[PATCH] Represent dirty_*_centisecs as jiffies internally
authorBart Samwel <bart@samwel.tk>
Fri, 24 Mar 2006 11:15:48 +0000 (03:15 -0800)
committerLinus Torvalds <torvalds@g5.osdl.org>
Fri, 24 Mar 2006 15:33:20 +0000 (07:33 -0800)
commitf6ef943813ac3085ece7252ea101d663581219f6
treee32d3e57ba6ae235ec1f510b16d77fe9bfa8f96e
parent36f574135e36b86bb6ae794bf1d0fce3efa5601f
[PATCH] Represent dirty_*_centisecs as jiffies internally

Make that the internal values for:

/proc/sys/vm/dirty_writeback_centisecs
/proc/sys/vm/dirty_expire_centisecs

are stored as jiffies instead of centiseconds.  Let the sysctl interface do
the conversions with full precision using clock_t_to_jiffies, instead of
doing overflow-sensitive on-the-fly conversions every time the values are
used.

Cons: apparent precision loss if HZ is not a multiple of 100, because of
conversion back and forth.  This is a common problem for all sysctl values
that use proc_dointvec_userhz_jiffies.  (There is only one other in-tree
use, in net/core/neighbour.c.)

Signed-off-by: Bart Samwel <bart@samwel.tk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
include/linux/writeback.h
kernel/sysctl.c
mm/page-writeback.c