[PATCH] VM: add page_state info to per-node meminfo

Add page_state info to the per-node meminfo file in sysfs.  This is mostly
just for informational purposes.

The lack of this information was brought up recently during a discussion
regarding pagecache clearing, and I put this patch together to test out one
of the suggestions.

It seems like interesting info to have, so I'm submitting the patch.

Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 20 insertions, 5 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d157dae8c9f..b06a9636d97 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1130,19 +1130,20 @@ EXPORT_SYMBOL(nr_pagecache);
 DEFINE_PER_CPU(long, nr_pagecache_local) = 0;
 #endif
 
-void __get_page_state(struct page_state *ret, int nr)
+void __get_page_state(struct page_state *ret, int nr, cpumask_t *cpumask)
 {
         int cpu = 0;
 
         memset(ret, 0, sizeof(*ret));
+        cpus_and(*cpumask, *cpumask, cpu_online_map);
 
-        cpu = first_cpu(cpu_online_map);
+        cpu = first_cpu(*cpumask);
         while (cpu < NR_CPUS) {
                 unsigned long *in, *out, off;
 
                 in = (unsigned long *)&per_cpu(page_states, cpu);
 
-                cpu = next_cpu(cpu, cpu_online_map);
+                cpu = next_cpu(cpu, *cpumask);
 
                 if (cpu < NR_CPUS)
                         prefetch(&per_cpu(page_states, cpu));
@@ -1153,19 +1154,33 @@ void __get_page_state(struct page_state *ret, int nr)
         }
 }
 
+void get_page_state_node(struct page_state *ret, int node)
+{
+        int nr;
+        cpumask_t mask = node_to_cpumask(node);
+
+        nr = offsetof(struct page_state, GET_PAGE_STATE_LAST);
+        nr /= sizeof(unsigned long);
+
+        __get_page_state(ret, nr+1, &mask);
+}
+
 void get_page_state(struct page_state *ret)
 {
         int nr;
+        cpumask_t mask = CPU_MASK_ALL;
 
         nr = offsetof(struct page_state, GET_PAGE_STATE_LAST);
         nr /= sizeof(unsigned long);
 
-        __get_page_state(ret, nr + 1);
+        __get_page_state(ret, nr + 1, &mask);
 }
 
 void get_full_page_state(struct page_state *ret)
 {
-        __get_page_state(ret, sizeof(*ret) / sizeof(unsigned long));
+        cpumask_t mask = CPU_MASK_ALL;
+
+        __get_page_state(ret, sizeof(*ret) / sizeof(unsigned long), &mask);
 }
 
 unsigned long __read_page_state(unsigned long offset)