Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo
This patch provides fragmentation avoidance statistics via /proc/pagetypeinfo.
The information is collected only on request so there is no runtime overhead.
The statistics are in three parts:
The first part prints information on the size of blocks that pages are
being grouped on and looks like
Page block order: 10
Pages per block: 1024
The second part is a more detailed version of /proc/buddyinfo and looks like
Free pages count per migrate type at order 0 1 2 3 4 5 6 7 8 9 10
Node 0, zone DMA, type Unmovable 0 0 0 0 0 0 0 0 0 0 0
Node 0, zone DMA, type Reclaimable 1 0 0 0 0 0 0 0 0 0 0
Node 0, zone DMA, type Movable 0 0 0 0 0 0 0 0 0 0 0
Node 0, zone DMA, type Reserve 0 4 4 0 0 0 0 1 0 1 0
Node 0, zone Normal, type Unmovable 111 8 4 4 2 3 1 0 0 0 0
Node 0, zone Normal, type Reclaimable 293 89 8 0 0 0 0 0 0 0 0
Node 0, zone Normal, type Movable 1 6 13 9 7 6 3 0 0 0 0
Node 0, zone Normal, type Reserve 0 0 0 0 0 0 0 0 0 0 4
The third part looks like
Number of blocks type Unmovable Reclaimable Movable Reserve
Node 0, zone DMA 0 1 2 1
Node 0, zone Normal 3 17 94 4
To walk the zones within a node with interrupts disabled, walk_zones_in_node()
is introduced and shared between /proc/buddyinfo, /proc/zoneinfo and
/proc/pagetypeinfo to reduce code duplication. It seems specific to what
vmstat.c requires but could be broken out as a general utility function in
mmzone.c if there were other other potential users.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 0071939..5de7f87 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -229,6 +229,19 @@
.release = seq_release,
};
+extern struct seq_operations pagetypeinfo_op;
+static int pagetypeinfo_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &pagetypeinfo_op);
+}
+
+static const struct file_operations pagetypeinfo_file_ops = {
+ .open = pagetypeinfo_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
extern struct seq_operations zoneinfo_op;
static int zoneinfo_open(struct inode *inode, struct file *file)
{
@@ -724,6 +737,7 @@
#endif
#endif
create_seq_entry("buddyinfo",S_IRUGO, &fragmentation_file_operations);
+ create_seq_entry("pagetypeinfo", S_IRUGO, &pagetypeinfo_file_ops);
create_seq_entry("vmstat",S_IRUGO, &proc_vmstat_file_operations);
create_seq_entry("zoneinfo",S_IRUGO, &proc_zoneinfo_file_operations);
#ifdef CONFIG_BLOCK
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index f8ffcd4..7e93a9a 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -104,6 +104,18 @@
/* 4GB DMA on some platforms */
#define GFP_DMA32 __GFP_DMA32
+/* Convert GFP flags to their corresponding migrate type */
+static inline int allocflags_to_migratetype(gfp_t gfp_flags)
+{
+ WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
+
+ if (unlikely(page_group_by_mobility_disabled))
+ return MIGRATE_UNMOVABLE;
+
+ /* Group based on mobility */
+ return (((gfp_flags & __GFP_MOVABLE) != 0) << 1) |
+ ((gfp_flags & __GFP_RECLAIMABLE) != 0);
+}
static inline enum zone_type gfp_zone(gfp_t flags)
{
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 87a4045..20ea42c 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -43,6 +43,16 @@
for (order = 0; order < MAX_ORDER; order++) \
for (type = 0; type < MIGRATE_TYPES; type++)
+extern int page_group_by_mobility_disabled;
+
+static inline int get_pageblock_migratetype(struct page *page)
+{
+ if (unlikely(page_group_by_mobility_disabled))
+ return MIGRATE_UNMOVABLE;
+
+ return get_pageblock_flags_group(page, PB_migrate, PB_migrate_end);
+}
+
struct free_area {
struct list_head free_list[MIGRATE_TYPES];
unsigned long nr_free;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index b9bc736..17797d0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -164,32 +164,12 @@
int page_group_by_mobility_disabled __read_mostly;
-static inline int get_pageblock_migratetype(struct page *page)
-{
- if (unlikely(page_group_by_mobility_disabled))
- return MIGRATE_UNMOVABLE;
-
- return get_pageblock_flags_group(page, PB_migrate, PB_migrate_end);
-}
-
static void set_pageblock_migratetype(struct page *page, int migratetype)
{
set_pageblock_flags_group(page, (unsigned long)migratetype,
PB_migrate, PB_migrate_end);
}
-static inline int allocflags_to_migratetype(gfp_t gfp_flags)
-{
- WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
-
- if (unlikely(page_group_by_mobility_disabled))
- return MIGRATE_UNMOVABLE;
-
- /* Cluster based on mobility */
- return (((gfp_flags & __GFP_MOVABLE) != 0) << 1) |
- ((gfp_flags & __GFP_RECLAIMABLE) != 0);
-}
-
#ifdef CONFIG_DEBUG_VM
static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
{
diff --git a/mm/vmstat.c b/mm/vmstat.c
index c64d169..2f19e4f 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -398,6 +398,13 @@
#include <linux/seq_file.h>
+static char * const migratetype_names[MIGRATE_TYPES] = {
+ "Unmovable",
+ "Reclaimable",
+ "Movable",
+ "Reserve",
+};
+
static void *frag_start(struct seq_file *m, loff_t *pos)
{
pg_data_t *pgdat;
@@ -422,28 +429,144 @@
{
}
-/*
- * This walks the free areas for each zone.
