Hi Jan, > -----Original Message----- > From: Jan Beulich <[email protected]> > Sent: 2022年9月29日 20:21 > To: Wei Chen <[email protected]> > Cc: nd <[email protected]>; Andrew Cooper <[email protected]>; Roger Pau > Monné <[email protected]>; Wei Liu <[email protected]>; George Dunlap > <[email protected]>; Julien Grall <[email protected]>; Stefano > Stabellini <[email protected]>; [email protected] > Subject: Re: [PATCH v5 5/6] xen/x86: move NUMA scan nodes codes from x86 > to common > > On 29.09.2022 10:21, Wei Chen wrote: > > On 2022/9/27 23:48, Jan Beulich wrote: > >> On 20.09.2022 11:12, Wei Chen wrote: > >>> --- a/xen/drivers/acpi/Kconfig > >>> +++ b/xen/drivers/acpi/Kconfig > >>> @@ -7,4 +7,5 @@ config ACPI_LEGACY_TABLES_LOOKUP > >>> > >>> config ACPI_NUMA > >>> bool > >>> + select HAS_NUMA_NODE_FWID > >>> select NUMA > >> > >> While I might guess that you've chosen the insertion point to have > >> things sorted alphabetically, I think here it would be more natural > >> to select the wider option first and then also select the more > >> narrow one. > >> > > > > Ok, I will adjust the order. > > > >> One further question though: How is this going to work for Arm64 > >> once it wants to support both the form of NUMA you're working to > >> enable _and_ ACPI-based NUMA? There better wouldn't be a requirement > >> to pick one of the two at build time - it would be nice for support > >> of both forms to be able to co-exist in a single binary. > > > > We are also working in this way. In part#3, we will check ACPI first, > > only when ACPI is off, the DT NUMA will be used by Arm. If ACPI is on, > > we will skip DT NUMA. > > Even more so an answer to my question would be nice: You'll then have > CONFIG_HAS_NUMA_NODE_FWID=y even on Arm (using PXM as mandated by ACPI > when in ACPI mode). But then what's the FWID for DT? I know it was me > to suggest this build time distinction, but I'm afraid I wasn't doing > much good with that (and I'm sorry).
How about introducing a flag for selected NUMA implementation to set it in runtime? For example: bool numa_has_fw_nodeid; ACPI NUMA will set this flag to 1, but 0 for DT NUMA. Cheers, Wei Chen > > Jan
