Re: [PATCH -mm -v7 4/9] mm, THP, swap: Add get_huge_swap_page()

From: Huang\, Ying
Date: Fri Mar 31 2017 - 23:33:12 EST


Johannes Weiner <hannes@xxxxxxxxxxx> writes:

> On Thu, Mar 30, 2017 at 12:28:17PM +0800, Huang, Ying wrote:
>> Johannes Weiner <hannes@xxxxxxxxxxx> writes:
>> > On Tue, Mar 28, 2017 at 01:32:04PM +0800, Huang, Ying wrote:
>> >> @@ -527,6 +527,23 @@ static inline swp_entry_t get_swap_page(void)
>> >>
>> >> #endif /* CONFIG_SWAP */
>> >>
>> >> +#ifdef CONFIG_THP_SWAP_CLUSTER
>> >> +static inline swp_entry_t get_huge_swap_page(void)
>> >> +{
>> >> + swp_entry_t entry;
>> >> +
>> >> + if (get_swap_pages(1, &entry, true))
>> >> + return entry;
>> >> + else
>> >> + return (swp_entry_t) {0};
>> >> +}
>> >> +#else
>> >> +static inline swp_entry_t get_huge_swap_page(void)
>> >> +{
>> >> + return (swp_entry_t) {0};
>> >> +}
>> >> +#endif
>> >
>> > Your introducing a function without a user, making it very hard to
>> > judge whether the API is well-designed for the callers or not.
>> >
>> > I pointed this out as a systemic problem with this patch series in v3,
>> > along with other stuff, but with the way this series is structured I'm
>> > having a hard time seeing whether you implemented my other feedback or
>> > whether your counter arguments to them are justified.
>> >
>> > I cannot review and ack these patches this way.
>>
>> Sorry for inconvenience, I will send a new version to combine the
>> function definition and usage into one patch at least for you to
>> review.
>
> We tried this before. I reviewed the self-contained patch and you
> incorporated the feedback into the split-out structure that made it
> impossible for me to verify the updates.
>
> I'm not sure why you insist on preserving this series format. It's not
> good for review, and it's not good for merging and git history.

I had thought some reviewers would prefer the original series format.
But I will use your suggested format in the future, unless more
reviewers prefer the original format.

Best Regards,
Huang, Ying

>> But I think we can continue our discussion in the comments your
>> raised so far firstly, what do you think about that?
>
> Yeah, let's finish the discussions before -v8.