[PATCH] meminfo: add Cached underflow check
Working on some code lately I've been getting huge values for "Cached".
The cause is that get_page_cache_size() is an approximate value, and for a
sufficiently small returned value of get_page_cache_size() the value
underflows.
Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 1d75d6a..a60a3b3 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -126,6 +126,7 @@
unsigned long committed;
unsigned long allowed;
struct vmalloc_info vmi;
+ long cached;
get_page_state(&ps);
get_zone_counts(&active, &inactive, &free);
@@ -140,6 +141,10 @@
allowed = ((totalram_pages - hugetlb_total_pages())
* sysctl_overcommit_ratio / 100) + total_swap_pages;
+ cached = get_page_cache_size() - total_swapcache_pages - i.bufferram;
+ if (cached < 0)
+ cached = 0;
+
get_vmalloc_info(&vmi);
/*
@@ -172,7 +177,7 @@
K(i.totalram),
K(i.freeram),
K(i.bufferram),
- K(get_page_cache_size()-total_swapcache_pages-i.bufferram),
+ K(cached),
K(total_swapcache_pages),
K(active),
K(inactive),