Function gpuFillNUMANodes

pkg/gpu/gpu_linux.go:134–174

Loops through each GraphicsCard struct and find which NUMA node the card is affined to, setting the GraphicsCard.Node field accordingly. If the host system is not a NUMA system, the Node field will be set to nil.

(ctx context.Context, cards []*GraphicsCard)

// affined to, setting the GraphicsCard.Node field accordingly. If the host
// system is not a NUMA system, the Node field will be set to nil.
func gpuFillNUMANodes(ctx context.Context, cards []*GraphicsCard) {
	paths := linuxpath.New(ctx)
	// Skip topology detection if requested to reduce memory consumption
	if !config.TopologyEnabled(ctx) {
		for _, card := range cards {
			card.Node = nil
		}
		return
	}

	topo, err := topology.New(ctx)
	if err != nil {
		// Problem getting topology information so just set the graphics card's
		// node to nil
		for _, card := range cards {
			card.Node = nil
		}
		return
	}
	for _, card := range cards {
		// Each graphics card on a NUMA system will have a pseudo-file
		// called /sys/class/drm/card$CARD_INDEX/device/numa_node which
		// contains the NUMA node that the card is affined to
		cardIndexStr := strconv.Itoa(card.Index)
		fpath := filepath.Join(
			paths.SysClassDRM,
			"card"+cardIndexStr,
			"device",
			"numa_node",
		)
		nodeIdx := util.SafeIntFromFile(ctx, fpath)
		if nodeIdx == -1 {
			continue
		}
		for _, node := range topo.Nodes {
			if nodeIdx == int(node.ID) {
				card.Node = node
			}
		}
	}
}