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McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Tejun Heo , Andrew Morton , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , Anna-Maria Behnsen , Ingo Molnar Cc: linux-kernel@vger.kernel.org, rcu@vger.kernel.org, linux-mm@kvack.org, Qiliang Yuan , Qiliang Yuan X-Mailer: b4 0.14.3 X-Rspamd-Server: rspam11 X-Stat-Signature: 5pg85jpux3td6wuaroi3s3s8kj5kkgoa X-Rspam-User: X-Rspamd-Queue-Id: 369A514000B X-HE-Tag: 1770361547-341878 X-HE-Meta: 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 JezRcsLl 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: When the housekeeping CPU mask for RCU is updated at runtime, RCU grace-period kthreads and tasks-RCU kthreads should be migrated to the newly designated housekeeping CPUs. 1. Implement rcu_housekeeping_reconfigure() to handle HK_UPDATE_MASK events for HK_TYPE_RCU. 2. Update the affinity of rcu_state.gp_kthread when the mask changes. 3. Register the RCU housekeeping notifier during late initialization. This ensures RCU kthreads honor dynamic isolation settings without requiring a system reboot. Signed-off-by: Qiliang Yuan Signed-off-by: Qiliang Yuan --- kernel/rcu/tree.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 293bbd9ac3f4..ec496e4bd24f 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -48,6 +48,7 @@ #include #include #include +#include #include #include #include @@ -4913,7 +4914,49 @@ void __init rcu_init(void) tasks_cblist_init_generic(); } +#ifdef CONFIG_SMP +static int rcu_housekeeping_reconfigure(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct housekeeping_update *upd = data; + struct task_struct *t; + + if (action != HK_UPDATE_MASK || upd->type != HK_TYPE_RCU) + return NOTIFY_OK; + + t = READ_ONCE(rcu_state.gp_kthread); + if (t) + housekeeping_affine(t, HK_TYPE_RCU); + +#ifdef CONFIG_TASKS_RCU + t = get_rcu_tasks_gp_kthread(); + if (t) + housekeeping_affine(t, HK_TYPE_RCU); +#endif + +#ifdef CONFIG_TASKS_RUDE_RCU + t = get_rcu_tasks_rude_gp_kthread(); + if (t) + housekeeping_affine(t, HK_TYPE_RCU); +#endif + + return NOTIFY_OK; +} + +static struct notifier_block rcu_housekeeping_nb = { + .notifier_call = rcu_housekeeping_reconfigure, +}; + +static int __init rcu_init_housekeeping_notifier(void) +{ + housekeeping_register_notifier(&rcu_housekeeping_nb); + return 0; +} +late_initcall(rcu_init_housekeeping_notifier); +#endif + #include "tree_stall.h" #include "tree_exp.h" #include "tree_nocb.h" #include "tree_plugin.h" + -- 2.51.0