diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2021-09-24 18:05:48 +0300 |
|---|---|---|
| committer | Minda Chen <minda.chen@starfivetech.com> | 2023-11-06 14:24:49 +0300 |
| commit | 346b840b6cf5bd676f37110d18602ceee8c09ee6 (patch) | |
| tree | 58d1887a3aaa3006ce675bc797a6df8915b15f70 | |
| parent | 1bd9479c50b6cb6c590dc8ddcc469cd2b7bd3b5d (diff) | |
| download | linux-346b840b6cf5bd676f37110d18602ceee8c09ee6.tar.xz | |
*/softirq: Disable softirq stacks on PREEMPT_RT
PREEMPT_RT preempts softirqs and the current implementation avoids
do_softirq_own_stack() and only uses __do_softirq().
Disable the unused softirqs stacks on PREEMPT_RT to safe some memory and
ensure that do_softirq_own_stack() is not used which is not expected.
[bigeasy: commit description.]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
| -rw-r--r-- | arch/powerpc/kernel/irq.c | 4 | ||||
| -rw-r--r-- | arch/sh/kernel/irq.c | 2 | ||||
| -rw-r--r-- | arch/sparc/kernel/irq_64.c | 2 |
3 files changed, 8 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index c4f1d6b7d992..02e17a57da83 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -690,6 +690,7 @@ static inline void check_stack_overflow(void) } } +#ifndef CONFIG_PREEMPT_RT static __always_inline void call_do_softirq(const void *sp) { /* Temporarily switch r1 to sp, call __do_softirq() then restore r1. */ @@ -708,6 +709,7 @@ static __always_inline void call_do_softirq(const void *sp) "r11", "r12" ); } +#endif static __always_inline void call_do_irq(struct pt_regs *regs, void *sp) { @@ -820,10 +822,12 @@ 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 void do_softirq_own_stack(void) { call_do_softirq(softirq_ctx[smp_processor_id()]); } +#endif irq_hw_number_t virq_to_hw(unsigned int virq) { diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c index ef0f0827cf57..2d3eca8fee01 100644 --- a/arch/sh/kernel/irq.c +++ b/arch/sh/kernel/irq.c @@ -149,6 +149,7 @@ void irq_ctx_exit(int cpu) hardirq_ctx[cpu] = NULL; } +#ifndef CONFIG_PREEMPT_RT void do_softirq_own_stack(void) { struct thread_info *curctx; @@ -176,6 +177,7 @@ void do_softirq_own_stack(void) "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr" ); } +#endif #else static inline void handle_one_irq(unsigned int irq) { diff --git a/arch/sparc/kernel/irq_64.c b/arch/sparc/kernel/irq_64.c index c8848bb681a1..41fa1be980a3 100644 --- a/arch/sparc/kernel/irq_64.c +++ b/arch/sparc/kernel/irq_64.c @@ -855,6 +855,7 @@ void __irq_entry handler_irq(int pil, struct pt_regs *regs) set_irq_regs(old_regs); } +#ifndef CONFIG_PREEMPT_RT void do_softirq_own_stack(void) { void *orig_sp, *sp = softirq_stack[smp_processor_id()]; @@ -869,6 +870,7 @@ void do_softirq_own_stack(void) __asm__ __volatile__("mov %0, %%sp" : : "r" (orig_sp)); } +#endif #ifdef CONFIG_HOTPLUG_CPU void fixup_irqs(void) |