lkml.org 
[lkml]   [2014]   [May]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:sched/core] sched/deadline: Replace NR_CPUS arrays
Commit-ID:  944770ab54babaef29d9d1dc8189898b3ee8afcf
Gitweb: http://git.kernel.org/tip/944770ab54babaef29d9d1dc8189898b3ee8afcf
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Wed, 14 May 2014 16:13:56 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 22 May 2014 10:21:28 +0200

sched/deadline: Replace NR_CPUS arrays

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.

Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-kat4gl1m5a6dwy6nzuqox45e@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
kernel/sched/cpudeadline.c | 33 ++++++++++++++++++++++++---------
kernel/sched/cpudeadline.h | 6 +++---
2 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index ab001b5..bd95963 100644
--- 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 *cp, int a, int b)
{
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, u64 dl, int is_valid)
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, u64 dl, int is_valid)
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, u64 dl, int is_valid)
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);
}
diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h
index a202789..538c979 100644
--- 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;
};



\
 
 \ /
  Last update: 2014-05-22 18:21    [W:0.026 / U:0.132 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site