From: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Subject: hugetlb: add lockdep_assert_held() calls for hugetlb_lock After making hugetlb lock irq safe and separating some functionality done under the lock, add some lockdep_assert_held to help verify locking. Link: https://lkml.kernel.org/r/20210409205254.242291-9-mike.kravetz@xxxxxxxxxx Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Cc: "Aneesh Kumar K . V" <aneesh.kumar@xxxxxxxxxxxxx> Cc: Barry Song <song.bao.hua@xxxxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Hillf Danton <hdanton@xxxxxxxx> Cc: HORIGUCHI NAOYA <naoya.horiguchi@xxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Mina Almasry <almasrymina@xxxxxxxxxx> Cc: Peter Xu <peterx@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Roman Gushchin <guro@xxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: Waiman Long <longman@xxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/mm/hugetlb.c~hugetlb-add-lockdep_assert_held-calls-for-hugetlb_lock +++ a/mm/hugetlb.c @@ -1069,6 +1069,8 @@ static bool vma_has_reserves(struct vm_a static void enqueue_huge_page(struct hstate *h, struct page *page) { int nid = page_to_nid(page); + + lockdep_assert_held(&hugetlb_lock); list_move(&page->lru, &h->hugepage_freelists[nid]); h->free_huge_pages++; h->free_huge_pages_node[nid]++; @@ -1080,6 +1082,7 @@ static struct page *dequeue_huge_page_no struct page *page; bool nocma = !!(current->flags & PF_MEMALLOC_NOCMA); + lockdep_assert_held(&hugetlb_lock); list_for_each_entry(page, &h->hugepage_freelists[nid], lru) { if (nocma && is_migrate_cma_page(page)) continue; @@ -1351,6 +1354,7 @@ static void remove_hugetlb_page(struct h VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page); VM_BUG_ON_PAGE(hugetlb_cgroup_from_page_rsvd(page), page); + lockdep_assert_held(&hugetlb_lock); if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) return; @@ -1701,6 +1705,7 @@ static struct page *remove_pool_huge_pag int nr_nodes, node; struct page *page = NULL; + lockdep_assert_held(&hugetlb_lock); for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { /* * If we're returning unused surplus pages, only examine @@ -1950,6 +1955,7 @@ static int gather_surplus_pages(struct h long needed, allocated; bool alloc_ok = true; + lockdep_assert_held(&hugetlb_lock); needed = (h->resv_huge_pages + delta) - h->free_huge_pages; if (needed <= 0) { h->resv_huge_pages += delta; @@ -2043,6 +2049,7 @@ static void return_unused_surplus_pages( struct page *page; LIST_HEAD(page_list); + lockdep_assert_held(&hugetlb_lock); /* Uncommit the reservation */ h->resv_huge_pages -= unused_resv_pages; @@ -2530,6 +2537,7 @@ static void try_to_free_low(struct hstat int i; LIST_HEAD(page_list); + lockdep_assert_held(&hugetlb_lock); if (hstate_is_gigantic(h)) return; @@ -2571,6 +2579,7 @@ static int adjust_pool_surplus(struct hs { int nr_nodes, node; + lockdep_assert_held(&hugetlb_lock); VM_BUG_ON(delta != -1 && delta != 1); if (delta < 0) { _
