From: Martin Hicks Date: Sat, 16 Apr 2005 22:24:08 +0000 (-0700) Subject: [PATCH] meminfo: add Cached underflow check X-Git-Tag: v2.6.12-rc3~226 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4c4c402d6caba5d938ffbbb49961659ecac709d4;p=linux-2.6 [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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c index 1d75d6ab68..a60a3b3d8a 100644 --- a/fs/proc/proc_misc.c +++ b/fs/proc/proc_misc.c @@ -126,6 +126,7 @@ static int meminfo_read_proc(char *page, char **start, off_t off, 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 @@ static int meminfo_read_proc(char *page, char **start, off_t off, 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 @@ static int meminfo_read_proc(char *page, char **start, off_t off, 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),