[PATCH v2 4/7] sched: powerpc: create a dedicated topology table

[Preeti U Murthy]

On 03/18/2014 11:26 PM, Vincent Guittot wrote:
> Create a dedicated topology table for handling asymetric feature of powerpc.
> 
> Signed-off-by: Vincent Guittot <vincent.guittot at linaro.org>
> ---
>  arch/powerpc/kernel/smp.c | 31 +++++++++++++++++++++++--------
>  include/linux/sched.h     |  2 --
>  kernel/sched/core.c       |  6 ------
>  3 files changed, 23 insertions(+), 16 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
> index ac2621a..c9cade5 100644
> --- a/arch/powerpc/kernel/smp.c
> +++ b/arch/powerpc/kernel/smp.c
> @@ -755,6 +755,28 @@ int setup_profiling_timer(unsigned int multiplier)
>  	return 0;
>  }
> 
> +#ifdef CONFIG_SCHED_SMT
> +/* cpumask of CPUs with asymetric SMT dependancy */
> +static const int powerpc_smt_flags(void)
> +{
> +	int flags = SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES;
> +
> +	if (cpu_has_feature(CPU_FTR_ASYM_SMT)) {
> +		printk_once(KERN_INFO "Enabling Asymmetric SMT scheduling\n");
> +		flags |= SD_ASYM_PACKING;
> +	}
> +	return flags;
> +}
> +#endif
> +
> +static struct sched_domain_topology_level powerpc_topology[] = {
> +#ifdef CONFIG_SCHED_SMT
> +	{ cpu_smt_mask, powerpc_smt_flags, SD_INIT_NAME(SMT) },
> +#endif
> +	{ cpu_cpu_mask, SD_INIT_NAME(DIE) },
> +	{ NULL, },
> +};
> +
>  void __init smp_cpus_done(unsigned int max_cpus)
>  {
>  	cpumask_var_t old_mask;
> @@ -779,15 +801,8 @@ void __init smp_cpus_done(unsigned int max_cpus)
> 
>  	dump_numa_cpu_topology();
> 
> -}
> +	set_sched_topology(powerpc_topology);
> 
> -int arch_sd_sibling_asym_packing(void)
> -{
> -	if (cpu_has_feature(CPU_FTR_ASYM_SMT)) {
> -		printk_once(KERN_INFO "Enabling Asymmetric SMT scheduling\n");
> -		return SD_ASYM_PACKING;
> -	}
> -	return 0;
>  }
> 
>  #ifdef CONFIG_HOTPLUG_CPU
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index 4db592a..6479de4 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -868,8 +868,6 @@ enum cpu_idle_type {
>  #define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
>  #define SD_NUMA			0x4000	/* cross-node balancing */
> 
> -extern int __weak arch_sd_sibiling_asym_packing(void);
> -
>  #ifdef CONFIG_SCHED_SMT
>  static inline const int cpu_smt_flags(void)
>  {
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index f2bfa76..0b51ee3 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -5833,11 +5833,6 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
>  	atomic_set(&sg->sgp->nr_busy_cpus, sg->group_weight);
>  }
> 
> -int __weak arch_sd_sibling_asym_packing(void)
> -{
> -       return 0*SD_ASYM_PACKING;
> -}
> -
>  /*
>   * Initializers for schedule domains
>   * Non-inlined to reduce accumulated stack pressure in build_sched_domains()
> @@ -6018,7 +6013,6 @@ sd_init(struct sched_domain_topology_level *tl, int cpu)
>  	if (sd->flags & SD_SHARE_CPUPOWER) {
>  		sd->imbalance_pct = 110;
>  		sd->smt_gain = 1178; /* ~15% */
> -		sd->flags |= arch_sd_sibling_asym_packing();
> 
>  	} else if (sd->flags & SD_SHARE_PKG_RESOURCES) {
>  		sd->imbalance_pct = 117;
> 
Reviewed-by: Preeti U Murthy <preeti at linux.vnet.ibm.com>