softirq: Move various protections into inline helpers
To allow reuse of the bulk of softirq processing code for RT and to avoid
#ifdeffery all over the place, split protections for various code sections
out into inline helpers so the RT variant can just replace them in one go.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309085727.310118772@linutronix.de
diff --git a/kernel/softirq.c b/kernel/softirq.c
index f1eb83d..eaca3337 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -207,6 +207,32 @@ void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
}
EXPORT_SYMBOL(__local_bh_enable_ip);
+static inline void softirq_handle_begin(void)
+{
+ __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+}
+
+static inline void softirq_handle_end(void)
+{
+ __local_bh_enable(SOFTIRQ_OFFSET);
+ WARN_ON_ONCE(in_interrupt());
+}
+
+static inline void ksoftirqd_run_begin(void)
+{
+ local_irq_disable();
+}
+
+static inline void ksoftirqd_run_end(void)
+{
+ local_irq_enable();
+}
+
+static inline bool should_wake_ksoftirqd(void)
+{
+ return true;
+}
+
static inline void invoke_softirq(void)
{
if (ksoftirqd_running(local_softirq_pending()))
@@ -319,7 +345,7 @@ asmlinkage __visible void __softirq_entry __do_softirq(void)
pending = local_softirq_pending();
- __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET);
+ softirq_handle_begin();
in_hardirq = lockdep_softirq_start();
account_softirq_enter(current);
@@ -370,8 +396,7 @@ asmlinkage __visible void __softirq_entry __do_softirq(void)
account_softirq_exit(current);
lockdep_softirq_end(in_hardirq);
- __local_bh_enable(SOFTIRQ_OFFSET);
- WARN_ON_ONCE(in_interrupt());
+ softirq_handle_end();
current_restore_flags(old_flags, PF_MEMALLOC);
}
@@ -466,7 +491,7 @@ inline void raise_softirq_irqoff(unsigned int nr)
* Otherwise we wake up ksoftirqd to make sure we
* schedule the softirq soon.
*/
- if (!in_interrupt())
+ if (!in_interrupt() && should_wake_ksoftirqd())
wakeup_softirqd();
}
@@ -698,18 +723,18 @@ static int ksoftirqd_should_run(unsigned int cpu)
static void run_ksoftirqd(unsigned int cpu)
{
- local_irq_disable();
+ ksoftirqd_run_begin();
if (local_softirq_pending()) {
/*
* We can safely run softirq on inline stack, as we are not deep
* in the task stack here.
*/
__do_softirq();
- local_irq_enable();
+ ksoftirqd_run_end();
cond_resched();
return;
}
- local_irq_enable();
+ ksoftirqd_run_end();
}
#ifdef CONFIG_HOTPLUG_CPU
