* NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
* HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
* HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
+ *
+ * TBD: should special case ZONE_DMA32 machines here - in those we normally
+ * don't need any ZONE_NORMAL reservation
*/
-int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { 256, 32 };
+int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { 256, 256, 32 };
EXPORT_SYMBOL(totalram_pages);
struct zone *zone_table[1 << ZONETABLE_SHIFT] __read_mostly;
EXPORT_SYMBOL(zone_table);
-static char *zone_names[MAX_NR_ZONES] = { "DMA", "Normal", "HighMem" };
+static char *zone_names[MAX_NR_ZONES] = { "DMA", "DMA32", "Normal", "HighMem" };
int min_free_kbytes = 1024;
unsigned long __initdata nr_kernel_pages;
printk(KERN_EMERG "Bad page state at %s (in process '%s', page %p)\n",
function, current->comm, page);
printk(KERN_EMERG "flags:0x%0*lx mapping:%p mapcount:%d count:%d\n",
- (int)(2*sizeof(page_flags_t)), (unsigned long)page->flags,
+ (int)(2*sizeof(unsigned long)), (unsigned long)page->flags,
page->mapping, page_mapcount(page), page_count(page));
printk(KERN_EMERG "Backtrace:\n");
dump_stack();
1 << PG_reclaim |
1 << PG_slab |
1 << PG_swapcache |
- 1 << PG_writeback |
- 1 << PG_reserved );
+ 1 << PG_writeback );
set_page_count(page, 0);
reset_page_mapcount(page);
page->mapping = NULL;
add_taint(TAINT_BAD_PAGE);
}
-#ifndef CONFIG_HUGETLB_PAGE
-#define prep_compound_page(page, order) do { } while (0)
-#define destroy_compound_page(page, order) do { } while (0)
-#else
/*
* Higher-order pages are called "compound pages". They are structured thusly:
*
ClearPageCompound(p);
}
}
-#endif /* CONFIG_HUGETLB_PAGE */
/*
* function for dealing with page's order in buddy system.
zone->free_area[order].nr_free++;
}
-static inline void free_pages_check(const char *function, struct page *page)
+static inline int free_pages_check(const char *function, struct page *page)
{
if ( page_mapcount(page) ||
page->mapping != NULL ||
bad_page(function, page);
if (PageDirty(page))
__ClearPageDirty(page);
+ /*
+ * For now, we report if PG_reserved was found set, but do not
+ * clear it, and do not free the page. But we shall soon need
+ * to do more, for when the ZERO_PAGE count wraps negative.
+ */
+ return PageReserved(page);
}
/*
{
LIST_HEAD(list);
int i;
+ int reserved = 0;
arch_free_page(page, order);
- mod_page_state(pgfree, 1 << order);
-
#ifndef CONFIG_MMU
if (order > 0)
for (i = 1 ; i < (1 << order) ; ++i)
#endif
for (i = 0 ; i < (1 << order) ; ++i)
- free_pages_check(__FUNCTION__, page + i);
+ reserved += free_pages_check(__FUNCTION__, page + i);
+ if (reserved)
+ return;
+
list_add(&page->lru, &list);
+ mod_page_state(pgfree, 1 << order);
kernel_map_pages(page, 1<<order, 0);
free_pages_bulk(page_zone(page), 1, &list, order);
}
/*
* This page is about to be returned from the page allocator
*/
-static void prep_new_page(struct page *page, int order)
+static int prep_new_page(struct page *page, int order)
{
if ( page_mapcount(page) ||
page->mapping != NULL ||
1 << PG_reserved )))
bad_page(__FUNCTION__, page);
+ /*
+ * For now, we report if PG_reserved was found set, but do not
+ * clear it, and do not allocate the page: as a safety net.
