Commit-ID: c4544dbc7a9bce3da6fa2361cd68cadb34e9221f Gitweb: http://git.kernel.org/tip/c4544dbc7a9bce3da6fa2361cd68cadb34e9221f Author: Sebastian Andrzej Siewior <[email protected]> AuthorDate: Thu, 18 Aug 2016 14:57:21 +0200 Committer: Thomas Gleixner <[email protected]> CommitDate: Tue, 6 Sep 2016 18:30:22 +0200
kernel/softirq: Convert to hotplug state machine Install the callbacks via the state machine. Signed-off-by: Sebastian Andrzej Siewior <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]> --- include/linux/cpuhotplug.h | 1 + kernel/softirq.c | 27 ++++++--------------------- 2 files changed, 7 insertions(+), 21 deletions(-) diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 854e59a..a421407 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -17,6 +17,7 @@ enum cpuhp_state { CPUHP_VIRT_NET_DEAD, CPUHP_SLUB_DEAD, CPUHP_MM_WRITEBACK_DEAD, + CPUHP_SOFTIRQ_DEAD, CPUHP_WORKQUEUE_PREP, CPUHP_POWER_NUMA_PREPARE, CPUHP_HRTIMERS_PREPARE, diff --git a/kernel/softirq.c b/kernel/softirq.c index 17caf4b..c372114 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -700,7 +700,7 @@ void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu) BUG(); } -static void takeover_tasklets(unsigned int cpu) +static int takeover_tasklets(unsigned int cpu) { /* CPU is dead, so no lock needed. */ local_irq_disable(); @@ -723,27 +723,12 @@ static void takeover_tasklets(unsigned int cpu) raise_softirq_irqoff(HI_SOFTIRQ); local_irq_enable(); + return 0; } +#else +#define takeover_tasklets NULL #endif /* CONFIG_HOTPLUG_CPU */ -static int cpu_callback(struct notifier_block *nfb, unsigned long action, - void *hcpu) -{ - switch (action) { -#ifdef CONFIG_HOTPLUG_CPU - case CPU_DEAD: - case CPU_DEAD_FROZEN: - takeover_tasklets((unsigned long)hcpu); - break; -#endif /* CONFIG_HOTPLUG_CPU */ - } - return NOTIFY_OK; -} - -static struct notifier_block cpu_nfb = { - .notifier_call = cpu_callback -}; - static struct smp_hotplug_thread softirq_threads = { .store = &ksoftirqd, .thread_should_run = ksoftirqd_should_run, @@ -753,8 +738,8 @@ static struct smp_hotplug_thread softirq_threads = { static __init int spawn_ksoftirqd(void) { - register_cpu_notifier(&cpu_nfb); - + cpuhp_setup_state_nocalls(CPUHP_SOFTIRQ_DEAD, "softirq:dead", NULL, + takeover_tasklets); BUG_ON(smpboot_register_percpu_thread(&softirq_threads)); return 0;
