KOSAKI Motohiro 00a62ce91e mm: fix Committed_AS underflow on large NR_CPUS environment ... The Committed_AS field can underflow in certain situations: > # while true; do cat /proc/meminfo | grep _AS; sleep 1; done | uniq -c > 1 Committed_AS: 18446744073709323392 kB > 11 Committed_AS: 18446744073709455488 kB > 6 Committed_AS: 35136 kB > 5 Committed_AS: 18446744073709454400 kB > 7 Committed_AS: 35904 kB > 3 Committed_AS: 18446744073709453248 kB > 2 Committed_AS: 34752 kB > 9 Committed_AS: 18446744073709453248 kB > 8 Committed_AS: 34752 kB > 3 Committed_AS: 18446744073709320960 kB > 7 Committed_AS: 18446744073709454080 kB > 3 Committed_AS: 18446744073709320960 kB > 5 Committed_AS: 18446744073709454080 kB > 6 Committed_AS: 18446744073709320960 kB Because NR_CPUS can be greater than 1000 and meminfo_proc_show() does not check for underflow. But NR_CPUS proportional isn't good calculation. In general, possibility of lock contention is proportional to the number of online cpus, not theorical maximum cpus (NR_CPUS). The current kernel has generic percpu-counter stuff. using it is right way. it makes code simplify and percpu_counter_read_positive() don't make underflow issue. Reported-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Eric B Munson <ebmunson@us.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: <stable@kernel.org> [All kernel versions] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2009-05-02 15:36:10 -07:00
..
array.c
base.c	proc: mounts_poll() make consistent to mdstat_poll	2009-04-16 16:17:10 -07:00
cmdline.c
cpuinfo.c
devices.c
generic.c	proc 1/2: do PDE usecounting even for ->read_proc, ->write_proc	2009-03-31 01:14:27 +04:00
inode.c	proc 2/2: remove struct proc_dir_entry::owner	2009-03-31 01:14:44 +04:00
internal.h	proc 1/2: do PDE usecounting even for ->read_proc, ->write_proc	2009-03-31 01:14:27 +04:00
interrupts.c
Kconfig
kcore.c
kmsg.c
loadavg.c
Makefile
meminfo.c	mm: fix Committed_AS underflow on large NR_CPUS environment	2009-05-02 15:36:10 -07:00
mmu.c
nommu.c	trivial: fix typo "kernal" -> "kernel"	2009-03-30 15:21:57 +02:00
page.c	proc: fix kflags to uflags copying in /proc/kpageflags	2009-03-11 07:43:33 -07:00
proc_devtree.c
proc_net.c
proc_sysctl.c	constify dentry_operations: procfs	2009-03-27 14:44:01 -04:00
proc_tty.c	proc tty: remove struct tty_operations::read_proc	2009-04-01 08:59:10 -07:00
root.c	vfs: simple_set_mnt() should return void	2009-03-27 14:44:03 -04:00
stat.c	[S390] /proc/stat idle field for idle cpus	2009-04-23 13:58:17 +02:00
task_mmu.c	pagemap: require aligned-length, non-null reads of /proc/pid/pagemap	2009-05-02 15:36:09 -07:00
task_nommu.c	nommu: fix typo vma->pg_off to vma->vm_pgoff	2009-04-08 10:21:44 -07:00
uptime.c	Revert "proc: revert /proc/uptime to ->read_proc hook"	2009-03-31 01:14:58 +04:00
version.c
vmcore.c