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

From: Preeti U Murthy
Date: Wed Mar 19 2014 - 02:08:38 EST


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@xxxxxxxxxx>
> ---
> 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@xxxxxxxxxxxxxxxxxx>

--
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/