Hi,
On 04/26/2018 05:27 AM, Sudeep Holla wrote:
On 26/04/18 00:31, Jeremy Linton wrote:
Its helpful to be able to lookup the acpi_processor_id associated
with a logical cpu. Provide an arm64 helper to do this.
As I pointed out in the earlier version, this patch is not required.
The acpi_id stored in the acpi_processor can be used for this.
Won't the below change make it work ? I can't think of any reason why it
shouldn't.
So, I only noticed your previous email last night on the mail archive,
as I was applying your review/ack tags and couldn't find a response for
this patch, seem the spam/etc filters need some further tweaking!
At that point, I was pretty sure the suggestion wasn't going to work out
of the box as a lot of this code is running fairly early in the boot
process. I spent a bit of time and plugged the change in to verify that
assertion, and yes the per_cpu processor/acpi bits aren't setup early
enough to be used by much of this code. It is being called from
init_cpu_topology()/smp_prepare_cpus() which precedes
do_basic_setup/do_initcalls() which is what runs the acpi_init()
sequence which ends up eventually allocating the required data
structures. So without restructuring the core boot sequence, this seems
like a reasonable solution.
Thanks,
Regards,
Sudeep
-->8
diff --git i/drivers/acpi/pptt.c w/drivers/acpi/pptt.c
index 0fc4b2654665..f421f58b4ae6 100644
--- i/drivers/acpi/pptt.c
+++ w/drivers/acpi/pptt.c
@@ -432,7 +432,7 @@ static void cache_setup_acpi_cpu(struct
acpi_table_header *table,
{
struct acpi_pptt_cache *found_cache;
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
- u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu);
+ u32 acpi_cpu_id = per_cpu(processors, cpu)->acpi_id;
struct cacheinfo *this_leaf;
unsigned int index = 0;
struct acpi_pptt_processor *cpu_node = NULL;
