Re: [PATCH v2 2/7] mm/swapfile.c: Replace some #ifdef with IS_ENABLED()

[Huang\, Ying]

Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> writes:

> On 07/17/2018 08:25 PM, Huang, Ying wrote:
>>> Seriously, though, does it hurt us to add a comment or two to say
>>> something like:
>>>
>>> 	/*
>>> 	 * Should not even be attempting cluster allocations when
>>> 	 * huge page swap is disabled.  Warn and fail the allocation.
>>> 	 */
>>> 	if (!IS_ENABLED(CONFIG_THP_SWAP)) {
>>> 		VM_WARN_ON_ONCE(1);
>>> 		return 0;
>>> 	}
>> I totally agree with you that we should add more comments for THP swap
>> to improve the code readability.  As for this specific case,
>> VM_WARN_ON_ONCE() here is just to capture some programming error during
>> development.  Do we really need comments here?
>
> If it's code in mainline, we need to know what it is doing.
>
> If it's not useful to have in mainline, then let's remove it.

OK.  Will add the comments.

Best Regards,
Huang, Ying