PARTIAL TAKE 899288 - Rework linux-xfs to use per-cpu vars for xfsstats.

[Eric Sandeen <sandeen@xxxxxxxxxxxxxxxxxxxxxx>]

Re-work pagebuf & xfs stats to use per-cpu variables - 
big globals that are written all the time


Date:  Fri Sep 26 10:49:45 PDT 2003
Workarea:  stout.americas.sgi.com:/localhome/src/sandeen/2.5.x-xfs/workarea

The following file(s) were checked into:
  bonnie.engr.sgi.com:/isms/slinx/2.5.x-xfs


Modid:  2.5.x-xfs:slinx:159069a
linux/fs/xfs/linux/xfs_stats.c - 1.15
linux/fs/xfs/linux/xfs_stats.h - 1.9
linux/fs/xfs/linux/xfs_sysctl.c - 1.23
linux/fs/xfs/pagebuf/page_buf.c - 1.124
linux/fs/xfs/pagebuf/page_buf_internal.h - 1.27