On Fri, 16 May 2014 12:43:36 +0200
Peter Zijlstra <pet...@infradead.org> wrote:

> 
> OK I made that..
> 

Are the comments I proposed to add overdoing?

Apart from this,

Acked-by: Juri Lelli <juri.le...@gmail.com>

Thanks!

- Juri

> ---
> 
> Subject: sched/cpudl: Replace NR_CPUS arrays
> From: Peter Zijlstra <pet...@infradead.org>
> Date: Wed May 14 16:13:56 CEST 2014
> 
> Tejun reported that his resume was failing due to order-3 allocations
> from sched_domain building.
> 
> Replace the NR_CPUS arrays in there with a dynamically allocated
> array.
> 
> Cc: Johannes Weiner <han...@cmpxchg.org>
> Cc: Juri Lelli <juri.le...@gmail.com>
> Reported-by: Tejun Heo <t...@kernel.org>
> Signed-off-by: Peter Zijlstra <pet...@infradead.org>
> ---
>  kernel/sched/cpudeadline.c |   33 ++++++++++++++++++++++++---------
>  kernel/sched/cpudeadline.h |    6 +++---
>  2 files changed, 27 insertions(+), 12 deletions(-)
> 
> --- a/kernel/sched/cpudeadline.c
> +++ b/kernel/sched/cpudeadline.c
> @@ -13,6 +13,7 @@
>  
>  #include <linux/gfp.h>
>  #include <linux/kernel.h>
> +#include <linux/slab.h>
>  #include "cpudeadline.h"
>  
>  static inline int parent(int i)
> @@ -39,8 +40,10 @@ static void cpudl_exchange(struct cpudl
>  {
>       int cpu_a = cp->elements[a].cpu, cpu_b = cp->elements[b].cpu;
>  
> -     swap(cp->elements[a], cp->elements[b]);
> -     swap(cp->cpu_to_idx[cpu_a], cp->cpu_to_idx[cpu_b]);
> +     swap(cp->elements[a].cpu, cp->elements[b].cpu);
> +     swap(cp->elements[a].dl , cp->elements[b].dl );
> +
> +     swap(cp->elements[cpu_a].idx, cp->elements[cpu_b].idx);
>  }
>  
>  static void cpudl_heapify(struct cpudl *cp, int idx)
> @@ -140,7 +143,7 @@ void cpudl_set(struct cpudl *cp, int cpu
>       WARN_ON(!cpu_present(cpu));
>  
>       raw_spin_lock_irqsave(&cp->lock, flags);
> -     old_idx = cp->cpu_to_idx[cpu];
> +     old_idx = cp->elements[cpu].idx;
>       if (!is_valid) {
>               /* remove item */
>               if (old_idx == IDX_INVALID) {
> @@ -155,8 +158,8 @@ void cpudl_set(struct cpudl *cp, int cpu
>               cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl;
>               cp->elements[old_idx].cpu = new_cpu;
>               cp->size--;
> -             cp->cpu_to_idx[new_cpu] = old_idx;
> -             cp->cpu_to_idx[cpu] = IDX_INVALID;
> +             cp->elements[new_cpu].idx = old_idx;
> +             cp->elements[cpu].idx = IDX_INVALID;
>               while (old_idx > 0 && dl_time_before(
>                               cp->elements[parent(old_idx)].dl,
>                               cp->elements[old_idx].dl)) {
> @@ -173,7 +176,7 @@ void cpudl_set(struct cpudl *cp, int cpu
>               cp->size++;
>               cp->elements[cp->size - 1].dl = 0;
>               cp->elements[cp->size - 1].cpu = cpu;
> -             cp->cpu_to_idx[cpu] = cp->size - 1;
> +             cp->elements[cpu].idx = cp->size - 1;
>               cpudl_change_key(cp, cp->size - 1, dl);
>               cpumask_clear_cpu(cpu, cp->free_cpus);
>       } else {
> @@ -195,10 +198,21 @@ int cpudl_init(struct cpudl *cp)
>       memset(cp, 0, sizeof(*cp));
>       raw_spin_lock_init(&cp->lock);
>       cp->size = 0;
> -     for (i = 0; i < NR_CPUS; i++)
> -             cp->cpu_to_idx[i] = IDX_INVALID;
> -     if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL))
> +
> +     cp->elements = kcalloc(nr_cpu_ids,
> +                            sizeof(struct cpudl_item),
> +                            GFP_KERNEL);
> +     if (!cp->elements)
> +             return -ENOMEM;
> +
> +     if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) {
> +             kfree(cp->elements);
>               return -ENOMEM;
> +     }
> +
> +     for_each_possible_cpu(i)
> +             cp->elements[i].idx = IDX_INVALID;
> +
>       cpumask_setall(cp->free_cpus);
>  
>       return 0;
> @@ -211,4 +225,5 @@ int cpudl_init(struct cpudl *cp)
>  void cpudl_cleanup(struct cpudl *cp)
>  {
>       free_cpumask_var(cp->free_cpus);
> +     kfree(cp->elements);
>  }
> --- a/kernel/sched/cpudeadline.h
> +++ b/kernel/sched/cpudeadline.h
> @@ -5,17 +5,17 @@
>  
>  #define IDX_INVALID     -1
>  
> -struct array_item {
> +struct cpudl_item {
>       u64 dl;
>       int cpu;
> +     int idx;
>  };
>  
>  struct cpudl {
>       raw_spinlock_t lock;
>       int size;
> -     int cpu_to_idx[NR_CPUS];
> -     struct array_item elements[NR_CPUS];
>       cpumask_var_t free_cpus;
> +     struct cpudl_item *elements;
>  };
>  
>  
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to