Re: [RFC][PATCH] sched: Rename DIE domain

From: Valentin Schneider
Date: Wed Jul 12 2023 - 11:03:43 EST


On 12/07/23 16:10, Peter Zijlstra wrote:
> Hi
>
> Thomas just tripped over the x86 topology setup creating a 'DIE' domain
> for the package mask :-)
>
> Since these names are SCHED_DEBUG only, rename them.
> I don't think anybody *should* be relying on this, but who knows.
>

FWIW I don't care much about the actual name.

There are some stray references to DIE in comments - see below. Bit funny
to see:
- * - Package (DIE)
+ * - Package (PKG)

With that:
Acked-by: Valentin Schneider <vschneid@xxxxxxxxxx>

---
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a80a73909dc2a..190a647534984 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9439,7 +9439,7 @@ static bool sched_use_asym_prio(struct sched_domain *sd, int cpu)
* can only do it if @group is an SMT group and has exactly on busy CPU. Larger
* imbalances in the number of CPUS are dealt with in find_busiest_group().
*
- * If we are balancing load within an SMT core, or at DIE domain level, always
+ * If we are balancing load within an SMT core, or at PKG domain level, always
* proceed.
*
* Return: true if @env::dst_cpu can do with asym_packing load balance. False
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index e9d9cf776b7ab..2cdcfec1d1c89 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1118,7 +1118,7 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
*
* - Simultaneous multithreading (SMT)
* - Multi-Core Cache (MC)
- * - Package (DIE)
+ * - Package (PKG)
*
* Where the last one more or less denotes everything up to a NUMA node.
*
@@ -1140,13 +1140,13 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
*
* CPU 0 1 2 3 4 5 6 7
*
- * DIE [ ]
+ * PKG [ ]
* MC [ ] [ ]
* SMT [ ] [ ] [ ] [ ]
*
* - or -
*
- * DIE 0-7 0-7 0-7 0-7 0-7 0-7 0-7 0-7
+ * PKG 0-7 0-7 0-7 0-7 0-7 0-7 0-7 0-7
* MC 0-3 0-3 0-3 0-3 4-7 4-7 4-7 4-7
* SMT 0-1 0-1 2-3 2-3 4-5 4-5 6-7 6-7
*