PATCH/RFC 2/4 hugetlb: numafy several functions Against: 2.6.31-rc3-mmotm-090716-1432 atop the previously posted alloc_bootmem_hugepages fix. [http://marc.info/?l=linux-mm&m=124775468226290&w=4] Based on a patch by Nishanth Aravamudan <nacc@xxxxxxxxxx>, circa april2008. Factor out functions to dequeue and free huge pages and/or adjust surplus huge page count for a specific node in support of subsequent patch to alloc or free huge pages on a specified node. Signed-off-by: Lee Schermerhorn <lee.schermerhorn@xxxxxx> --- mm/hugetlb.c | 126 +++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 72 insertions(+), 54 deletions(-) Index: linux-2.6.31-rc3-mmotm-090716-1432/mm/hugetlb.c =================================================================== --- linux-2.6.31-rc3-mmotm-090716-1432.orig/mm/hugetlb.c 2009-07-23 11:10:29.000000000 -0400 +++ linux-2.6.31-rc3-mmotm-090716-1432/mm/hugetlb.c 2009-07-27 15:26:39.000000000 -0400 @@ -456,6 +456,17 @@ static void enqueue_huge_page(struct hst h->free_huge_pages_node[nid]++; } +static struct page *hstate_dequeue_huge_page_node(struct hstate *h, int nid) +{ + struct page *page; + + page = list_entry(h->hugepage_freelists[nid].next, struct page, lru); + list_del(&page->lru); + h->free_huge_pages--; + h->free_huge_pages_node[nid]--; + return page; +} + static struct page *dequeue_huge_page_vma(struct hstate *h, struct vm_area_struct *vma, unsigned long address, int avoid_reserve) @@ -487,11 +498,7 @@ static struct page *dequeue_huge_page_vm nid = zone_to_nid(zone); if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask) && !list_empty(&h->hugepage_freelists[nid])) { - page = list_entry(h->hugepage_freelists[nid].next, - struct page, lru); - list_del(&page->lru); - h->free_huge_pages--; - h->free_huge_pages_node[nid]--; + page = hstate_dequeue_huge_page_node(h, nid); if (!avoid_reserve) decrement_hugepage_resv_vma(h, vma); @@ -599,12 +606,12 @@ int PageHuge(struct page *page) return dtor == free_huge_page; } -static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) +static int alloc_fresh_huge_page_node(struct hstate *h, int nid) { struct page *page; if (h->order >= MAX_ORDER) - return NULL; + return 0; page = alloc_pages_exact_node(nid, htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE| @@ -613,12 +620,12 @@ static struct page *alloc_fresh_huge_pag if (page) { if (arch_prepare_hugepage(page)) { __free_pages(page, huge_page_order(h)); - return NULL; + return 0; } prep_new_huge_page(h, page, nid); } - return page; + return 1; } /* @@ -658,7 +665,6 @@ static int hstate_next_node_to_alloc(str static int alloc_fresh_huge_page(struct hstate *h) { - struct page *page; int start_nid; int next_nid; int ret = 0; @@ -667,11 +673,9 @@ static int alloc_fresh_huge_page(struct next_nid = start_nid; do { - page = alloc_fresh_huge_page_node(h, next_nid); - if (page) { - ret = 1; + ret = alloc_fresh_huge_page_node(h, next_nid); + if (ret) break; - } next_nid = hstate_next_node_to_alloc(h); } while (next_nid != start_nid); @@ -699,6 +703,23 @@ static int hstate_next_node_to_free(stru return nid; } +static int hstate_free_huge_page_node(struct hstate *h, bool acct_surplus, + int nid) +{ + struct page *page; + + if (list_empty(&h->hugepage_freelists[nid])) + return 0; + + page = hstate_dequeue_huge_page_node(h, nid); + if (acct_surplus) { + h->surplus_huge_pages--; + h->surplus_huge_pages_node[nid]--; + } + update_and_free_page(h, page); + return 1; +} + /* * Free huge page from pool from next node to free. * Attempt to keep persistent huge pages more or less @@ -719,21 +740,11 @@ static int free_pool_huge_page(struct hs * If we're returning unused surplus pages, only examine * nodes with surplus pages. */ - if ((!acct_surplus || h->surplus_huge_pages_node[next_nid]) && - !list_empty(&h->hugepage_freelists[next_nid])) { - struct page *page = - list_entry(h->hugepage_freelists[next_nid].next, - struct page, lru); - list_del(&page->lru); - h->free_huge_pages--; - h->free_huge_pages_node[next_nid]--; - if (acct_surplus) { - h->surplus_huge_pages--; - h->surplus_huge_pages_node[next_nid]--; - } - update_and_free_page(h, page); - ret = 1; - break; + if ((!acct_surplus || h->surplus_huge_pages_node[next_nid])) { + ret = hstate_free_huge_page_node(h, acct_surplus, + next_nid); + if (ret) + break; } next_nid = hstate_next_node_to_free(h); } while (next_nid != start_nid); @@ -1173,6 +1184,31 @@ static inline void try_to_free_low(struc #endif /* + * Increment or decrement surplus_huge_pages for a specified node, + * if conditions permit. Note that decrementing the surplus huge + * page count effective promotes a page to persistent, while + * incrementing the surplus count demotes a page to surplus. + */ +static int adjust_pool_surplus_node(struct hstate *h, int delta, int nid) +{ + int ret = 0; + + /* + * To shrink on this node, there must be a surplus page. + * Surplus cannot exceed the total number of pages. + */ + if ((delta < 0 && h->surplus_huge_pages_node[nid]) || + (delta > 0 && h->surplus_huge_pages_node[nid] < + h->nr_huge_pages_node[nid])) { + + h->surplus_huge_pages += delta; + h->surplus_huge_pages_node[nid] += delta; + ret = 1; + } + return ret; +} + +/* * Increment or decrement surplus_huge_pages. Keep node-specific counters * balanced by operating on them in a round-robin fashion. * Returns 1 if an adjustment was made. @@ -1191,31 +1227,13 @@ static int adjust_pool_surplus(struct hs next_nid = start_nid; do { - int nid = next_nid; - if (delta < 0) { - /* - * To shrink on this node, there must be a surplus page - */ - if (!h->surplus_huge_pages_node[nid]) { - next_nid = hstate_next_node_to_alloc(h); - continue; - } - } - if (delta > 0) { - /* - * Surplus cannot exceed the total number of pages - */ - if (h->surplus_huge_pages_node[nid] >= - h->nr_huge_pages_node[nid]) { - next_nid = hstate_next_node_to_free(h); - continue; - } - } - - h->surplus_huge_pages += delta; - h->surplus_huge_pages_node[nid] += delta; - ret = 1; - break; + ret = adjust_pool_surplus_node(h, delta, next_nid); + if (ret) + break; + if (delta < 0) + next_nid = hstate_next_node_to_alloc(h); + else + next_nid = hstate_next_node_to_free(h); } while (next_nid != start_nid); return ret; -- To unsubscribe from this list: send the line "unsubscribe linux-numa" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
