Re: [PATCH v3 3/8] drivers/base/memory: store mapping between MMOP_* and string in an array

[David Hildenbrand]

On 20.03.20 08:36, Baoquan He wrote:
> On 03/19/20 at 02:12pm, David Hildenbrand wrote:
>> Let's use a simple array which we can reuse soon. While at it, move the
>> string->mmop conversion out of the device hotplug lock.
>>
>> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx>
>> Acked-by: Michal Hocko <mhocko@xxxxxxxx>
>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
>> Cc: Michal Hocko <mhocko@xxxxxxxxxx>
>> Cc: Oscar Salvador <osalvador@xxxxxxx>
>> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
>> Cc: Baoquan He <bhe@xxxxxxxxxx>
>> Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
>> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
>> ---
>>  drivers/base/memory.c | 38 +++++++++++++++++++++++---------------
>>  1 file changed, 23 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
>> index e7e77cafef80..8a7f29c0bf97 100644
>> --- a/drivers/base/memory.c
>> +++ b/drivers/base/memory.c
>> @@ -28,6 +28,24 @@
>>  
>>  #define MEMORY_CLASS_NAME	"memory"
>>  
>> +static const char *const online_type_to_str[] = {
>> +	[MMOP_OFFLINE] = "offline",
>> +	[MMOP_ONLINE] = "online",
>> +	[MMOP_ONLINE_KERNEL] = "online_kernel",
>> +	[MMOP_ONLINE_MOVABLE] = "online_movable",
>> +};
>> +
>> +static int memhp_online_type_from_str(const char *str)
>> +{
>> +	int i;
> 
> I would change it as: 
> 
> 	for (int i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
> 

That's not allowed by the C90 standard (and -std=gnu89).

$ gcc main.c -std=gnu89
main.c: In function 'main':
main.c:3:2: error: 'for' loop initial declarations are only allowed in
C99 or C11 mode
    3 |  for (int i = 0; i < 8; i++) {
      |  ^~~

One of the reasons why
	git grep "for (int "

will result in very little hits (IOW, only 5 in driver code only).

-- 
Thanks,

David / dhildenb