Re: [PATCH 3/3] ppc64: Convert cpu_sibling_map to a per_cpu data array

[Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>]

Kamalesh Babulal wrote:
> travis@sgi.com wrote:
>> Convert cpu_sibling_map to a per_cpu cpumask_t array for the ppc64
>> architecture.
>>
>> Note: these changes have not been built nor tested.
>>
>> Note: I also don't know if these changes are particularly
>> relevant for the ppc64 architecture.
>>
>> Signed-off-by: Mike Travis <travis@sgi.com>
>> ---
>>  arch/powerpc/kernel/setup-common.c        |    4 ++--
>>  arch/powerpc/kernel/smp.c                 |    4 ++--
>>  arch/powerpc/platforms/cell/cbe_cpufreq.c |    2 +-
>>  include/asm-powerpc/smp.h                 |    3 ++-
>>  include/asm-powerpc/topology.h            |    2 +-
>>  5 files changed, 8 insertions(+), 7 deletions(-)
>>
>> --- a/arch/powerpc/kernel/setup-common.c
>> +++ b/arch/powerpc/kernel/setup-common.c
>> @@ -415,9 +415,9 @@
>>       * Do the sibling map; assume only two threads per processor.
>>       */
>>      for_each_possible_cpu(cpu) {
>> -        cpu_set(cpu, cpu_sibling_map[cpu]);
>> +        cpu_set(cpu, cpu_sibling_map(cpu));
>>          if (cpu_has_feature(CPU_FTR_SMT))
>> -            cpu_set(cpu ^ 0x1, cpu_sibling_map[cpu]);
>> +            cpu_set(cpu ^ 0x1, cpu_sibling_map(cpu));
>>      }
>>
>>      vdso_data->processorCount = num_present_cpus();
>> --- a/arch/powerpc/kernel/smp.c
>> +++ b/arch/powerpc/kernel/smp.c
>> @@ -61,11 +61,11 @@
>>
>>  cpumask_t cpu_possible_map = CPU_MASK_NONE;
>>  cpumask_t cpu_online_map = CPU_MASK_NONE;
>> -cpumask_t cpu_sibling_map[NR_CPUS] = { [0 ... NR_CPUS-1] = 
>> CPU_MASK_NONE };
>> +DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
>>
>>  EXPORT_SYMBOL(cpu_online_map);
>>  EXPORT_SYMBOL(cpu_possible_map);
>> -EXPORT_SYMBOL(cpu_sibling_map);
>> +EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
>>
>>  /* SMP operations for this machine */
>>  struct smp_ops_t *smp_ops;
>> --- a/arch/powerpc/platforms/cell/cbe_cpufreq.c
>> +++ b/arch/powerpc/platforms/cell/cbe_cpufreq.c
>> @@ -117,7 +117,7 @@
>>      policy->cur = cbe_freqs[cur_pmode].frequency;
>>
>>  #ifdef CONFIG_SMP
>> -    policy->cpus = cpu_sibling_map[policy->cpu];
>> +    policy->cpus = cpu_sibling_map(policy->cpu);
>>  #endif
>>
>>      cpufreq_frequency_table_get_attr(cbe_freqs, policy->cpu);
>> --- a/include/asm-powerpc/smp.h
>> +++ b/include/asm-powerpc/smp.h
>> @@ -58,7 +58,8 @@
>>                      (smp_hw_index[(cpu)] = (phys))
>>  #endif
>>
>> -extern cpumask_t cpu_sibling_map[NR_CPUS];
>> +DECLARE_PER_CPU(cpumask_t, cpu_sibling_map);
>> +#define cpu_sibling_map(cpu) per_cpu(cpu_sibling_map, cpu)
>>
>>  /* Since OpenPIC has only 4 IPIs, we use slightly different message 
>> numbers.
>>   *
>> --- a/include/asm-powerpc/topology.h
>> +++ b/include/asm-powerpc/topology.h
>> @@ -108,7 +108,7 @@
>>  #ifdef CONFIG_PPC64
>>  #include <asm/smp.h>
>>
>> -#define topology_thread_siblings(cpu)    (cpu_sibling_map[cpu])
>> +#define topology_thread_siblings(cpu)    (cpu_sibling_map(cpu))
>>  #endif
>>  #endif
>>
>>
>>   
> Hi Mike,
>
> After applying the patch, the build fails with following error
>
> CHK include/linux/version.h
> CHK include/linux/utsrelease.h
> CC arch/powerpc/kernel/asm-offsets.s
> In file included from include/linux/smp.h:19,
> from include/linux/topology.h:33,
> from include/linux/mmzone.h:660,
> from include/linux/gfp.h:4,
> from include/linux/slab.h:14,
> from include/linux/percpu.h:5,
> from include/asm/time.h:18,
> from include/asm/cputime.h:26,
> from include/linux/sched.h:65,
> from arch/powerpc/kernel/asm-offsets.c:17:
> include/asm/smp.h:61: error: expected declaration specifiers or ‘...’ 
> before ‘cpu_sibling_map’
> include/asm/smp.h:61: warning: data definition has no type or storage 
> class
> include/asm/smp.h:61: warning: type defaults to ‘int’ in declaration 
> of ‘DECLARE_PER_CPU’
> make[1]: *** [arch/powerpc/kernel/asm-offsets.s] Error 1
> make: *** [prepare0] Error 2
>
> Thanks & Regards,
> Kamalesh Babulal.
Hi Make,

I tried to debug and probably the patch below could help the build error

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
----

--- a/include/asm-powerpc/smp.h 2007-09-07 18:15:43.000000000 +0530
+++ b/include/asm-powerpc/smp.h 2007-09-07 18:16:02.000000000 +0530
@@ -25,6 +25,7 @@
 
 #ifdef CONFIG_PPC64
 #include <asm/paca.h>
+#include <asm/percpu.h>
 #endif
 
 extern int boot_cpuid;

---
Thanks & Regards,
Kamalesh Babulal.