diff options
| author | avg <avg@FreeBSD.org> | 2011-12-19 20:01:21 +0000 |
|---|---|---|
| committer | avg <avg@FreeBSD.org> | 2011-12-19 20:01:21 +0000 |
| commit | 8d78bfbee05852f5ebc3b662b38339d054324ce7 (patch) | |
| tree | 269b9f5473eec33ab31a455b4b12db8353b2dc5d | |
| parent | 291f526f0d0040a4222df61b67512e26e082864a (diff) | |
| download | FreeBSD-src-8d78bfbee05852f5ebc3b662b38339d054324ce7.zip FreeBSD-src-8d78bfbee05852f5ebc3b662b38339d054324ce7.tar.gz | |
ule: ensure that batch timeshare threads are scheduled fairly
With the previous code, if the range of priorities for timeshare batch
threads was greater than RQ_NQS, then the threads with low priorities in
the part of the range above RQ_NQS would be scheduled to the run-queues
as if they had high priorities at the beginning of the range.
In other words, threads with a nice level of +N could be scheduled as
if they had a nice level of -M.
Reported by: George Mitchell <george@m5p.com>
Reviewed by: jhb
Tested by: George Mitchell <george@m5p.com> (earlier version)
MFC after: 1 week
| -rw-r--r-- | sys/kern/sched_ule.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sys/kern/sched_ule.c b/sys/kern/sched_ule.c index 31d3d11..1d34342 100644 --- a/sys/kern/sched_ule.c +++ b/sys/kern/sched_ule.c @@ -125,6 +125,7 @@ static struct td_sched td_sched0; */ #define PRI_TIMESHARE_RANGE (PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE + 1) #define PRI_INTERACT_RANGE ((PRI_TIMESHARE_RANGE - SCHED_PRI_NRESV) / 2) +#define PRI_BATCH_RANGE (PRI_TIMESHARE_RANGE - PRI_INTERACT_RANGE) #define PRI_MIN_INTERACT PRI_MIN_TIMESHARE #define PRI_MAX_INTERACT (PRI_MIN_TIMESHARE + PRI_INTERACT_RANGE - 1) @@ -416,7 +417,6 @@ sched_shouldpreempt(int pri, int cpri, int remote) return (0); } -#define TS_RQ_PPQ (((PRI_MAX_BATCH - PRI_MIN_BATCH) + 1) / RQ_NQS) /* * Add a thread to the actual run-queue. Keeps transferable counts up to * date with what is actually on the run-queue. Selects the correct @@ -449,7 +449,7 @@ tdq_runq_add(struct tdq *tdq, struct thread *td, int flags) * realtime. Use the whole queue to represent these values. */ if ((flags & (SRQ_BORROWING|SRQ_PREEMPTED)) == 0) { - pri = (pri - PRI_MIN_BATCH) / TS_RQ_PPQ; + pri = RQ_NQS * (pri - PRI_MIN_BATCH) / PRI_BATCH_RANGE; pri = (pri + tdq->tdq_idx) % RQ_NQS; /* * This effectively shortens the queue by one so we |
