The patch titled hugetlb: support larger than MAX_ORDER has been removed from the -mm tree. Its filename was hugetlb-support-larger-than-max_order.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: hugetlb: support larger than MAX_ORDER From: Nick Piggin <npiggin@xxxxxxx> This is needed on x86-64 to handle GB pages in hugetlbfs, because it is not practical to enlarge MAX_ORDER to 1GB. Instead the 1GB pages are only allocated at boot using the bootmem allocator using the hugepages=... option. These 1G bootmem pages are never freed. In theory it would be possible to implement that with some complications, but since it would be a one-way street (>= MAX_ORDER pages cannot be allocated later) I decided not to currently. The >= MAX_ORDER code is not ifdef'ed per architecture. It is not very big and the ifdef uglyness seemed not be worth it. Known problems: /proc/meminfo and "free" do not display the memory allocated for gb pages in "Total". This is a little confusing for the user. Acked-by: Andrew Hastings <abh@xxxxxxxx> Signed-off-by: Andi Kleen <ak@xxxxxxx> Signed-off-by: Nick Piggin <npiggin@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 81 insertions(+), 2 deletions(-) diff -puN mm/hugetlb.c~hugetlb-support-larger-than-max_order mm/hugetlb.c --- a/mm/hugetlb.c~hugetlb-support-larger-than-max_order +++ a/mm/hugetlb.c @@ -14,6 +14,7 @@ #include <linux/mempolicy.h> #include <linux/cpuset.h> #include <linux/mutex.h> +#include <linux/bootmem.h> #include <linux/sysfs.h> #include <asm/page.h> @@ -489,7 +490,7 @@ static void free_huge_page(struct page * INIT_LIST_HEAD(&page->lru); spin_lock(&hugetlb_lock); - if (h->surplus_huge_pages_node[nid]) { + if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) { update_and_free_page(h, page); h->surplus_huge_pages--; h->surplus_huge_pages_node[nid]--; @@ -550,6 +551,9 @@ static struct page *alloc_fresh_huge_pag { struct page *page; + if (h->order >= MAX_ORDER) + return NULL; + page = alloc_pages_node(nid, htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE| __GFP_REPEAT|__GFP_NOWARN, @@ -616,6 +620,9 @@ static struct page *alloc_buddy_huge_pag struct page *page; unsigned int nid; + if (h->order >= MAX_ORDER) + return NULL; + /* * Assume we will successfully allocate the surplus page to * prevent racing processes from causing the surplus to exceed @@ -792,6 +799,10 @@ static void return_unused_surplus_pages( /* Uncommit the reservation */ h->resv_huge_pages -= unused_resv_pages; + /* Cannot return gigantic pages currently */ + if (h->order >= MAX_ORDER) + return; + nr_pages = min(unused_resv_pages, h->surplus_huge_pages); while (remaining_iterations-- && nr_pages) { @@ -913,6 +924,63 @@ static struct page *alloc_huge_page(stru return page; } +static __initdata LIST_HEAD(huge_boot_pages); + +struct huge_bootmem_page { + struct list_head list; + struct hstate *hstate; +}; + +static int __init alloc_bootmem_huge_page(struct hstate *h) +{ + struct huge_bootmem_page *m; + int nr_nodes = nodes_weight(node_online_map); + + while (nr_nodes) { + void *addr; + + addr = __alloc_bootmem_node_nopanic( + NODE_DATA(h->hugetlb_next_nid), + huge_page_size(h), huge_page_size(h), 0); + + if (addr) { + /* + * Use the beginning of the huge page to store the + * huge_bootmem_page struct (until gather_bootmem + * puts them into the mem_map). + */ + m = addr; + if (m) + goto found; + } + hstate_next_node(h); + nr_nodes--; + } + return 0; + +found: + BUG_ON((unsigned long)virt_to_phys(m) & (huge_page_size(h) - 1)); + /* Put them into a private list first because mem_map is not up yet */ + list_add(&m->list, &huge_boot_pages); + m->hstate = h; + return 1; +} + +/* Put bootmem huge pages