- */
-static int frag_show(struct seq_file *m, void *arg)
+/* Walk all the zones in a node and print using a callback */
+static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
+ void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
{
- pg_data_t *pgdat = (pg_data_t *)arg;
struct zone *zone;
struct zone *node_zones = pgdat->node_zones;
unsigned long flags;
- int order;
for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
if (!populated_zone(zone))
continue;
spin_lock_irqsave(&zone->lock, flags);
- seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
- for (order = 0; order < MAX_ORDER; ++order)
- seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
+ print(m, pgdat, zone);
spin_unlock_irqrestore(&zone->lock, flags);
+ }
+}
+
+static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
+ struct zone *zone)
+{
+ int order;
+
+ seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
+ for (order = 0; order < MAX_ORDER; ++order)
+ seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
+ seq_putc(m, '\n');
+}
+
+/*
+ * This walks the free areas for each zone.
+ */
+static int frag_show(struct seq_file *m, void *arg)
+{
+ pg_data_t *pgdat = (pg_data_t *)arg;
+ walk_zones_in_node(m, pgdat, frag_show_print);
+ return 0;
+}
+
+static void pagetypeinfo_showfree_print(struct seq_file *m,
+ pg_data_t *pgdat, struct zone *zone)
+{
+ int order, mtype;
+
+ for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
+ seq_printf(m, "Node %4d, zone %8s, type %12s ",
+ pgdat->node_id,
+ zone->name,
+ migratetype_names[mtype]);
+ for (order = 0; order < MAX_ORDER; ++order) {
+ unsigned long freecount = 0;
+ struct free_area *area;
+ struct list_head *curr;
+
+ area = &(zone->free_area[order]);
+
+ list_for_each(curr, &area->free_list[mtype])
+ freecount++;
+ seq_printf(m, "%6lu ", freecount);
+ }
seq_putc(m, '\n');
}
+}
+
+/* Print out the free pages at each order for each migatetype */
+static int pagetypeinfo_showfree(struct seq_file *m, void *arg)
+{
+ int order;
+ pg_data_t *pgdat = (pg_data_t *)arg;
+
+ /* Print header */
+ seq_printf(m, "%-43s ", "Free pages count per migrate type at order");
+ for (order = 0; order < MAX_ORDER; ++order)
+ seq_printf(m, "%6d ", order);
+ seq_putc(m, '\n');
+
+ walk_zones_in_node(m, pgdat, pagetypeinfo_showfree_print);
+
+ return 0;
+}
+
+static void pagetypeinfo_showblockcount_print(struct seq_file *m,
+ pg_data_t *pgdat, struct zone *zone)
+{
+ int mtype;
+ unsigned long pfn;
+ unsigned long start_pfn = zone->zone_start_pfn;
+ unsigned long end_pfn = start_pfn + zone->spanned_pages;
+ unsigned long count[MIGRATE_TYPES] = { 0, };
+
+ for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
+ struct page *page;
+
+ if (!pfn_valid(pfn))
+ continue;
+
+ page = pfn_to_page(pfn);
+ mtype = get_pageblock_migratetype(page);
+
+ count[mtype]++;
+ }
+
+ /* Print counts */
+ seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
+ for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
+ seq_printf(m, "%12lu ", count[mtype]);
+ seq_putc(m, '\n');
+}
+
+/* Print out the free pages at each order for each migratetype */
+static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
+{
+ int mtype;
+ pg_data_t *pgdat = (pg_data_t *)arg;
+
+ seq_printf(m, "\n%-23s", "Number of blocks type ");
+ for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
+ seq_printf(m, "%12s ", migratetype_names[mtype]);
+ seq_putc(m, '\n');
+ walk_zones_in_node(m, pgdat, pagetypeinfo_showblockcount_print);
+
+ return 0;
+}
+
+/*
+ * This prints out statistics in relation to grouping pages by mobility.
+ * It is expensive to collect so do not constantly read the file.
