[PATCH sched_ext/for-7.1-fixes] tools/sched_ext: Add missing -d option in scx_flatcg

[PATCH sched_ext/for-7.1-fixes] tools/sched_ext: Add missing -d option in scx_flatcg

[Cheng-Yang Chou]

Add missing -d option to help_fmt to reflect the capability.

Signed-off-by: Cheng-Yang Chou <yphbchou0911@gmail.com>
---
 tools/sched_ext/scx_flatcg.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/sched_ext/scx_flatcg.c b/tools/sched_ext/scx_flatcg.c
index d865c381589b..fa27352f9a6d 100644
--- a/tools/sched_ext/scx_flatcg.c
+++ b/tools/sched_ext/scx_flatcg.c
@@ -27,10 +27,11 @@ const char help_fmt[] =
 "\n"
 "See the top-level comment in .bpf.c for more details.\n"
 "\n"
-"Usage: %s [-s SLICE_US] [-i INTERVAL] [-f] [-v]\n"
+"Usage: %s [-s SLICE_US] [-i INTERVAL] [-d] [-f] [-v]\n"
 "\n"
 "  -s SLICE_US   Override slice duration\n"
 "  -i INTERVAL   Report interval\n"
+"  -d            Dump cgroup hierarchy on start\n"
 "  -f            Use FIFO scheduling instead of weighted vtime scheduling\n"
 "  -v            Print libbpf debug messages\n"
 "  -h            Display this help and exit\n";
-- 
2.48.1

Re: [PATCH sched_ext/for-7.1-fixes] tools/sched_ext: Add missing -d option in scx_flatcg

[Tejun Heo]

Hello,

-d is dead code - it just sets dump_cgrps which is only echoed in the
status-line printf, nothing actually dumps the cgroup hierarchy. The
right thing to do is remove the whole thing - the 'd' in getopt(), case
'd':, the dump_cgrps variable and its printf - rather than document dead
code as a feature.

Want to spin a removal patch?

Thanks.

-- 
tejun

Re: [PATCH sched_ext/for-7.1-fixes] tools/sched_ext: Add missing -d option in scx_flatcg

[Cheng-Yang Chou]

Hi Tejun,

On Sun, Apr 19, 2026 at 06:04:34AM -1000, Tejun Heo wrote:
> -d is dead code - it just sets dump_cgrps which is only echoed in the
> status-line printf, nothing actually dumps the cgroup hierarchy. The
> right thing to do is remove the whole thing - the 'd' in getopt(), case
> 'd':, the dump_cgrps variable and its printf - rather than document dead
> code as a feature.
> 
> Want to spin a removal patch?

Yeah, for sure! Thanks for the explanation, will do!

-- 
Cheers,
Cheng-Yang