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| author | Thomas Gleixner <tglx@kernel.org> | 2026-03-10 21:29:09 +0100 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-03-11 12:01:07 +0100 |
| commit | 192d852129b1b7c4f0ddbab95d0de1efd5ee1405 (patch) | |
| tree | b683e4093b5c8b4366556c818a3fe95ed00015b7 /kernel/fork.c | |
| parent | 7574ac6e49789ddee1b1be9b2afb42b4a1b4b1f4 (diff) | |
| download | linux-192d852129b1b7c4f0ddbab95d0de1efd5ee1405.tar.gz linux-192d852129b1b7c4f0ddbab95d0de1efd5ee1405.zip | |
sched/mmcid: Avoid full tasklist walks
Chasing vfork()'ed tasks on a CID ownership mode switch requires a full
task list walk, which is obviously expensive on large systems.
Avoid that by keeping a list of tasks using a mm MMCID entity in mm::mm_cid
and walk this list instead. This removes the proven to be flaky counting
logic and avoids a full task list walk in the case of vfork()'ed tasks.
Fixes: fbd0e71dc370 ("sched/mmcid: Provide CID ownership mode fixup functions")
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260310202526.183824481@kernel.org
Diffstat (limited to 'kernel/fork.c')
| -rw-r--r-- | kernel/fork.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 7febf4c2889e..bc2bf58b93b6 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1000,6 +1000,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) #ifdef CONFIG_SCHED_MM_CID tsk->mm_cid.cid = MM_CID_UNSET; tsk->mm_cid.active = 0; + INIT_HLIST_NODE(&tsk->mm_cid.node); #endif return tsk; |