From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> All users converted to the hotplug core mechanism. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> --- include/linux/cpu.h | 2 - kernel/smpboot.c | 75 ---------------------------------------------------- 2 files changed, 77 deletions(-) --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -193,8 +193,6 @@ static inline void play_idle(unsigned lo } #ifdef CONFIG_HOTPLUG_CPU -bool cpu_wait_death(unsigned int cpu, int seconds); -bool cpu_report_death(void); void cpuhp_report_idle_dead(void); #else static inline void cpuhp_report_idle_dead(void) { } --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -325,78 +325,3 @@ void smpboot_unregister_percpu_thread(st cpus_read_unlock(); } EXPORT_SYMBOL_GPL(smpboot_unregister_percpu_thread); - -#ifndef CONFIG_HOTPLUG_CORE_SYNC -static DEFINE_PER_CPU(atomic_t, cpu_hotplug_state) = ATOMIC_INIT(CPU_POST_DEAD); - -#ifdef CONFIG_HOTPLUG_CPU -/* - * Wait for the specified CPU to exit the idle loop and die. - */ -bool cpu_wait_death(unsigned int cpu, int seconds) -{ - int jf_left = seconds * HZ; - int oldstate; - bool ret = true; - int sleep_jf = 1; - - might_sleep(); - - /* The outgoing CPU will normally get done quite quickly. */ - if (atomic_read(&per_cpu(cpu_hotplug_state, cpu)) == CPU_DEAD) - goto update_state_early; - udelay(5); - - /* But if the outgoing CPU dawdles, wait increasingly long times. */ - while (atomic_read(&per_cpu(cpu_hotplug_state, cpu)) != CPU_DEAD) { - schedule_timeout_uninterruptible(sleep_jf); - jf_left -= sleep_jf; - if (jf_left <= 0) - break; - sleep_jf = DIV_ROUND_UP(sleep_jf * 11, 10); - } -update_state_early: - oldstate = atomic_read(&per_cpu(cpu_hotplug_state, cpu)); -update_state: - if (oldstate == CPU_DEAD) { - /* Outgoing CPU died normally, update state. */ - smp_mb(); /* atomic_read() before update. */ - atomic_set(&per_cpu(cpu_hotplug_state, cpu), CPU_POST_DEAD); - } else { - /* Outgoing CPU still hasn't died, set state accordingly. */ - if (!atomic_try_cmpxchg(&per_cpu(cpu_hotplug_state, cpu), - &oldstate, CPU_BROKEN)) - goto update_state; - ret = false; - } - return ret; -} - -/* - * Called by the outgoing CPU to report its successful death. Return - * false if this report follows the surviving CPU's timing out. - * - * A separate "CPU_DEAD_FROZEN" is used when the surviving CPU - * timed out. This approach allows architectures to omit calls to - * cpu_check_up_prepare() and cpu_set_state_online() without defeating - * the next cpu_wait_death()'s polling loop. - */ -bool cpu_report_death(void) -{ - int oldstate; - int newstate; - int cpu = smp_processor_id(); - - oldstate = atomic_read(&per_cpu(cpu_hotplug_state, cpu)); - do { - if (oldstate != CPU_BROKEN) - newstate = CPU_DEAD; - else - newstate = CPU_DEAD_FROZEN; - } while (!atomic_try_cmpxchg(&per_cpu(cpu_hotplug_state, cpu), - &oldstate, newstate)); - return newstate == CPU_DEAD; -} - -#endif /* #ifdef CONFIG_HOTPLUG_CPU */ -#endif /* !CONFIG_HOTPLUG_CORE_SYNC */