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authorTommaso Cucinotta <tommaso.cucinotta@sssup.it>2016-08-14 17:27:06 +0300
committerIngo Molnar <mingo@kernel.org>2016-09-05 14:29:42 +0300
commit126b3b6842cc848fc9880e7816e0a8d743be51f1 (patch)
treee5b1366af338afac534f8392fa77330067aebb46 /kernel
parent97a7142f157a6361a659ff3eec2c3cf636bd7490 (diff)
downloadlinux-126b3b6842cc848fc9880e7816e0a8d743be51f1.tar.xz
sched/deadline: Refactor CPU heap code
1. heapify up factored out in new dedicated function heapify_up() (avoids repetition of same code) 2. call to cpudl_change_key() replaced with heapify_up() when cpudl_set actually inserts a new node in the heap 3. cpudl_change_key() replaced with heapify() that heapifies up or down as needed. Signed-off-by: Tommaso Cucinotta <tommaso.cucinotta@sssup.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Luca Abeni <luca.abeni@unitn.it> Reviewed-by: Juri Lelli <juri.lelli@arm.com> Cc: Juri Lelli <juri.lelli@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-dl@retis.sssup.it Link: http://lkml.kernel.org/r/1471184828-12644-2-git-send-email-tommaso.cucinotta@sssup.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sched/cpudeadline.c50
1 files changed, 23 insertions, 27 deletions
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index d4184498c9f5..0acb0d4e2fb7 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -41,7 +41,7 @@ static void cpudl_exchange(struct cpudl *cp, int a, int b)
swap(cp->elements[cpu_a].idx, cp->elements[cpu_b].idx);
}
-static void cpudl_heapify(struct cpudl *cp, int idx)
+static void cpudl_heapify_down(struct cpudl *cp, int idx)
{
int l, r, largest;
@@ -66,23 +66,24 @@ static void cpudl_heapify(struct cpudl *cp, int idx)
}
}
-static void cpudl_change_key(struct cpudl *cp, int idx, u64 new_dl)
+static void cpudl_heapify_up(struct cpudl *cp, int idx)
{
- WARN_ON(idx == IDX_INVALID || !cpu_present(idx));
-
- if (dl_time_before(new_dl, cp->elements[idx].dl)) {
- cp->elements[idx].dl = new_dl;
- cpudl_heapify(cp, idx);
- } else {
- cp->elements[idx].dl = new_dl;
- while (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl,
- cp->elements[idx].dl)) {
- cpudl_exchange(cp, idx, parent(idx));
- idx = parent(idx);
- }
+ while (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl,
+ cp->elements[idx].dl)) {
+ cpudl_exchange(cp, idx, parent(idx));
+ idx = parent(idx);
}
}
+static void cpudl_heapify(struct cpudl *cp, int idx)
+{
+ if (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl,
+ cp->elements[idx].dl))
+ cpudl_heapify_up(cp, idx);
+ else
+ cpudl_heapify_down(cp, idx);
+}
+
static inline int cpudl_maximum(struct cpudl *cp)
{
return cp->elements[0].cpu;
@@ -154,27 +155,22 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
cp->size--;
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)) {
- cpudl_exchange(cp, old_idx, parent(old_idx));
- old_idx = parent(old_idx);
- }
+ cpudl_heapify(cp, old_idx);
cpumask_set_cpu(cpu, cp->free_cpus);
- cpudl_heapify(cp, old_idx);
goto out;
}
if (old_idx == IDX_INVALID) {
- cp->size++;
- cp->elements[cp->size - 1].dl = dl;
- cp->elements[cp->size - 1].cpu = cpu;
- cp->elements[cpu].idx = cp->size - 1;
- cpudl_change_key(cp, cp->size - 1, dl);
+ int new_idx = cp->size++;
+ cp->elements[new_idx].dl = dl;
+ cp->elements[new_idx].cpu = cpu;
+ cp->elements[cpu].idx = new_idx;
+ cpudl_heapify_up(cp, new_idx);
cpumask_clear_cpu(cpu, cp->free_cpus);
} else {
- cpudl_change_key(cp, old_idx, dl);
+ cp->elements[old_idx].dl = dl;
+ cpudl_heapify(cp, old_idx);
}
out: