tizen: Use unique directory prefix for baselibs packages

[platform/kernel/linux-rpi.git] / kernel / softirq.c

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 210cf5f..cae0ae2 100644 (file)
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -247,6 +247,19 @@ out:
 }
 EXPORT_SYMBOL(__local_bh_enable_ip);
 
+void softirq_preempt(void)
+{
+       if (WARN_ON_ONCE(!preemptible()))
+               return;
+
+       if (WARN_ON_ONCE(__this_cpu_read(softirq_ctrl.cnt) != SOFTIRQ_OFFSET))
+               return;
+
+       __local_bh_enable(SOFTIRQ_OFFSET, true);
+       /* preemption point */
+       __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+}
+
 /*
  * Invoked from ksoftirqd_run() outside of the interrupt disabled section
  * to acquire the per CPU local lock for reentrancy protection.
@@ -619,6 +632,24 @@ static inline void tick_irq_exit(void)
 #endif
 }
 
+#ifdef CONFIG_PREEMPT_RT
+DEFINE_PER_CPU(struct task_struct *, timersd);
+DEFINE_PER_CPU(unsigned long, pending_timer_softirq);
+
+static void wake_timersd(void)
+{
+        struct task_struct *tsk = __this_cpu_read(timersd);
+
+        if (tsk)
+                wake_up_process(tsk);
+}
+
+#else
+
+static inline void wake_timersd(void) { }
+
+#endif
+
 static inline void __irq_exit_rcu(void)
 {
 #ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED
@@ -631,6 +662,10 @@ static inline void __irq_exit_rcu(void)
        if (!in_interrupt() && local_softirq_pending())
                invoke_softirq();
 
+       if (IS_ENABLED(CONFIG_PREEMPT_RT) && local_pending_timers() &&
+           !(in_nmi() | in_hardirq()))
+               wake_timersd();
+
        tick_irq_exit();
 }
 
@@ -963,12 +998,70 @@ static struct smp_hotplug_thread softirq_threads = {
        .thread_comm            = "ksoftirqd/%u",
 };
 
+#ifdef CONFIG_PREEMPT_RT
+static void timersd_setup(unsigned int cpu)
+{
+        sched_set_fifo_low(current);
+}
+
+static int timersd_should_run(unsigned int cpu)
+{
+        return local_pending_timers();
+}
+
+static void run_timersd(unsigned int cpu)
+{
+       unsigned int timer_si;
+
+       ksoftirqd_run_begin();
+
+       timer_si = local_pending_timers();
+       __this_cpu_write(pending_timer_softirq, 0);
+       or_softirq_pending(timer_si);
+
+       __do_softirq();
+
+       ksoftirqd_run_end();
+}
+
+static void raise_ktimers_thread(unsigned int nr)
+{
+       trace_softirq_raise(nr);
+       __this_cpu_or(pending_timer_softirq, 1 << nr);
+}
+
+void raise_hrtimer_softirq(void)
+{
+       raise_ktimers_thread(HRTIMER_SOFTIRQ);
+}
+
+void raise_timer_softirq(void)
+{
+       unsigned long flags;
+
+       local_irq_save(flags);
+       raise_ktimers_thread(TIMER_SOFTIRQ);
+       wake_timersd();
+       local_irq_restore(flags);
+}
+
+static struct smp_hotplug_thread timer_threads = {
+        .store                  = &timersd,
+        .setup                  = timersd_setup,
+        .thread_should_run      = timersd_should_run,
+        .thread_fn              = run_timersd,
+        .thread_comm            = "ktimers/%u",
+};
+#endif
+
 static __init int spawn_ksoftirqd(void)
 {
        cpuhp_setup_state_nocalls(CPUHP_SOFTIRQ_DEAD, "softirq:dead", NULL,
                                  takeover_tasklets);
        BUG_ON(smpboot_register_percpu_thread(&softirq_threads));
-
+#ifdef CONFIG_PREEMPT_RT
+       BUG_ON(smpboot_register_percpu_thread(&timer_threads));
+#endif
        return 0;
 }
 early_initcall(spawn_ksoftirqd);