Cédric Le Goater <c...@kaod.org> writes: > The 'chip_id' field of the XIVE CPU structure is used to choose a > target for a source located on the same chip when possible. This field > is assigned on the PowerNV platform using the "ibm,chip-id" property > on pSeries under KVM when NUMA nodes are defined but it is undefined > under PowerVM. The XIVE source structure has a similar field > 'src_chip' which is only assigned on the PowerNV platform. > > cpu_to_node() returns a compatible value on all platforms, 0 being the > default node. It will also give us the opportunity to set the affinity > of a source on pSeries when we can localize them.
But we should avoid assuming that linux numa node number is equivalent to chip id [1]. What do we expect this value represents on virtualized platforms like PowerVM and KVM? Is this used for a hcall? [1] https://lore.kernel.org/linuxppc-dev/20200817103238.158133-1-aneesh.ku...@linux.ibm.com > > Signed-off-by: Cédric Le Goater <c...@kaod.org> > --- > arch/powerpc/sysdev/xive/common.c | 7 +------ > 1 file changed, 1 insertion(+), 6 deletions(-) > > diff --git a/arch/powerpc/sysdev/xive/common.c > b/arch/powerpc/sysdev/xive/common.c > index ee375daf8114..605238ca65e4 100644 > --- a/arch/powerpc/sysdev/xive/common.c > +++ b/arch/powerpc/sysdev/xive/common.c > @@ -1342,16 +1342,11 @@ static int xive_prepare_cpu(unsigned int cpu) > > xc = per_cpu(xive_cpu, cpu); > if (!xc) { > - struct device_node *np; > - > xc = kzalloc_node(sizeof(struct xive_cpu), > GFP_KERNEL, cpu_to_node(cpu)); > if (!xc) > return -ENOMEM; > - np = of_get_cpu_node(cpu, NULL); > - if (np) > - xc->chip_id = of_get_ibm_chip_id(np); > - of_node_put(np); > + xc->chip_id = cpu_to_node(cpu); > xc->hw_ipi = XIVE_BAD_IRQ; > > per_cpu(xive_cpu, cpu) = xc; > -- > 2.26.2
