lkml.org 
[lkml]   [2017]   [May]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH RFC 7/8] sched/sched.h: move arch_scale_{freq,cpu}_capacity outside CONFIG_SMP
    Date
    Currently, frequency and cpu capacity scaling is only performed on
    CONFIG_SMP system (as CFS PELT signals are only present for such systems
    as well). However, other scheduling class want to do freq/cpu scaling as
    well, and for !CONFIG_SMP configurations too.

    arch_scale_freq_capacity is useful to implement frequency scaling even
    on !CONFIG_SMP platforms, so we simply move it outside CONFIG_SMP
    ifdeffery.

    Even if arch_scale_cpu_capacity is not useful on !CONFIG_SMP platforms,
    we make a default implementation available for such configurations anyway
    to simplify scheduler code doing CPU scale invariance.

    Signed-off-by: Juri Lelli <juri.lelli@arm.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Ingo Molnar <mingo@kernel.org>
    ---
    include/linux/sched/topology.h | 12 ++++++------
    kernel/sched/sched.h | 13 ++++++++++---
    2 files changed, 16 insertions(+), 9 deletions(-)

    diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
    index 7d065abc7a47..953cf4f889ec 100644
    --- a/include/linux/sched/topology.h
    +++ b/include/linux/sched/topology.h
    @@ -6,6 +6,12 @@
    #include <linux/sched/idle.h>

    /*
    + * Increase resolution of cpu_capacity calculations
    + */
    +#define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
    +#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
    +
    +/*
    * sched-domains (multiprocessor balancing) declarations:
    */
    #ifdef CONFIG_SMP
    @@ -26,12 +32,6 @@
    #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */
    #define SD_NUMA 0x4000 /* cross-node balancing */

    -/*
    - * Increase resolution of cpu_capacity calculations
    - */
    -#define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
    -#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
    -
    #ifdef CONFIG_SCHED_SMT
    static inline int cpu_smt_flags(void)
    {
    diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
    index 063fd8c47e75..cc474c62cd18 100644
    --- a/kernel/sched/sched.h
    +++ b/kernel/sched/sched.h
    @@ -1636,9 +1636,6 @@ static inline int hrtick_enabled(struct rq *rq)

    #endif /* CONFIG_SCHED_HRTICK */

    -#ifdef CONFIG_SMP
    -extern void sched_avg_update(struct rq *rq);
    -
    #ifndef arch_scale_freq_capacity
    static __always_inline
    unsigned long arch_scale_freq_capacity(int cpu)
    @@ -1647,6 +1644,9 @@ unsigned long arch_scale_freq_capacity(int cpu)
    }
    #endif

    +#ifdef CONFIG_SMP
    +extern void sched_avg_update(struct rq *rq);
    +
    #ifndef arch_scale_cpu_capacity
    static __always_inline
    unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
    @@ -1664,6 +1664,13 @@ static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
    sched_avg_update(rq);
    }
    #else
    +#ifndef arch_scale_cpu_capacity
    +static __always_inline
    +unsigned long arch_scale_cpu_capacity(void __always_unused *sd, int cpu)
    +{
    + return SCHED_CAPACITY_SCALE;
    +}
    +#endif
    static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
    static inline void sched_avg_update(struct rq *rq) { }
    #endif
    --
    2.11.0
    \
     
     \ /
      Last update: 2017-05-23 10:57    [W:4.404 / U:0.004 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site