Messages in this thread | | | Date | Thu, 10 Dec 2020 11:04:54 +0100 | From | Oscar Salvador <> | Subject | Re: [PATCH v8 09/12] mm/hugetlb: Add a kernel parameter hugetlb_free_vmemmap |
| |
On Thu, Dec 10, 2020 at 11:55:23AM +0800, Muchun Song wrote: > +hugetlb_free_vmemmap > + When CONFIG_HUGETLB_PAGE_FREE_VMEMMAP is set, this enables freeing > + unused vmemmap pages associated each HugeTLB page. ^^^ with
> - if (end - start < PAGES_PER_SECTION * sizeof(struct page)) > + if (is_hugetlb_free_vmemmap_enabled()) > + err = vmemmap_populate_basepages(start, end, node, NULL); > + else if (end - start < PAGES_PER_SECTION * sizeof(struct page)) > err = vmemmap_populate_basepages(start, end, node, NULL);
Not sure if joining those in an OR makes se.se
> else if (boot_cpu_has(X86_FEATURE_PSE)) > err = vmemmap_populate_hugepages(start, end, node, altmap); > @@ -1610,7 +1613,8 @@ void register_page_bootmem_memmap(unsigned long section_nr, > } > get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO); > > - if (!boot_cpu_has(X86_FEATURE_PSE)) { > + if (!boot_cpu_has(X86_FEATURE_PSE) || > + is_hugetlb_free_vmemmap_enabled()) {
I would add a variable at the beginning called "basepages_populated" that holds the result of those two conditions. I am not sure if it slightly improves the code as the conditions do not need to be rechecked, but the readibility a bit.
> +bool hugetlb_free_vmemmap_enabled; > + > +static int __init early_hugetlb_free_vmemmap_param(char *buf) > +{ > + if (!buf) > + return -EINVAL; > + > + /* We cannot optimize if a "struct page" crosses page boundaries. */
I think this comment belongs to the last patch.
-- Oscar Salvador SUSE L3
| |