into the standard lists after mem_map is up */ +static void __init gather_bootmem_prealloc(void) +{ + struct huge_bootmem_page *m; + + list_for_each_entry(m, &huge_boot_pages, list) { + struct page *page = virt_to_page(m); + struct hstate *h = m->hstate; + __ClearPageReserved(page); + WARN_ON(page_count(page) != 1); + prep_compound_page(page, h->order); + prep_new_huge_page(h, page, page_to_nid(page)); + } +} + static void __init hugetlb_init_one_hstate(struct hstate *h) { unsigned long i; @@ -923,7 +991,10 @@ static void __init hugetlb_init_one_hsta h->hugetlb_next_nid = first_node(node_online_map); for (i = 0; i < h->max_huge_pages; ++i) { - if (!alloc_fresh_huge_page(h)) + if (h->order >= MAX_ORDER) { + if (!alloc_bootmem_huge_page(h)) + break; + } else if (!alloc_fresh_huge_page(h)) break; } h->max_huge_pages = h->free_huge_pages = h->nr_huge_pages = i; @@ -956,6 +1027,9 @@ static void try_to_free_low(struct hstat { int i; + if (h->order >= MAX_ORDER) + return; + for (i = 0; i < MAX_NUMNODES; ++i) { struct page *page, *next; struct list_head *freel = &h->hugepage_freelists[i]; @@ -982,6 +1056,9 @@ static unsigned long set_max_huge_pages( { unsigned long min_count, ret; + if (h->order >= MAX_ORDER) + return h->max_huge_pages; + /* * Increase the pool size * First take pages out of surplus state. Then make up the @@ -1210,6 +1287,8 @@ static int __init hugetlb_init(void) hugetlb_init_hstates(); + gather_bootmem_prealloc(); + report_hugepages(); hugetlb_sysfs_init(); _ Patches currently in -mm which might be from npiggin@xxxxxxx are origin.patch linux-next.patch mmu-notifiers-add-list_del_init_rcu.patch mmu-notifiers-add-mm_take_all_locks-operation.patch mmu-notifier-core.patch x86-implement-pte_special.patch x86-implement-pte_special-fix.patch mm-introduce-get_user_pages_fast.patch mm-introduce-get_user_pages_fast-fix.patch mm-introduce-get_user_pages_fast-checkpatch-fixes.patch x86-lockless-get_user_pages_fast.patch x86-lockless-get_user_pages_fast-checkpatch-fixes.patch x86-lockless-get_user_pages_fast-fix.patch x86-lockless-get_user_pages_fast-fix-2.patch x86-lockless-get_user_pages_fast-fix-2-fix-fix.patch x86-lockless-get_user_pages_fast-fix-warning.patch dio-use-get_user_pages_fast.patch splice-use-get_user_pages_fast.patch x86-support-1gb-hugepages-with-get_user_pages_lockless.patch mm-readahead-scan-lockless.patch radix-tree-add-gang_lookup_slot-gang_lookup_slot_tag.patch mm-speculative-page-references.patch mm-speculative-page-references-fix.patch mm-speculative-page-references-fix-add_to_page_cache.patch mm-speculative-page-references-fix-add_to_page_cache-fix.patch mm-lockless-pagecache.patch mm-spinlock-tree_lock.patch powerpc-implement-pte_special.patch powerpc-implement-pte_special-update.patch powerpc-lockless-get_user_pages.patch vmscan-move-isolate_lru_page-to-vmscanc.patch vmscan-move-isolate_lru_page-to-vmscanc-fix.patch vmscan-split-lru-lists-into-anon-file-sets-splitlru-bdi_cap_swap_backed.patch mlock-mlocked-pages-are-unevictable.patch mlock-mlocked-pages-are-unevictable-fix.patch mlock-mlocked-pages-are-unevictable-fix-fix.patch mlock-mlocked-pages-are-unevictable-fix-3.patch mlock-mlocked-pages-are-unevictable-fix-fix-munlock-page-table-walk-now-requires-mm.patch mmap-handle-mlocked-pages-during-map-remap-unmap.patch mmap-handle-mlocked-pages-during-map-remap-unmap-cleanup.patch fix-double-unlock_page-in-2626-rc5-mm3-kernel-bug-at-mm-filemapc-575.patch vmstat-mlocked-pages-statistics.patch vmstat-mlocked-pages-statistics-fix-incorrect-mlocked-field-of-proc-meminfo.patch reiser4.patch likeliness-accounting-change-and-cleanup.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html