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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: rspam10 X-Rspamd-Queue-Id: 7D7231A000A X-Stat-Signature: paqbrmy7yhrauw1d834g9a9broscjsna X-Rspam-User: X-HE-Tag: 1770361582-460629 X-HE-Meta: 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 EljtYA/+ 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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: The kcompactd threads should respect the housekeeping mask for kthreads (HK_TYPE_KTHREAD) to avoid running on isolated CPUs. Currently, they are created without explicit affinity constraints beyond the node preference. Add housekeeping_affine() to kcompactd_run() to set initial affinity, and register a housekeeping notifier to update kcompactd affinity when the HK_TYPE_KTHREAD mask is changed at runtime. Signed-off-by: Qiliang Yuan Signed-off-by: Qiliang Yuan --- mm/compaction.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/mm/compaction.c b/mm/compaction.c index 1e8f8eca318c..495106d970f1 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -24,6 +24,7 @@ #include #include #include +#include #include "internal.h" #ifdef CONFIG_COMPACTION @@ -3246,6 +3247,7 @@ void __meminit kcompactd_run(int nid) pr_err("Failed to start kcompactd on node %d\n", nid); pgdat->kcompactd = NULL; } else { + housekeeping_affine(pgdat->kcompactd, HK_TYPE_KTHREAD); wake_up_process(pgdat->kcompactd); } } @@ -3320,6 +3322,29 @@ static const struct ctl_table vm_compaction[] = { }, }; +static int kcompactd_housekeeping_reconfigure(struct notifier_block *nb, + unsigned long action, void *data) +{ + unsigned int type = (unsigned long)data; + + if (action == HK_UPDATE_MASK && type == HK_TYPE_KTHREAD) { + int nid; + + for_each_node_state(nid, N_MEMORY) { + pg_data_t *pgdat = NODE_DATA(nid); + + if (pgdat->kcompactd) + housekeeping_affine(pgdat->kcompactd, HK_TYPE_KTHREAD); + } + } + + return NOTIFY_OK; +} + +static struct notifier_block kcompactd_housekeeping_nb = { + .notifier_call = kcompactd_housekeeping_reconfigure, +}; + static int __init kcompactd_init(void) { int nid; @@ -3327,6 +3352,7 @@ static int __init kcompactd_init(void) for_each_node_state(nid, N_MEMORY) kcompactd_run(nid); register_sysctl_init("vm", vm_compaction); + housekeeping_register_notifier(&kcompactd_housekeeping_nb); return 0; } subsys_initcall(kcompactd_init) -- 2.51.0