diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 162 |
1 files changed, 121 insertions, 41 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fd42321c02f0..96ca65636e40 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1627,16 +1627,100 @@ static unsigned long __init deferred_init_pages(struct zone *zone, return (nr_pages); } +/* + * This function is meant to pre-load the iterator for the zone init. + * Specifically it walks through the ranges until we are caught up to the + * first_init_pfn value and exits there. If we never encounter the value we + * return false indicating there are no valid ranges left. + */ +static bool __init +deferred_init_mem_pfn_range_in_zone(u64 *i, struct zone *zone, + unsigned long *spfn, unsigned long *epfn, + unsigned long first_init_pfn) +{ + u64 j; + + /* + * Start out by walking through the ranges in this zone that have + * already been initialized. We don't need to do anything with them + * so we just need to flush them out of the system. + */ + for_each_free_mem_pfn_range_in_zone(j, zone, spfn, epfn) { + if (*epfn <= first_init_pfn) + continue; + if (*spfn < first_init_pfn) + *spfn = first_init_pfn; + *i = j; + return true; + } + + return false; +} + +/* + * Initialize and free pages. We do it in two loops: first we initialize + * struct page, then free to buddy allocator, because while we are + * freeing pages we can access pages that are ahead (computing buddy + * page in __free_one_page()). + * + * In order to try and keep some memory in the cache we have the loop + * broken along max page order boundaries. This way we will not cause + * any issues with the buddy page computation. + */ +static unsigned long __init +deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn, + unsigned long *end_pfn) +{ + unsigned long mo_pfn = ALIGN(*start_pfn + 1, MAX_ORDER_NR_PAGES); + unsigned long spfn = *start_pfn, epfn = *end_pfn; + unsigned long nr_pages = 0; + u64 j = *i; + + /* First we loop through and initialize the page values */ + for_each_free_mem_pfn_range_in_zone_from(j, zone, start_pfn, end_pfn) { + unsigned long t; + + if (mo_pfn <= *start_pfn) + break; + + t = min(mo_pfn, *end_pfn); + nr_pages += deferred_init_pages(zone, *start_pfn, t); + + if (mo_pfn < *end_pfn) { + *start_pfn = mo_pfn; + break; + } + } + + /* Reset values and now loop through freeing pages as needed */ + swap(j, *i); + + for_each_free_mem_pfn_range_in_zone_from(j, zone, &spfn, &epfn) { + unsigned long t; + + if (mo_pfn <= spfn) + break; + + t = min(mo_pfn, epfn); + deferred_free_pages(spfn, t); + + if (mo_pfn <= epfn) + break; + } + + return nr_pages; +} + /* Initialise remaining memory on a node */ static int __init deferred_init_memmap(void *data) { pg_data_t *pgdat = data; + const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id); + unsigned long spfn = 0, epfn = 0, nr_pages = 0; + unsigned long first_init_pfn, flags; unsigned long start = jiffies; - unsigned long nr_pages = 0; - unsigned long spfn, epfn, first_init_pfn, flags; - int zid; struct zone *zone; - const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id); + int zid; u64 i; /* Bind memory initialisation thread to a local node if possible */ @@ -1662,22 +1746,20 @@ static int __init deferred_init_memmap(void *data) if (first_init_pfn < zone_end_pfn(zone)) break; } - first_init_pfn = max(zone->zone_start_pfn, first_init_pfn); + + /* If the zone is empty somebody else may have cleared out the zone */ + if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, + first_init_pfn)) + goto zone_empty; /* - * Initialize and free pages. We do it in two loops: first we initialize - * struct page, than free to buddy allocator, because while we are - * freeing pages we can access pages that are ahead (computing buddy - * page in __free_one_page()). + * Initialize and free pages in MAX_ORDER sized increments so + * that we can avoid introducing any issues with the buddy + * allocator. */ - for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) { - spfn = max_t(unsigned long, first_init_pfn, spfn); - nr_pages += deferred_init_pages(zone, spfn, epfn); - } - for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) { - spfn = max_t(unsigned long, first_init_pfn, spfn); - deferred_free_pages(spfn, epfn); - } + while (spfn < epfn) + nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn); +zone_empty: pgdat_resize_unlock(pgdat, &flags); /* Sanity check that the next zone really is unpopulated */ @@ -1710,9 +1792,9 @@ deferred_grow_zone(struct zone *zone, unsigned int order) { unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION); pg_data_t *pgdat = zone->zone_pgdat; - unsigned long nr_pages = 0; - unsigned long first_init_pfn, spfn, epfn, t, flags; unsigned long first_deferred_pfn = pgdat->first_deferred_pfn; + unsigned long spfn, epfn, flags; + unsigned long nr_pages = 0; u64 i; /* Only the last zone may have deferred pages */ @@ -1741,37 +1823,35 @@ deferred_grow_zone(struct zone *zone, unsigned int order) return true; } - first_init_pfn = max(zone->zone_start_pfn, first_deferred_pfn); - - if (first_init_pfn >= pgdat_end_pfn(pgdat)) { + /* If the zone is empty somebody else may have cleared out the zone */ + if (!deferred_init_mem_pfn_range_in_zone(&i, zone, &spfn, &epfn, + first_deferred_pfn)) { + pgdat->first_deferred_pfn = ULONG_MAX; pgdat_resize_unlock(pgdat, &flags); - return false; + return true; } - for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) { - spfn = max_t(unsigned long, first_init_pfn, spfn); + /* + * Initialize and free pages in MAX_ORDER sized increments so + * that we can avoid introducing any issues with the buddy + * allocator. + */ + while (spfn < epfn) { + /* update our first deferred PFN for this section */ + first_deferred_pfn = spfn; + + nr_pages += deferred_init_maxorder(&i, zone, &spfn, &epfn); - while (spfn < epfn && nr_pages < nr_pages_needed) { - t = ALIGN(spfn + PAGES_PER_SECTION, PAGES_PER_SECTION); - first_deferred_pfn = min(t, epfn); - nr_pages += deferred_init_pages(zone, spfn, - first_deferred_pfn); - spfn = first_deferred_pfn; - } + /* We should only stop along section boundaries */ + if ((first_deferred_pfn ^ spfn) < PAGES_PER_SECTION) + continue; + /* If our quota has been met we can stop here */ if (nr_pages >= nr_pages_needed) break; } - for_each_free_mem_pfn_range_in_zone(i, zone, &spfn, &epfn) { - spfn = max_t(unsigned long, first_init_pfn, spfn); - epfn = min_t(unsigned long, first_deferred_pfn, epfn); - deferred_free_pages(spfn, epfn); - - if (first_deferred_pfn == epfn) - break; - } - pgdat->first_deferred_pfn = first_deferred_pfn; + pgdat->first_deferred_pfn = spfn; pgdat_resize_unlock(pgdat, &flags); return nr_pages > 0; |