+ */
+ if (PageReserved(page))
+ return 1;
+
page->flags &= ~(1 << PG_uptodate | 1 << PG_error |
1 << PG_referenced | 1 << PG_arch_1 |
1 << PG_checked | 1 << PG_mappedtodisk);
set_page_private(page, 0);
set_page_refs(page, order);
kernel_map_pages(page, 1 << order, 1);
+ return 0;
}
/*
arch_free_page(page, 0);
- kernel_map_pages(page, 1, 0);
- inc_page_state(pgfree);
if (PageAnon(page))
page->mapping = NULL;
- free_pages_check(__FUNCTION__, page);
+ if (free_pages_check(__FUNCTION__, page))
+ return;
+
+ inc_page_state(pgfree);
+ kernel_map_pages(page, 1, 0);
+
pcp = &zone_pcp(zone, get_cpu())->pcp[cold];
local_irq_save(flags);
list_add(&page->lru, &pcp->list);
buffered_rmqueue(struct zone *zone, int order, gfp_t gfp_flags)
{
unsigned long flags;
- struct page *page = NULL;
+ struct page *page;
int cold = !!(gfp_flags & __GFP_COLD);
+again:
if (order == 0) {
struct per_cpu_pages *pcp;
+ page = NULL;
pcp = &zone_pcp(zone, get_cpu())->pcp[cold];
local_irq_save(flags);
if (pcp->count <= pcp->low)
if (page != NULL) {
BUG_ON(bad_range(zone, page));
mod_page_state_zone(zone, pgalloc, 1 << order);
- prep_new_page(page, order);
+ if (prep_new_page(page, order))
+ goto again;
if (gfp_flags & __GFP_ZERO)
prep_zero_page(page, order, gfp_flags);
}
#define ALLOC_NO_WATERMARKS 0x01 /* don't check watermarks at all */
-#define ALLOC_HARDER 0x02 /* try to alloc harder */
-#define ALLOC_HIGH 0x04 /* __GFP_HIGH set */
-#define ALLOC_CPUSET 0x08 /* check for correct cpuset */
+#define ALLOC_WMARK_MIN 0x02 /* use pages_min watermark */
+#define ALLOC_WMARK_LOW 0x04 /* use pages_low watermark */
+#define ALLOC_WMARK_HIGH 0x08 /* use pages_high watermark */
+#define ALLOC_HARDER 0x10 /* try to alloc harder */
+#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
+#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
/*
* Return 1 if free pages are above 'mark'. This takes into account the order
continue;
if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
- if (!zone_watermark_ok(*z, order, (*z)->pages_low,
+ unsigned long mark;
+ if (alloc_flags & ALLOC_WMARK_MIN)
+ mark = (*z)->pages_min;
+ else if (alloc_flags & ALLOC_WMARK_LOW)
+ mark = (*z)->pages_low;
+ else
+ mark = (*z)->pages_high;
+ if (!zone_watermark_ok(*z, order, mark,
classzone_idx, alloc_flags))
continue;
}
might_sleep_if(wait);
+restart:
z = zonelist->zones; /* the list of zones suitable for gfp_mask */
if (unlikely(*z == NULL)) {
/* Should this ever happen?? */
return NULL;
}
-restart:
+
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
- zonelist, ALLOC_CPUSET);
+ zonelist, ALLOC_WMARK_LOW|ALLOC_CPUSET);
if (page)
goto got_pg;
- do
+ do {
wakeup_kswapd(*z, order);
- while (*(++z));
+ } while (*(++z));
/*
* OK, we're below the kswapd watermark and have kicked background
* cannot run direct reclaim, or if the caller has realtime scheduling
* policy.
*/
- alloc_flags = 0;
+ alloc_flags = ALLOC_WMARK_MIN;
if ((unlikely(rt_task(p)) && !in_interrupt()) || !wait)
alloc_flags |= ALLOC_HARDER;
if (gfp_mask & __GFP_HIGH)
* under heavy pressure.
*/
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
- zonelist, ALLOC_CPUSET);
+ zonelist, ALLOC_WMARK_HIGH|ALLOC_CPUSET);
if (page)
goto got_pg;
zone = pgdat->node_zones + ZONE_NORMAL;
if (zone->present_pages)
zonelist->zones[j++] = zone;
+ case ZONE_DMA32:
+ zone = pgdat->node_zones + ZONE_DMA32;
+ if (zone->present_pages)
+ zonelist->zones[j++] = zone;
case ZONE_DMA:
zone = pgdat->node_zones + ZONE_DMA;
if (zone->present_pages)
int res = ZONE_NORMAL;
if (zone_bits & (__force int)__GFP_HIGHMEM)
res = ZONE_HIGHMEM;
+ if (zone_bits & (__force int)__GFP_DMA32)
+ res = ZONE_DMA32;
if (zone_bits & (__force int)__GFP_DMA)
res = ZONE_DMA;
return res;
batch = 1;
/*
- * We will be trying to allcoate bigger chunks of contiguous
- * memory of the order of fls(batch). This should result in
- * better cache coloring.
+ * Clamp the batch to a 2^n - 1 value. Having a power
+ * of 2 value was found to be more likely to have
+ * suboptimal cache aliasing properties in some cases.
*
- * A sanity check also to ensure that batch is still in limits.
+ * For example if 2 tasks are alternately allocating
+ * batches of pages, one task can end up with a lot
+ * of pages of one half of the possible page colors
+ * and the other with pages of the other colors.
*/
- batch = (1 << fls(batch + batch/2));
-
- if (fls(batch) >= (PAGE_SHIFT + MAX_ORDER - 2))
- batch = PAGE_SHIFT + ((MAX_ORDER - 1 - PAGE_SHIFT)/2);
+ batch = (1 << (fls(batch + batch/2)-1)) - 1;
return batch;
}
if (process_zones(cpu))
ret = NOTIFY_BAD;
break;
-#ifdef CONFIG_HOTPLUG_CPU
+ case CPU_UP_CANCELED:
case CPU_DEAD:
free_zone_pagesets(cpu);
break;
-#endif
default:
break;
}
if (zholes_size)
realsize -= zholes_size[j];
- if (j == ZONE_DMA || j == ZONE_NORMAL)
+ if (j < ZONE_HIGHMEM)
nr_kernel_pages += realsize;
nr_all_pages += realsize;