Re: [PATCH v4 0/2] Fix how CPUs are enumerated when there's more than 255 CPUs

[Rafael J. Wysocki]

On Wednesday, September 09, 2015 03:47:27 PM Lukasz Anaczkowski wrote:
> This series of patches attempts to fix how CPUs are enumerated by kernel when
> there's more than 255 of them on single processor.
> In such case, BIOS may interleave APIC/X2APIC MADT subtables, to obey requirements
> specified in ACPI spec. Without this patches, kernel then would first enumerate
> BSP, then X2APIC then APIC, resulting in low APIC IDs to be assigned with high
> logical IDs and high APIC IDs to be assigned low logical IDs. Biggest consequence
> of that could be performance penalties due to wrong L2 cache sharing.
> More details in patch 2/2.
> 
> Also, simpler approach has been considered, which did not required ACPI parsing
> interface changes, however it failed to meet requirements. More details can be
> found here: https://lkml.org/lkml/2015/9/7/285
> 
> Lukasz Anaczkowski (2):
>   acpi: Added acpi_subtable_proc to ACPI table parsers
>   x86, acpi: Handle apic/x2apic entries in MADT in correct order
> 
>  arch/x86/kernel/acpi/boot.c | 22 +++++++++--
>  drivers/acpi/tables.c       | 91 ++++++++++++++++++++++++++++++++++++---------
>  include/linux/acpi.h        | 19 ++++++++--
>  3 files changed, 107 insertions(+), 25 deletions(-)

OK

Does anyone in the CC have any objections against merging this series?

If not, I'll queue it up as 4.3-rc material.

Thanks,
Rafael

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/