Commit 8cbb2b50 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Arnd Bergmann
Browse files

asm-generic: Conditionally enable do_softirq_own_stack() via Kconfig. 

Remove the CONFIG_PREEMPT_RT symbol from the ifdef around
do_softirq_own_stack() and move it to Kconfig instead.

Enable softirq stacks based on SOFTIRQ_ON_OWN_STACK which depends on
HAVE_SOFTIRQ_ON_OWN_STACK and its default value is set to !PREEMPT_RT.
This ensures that softirq stacks are not used on PREEMPT_RT and avoids
a 'select' statement on an option which has a 'depends' statement.

Link: https://lore.kernel.org/YvN5E%2FPrHfUhggr7@linutronix.de


Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parent b90cb105

arch/Kconfig

+3 −0
Original line number Diff line number Diff line
@@ -923,6 +923,9 @@ config HAVE_SOFTIRQ_ON_OWN_STACK 
	  Architecture provides a function to run __do_softirq() on a

	  separate stack.



config SOFTIRQ_ON_OWN_STACK

	def_bool HAVE_SOFTIRQ_ON_OWN_STACK && !PREEMPT_RT



config ALTERNATE_USER_ADDRESS_SPACE

	bool

	help

arch/arm/kernel/irq.c

+1 −1
Original line number Diff line number Diff line
@@ -70,7 +70,7 @@ static void __init init_irq_stacks(void) 
	}

}



#ifndef CONFIG_PREEMPT_RT

#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK

static void ____do_softirq(void *arg)

{

	__do_softirq();

arch/parisc/kernel/irq.c

+1 −1
Original line number Diff line number Diff line
@@ -480,7 +480,7 @@ static void execute_on_irq_stack(void *func, unsigned long param1) 
	*irq_stack_in_use = 1;

}



#ifndef CONFIG_PREEMPT_RT

#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK

void do_softirq_own_stack(void)

{

	execute_on_irq_stack(__do_softirq, 0);

arch/powerpc/kernel/irq.c

+2 −2
Original line number Diff line number Diff line
@@ -199,7 +199,7 @@ static inline void check_stack_overflow(unsigned long sp) 
	}

}



#ifndef CONFIG_PREEMPT_RT

#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK

static __always_inline void call_do_softirq(const void *sp)

{

	/* Temporarily switch r1 to sp, call __do_softirq() then restore r1. */
@@ -335,7 +335,7 @@ void *mcheckirq_ctx[NR_CPUS] __read_mostly; 
void *softirq_ctx[NR_CPUS] __read_mostly;

void *hardirq_ctx[NR_CPUS] __read_mostly;



#ifndef CONFIG_PREEMPT_RT

#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK

void do_softirq_own_stack(void)

{

	call_do_softirq(softirq_ctx[smp_processor_id()]);

arch/s390/include/asm/softirq_stack.h

+1 −1
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
#include <asm/lowcore.h>

#include <asm/stacktrace.h>



#ifndef CONFIG_PREEMPT_RT

#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK

static inline void do_softirq_own_stack(void)

{

	call_on_stack(0, S390_lowcore.async_stack, void, __do_softirq);