From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262228AbVDLSC2 (ORCPT ); Tue, 12 Apr 2005 14:02:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262223AbVDLKcl (ORCPT ); Tue, 12 Apr 2005 06:32:41 -0400 Received: from fire.osdl.org ([65.172.181.4]:61895 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S262113AbVDLKbC (ORCPT ); Tue, 12 Apr 2005 06:31:02 -0400 Message-Id: <200504121030.j3CAUuSd005187@shell0.pdx.osdl.net> Subject: [patch 019/198] meminfo: add Cached underflow check To: torvalds@osdl.org Cc: linux-kernel@vger.kernel.org, akpm@osdl.org, mort@sgi.com From: akpm@osdl.org Date: Tue, 12 Apr 2005 03:30:50 -0700 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Martin Hicks 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 --- 25-akpm/fs/proc/proc_misc.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletion(-) diff -puN fs/proc/proc_misc.c~meminfo-add-cached-underflow-check fs/proc/proc_misc.c --- 25/fs/proc/proc_misc.c~meminfo-add-cached-underflow-check 2005-04-12 03:21:07.910934256 -0700 +++ 25-akpm/fs/proc/proc_misc.c 2005-04-12 03:21:07.914933648 -0700 @@ -126,6 +126,7 @@ static int meminfo_read_proc(char *page, 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, 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, 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), _