2021-08-21 09:06:36

by Yicong Yang

Subject: [PATCH] sched/topology: Remove unused numa_distance in cpu_attach_domain()

numa_distance in cpu_attach_domain() is introduced in
commit b5b217346de8 ("sched/topology: Warn when NUMA diameter > 2")
to warn user when NUMA diameter > 2 as we'll misrepresent
the scheduler topology structures at that time. This is
fixed by Barry in commit 585b6d2723dc ("sched/topology: fix the issue
groups don't span domain->span for NUMA diameter > 2") and
numa_distance is unused now. So remove it.

Signed-off-by: Yicong Yang <[email protected]>
---
kernel/sched/topology.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index b77ad49dc14f..ccbb141df8c8 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -688,7 +688,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
{
struct rq *rq = cpu_rq(cpu);
struct sched_domain *tmp;
- int numa_distance = 0;

/* Remove the sched domains which do not contribute to scheduling. */
for (tmp = sd; tmp; ) {
@@ -720,9 +719,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
sd->child = NULL;
}

- for (tmp = sd; tmp; tmp = tmp->parent)
- numa_distance += !!(tmp->flags & SD_NUMA);
-
sched_domain_debug(sd, cpu);

rq_attach_root(rq, rd);
--
2.17.1

2021-08-21 22:01:35

by Barry Song

Subject: Re: [PATCH] sched/topology: Remove unused numa_distance in cpu_attach_domain()

On Sat, Aug 21, 2021 at 9:04 PM Yicong Yang <[email protected]> wrote:
>
> numa_distance in cpu_attach_domain() is introduced in
> commit b5b217346de8 ("sched/topology: Warn when NUMA diameter > 2")
> to warn user when NUMA diameter > 2 as we'll misrepresent
> the scheduler topology structures at that time. This is
> fixed by Barry in commit 585b6d2723dc ("sched/topology: fix the issue
> groups don't span domain->span for NUMA diameter > 2") and
> numa_distance is unused now. So remove it.
>
> Signed-off-by: Yicong Yang <[email protected]>

looks good to me.

> ---
> kernel/sched/topology.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
> index b77ad49dc14f..ccbb141df8c8 100644
> --- a/kernel/sched/topology.c
> +++ b/kernel/sched/topology.c
> @@ -688,7 +688,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
> {
> struct rq *rq = cpu_rq(cpu);
> struct sched_domain *tmp;
> - int numa_distance = 0;
>
> /* Remove the sched domains which do not contribute to scheduling. */
> for (tmp = sd; tmp; ) {
> @@ -720,9 +719,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
> sd->child = NULL;
> }
>
> - for (tmp = sd; tmp; tmp = tmp->parent)
> - numa_distance += !!(tmp->flags & SD_NUMA);
> -
> sched_domain_debug(sd, cpu);
>
> rq_attach_root(rq, rd);
> --
> 2.17.1
>

Thanks
Barry