Commit e0cd5160 authored Apr 17, 2009 by Andreas Herrmann Committed by Jesse Barnes Nov 06, 2009

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>

parent ea7f1b6e

drivers/pci/pci-sysfs.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -74,7 +74,11 @@ static ssize_t local_cpus_show(struct device *dev,
		const struct cpumask *mask;
		int len;

		#ifdef CONFIG_NUMA
		mask = cpumask_of_node(dev_to_node(dev));
		#else
		mask = cpumask_of_pcibus(to_pci_dev(dev)->bus);
		#endif
		len = cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
		buf[len++] = '\n';
		buf[len] = '\0';
		@@ -88,7 +92,11 @@ static ssize_t local_cpulist_show(struct device *dev,
		const struct cpumask *mask;
		int len;

		#ifdef CONFIG_NUMA
		mask = cpumask_of_node(dev_to_node(dev));
		#else
		mask = cpumask_of_pcibus(to_pci_dev(dev)->bus);
		#endif
		len = cpulist_scnprintf(buf, PAGE_SIZE-2, mask);
		buf[len++] = '\n';
		buf[len] = '\0';

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