diff options
| author | Ingo Molnar <mingo@elte.hu> | 2007-07-16 09:46:31 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2007-07-16 09:46:31 +0200 |
| commit | 5714d2de93fbb156c5e45fb101a2b4f0cae8fbb7 (patch) | |
| tree | 50f6958246a6247e77816770989cb638c2ff99f1 /kernel | |
| parent | f9153ee6c71cb9ab38de3b8ed66b1c3fa27c3f7d (diff) | |
| download | kernel_samsung_smdk4412-5714d2de93fbb156c5e45fb101a2b4f0cae8fbb7.zip kernel_samsung_smdk4412-5714d2de93fbb156c5e45fb101a2b4f0cae8fbb7.tar.gz kernel_samsung_smdk4412-5714d2de93fbb156c5e45fb101a2b4f0cae8fbb7.tar.bz2 | |
[PATCH] sched: document prio_to_wmult[]
document prio_to_wmult[].
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index a7284bc..90d22b7 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -748,6 +748,13 @@ static const int prio_to_weight[40] = { /* 10 */ 110, 87, 70, 56, 45, 36, 29, 23, 18, 15, }; +/* + * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated. + * + * In cases where the weight does not change often, we can use the + * precalculated inverse to speed up arithmetics by turning divisions + * into multiplications: + */ static const u32 prio_to_wmult[40] = { 48356, 60446, 75558, 94446, 118058, 147573, 184467, 230589, 288233, 360285, 450347, |