mm, show_mem: remove SHOW_MEM_FILTER_PAGE_COUNT

Commit 4b59e6c47309 ("mm, show_mem: suppress page counts in
non-blockable contexts") introduced SHOW_MEM_FILTER_PAGE_COUNT to
suppress PFN walks on large memory machines.  Commit c78e93630d15 ("mm:
do not walk all of system memory during show_mem") avoided a PFN walk in
the generic show_mem helper which removes the requirement for
SHOW_MEM_FILTER_PAGE_COUNT in that case.

This patch removes PFN walkers from the arch-specific implementations
that report on a per-node or per-zone granularity.  ARM and unicore32
still do a PFN walk as they report memory usage on each bank which is a
much finer granularity where the debugging information may still be of
use.  As the remaining arches doing PFN walks have relatively small
amounts of memory, this patch simply removes SHOW_MEM_FILTER_PAGE_COUNT.

[akpm@linux-foundation.org: fix parisc]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 48 insertions, 131 deletions

diff --git a/arch/ia64/mm/contig.c b/arch/ia64/mm/contig.c
index da5237d636d6..52715a71aede 100644
--- a/arch/ia64/mm/contig.c
+++ b/arch/ia64/mm/contig.c
@@ -31,74 +31,6 @@
 static unsigned long max_gap;
 #endif
 
-/**
- * show_mem - give short summary of memory stats
- *
- * Shows a simple page count of reserved and used pages in the system.
- * For discontig machines, it does this on a per-pgdat basis.
- */
-void show_mem(unsigned int filter)
-{
-        int i, total_reserved = 0;
-        int total_shared = 0, total_cached = 0;
-        unsigned long total_present = 0;
-        pg_data_t *pgdat;
-
-        printk(KERN_INFO "Mem-info:\n");
-        show_free_areas(filter);
-        printk(KERN_INFO "Node memory in pages:\n");
-        if (filter & SHOW_MEM_FILTER_PAGE_COUNT)
-                return;
-        for_each_online_pgdat(pgdat) {
-                unsigned long present;
-                unsigned long flags;
-                int shared = 0, cached = 0, reserved = 0;
-                int nid = pgdat->node_id;
-
-                if (skip_free_areas_node(filter, nid))
-                        continue;
-                pgdat_resize_lock(pgdat, &flags);
-                present = pgdat->node_present_pages;
-                for(i = 0; i < pgdat->node_spanned_pages; i++) {
-                        struct page *page;
-                        if (unlikely(i % MAX_ORDER_NR_PAGES == 0))
-                                touch_nmi_watchdog();
-                        if (pfn_valid(pgdat->node_start_pfn + i))
-                                page = pfn_to_page(pgdat->node_start_pfn + i);
-                        else {
-#ifdef CONFIG_VIRTUAL_MEM_MAP
-                                if (max_gap < LARGE_GAP)
-                                        continue;
-#endif
-                                i = vmemmap_find_next_valid_pfn(nid, i) - 1;
-                                continue;
-                        }
-                        if (PageReserved(page))
-                                reserved++;
-                        else if (PageSwapCache(page))
-                                cached++;
-                        else if (page_count(page))
-                                shared += page_count(page)-1;
-                }
-                pgdat_resize_unlock(pgdat, &flags);
-                total_present += present;
-                total_reserved += reserved;
-                total_cached += cached;
-                total_shared += shared;
-                printk(KERN_INFO "Node %4d:  RAM: %11ld, rsvd: %8d, "
-                       "shrd: %10d, swpd: %10d\n", nid,
-                       present, reserved, shared, cached);
-        }
-        printk(KERN_INFO "%ld pages of RAM\n", total_present);
-        printk(KERN_INFO "%d reserved pages\n", total_reserved);
-        printk(KERN_INFO "%d pages shared\n", total_shared);
-        printk(KERN_INFO "%d pages swap cached\n", total_cached);
-        printk(KERN_INFO "Total of %ld pages in page table cache\n",
-               quicklist_total_size());
-        printk(KERN_INFO "%ld free buffer pages\n", nr_free_buffer_pages());
-}
-
-
 /* physical address where the bootmem map is located */
 unsigned long bootmap_start;
 
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
index 2de08f4d9930..878626805369 100644
--- a/arch/ia64/mm/discontig.c
+++ b/arch/ia64/mm/discontig.c
@@ -608,69 +608,6 @@ void *per_cpu_init(void)
 #endif /* CONFIG_SMP */
 
 /**
- * show_mem - give short summary of memory stats
- *
- * Shows a simple page count of reserved and used pages in the system.
- * For discontig machines, it does this on a per-pgdat basis.
- */
-void show_mem(unsigned int filter)
-{
-        int i, total_reserved = 0;
-        int total_shared = 0, total_cached = 0;
-        unsigned long total_present = 0;
-        pg_data_t *pgdat;
-
-        printk(KERN_INFO "Mem-info:\n");
-        show_free_areas(filter);
-        if (filter & SHOW_MEM_FILTER_PAGE_COUNT)
-                return;
-        printk(KERN_INFO "Node memory in pages:\n");
-        for_each_online_pgdat(pgdat) {
-                unsigned long present;
-                unsigned long flags;
-                int shared = 0, cached = 0, reserved = 0;
-                int nid = pgdat->node_id;
-
-                if (skip_free_areas_node(filter, nid))
-                        continue;
-                pgdat_resize_lock(pgdat, &flags);
-                present = pgdat->node_present_pages;
-                for(i = 0; i < pgdat->node_spanned_pages; i++) {
-                        struct page *page;
-                        if (unlikely(i % MAX_ORDER_NR_PAGES == 0))
-                                touch_nmi_watchdog();
-                        if (pfn_valid(pgdat->node_start_pfn + i))
-                                page = pfn_to_page(pgdat->node_start_pfn + i);
-                        else {
-                                i = vmemmap_find_next_valid_pfn(nid, i) - 1;
-                                continue;
-                        }
-                        if (PageReserved(page))
-                                reserved++;
-                        else if (PageSwapCache(page))
-                                cached++;
-                        else if (page_count(page))
-                                shared += page_count(page)-1;
-                }
-                pgdat_resize_unlock(pgdat, &flags);
-                total_present += present;
-                total_reserved += reserved;
-                total_cached += cached;
-                total_shared += shared;
-                printk(KERN_INFO "Node %4d:  RAM: %11ld, rsvd: %8d, "
-                       "shrd: %10d, swpd: %10d\n", nid,
-                       present, reserved, shared, cached);
-        }
-        printk(KERN_INFO "%ld pages of RAM\n", total_present);
-        printk(KERN_INFO "%d reserved pages\n", total_reserved);
-        printk(KERN_INFO "%d pages shared\n", total_shared);
-        printk(KERN_INFO "%d pages swap cached\n", total_cached);
-        printk(KERN_INFO "Total of %ld pages in page table cache\n",
-               quicklist_total_size());
-        printk(KERN_INFO "%ld free buffer pages\n", nr_free_buffer_pages());
-}
-
-/**
  * call_pernode_memory - use SRAT to call callback functions with node info
  * @start: physical start of range
  * @len: length of range
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index 88504abf5704..25c350264a41 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -684,3 +684,51 @@ per_linux32_init(void)
 }
 
 __initcall(per_linux32_init);
+
+/**
+ * show_mem - give short summary of memory stats
+ *
+ * Shows a simple page count of reserved and used pages in the system.
+ * For discontig machines, it does this on a per-pgdat basis.
+ */
+void show_mem(unsigned int filter)
+{
+        int total_reserved = 0;
+        unsigned long total_present = 0;
+        pg_data_t *pgdat;
+
+        printk(KERN_INFO "Mem-info:\n");
+        show_free_areas(filter);
+        printk(KERN_INFO "Node memory in pages:\n");
+        for_each_online_pgdat(pgdat) {
+                unsigned long present;
+                unsigned long flags;
+                int reserved = 0;
+                int nid = pgdat->node_id;
+                int zoneid;
+
+                if (skip_free_areas_node(filter, nid))
+                        continue;
+                pgdat_resize_lock(pgdat, &flags);
+
+                for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
+                        struct zone *zone = &pgdat->node_zones[zoneid];
+                        if (!populated_zone(zone))
+                                continue;
+
+                        reserved += zone->present_pages - zone->managed_pages;
+                }
+                present = pgdat->node_present_pages;
+
+                pgdat_resize_unlock(pgdat, &flags);
+                total_present += present;
+                total_reserved += reserved;
+                printk(KERN_INFO "Node %4d:  RAM: %11ld, rsvd: %8d, ",
+                       nid, present, reserved);
+        }
+        printk(KERN_INFO "%ld pages of RAM\n", total_present);
+        printk(KERN_INFO "%d reserved pages\n", total_reserved);
+        printk(KERN_INFO "Total of %ld pages in page table cache\n",
+               quicklist_total_size());
+        printk(KERN_INFO "%ld free buffer pages\n", nr_free_buffer_pages());
+}