From: Jake Hillion <jake@hillion.co.uk> mainline inclusion from mainline-v6.15-rc1 commit a8897ed8523d4c9d782e282b18005a3779c92714 category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8335 Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commi... -------------------------------- create_dsq and therefore the scx_bpf_create_dsq kfunc currently silently ignore duplicate entries. As a sched_ext scheduler is creating each DSQ for a different purpose this is surprising behaviour. Replace rhashtable_insert_fast which ignores duplicates with rhashtable_lookup_insert_fast that reports duplicates (though doesn't return their value). The rest of the code is structured correctly and this now returns -EEXIST. Tested by adding an extra scx_bpf_create_dsq to scx_simple. Previously this was ignored, now init fails with a -17 code. Also ran scx_lavd which continued to work well. Signed-off-by: Jake Hillion <jake@hillion.co.uk> Acked-by: Andrea Righi <arighi@nvidia.com> Fixes: f0e1a0643a59 ("sched_ext: Implement BPF extensible scheduler class") Cc: stable@vger.kernel.org # v6.12+ Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Zicheng Qu <quzicheng@huawei.com> Signed-off-by: cheliequan <cheliequan@inspur.com> Signed-off-by: Luo Gengkun <luogengkun2@huawei.com> --- kernel/sched/ext.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index beeb9500ac9c..36bc9aee9bcc 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4531,8 +4531,8 @@ static struct scx_dispatch_q *create_dsq(u64 dsq_id, int node) init_dsq(dsq, dsq_id); - ret = rhashtable_insert_fast(&dsq_hash, &dsq->hash_node, - dsq_hash_params); + ret = rhashtable_lookup_insert_fast(&dsq_hash, &dsq->hash_node, + dsq_hash_params); if (ret) { kfree(dsq); return ERR_PTR(ret); -- 2.34.1