On 04.04.22 09:46, Muchun Song wrote:
> The word of "free" is not expressive enough to express the feature of optimizing
> vmemmap pages associated with each HugeTLB, rename this keywork to "optimeze".
> And some function names are prefixed with "huge_page" instead of "hugetlb", it is
> easily to be confused with THP. In this patch , cheanup related functions to make
> code more clear and expressive.
No strong opinion (I remember I kicked of the discussion), but I was
wondering if instead of alloc vs. free we could be using something like
optimize vs. restore/rollback.
E.g., hugetlb_vmemmap_optimize() vs. hugetlb_vmemmap_restore().
Maybe there are other suggestions?
>
> Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
> ---
> include/linux/hugetlb.h | 2 +-
> mm/hugetlb.c | 10 +++++-----
> mm/hugetlb_vmemmap.c | 42 ++++++++++++++++++++----------------------
> mm/hugetlb_vmemmap.h | 20 ++++++++++----------
> 4 files changed, 36 insertions(+), 38 deletions(-)
>
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index 53c1b6082a4c..c16fbb1228a3 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -618,7 +618,7 @@ struct hstate {
> unsigned int free_huge_pages_node[MAX_NUMNODES];
> unsigned int surplus_huge_pages_node[MAX_NUMNODES];
> #ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP
> - unsigned int nr_free_vmemmap_pages;
> + unsigned int optimize_vmemmap_pages;
I suggest converting that into a bool and just calling it
"bool optimize_vmemmap_pages".
You can easily compute what hugetlb_vmemmap_init() at runtime from the
page and RESERVE_VMEMMAP_NR, right?
At least the calculation in alloc_huge_page_vmemmap() and
free_huge_page_vmemmap() become *less* weird for me if the magic value
RESERVE_VMEMMAP_NR isn't used explicitly for vmemmap_addr but implicitly
for vmemmap_end.
> #endif
> #ifdef CONFIG_CGROUP_HUGETLB
> /* cgroup control files */
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index dd642cfc538b..1f9fbdddc86b 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -1540,7 +1540,7 @@ static void __update_and_free_page(struct hstate *h, struct page *page)
> if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
> return;
>
> - if (alloc_huge_page_vmemmap(h, page)) {
> + if (hugetlb_vmemmap_alloc(h, page)) {
> spin_lock_irq(&hugetlb_lock);
> /*
> * If we cannot allocate vmemmap pages, just refuse to free the
> @@ -1617,7 +1617,7 @@ static DECLARE_WORK(free_hpage_work, free_hpage_workfn);
>
> static inline void flush_free_hpage_work(struct hstate *h)
> {
> - if (free_vmemmap_pages_per_hpage(h))
> + if (hugetlb_optimize_vmemmap_pages(h))
It might be reasonable to call that hugetlb_should_optimize_vmemmap()
then, letting it return a bool.
--
Thanks,
David / dhildenb
