[tip: sched/core] sched/debug: Dump domains' sched group flags

[tip-bot2 for Peter Zijlstra]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     ed74cc4995d314ea6cbf406caf978c442f451fa5
Gitweb:        https://git.kernel.org/tip/ed74cc4995d314ea6cbf406caf978c442f451fa5
Author:        Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate:    Fri, 07 Jul 2023 15:57:05 -07:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Thu, 13 Jul 2023 15:21:53 +02:00

sched/debug: Dump domains' sched group flags

There have been a case where the SD_SHARE_CPUCAPACITY sched group flag
in a parent domain were not set and propagated properly when a degenerate
domain is removed.

Add dump of domain sched group flags of a CPU to make debug easier
in the future.

Usage:
cat /debug/sched/domains/cpu0/domain1/groups_flags
to dump cpu0 domain1's sched group flags.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Valentin Schneider <vschneid@xxxxxxxxxx>
Link: https://lore.kernel.org/r/ed1749262d94d95a8296c86a415999eda90bcfe3.1688770494.git.tim.c.chen@xxxxxxxxxxxxxxx
---
 kernel/sched/debug.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 066ff1c..aeeba46 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -427,6 +427,7 @@ static void register_sd(struct sched_domain *sd, struct dentry *parent)
 #undef SDM
 
 	debugfs_create_file("flags", 0444, parent, &sd->flags, &sd_flags_fops);
+	debugfs_create_file("groups_flags", 0444, parent, &sd->groups->flags, &sd_flags_fops);
 }
 
 void update_sched_domain_debugfs(void)