Hi Atish,
Thanks for the comments
On 10/10/2017 08:54 AM, Atish Patra wrote:
<snip>
Signed-off-by: Rohit Jain <rohit.k.j...@oracle.com>
---
kernel/sched/fair.c | 37 ++++++++++++++++++++++++++++---------
1 file changed, 28 insertions(+), 9 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index eaede50..5b1f7b9 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6004,7 +6004,7 @@ static int select_idle_core(struct task_struct
*p, struct sched_domain *sd, int
for_each_cpu(cpu, cpu_smt_mask(core)) {
cpumask_clear_cpu(cpu, cpus);
- if (!idle_cpu(cpu))
+ if (!idle_cpu(cpu) || !full_capacity(cpu))
Do we need to skip the entire core just because 1st cpu in the core
doesn't have full capacity ?
Let's say that is the only idle core available. It will go and try to
select_idle_cpu() to find the idlest cpu.
Is it worth spending extra time to search an idle cpu with full
capacity when there are idle cores available ?
This has been previously discussed:
https://lkml.org/lkml/2017/10/3/1001
Returning the best CPU within the idle core did not result in a
statistically significant performance benefit, hence I went with Joel's
suggestion to keep the code simple.
Thanks,
Rohit
<snip>
