| Message ID | 16324b54-42d4-d9bc-6d57-de52431dc209@arm.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
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; > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 26/04/18 19:33, Jeremy Linton wrote: > 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! > Ah that's bad. > 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. > OK makes sense. I completely ignored topology related patches as I haven't looked at them yet and assumed cacheinfo is the only user. Sorry for that.
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;