Commit f02fc963 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

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: default avatarThomas Gleixner <tglx@linutronix.de>
Tested-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Reviewed-by: default avatarFrederic Weisbecker <frederic@kernel.org>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309085727.310118772@linutronix.de
parent 6516b386

kernel/softirq.c

+32 −7
Original line number Diff line number Diff line
@@ -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