From: Michal Hocko <mhocko@xxxxxxxx> Subject: hugetlb: add support for preferred node to alloc_huge_page_nodemask alloc_huge_page_nodemask tries to allocate from any numa node in the allowed node mask starting from lower numa nodes. This might lead to filling up those low NUMA nodes while others are not used. We can reduce this risk by introducing a concept of the preferred node similar to what we have in the regular page allocator. We will start allocating from the preferred nid and then iterate over all allowed nodes in the zonelist order until we try them all. This is mimicing the page allocator logic except it operates on per-node mempools. dequeue_huge_page_vma already does this so distill the zonelist logic into a more generic dequeue_huge_page_nodemask and use it in alloc_huge_page_nodemask. This will allow us to use proper per numa distance fallback also for alloc_huge_page_node which can use alloc_huge_page_nodemask now and we can get rid of alloc_huge_page_node helper which doesn't have any user anymore. Link: http://lkml.kernel.org/r/20170622193034.28972-3-mhocko@xxxxxxxxxx Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Tested-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/hugetlb.h | 5 +- include/linux/migrate.h | 2 mm/hugetlb.c | 88 +++++++++++++++++++------------------- 3 files changed, 48 insertions(+), 47 deletions(-) diff -puN include/linux/hugetlb.h~hugetlb-add-support-for-preferred-node-to-alloc_huge_page_nodemask include/linux/hugetlb.h --- a/include/linux/hugetlb.h~hugetlb-add-support-for-preferred-node-to-alloc_huge_page_nodemask +++ a/include/linux/hugetlb.h @@ -349,7 +349,8 @@ struct page *alloc_huge_page(struct vm_a struct page *alloc_huge_page_node(struct hstate *h, int nid); struct page *alloc_huge_page_noerr(struct vm_area_struct *vma, unsigned long addr, int avoid_reserve); -struct page *alloc_huge_page_nodemask(struct hstate *h, nodemask_t *nmask); +struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, + nodemask_t *nmask); int huge_add_to_page_cache(struct page *page, struct address_space *mapping, pgoff_t idx); @@ -525,7 +526,7 @@ static inline void set_huge_swap_pte_at( struct hstate {}; #define alloc_huge_page(v, a, r) NULL #define alloc_huge_page_node(h, nid) NULL -#define alloc_huge_page_nodemask(h, nmask) NULL +#define alloc_huge_page_nodemask(h, preferred_nid, nmask) NULL #define alloc_huge_page_noerr(v, a, r) NULL #define alloc_bootmem_huge_page(h) NULL #define hstate_file(f) NULL diff -puN include/linux/migrate.h~hugetlb-add-support-for-preferred-node-to-alloc_huge_page_nodemask include/linux/migrate.h --- a/include/linux/migrate.h~hugetlb-add-support-for-preferred-node-to-alloc_huge_page_nodemask +++ a/include/linux/migrate.h @@ -38,7 +38,7 @@ static inline struct page *new_page_node if (PageHuge(page)) return alloc_huge_page_nodemask(page_hstate(compound_head(page)), - nodemask); + preferred_nid, nodemask); if (PageHighMem(page) || (zone_idx(page_zone(page)) == ZONE_MOVABLE)) gfp_mask |= __GFP_HIGHMEM; diff -puN mm/hugetlb.c~hugetlb-add-support-for-preferred-node-to-alloc_huge_page_nodemask mm/hugetlb.c --- a/mm/hugetlb.c~hugetlb-add-support-for-preferred-node-to-alloc_huge_page_nodemask +++ a/mm/hugetlb.c @@ -887,19 +887,39 @@ static struct page *dequeue_huge_page_no return page; } -static struct page *dequeue_huge_page_node(struct hstate *h, int nid) +static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t gfp_mask, int nid, + nodemask_t *nmask) { - struct page *page; - int node; + unsigned int cpuset_mems_cookie; + struct zonelist *zonelist; + struct zone *zone; + struct zoneref *z; + int node = -1; - if (nid != NUMA_NO_NODE) - return dequeue_huge_page_node_exact(h, nid); + zonelist = node_zonelist(nid, gfp_mask); + +retry_cpuset: + cpuset_mems_cookie = read_mems_allowed_begin(); + for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nmask) { + struct page *page; + + if (!cpuset_zone_allowed(zone, gfp_mask)) + continue; + /* + * no need to ask again on the same node. Pool is node rather than + * zone aware + */ + if (zone_to_nid(zone) == node) + continue; + node = zone_to_nid(zone); - for_each_online_node(node) { page = dequeue_huge_page_node_exact(h, node); if (page) return page; } + if (unlikely(read_mems_allowed_retry(cpuset_mems_cookie))) + goto retry_cpuset; + return NULL; } @@ -917,15 +937,11 @@ static struct page *dequeue_huge_page_vm unsigned long address, int avoid_reserve, long chg) { - struct page *page = NULL; + struct page *page; struct mempolicy *mpol; - nodemask_t *nodemask; gfp_t gfp_mask; + nodemask_t *nodemask; int nid; - struct zonelist *zonelist; - struct zone *zone; - struct zoneref *z; - unsigned int cpuset_mems_cookie; /* * A child process with MAP_PRIVATE mappings created by their parent @@ -940,32 +956,15 @@ static struct page *dequeue_huge_page_vm if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0) goto err; -retry_cpuset: - cpuset_mems_cookie = read_mems_allowed_begin(); gfp_mask = htlb_alloc_mask(h); nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask); - zonelist = node_zonelist(nid, gfp_mask); - - for_each_zone_zonelist_nodemask(zone, z, zonelist, - MAX_NR_ZONES - 1, nodemask) { - if (cpuset_zone_allowed(zone, gfp_mask)) { - page = dequeue_huge_page_node(h, zone_to_nid(zone)); - if (page) { - if (avoid_reserve) - break; - if (!vma_has_reserves(vma, chg)) - break; - - SetPagePrivate(page); - h->resv_huge_pages--; - break; - } - } + page = dequeue_huge_page_nodemask(h, gfp_mask, nid, nodemask); + if (page && !avoid_reserve && vma_has_reserves(vma, chg)) { + SetPagePrivate(page); + h->resv_huge_pages--; } mpol_cond_put(mpol); - if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie))) - goto retry_cpuset; return page; err: @@ -1633,7 +1632,7 @@ struct page *alloc_huge_page_node(struct spin_lock(&hugetlb_lock); if (h->free_huge_pages - h->resv_huge_pages > 0) - page = dequeue_huge_page_node(h, nid); + page = dequeue_huge_page_nodemask(h, gfp_mask, nid, NULL); spin_unlock(&hugetlb_lock); if (!page) @@ -1642,26 +1641,27 @@ struct page *alloc_huge_page_node(struct return page; } -struct page *alloc_huge_page_nodemask(struct hstate *h, nodemask_t *nmask) + +struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, + nodemask_t *nmask) { gfp_t gfp_mask = htlb_alloc_mask(h); - struct page *page = NULL; - int node; spin_lock(&hugetlb_lock); if (h->free_huge_pages - h->resv_huge_pages > 0) { - for_each_node_mask(node, *nmask) { - page = dequeue_huge_page_node_exact(h, node); - if (page) - break; + struct page *page; + + page = dequeue_huge_page_nodemask(h, gfp_mask, preferred_nid, nmask); + if (page) { + spin_unlock(&hugetlb_lock); + return page; } } spin_unlock(&hugetlb_lock); - if (page) - return page; /* No reservations, try to overcommit */ - return __alloc_buddy_huge_page(h, gfp_mask, NUMA_NO_NODE, nmask); + + return __alloc_buddy_huge_page(h, gfp_mask, preferred_nid, nmask); } /* _ -- 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
