PCI: derive nearby CPUs from device's instead of bus' NUMA information
authorAndreas Herrmann <andreas.herrmann3@amd.com>
Fri, 17 Apr 2009 10:01:55 +0000 (12:01 +0200)
committerJesse Barnes <jbarnes@virtuousgeek.org>
Fri, 6 Nov 2009 22:09:15 +0000 (14:09 -0800)
commite0cd5160346f5b88fe536f529066f102518f8acd
treed6c2ffc944c9ee0d4215287d3b416f2e9712dc10
parentea7f1b6ee9dc96c5827b06ba21d7769d553efb7d
PCI: derive nearby CPUs from device's instead of bus' NUMA information

In case of AMD CPU northbridge functions this NUMA information might
differ.  Here is an example from a 4-socket system.

Currently Linux shows

  root@hagen:/sys/devices/pci0000:00/0000:00:1a.4# cat numa_node
  0
  root@hagen:/sys/devices/pci0000:00/0000:00:1a.4# cat local_cpu*
  0-3
  00000000,0000000f

which is not correct for northbridge functions as the local CPUs
are those of the same socket.

With this patch and a quirk for AMD CPU NB functions Linux can
do better and correctly show

  root@hagen:/sys/devices/pci0000:00/0000:00:1a.4# cat numa_node
  2
  root@hagen:/sys/devices/pci0000:00/0000:00:1a.4# cat local_cpu*
  8-11
  00000000,00000f00

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
drivers/pci/pci-sysfs.c