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Because the race window is small. Signed-off-by: Muchun Song --- mm/hugetlb.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 72608008f8b4..db00ae375d2a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1763,10 +1763,11 @@ static int free_pool_huge_page(struct hstate *h, = nodemask_t *nodes_allowed, * nothing for in-use hugepages and non-hugepages. * This function returns values like below: * - * -EBUSY: failed to dissolved free hugepages or the hugepage is in-use - * (allocated or reserved.) - * 0: successfully dissolved free hugepages or the page is not a - * hugepage (considered as already dissolved) + * -EAGAIN: race with __free_huge_page() and can do a retry + * -EBUSY: failed to dissolved free hugepages or the hugepage is in-us= e + * (allocated or reserved.) + * 0: successfully dissolved free hugepages or the page is not a + * hugepage (considered as already dissolved) */ int dissolve_free_huge_page(struct page *page) { @@ -1815,8 +1816,10 @@ int dissolve_free_huge_page(struct page *page) * We should make sure that the page is already on the free list * when it is dissolved. */ - if (unlikely(!PageHugeFreed(head))) + if (unlikely(!PageHugeFreed(head))) { + rc =3D -EAGAIN; goto out; + } =20 /* * Move PageHWPoison flag from head page to the raw error page, @@ -1857,7 +1860,10 @@ int dissolve_free_huge_pages(unsigned long start_p= fn, unsigned long end_pfn) =20 for (pfn =3D start_pfn; pfn < end_pfn; pfn +=3D 1 << minimum_order) { page =3D pfn_to_page(pfn); +retry: rc =3D dissolve_free_huge_page(page); + if (rc =3D=3D -EAGAIN) + goto retry; if (rc) break; } --=20 2.11.0