+ */
+static int pagetypeinfo_show(struct seq_file *m, void *arg)
+{
+ pg_data_t *pgdat = (pg_data_t *)arg;
+
+ seq_printf(m, "Page block order: %d\n", pageblock_order);
+ seq_printf(m, "Pages per block: %lu\n", pageblock_nr_pages);
+ seq_putc(m, '\n');
+ pagetypeinfo_showfree(m, pgdat);
+ pagetypeinfo_showblockcount(m, pgdat);
+
return 0;
}
@@ -454,6 +577,13 @@
.show = frag_show,
};
+const struct seq_operations pagetypeinfo_op = {
+ .start = frag_start,
+ .next = frag_next,
+ .stop = frag_stop,
+ .show = pagetypeinfo_show,
+};
+
#ifdef CONFIG_ZONE_DMA
#define TEXT_FOR_DMA(xx) xx "_dma",
#else
@@ -532,84 +662,78 @@
#endif
};
+static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
+ struct zone *zone)
+{
+ int i;
+ seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
+ seq_printf(m,
+ "\n pages free %lu"
+ "\n min %lu"
+ "\n low %lu"
+ "\n high %lu"
+ "\n scanned %lu (a: %lu i: %lu)"
+ "\n spanned %lu"
+ "\n present %lu",
+ zone_page_state(zone, NR_FREE_PAGES),
+ zone->pages_min,
+ zone->pages_low,
+ zone->pages_high,
+ zone->pages_scanned,
+ zone->nr_scan_active, zone->nr_scan_inactive,
+ zone->spanned_pages,
+ zone->present_pages);
+
+ for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
+ seq_printf(m, "\n %-12s %lu", vmstat_text[i],
+ zone_page_state(zone, i));
+
+ seq_printf(m,
+ "\n protection: (%lu",
+ zone->lowmem_reserve[0]);
+ for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
+ seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
+ seq_printf(m,
+ ")"
+ "\n pagesets");
+ for_each_online_cpu(i) {
+ struct per_cpu_pageset *pageset;
+ int j;
+
+ pageset = zone_pcp(zone, i);
+ for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
+ seq_printf(m,
+ "\n cpu: %i pcp: %i"
+ "\n count: %i"
+ "\n high: %i"
+ "\n batch: %i",
+ i, j,
+ pageset->pcp[j].count,
+ pageset->pcp[j].high,
+ pageset->pcp[j].batch);
+ }
+#ifdef CONFIG_SMP
+ seq_printf(m, "\n vm stats threshold: %d",
+ pageset->stat_threshold);
+#endif
+ }
+ seq_printf(m,
+ "\n all_unreclaimable: %u"
+ "\n prev_priority: %i"
+ "\n start_pfn: %lu",
+ zone->all_unreclaimable,
+ zone->prev_priority,
+ zone->zone_start_pfn);
+ seq_putc(m, '\n');
+}
+
/*
* Output information about zones in @pgdat.
*/
static int zoneinfo_show(struct seq_file *m, void *arg)
{
- pg_data_t *pgdat = arg;
- struct zone *zone;
- struct zone *node_zones = pgdat->node_zones;
- unsigned long flags;
-
- for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; zone++) {
- int i;
-
- if (!populated_zone(zone))
- continue;
-
- spin_lock_irqsave(&zone->lock, flags);
- seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
- seq_printf(m,
- "\n pages free %lu"
- "\n min %lu"
- "\n low %lu"
- "\n high %lu"
- "\n scanned %lu (a: %lu i: %lu)"
- "\n spanned %lu"
- "\n present %lu",
- zone_page_state(zone, NR_FREE_PAGES),
- zone->pages_min,
- zone->pages_low,
- zone->pages_high,
- zone->pages_scanned,
- zone->nr_scan_active, zone->nr_scan_inactive,
- zone->spanned_pages,
- zone->present_pages);
-
- for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
- seq_printf(m, "\n %-12s %lu", vmstat_text[i],
- zone_page_state(zone, i));
-
- seq_printf(m,
- "\n protection: (%lu",
- zone->lowmem_reserve[0]);
- for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
- seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
- seq_printf(m,
- ")"
- "\n pagesets");
- for_each_online_cpu(i) {
- struct per_cpu_pageset *pageset;
- int j;
-
- pageset = zone_pcp(zone, i);
- for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
- seq_printf(m,
- "\n cpu: %i pcp: %i"
- "\n count: %i"
- "\n high: %i"
- "\n batch: %i",
- i, j,
- pageset->pcp[j].count,
- pageset->pcp[j].high,
- pageset->pcp[j].batch);
- }
-#ifdef CONFIG_SMP
- seq_printf(m, "\n vm stats threshold: %d",
- pageset->stat_threshold);
-#endif
- }
- seq_printf(m,
- "\n all_unreclaimable: %u"
- "\n prev_priority: %i"
- "\n start_pfn: %lu",
- zone->all_unreclaimable,
- zone->prev_priority,
- zone->zone_start_pfn);
- spin_unlock_irqrestore(&zone->lock, flags);
- seq_putc(m, '\n');
- }
+ pg_data_t *pgdat = (pg_data_t *)arg;
+ walk_zones_in_node(m, pgdat, zoneinfo_show_print);
return 0;
}
