[PATCH v6 00/21] arch_topology: Updates to add socket support and fix cluster ids

Sudeep Holla sudeep.holla at arm.com
Mon Jul 4 08:20:08 PDT 2022


On Mon, Jul 04, 2022 at 03:10:30PM +0000, Conor.Dooley at microchip.com wrote:
> On 04/07/2022 11:15, Sudeep Holla wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> > 
> > Hi Greg,
> > 
> > Let me know if you prefer to pull the patches directly or prefer pull
> > request. It has been in -next for a while now.
> > 
> > Hi All,
> > 
> > This version updates cacheinfo to populate and use the information from
> > there for all the cache topology.
> > 
> > This series intends to fix some discrepancies we have in the CPU topology
> > parsing from the device tree /cpu-map node. Also this diverges from the
> > behaviour on a ACPI enabled platform. The expectation is that both DT
> > and ACPI enabled systems must present consistent view of the CPU topology.
> > 
> > Currently we assign generated cluster count as the physical package identifier
> > for each CPU which is wrong. The device tree bindings for CPU topology supports
> > sockets to infer the socket or physical package identifier for a given CPU.
> > Also we don't check if all the cores/threads belong to the same cluster before
> > updating their sibling masks which is fine as we don't set the cluster id yet.
> > 
> > These changes also assigns the cluster identifier as parsed from the device tree
> > cluster nodes within /cpu-map without support for nesting of the clusters.
> > Finally, it also add support for socket nodes in /cpu-map. With this the
> > parsing of exact same information from ACPI PPTT and /cpu-map DT node
> > aligns well.
> > 
> > The only exception is that the last level cache id information can be
> > inferred from the same ACPI PPTT while we need to parse CPU cache nodes
> > in the device tree.
> 
> For DT + RISC-V on PolarFire SoC and SiFive fu540
> Tested-by: Conor Dooley <conor.dooley at microchip.com>
> 
> Anecdotally, v5 was tested on the !SMP D1 which worked fine when
> CONFIG_SMP was enabled.
> 

Thanks a lot for testing on RISC-V, much appreciated! Thanks for your
patience and help with v5 so that we could figure out the silly issue
finally.

-- 
Regards,
Sudeep



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