• Atsushi Kumagai's avatar
    kexec: export free_huge_page to VMCOREINFO · 8f1d26d0
    Atsushi Kumagai authored
    PG_head_mask was added into VMCOREINFO to filter huge pages in b3acc56b
    
    
    ("kexec: save PG_head_mask in VMCOREINFO"), but makedumpfile still need
    another symbol to filter *hugetlbfs* pages.
    
    If a user hope to filter user pages, makedumpfile tries to exclude them by
    checking the condition whether the page is anonymous, but hugetlbfs pages
    aren't anonymous while they also be user pages.
    
    We know it's possible to detect them in the same way as PageHuge(),
    so we need the start address of free_huge_page():
    
        int PageHuge(struct page *page)
        {
                if (!PageCompound(page))
                        return 0;
    
                page = compound_head(page);
                return get_compound_page_dtor(page) == free_huge_page;
        }
    
    For that reason, this patch changes free_huge_page() into public
    to export it to VMCOREINFO.
    Signed-off-by: default avatarAtsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
    Acked-by: default avatarBaoquan He <bhe@redhat.com>
    Cc: Vivek Goyal <vgoyal@redhat.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    8f1d26d0
hugetlb.h 12.7 KB