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Diffstat (limited to 'mm/page_alloc.c')
-rw-r--r--mm/page_alloc.c60
1 files changed, 59 insertions, 1 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 26c9939857f..8d9a1eb9fbb 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -104,6 +104,7 @@ int min_free_kbytes = 1024;
unsigned long __meminitdata nr_kernel_pages;
unsigned long __meminitdata nr_all_pages;
+static unsigned long __initdata dma_reserve;
#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
/*
@@ -2213,6 +2214,20 @@ unsigned long __init zone_absent_pages_in_node(int nid,
arch_zone_lowest_possible_pfn[zone_type],
arch_zone_highest_possible_pfn[zone_type]);
}
+
+/* Return the zone index a PFN is in */
+int memmap_zone_idx(struct page *lmem_map)
+{
+ int i;
+ unsigned long phys_addr = virt_to_phys(lmem_map);
+ unsigned long pfn = phys_addr >> PAGE_SHIFT;
+
+ for (i = 0; i < MAX_NR_ZONES; i++)
+ if (pfn < arch_zone_highest_possible_pfn[i])
+ break;
+
+ return i;
+}
#else
static inline unsigned long zone_spanned_pages_in_node(int nid,
unsigned long zone_type,
@@ -2230,6 +2245,11 @@ static inline unsigned long zone_absent_pages_in_node(int nid,
return zholes_size[zone_type];
}
+
+static inline int memmap_zone_idx(struct page *lmem_map)
+{
+ return MAX_NR_ZONES;
+}
#endif
static void __init calculate_node_totalpages(struct pglist_data *pgdat,
@@ -2274,12 +2294,35 @@ static void __meminit free_area_init_core(struct pglist_data *pgdat,
for (j = 0; j < MAX_NR_ZONES; j++) {
struct zone *zone = pgdat->node_zones + j;
- unsigned long size, realsize;
+ unsigned long size, realsize, memmap_pages;
size = zone_spanned_pages_in_node(nid, j, zones_size);
realsize = size - zone_absent_pages_in_node(nid, j,
zholes_size);
+ /*
+ * Adjust realsize so that it accounts for how much memory
+ * is used by this zone for memmap. This affects the watermark
+ * and per-cpu initialisations
+ */
+ memmap_pages = (size * sizeof(struct page)) >> PAGE_SHIFT;
+ if (realsize >= memmap_pages) {
+ realsize -= memmap_pages;
+ printk(KERN_DEBUG
+ " %s zone: %lu pages used for memmap\n",
+ zone_names[j], memmap_pages);
+ } else
+ printk(KERN_WARNING
+ " %s zone: %lu pages exceeds realsize %lu\n",
+ zone_names[j], memmap_pages, realsize);
+
+ /* Account for reserved DMA pages */
+ if (j == ZONE_DMA && realsize > dma_reserve) {
+ realsize -= dma_reserve;
+ printk(KERN_DEBUG " DMA zone: %lu pages reserved\n",
+ dma_reserve);
+ }
+
if (!is_highmem_idx(j))
nr_kernel_pages += realsize;
nr_all_pages += realsize;
@@ -2596,6 +2639,21 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
}
#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
+/**
+ * set_dma_reserve - Account the specified number of pages reserved in ZONE_DMA
+ * @new_dma_reserve - The number of pages to mark reserved
+ *
+ * The per-cpu batchsize and zone watermarks are determined by present_pages.
+ * In the DMA zone, a significant percentage may be consumed by kernel image
+ * and other unfreeable allocations which can skew the watermarks badly. This
+ * function may optionally be used to account for unfreeable pages in
+ * ZONE_DMA. The effect will be lower watermarks and smaller per-cpu batchsize
+ */
+void __init set_dma_reserve(unsigned long new_dma_reserve)
+{
+ dma_reserve = new_dma_reserve;
+}
+
#ifndef CONFIG_NEED_MULTIPLE_NODES
static bootmem_data_t contig_bootmem_data;
struct pglist_data contig_page_data = { .bdata = &contig_bootmem_data };