unsigned long totalram_pages __read_mostly;
unsigned long totalreserve_pages __read_mostly;
unsigned long totalcma_pages __read_mostly;
-/*
- * When calculating the number of globally allowed dirty pages, there
- * is a certain number of per-zone reserves that should not be
- * considered dirtyable memory. This is the sum of those reserves
- * over all existing zones that contribute dirtyable memory.
- */
-unsigned long dirty_balance_reserve __read_mostly;
int percpu_pagelist_fraction;
gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
#endif
};
+/*
+ * Try to keep at least this much lowmem free. Do not allow normal
+ * allocations below this point, only high priority ones. Automatically
+ * tuned according to the amount of memory in the system.
+ */
int min_free_kbytes = 1024;
int user_min_free_kbytes = -1;
+/*
+ * Extra memory for the system to try freeing. Used to temporarily
+ * free memory, to make space for new workloads. Anyone can allocate
+ * down to the min watermarks controlled by min_free_kbytes above.
+ */
+int extra_free_kbytes = 0;
+
static unsigned long __meminitdata nr_kernel_pages;
static unsigned long __meminitdata nr_all_pages;
static unsigned long __meminitdata dma_reserve;
/* Returns true if the struct page for the pfn is uninitialised */
static inline bool __meminit early_page_uninitialised(unsigned long pfn)
{
- if (pfn >= NODE_DATA(early_pfn_to_nid(pfn))->first_deferred_pfn)
+ int nid = early_pfn_to_nid(pfn);
+
+ if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn)
return true;
return false;
spin_lock(&early_pfn_lock);
nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache);
if (nid < 0)
- nid = 0;
+ nid = first_online_node;
spin_unlock(&early_pfn_lock);
return nid;
static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
{
- return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <
+ return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <=
RECLAIM_DISTANCE;
}
#else /* CONFIG_NUMA */
sizeof(arch_zone_lowest_possible_pfn));
memset(arch_zone_highest_possible_pfn, 0,
sizeof(arch_zone_highest_possible_pfn));
- arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
- arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
- for (i = 1; i < MAX_NR_ZONES; i++) {
+
+ start_pfn = find_min_pfn_with_active_regions();
+
+ for (i = 0; i < MAX_NR_ZONES; i++) {
if (i == ZONE_MOVABLE)
continue;
- arch_zone_lowest_possible_pfn[i] =
- arch_zone_highest_possible_pfn[i-1];
- arch_zone_highest_possible_pfn[i] =
- max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
+
+ end_pfn = max(max_zone_pfn[i], start_pfn);
+ arch_zone_lowest_possible_pfn[i] = start_pfn;
+ arch_zone_highest_possible_pfn[i] = end_pfn;
+
+ start_pfn = end_pfn;
}
arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
if (max > zone->managed_pages)
max = zone->managed_pages;
+
+ zone->totalreserve_pages = max;
+
reserve_pages += max;
- /*
- * Lowmem reserves are not available to
- * GFP_HIGHUSER page cache allocations and
- * kswapd tries to balance zones to their high
- * watermark. As a result, neither should be
- * regarded as dirtyable memory, to prevent a
- * situation where reclaim has to clean pages
- * in order to balance the zones.
- */
- zone->dirty_balance_reserve = max;
}
}
- dirty_balance_reserve = reserve_pages;
totalreserve_pages = reserve_pages;
}
static void __setup_per_zone_wmarks(void)
{
unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
+ unsigned long pages_low = extra_free_kbytes >> (PAGE_SHIFT - 10);
unsigned long lowmem_pages = 0;
struct zone *zone;
unsigned long flags;
}
for_each_zone(zone) {
- u64 tmp;
+ u64 min, low;
spin_lock_irqsave(&zone->lock, flags);
- tmp = (u64)pages_min * zone->managed_pages;
- do_div(tmp, lowmem_pages);
+ min = (u64)pages_min * zone->managed_pages;
+ do_div(min, lowmem_pages);
+ low = (u64)pages_low * zone->managed_pages;
+ do_div(low, vm_total_pages);
+
if (is_highmem(zone)) {
/*
* __GFP_HIGH and PF_MEMALLOC allocations usually don't
* If it's a lowmem zone, reserve a number of pages
* proportionate to the zone's size.
*/
- zone->watermark[WMARK_MIN] = tmp;
+ zone->watermark[WMARK_MIN] = min;
}
- zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
- zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
+ zone->watermark[WMARK_LOW] = min_wmark_pages(zone) +
+ low + (min >> 2);
+ zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) +
+ low + (min >> 1);
__mod_zone_page_state(zone, NR_ALLOC_BATCH,
high_wmark_pages(zone) - low_wmark_pages(zone) -
/*
* min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
* that we can call two helper functions whenever min_free_kbytes
- * changes.
+ * or extra_free_kbytes changes.
*/
int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *length, loff_t *ppos)