The following commit has been merged into the smp/core branch of tip: Commit-ID: d308077e5e4dc8c93f97f5ebc70274e7c7a92d49 Gitweb: https://git.kernel.org/tip/d308077e5e4dc8c93f97f5ebc70274e7c7a92d49 Author: Steven Price <steven.price@xxxxxxx> AuthorDate: Mon, 11 Apr 2022 16:22:33 +01:00 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Wed, 13 Apr 2022 21:27:41 +02:00 cpu/hotplug: Initialise all cpuhp_cpu_state structs earlier Rather than waiting until a CPU is first brought online, do the initialisation of the cpuhp_cpu_state structure for each CPU during the __init phase. This saves a (small) amount of non-__init memory and avoids potential confusion about when the cpuhp_cpu_state struct is valid. Suggested-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Steven Price <steven.price@xxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220411152233.474129-3-steven.price@xxxxxxx --- kernel/cpu.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/kernel/cpu.c b/kernel/cpu.c index d0a9aa0..02a77ac 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -716,14 +716,6 @@ static int cpuhp_up_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, /* * The cpu hotplug threads manage the bringup and teardown of the cpus */ -static void cpuhp_create(unsigned int cpu) -{ - struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); - - init_completion(&st->done_up); - init_completion(&st->done_down); -} - static int cpuhp_should_run(unsigned int cpu) { struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); @@ -883,15 +875,27 @@ static int cpuhp_kick_ap_work(unsigned int cpu) static struct smp_hotplug_thread cpuhp_threads = { .store = &cpuhp_state.thread, - .create = &cpuhp_create, .thread_should_run = cpuhp_should_run, .thread_fn = cpuhp_thread_fun, .thread_comm = "cpuhp/%u", .selfparking = true, }; +static __init void cpuhp_init_state(void) +{ + struct cpuhp_cpu_state *st; + int cpu; + + for_each_possible_cpu(cpu) { + st = per_cpu_ptr(&cpuhp_state, cpu); + init_completion(&st->done_up); + init_completion(&st->done_down); + } +} + void __init cpuhp_threads_init(void) { + cpuhp_init_state(); BUG_ON(smpboot_register_percpu_thread(&cpuhp_threads)); kthread_unpark(this_cpu_read(cpuhp_state.thread)); }
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