Re: [PATCH v2] arch_topology: Introduce nr_possible_packages

Sudeep Holla <[email protected]> Tue, 21 Jul 2026 15:32:03 +0100
Newsgroups dev.linux.lists.driver-core,org.kernel.vger.linux-kernel
Message-ID <20260721-armored-lion-of-pluck-9fc8a0@sudeepholla>
On Tue, Jul 14, 2026 at 01:43:17PM +0800, Feng Tang wrote:
> For multi-sockets platforms kernel or driver code may need the number
> of packages to chose different code directions. Some architecture
> already provides such kind of interface like x86, which is being used
> in its architecture code and drivers.
> 
> Add similar interface 'nr_possible_packages' for platforms which can
> get package topology information by parsing ACPI tables in boot phase,
> which was verified to show the correct number of packages on some
> 1-socket and 2-sockets production arm64 servers from different vendors.
> 
> It has been used locally by some arm64 PMU driver, and cross-socket
> timer-consistency check code, which are to be posted.
> 
> Signed-off-by: Feng Tang <[email protected]>
> ---
>   since v1:
>       * fix the potential overflow issue for 32b package ID (Sudeep)
> 	  * add real use case in commit log (Sudeep)
> 
>   since RFC:
>       * use EXPORT_SYMBOL_GPL instead of EXPORT_SYMBOL (Greg)

This is undone in this version, why ?

> 	  * change the possible max package ID to 2047 (Greg)
> 	  * remove the CONFIG_ARM64/RISCV limit for 'nr_possible_packages' (Greg)

Again this is still there, misleading or v2 is back to RFC, /me confused.

> 
>   v1:  https://lore.kernel.org/lkml/[email protected]/ 

Comments about users is still ignored.

-- 
Regards,
Sudeep

P.S.: Please avoid personal pings as it will not gain attention from other
interested parties.