From a0368d4e48fc9ad65a66f6819a801f3f542b4f0f Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Tue, 21 Jan 2014 15:48:49 -0800 Subject: mm: hugetlb: use get_page_foll() in follow_hugetlb_page() get_page_foll() is more optimal and is always safe to use under the PT lock. More so for hugetlbfs as there's no risk of race conditions with split_huge_page regardless of the PT lock. Signed-off-by: Andrea Arcangeli Tested-by: Khalid Aziz Cc: Pravin Shelar Cc: Greg Kroah-Hartman Cc: Ben Hutchings Cc: Christoph Lameter Cc: Johannes Weiner Cc: Mel Gorman Cc: Rik van Riel Cc: Andi Kleen Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index dee6cf4e6d34..7596e104bffa 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3079,7 +3079,7 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, same_page: if (pages) { pages[i] = mem_map_offset(page, pfn_offset); - get_page(pages[i]); + get_page_foll(pages[i]); } if (vmas) -- cgit v1.2.3 From 758f66a29ccc6383353fd395aa04be15e8dea445 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Tue, 21 Jan 2014 15:48:57 -0800 Subject: mm/hugetlb.c: simplify PageHeadHuge() and PageHuge() Signed-off-by: Andrea Arcangeli Cc: Khalid Aziz Cc: Pravin Shelar Cc: Greg Kroah-Hartman Cc: Ben Hutchings Cc: Christoph Lameter Cc: Johannes Weiner Cc: Mel Gorman Cc: Rik van Riel Cc: Andi Kleen Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 7596e104bffa..1d9125360bf5 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -690,15 +690,11 @@ static void prep_compound_gigantic_page(struct page *page, unsigned long order) */ int PageHuge(struct page *page) { - compound_page_dtor *dtor; - if (!PageCompound(page)) return 0; page = compound_head(page); - dtor = get_compound_page_dtor(page); - - return dtor == free_huge_page; + return get_compound_page_dtor(page) == free_huge_page; } EXPORT_SYMBOL_GPL(PageHuge); @@ -708,14 +704,10 @@ EXPORT_SYMBOL_GPL(PageHuge); */ int PageHeadHuge(struct page *page_head) { - compound_page_dtor *dtor; - if (!PageHead(page_head)) return 0; - dtor = get_compound_page_dtor(page_head); - - return dtor == free_huge_page; + return get_compound_page_dtor(page_head) == free_huge_page; } EXPORT_SYMBOL_GPL(PageHeadHuge); -- cgit v1.2.3 From 9b7ac260188ddacffdcaadd6a61e4a502238a63f Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Tue, 21 Jan 2014 15:49:01 -0800 Subject: mm/hugetlb.c: defer PageHeadHuge() symbol export No actual need of it. So keep it internal. Signed-off-by: Andrea Arcangeli Cc: Khalid Aziz Cc: Pravin Shelar Cc: Greg Kroah-Hartman Cc: Ben Hutchings Cc: Christoph Lameter Cc: Johannes Weiner Cc: Mel Gorman Cc: Rik van Riel Cc: Andi Kleen Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 1 - 1 file changed, 1 deletion(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 1d9125360bf5..f730b7a37590 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -709,7 +709,6 @@ int PageHeadHuge(struct page *page_head) return get_compound_page_dtor(page_head) == free_huge_page; } -EXPORT_SYMBOL_GPL(PageHeadHuge); pgoff_t __basepage_index(struct page *page) { -- cgit v1.2.3 From e8569dd299dbc7bac878325c0bdc7aa449eae479 Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Tue, 21 Jan 2014 15:49:09 -0800 Subject: mm/hugetlb.c: call MMU notifiers when copying a hugetlb page range When copy_hugetlb_page_range() is called to copy a range of hugetlb mappings, the secondary MMUs are not notified if there is a protection downgrade, which breaks COW semantics in KVM. This patch adds the necessary MMU notifier calls. Signed-off-by: Andreas Sandberg Acked-by: Steve Capper Acked-by: Marc Zyngier Cc: Mel Gorman Cc: Rik van Riel Cc: Hugh Dickins Cc: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f730b7a37590..1697ff0cc53a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2346,17 +2346,27 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, int cow; struct hstate *h = hstate_vma(vma); unsigned long sz = huge_page_size(h); + unsigned long mmun_start; /* For mmu_notifiers */ + unsigned long mmun_end; /* For mmu_notifiers */ + int ret = 0; cow = (vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; + mmun_start = vma->vm_start; + mmun_end = vma->vm_end; + if (cow) + mmu_notifier_invalidate_range_start(src, mmun_start, mmun_end); + for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { spinlock_t *src_ptl, *dst_ptl; src_pte = huge_pte_offset(src, addr); if (!src_pte) continue; dst_pte = huge_pte_alloc(dst, addr, sz); - if (!dst_pte) - goto nomem; + if (!dst_pte) { + ret = -ENOMEM; + break; + } /* If the pagetables are shared don't copy or take references */ if (dst_pte == src_pte) @@ -2377,10 +2387,11 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, spin_unlock(src_ptl); spin_unlock(dst_ptl); } - return 0; -nomem: - return -ENOMEM; + if (cow) + mmu_notifier_invalidate_range_end(src, mmun_start, mmun_end); + + return ret; } static int is_hugetlb_entry_migration(pte_t pte) -- cgit v1.2.3 From 8b89a1169437541a2a9b62c8f7b1a5c0ceb0fbde Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Tue, 21 Jan 2014 15:50:36 -0800 Subject: mm/hugetlb.c: use memblock apis for early memory allocations Switch to memblock interfaces for early memory allocator instead of bootmem allocator. No functional change in beahvior than what it is in current code from bootmem users points of view. Archs already converted to NO_BOOTMEM now directly use memblock interfaces instead of bootmem wrappers build on top of memblock. And the archs which still uses bootmem, these new apis just fallback to exiting bootmem APIs. Signed-off-by: Grygorii Strashko Signed-off-by: Santosh Shilimkar Cc: "Rafael J. Wysocki" Cc: Arnd Bergmann Cc: Christoph Lameter Cc: Greg Kroah-Hartman Cc: H. Peter Anvin Cc: Johannes Weiner Cc: KAMEZAWA Hiroyuki Cc: Konrad Rzeszutek Wilk Cc: Michal Hocko Cc: Paul Walmsley Cc: Pavel Machek Cc: Russell King Cc: Tejun Heo Cc: Tony Lindgren Cc: Yinghai Lu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 1697ff0cc53a..04306b9de90d 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1271,9 +1271,9 @@ int __weak alloc_bootmem_huge_page(struct hstate *h) for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { void *addr; - addr = __alloc_bootmem_node_nopanic(NODE_DATA(node), - huge_page_size(h), huge_page_size(h), 0); - + addr = memblock_virt_alloc_try_nid_nopanic( + huge_page_size(h), huge_page_size(h), + 0, BOOTMEM_ALLOC_ACCESSIBLE, node); if (addr) { /* * Use the beginning of the huge page to store the @@ -1313,8 +1313,8 @@ static void __init gather_bootmem_prealloc(void) #ifdef CONFIG_HIGHMEM page = pfn_to_page(m->phys >> PAGE_SHIFT); - free_bootmem_late((unsigned long)m, - sizeof(struct huge_bootmem_page)); + memblock_free_late(__pa(m), + sizeof(struct huge_bootmem_page)); #else page = virt_to_page(m); #endif -- cgit v1.2.3 From 309381feaee564281c3d9e90fbca8963bb7428ad Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Thu, 23 Jan 2014 15:52:54 -0800 Subject: mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE Most of the VM_BUG_ON assertions are performed on a page. Usually, when one of these assertions fails we'll get a BUG_ON with a call stack and the registers. I've recently noticed based on the requests to add a small piece of code that dumps the page to various VM_BUG_ON sites that the page dump is quite useful to people debugging issues in mm. This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what VM_BUG_ON() does, also dumps the page before executing the actual BUG_ON. [akpm@linux-foundation.org: fix up includes] Signed-off-by: Sasha Levin Cc: "Kirill A. Shutemov" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 04306b9de90d..c01cb9fedb18 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -584,7 +584,7 @@ static void update_and_free_page(struct hstate *h, struct page *page) 1 << PG_active | 1 << PG_reserved | 1 << PG_private | 1 << PG_writeback); } - VM_BUG_ON(hugetlb_cgroup_from_page(page)); + VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page); set_compound_page_dtor(page, NULL); set_page_refcounted(page); arch_release_hugepage(page); @@ -1089,7 +1089,7 @@ retry: * no users -- drop the buddy allocator's reference. */ put_page_testzero(page); - VM_BUG_ON(page_count(page)); + VM_BUG_ON_PAGE(page_count(page), page); enqueue_huge_page(h, page); } free: @@ -3503,7 +3503,7 @@ int dequeue_hwpoisoned_huge_page(struct page *hpage) bool isolate_huge_page(struct page *page, struct list_head *list) { - VM_BUG_ON(!PageHead(page)); + VM_BUG_ON_PAGE(!PageHead(page), page); if (!get_page_unless_zero(page)) return false; spin_lock(&hugetlb_lock); @@ -3514,7 +3514,7 @@ bool isolate_huge_page(struct page *page, struct list_head *list) void putback_active_hugepage(struct page *page) { - VM_BUG_ON(!PageHead(page)); + VM_BUG_ON_PAGE(!PageHead(page), page); spin_lock(&hugetlb_lock); list_move_tail(&page->lru, &(page_hstate(page))->hugepage_activelist); spin_unlock(&hugetlb_lock); @@ -3523,7 +3523,7 @@ void putback_active_hugepage(struct page *page) bool is_hugepage_active(struct page *page) { - VM_BUG_ON(!PageHuge(page)); + VM_BUG_ON_PAGE(!PageHuge(page), page); /* * This function can be called for a tail page because the caller, * scan_movable_pages, scans through a given pfn-range which typically -- cgit v1.2.3