-mm.c
@@ -35,6 +35,6 @@ struct mm_struct init_mm = {
 	.arg_lock	=  __SPIN_LOCK_UNLOCKED(init_mm.arg_lock),
 	.mmlist		= LIST_HEAD_INIT(init_mm.mmlist),
 	.user_ns	= &init_user_ns,
-	.cpu_bitmap	= { [BITS_TO_LONGS(NR_CPUS)] = 0},
+	.cpu_bitmap	= CPU_BITS_NONE,
 	INIT_MM_CONTEXT(init_mm)
 };
-- 
2.7.4

Re: [PATCH] mm: use CPU_BITS_NONE to initialize init_mm.cpu_bitmask

[David Hildenbrand]

On 13.08.19 15:43, Mike Rapoport wrote:
> Replace open-coded bitmap array initialization of init_mm.cpu_bitmask with
> neat CPU_BITS_NONE macro.
> 
> And, since init_mm.cpu_bitmask is statically set to zero, there is no way
> to clear it again in start_kernel().
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
>  init/main.c  | 1 -
>  mm/init-mm.c | 2 +-
>  2 files changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/init/main.c b/init/main.c
> index 96f8d5a..e29becc 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -594,7 +594,6 @@ asmlinkage __visible void __init start_kernel(void)
>  	page_address_init();
>  	pr_notice("%s", linux_banner);
>  	setup_arch(&command_line);
> -	mm_init_cpumask(&init_mm);
>  	setup_command_line(command_line);
>  	setup_nr_cpu_ids();
>  	setup_per_cpu_areas();
> diff --git a/mm/init-mm.c b/mm/init-mm.c
> index a787a31..fb1e150 100644
> --- a/mm/init-mm.c
> +++ b/mm/init-mm.c
> @@ -35,6 +35,6 @@ struct mm_struct init_mm = {
>  	.arg_lock	=  __SPIN_LOCK_UNLOCKED(init_mm.arg_lock),
>  	.mmlist		= LIST_HEAD_INIT(init_mm.mmlist),
>  	.user_ns	= &init_user_ns,
> -	.cpu_bitmap	= { [BITS_TO_LONGS(NR_CPUS)] = 0},
> +	.cpu_bitmap	= CPU_BITS_NONE,
>  	INIT_MM_CONTEXT(init_mm)
>  };
> 

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 

Thanks,

David / dhildenb