[PATCH v6 01/17] ARM, sched/topology: Remove SD_SHARE_POWERDOMAIN

From: Valentin Schneider
Date: Mon Aug 17 2020 - 07:30:20 EST


This flag was introduced in 2014 by commit

d77b3ed5c9f8 ("sched: Add a new SD_SHARE_POWERDOMAIN for sched_domain")

but AFAIA it was never leveraged by the scheduler. The closest thing I can
think of is EAS caring about frequency domains, and it does that by
leveraging performance domains.

Remove the flag. No change in functionality is expected.

Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Suggested-by: Morten Rasmussen <morten.rasmussen@xxxxxxx>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
Signed-off-by: Valentin Schneider <valentin.schneider@xxxxxxx>
---
arch/arm/kernel/topology.c | 2 +-
include/linux/sched/topology.h | 13 ++++++-------
kernel/sched/topology.c | 10 +++-------
3 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c
index b5adaf744630..353f3ee660e4 100644
--- a/arch/arm/kernel/topology.c
+++ b/arch/arm/kernel/topology.c
@@ -243,7 +243,7 @@ void store_cpu_topology(unsigned int cpuid)

static inline int cpu_corepower_flags(void)
{
- return SD_SHARE_PKG_RESOURCES | SD_SHARE_POWERDOMAIN;
+ return SD_SHARE_PKG_RESOURCES;
}

static struct sched_domain_topology_level arm_topology[] = {
diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index 820511289857..6ec7d7c1d1e3 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -18,13 +18,12 @@
#define SD_WAKE_AFFINE 0x0010 /* Wake task to waking CPU */
#define SD_ASYM_CPUCAPACITY 0x0020 /* Domain members have different CPU capacities */
#define SD_SHARE_CPUCAPACITY 0x0040 /* Domain members share CPU capacity */
-#define SD_SHARE_POWERDOMAIN 0x0080 /* Domain members share power domain */
-#define SD_SHARE_PKG_RESOURCES 0x0100 /* Domain members share CPU pkg resources */
-#define SD_SERIALIZE 0x0200 /* Only a single load balancing instance */
-#define SD_ASYM_PACKING 0x0400 /* Place busy groups earlier in the domain */
-#define SD_PREFER_SIBLING 0x0800 /* Prefer to place tasks in a sibling domain */
-#define SD_OVERLAP 0x1000 /* sched_domains of this level overlap */
-#define SD_NUMA 0x2000 /* cross-node balancing */
+#define SD_SHARE_PKG_RESOURCES 0x0080 /* Domain members share CPU pkg resources */
+#define SD_SERIALIZE 0x0100 /* Only a single load balancing instance */
+#define SD_ASYM_PACKING 0x0200 /* Place busy groups earlier in the domain */
+#define SD_PREFER_SIBLING 0x0400 /* Prefer to place tasks in a sibling domain */
+#define SD_OVERLAP 0x0800 /* sched_domains of this level overlap */
+#define SD_NUMA 0x1000 /* cross-node balancing */

#ifdef CONFIG_SCHED_SMT
static inline int cpu_smt_flags(void)
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 9079d865a935..865fff3ef20a 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -148,8 +148,7 @@ static int sd_degenerate(struct sched_domain *sd)
SD_BALANCE_EXEC |
SD_SHARE_CPUCAPACITY |
SD_ASYM_CPUCAPACITY |
- SD_SHARE_PKG_RESOURCES |
- SD_SHARE_POWERDOMAIN)) {
+ SD_SHARE_PKG_RESOURCES)) {
if (sd->groups != sd->groups->next)
return 0;
}
@@ -180,8 +179,7 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
SD_ASYM_CPUCAPACITY |
SD_SHARE_CPUCAPACITY |
SD_SHARE_PKG_RESOURCES |
- SD_PREFER_SIBLING |
- SD_SHARE_POWERDOMAIN);
+ SD_PREFER_SIBLING);
if (nr_node_ids == 1)
pflags &= ~SD_SERIALIZE;
}
@@ -1292,7 +1290,6 @@ int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE;
* SD_SHARE_CPUCAPACITY - describes SMT topologies
* SD_SHARE_PKG_RESOURCES - describes shared caches
* SD_NUMA - describes NUMA topologies
- * SD_SHARE_POWERDOMAIN - describes shared power domain
*
* Odd one out, which beside describing the topology has a quirk also
* prescribes the desired behaviour that goes along with it:
@@ -1303,8 +1300,7 @@ int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE;
(SD_SHARE_CPUCAPACITY | \
SD_SHARE_PKG_RESOURCES | \
SD_NUMA | \
- SD_ASYM_PACKING | \
- SD_SHARE_POWERDOMAIN)
+ SD_ASYM_PACKING)

static struct sched_domain *
sd_init(struct sched_domain_topology_level *tl,
--
2.27.0