diff options
Diffstat (limited to 'arch/parisc/kernel/irq.c')
| -rw-r--r-- | arch/parisc/kernel/irq.c | 198 |
1 files changed, 195 insertions, 3 deletions
diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c index 8094d3ed3b64..2e6443b1e922 100644 --- a/arch/parisc/kernel/irq.c +++ b/arch/parisc/kernel/irq.c @@ -27,11 +27,11 @@ #include <linux/interrupt.h> #include <linux/kernel_stat.h> #include <linux/seq_file.h> -#include <linux/spinlock.h> #include <linux/types.h> #include <asm/io.h> #include <asm/smp.h> +#include <asm/ldcw.h> #undef PARISC_IRQ_CR16_COUNTS @@ -152,6 +152,53 @@ static struct irq_chip cpu_interrupt_type = { .irq_retrigger = NULL, }; +DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat); +#define irq_stats(x) (&per_cpu(irq_stat, x)) + +/* + * /proc/interrupts printing for arch specific interrupts + */ +int arch_show_interrupts(struct seq_file *p, int prec) +{ + int j; + +#ifdef CONFIG_DEBUG_STACKOVERFLOW + seq_printf(p, "%*s: ", prec, "STK"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->kernel_stack_usage); + seq_puts(p, " Kernel stack usage\n"); +# ifdef CONFIG_IRQSTACKS + seq_printf(p, "%*s: ", prec, "IST"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_stack_usage); + seq_puts(p, " Interrupt stack usage\n"); +# endif +#endif +#ifdef CONFIG_SMP + seq_printf(p, "%*s: ", prec, "RES"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count); + seq_puts(p, " Rescheduling interrupts\n"); + seq_printf(p, "%*s: ", prec, "CAL"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_call_count); + seq_puts(p, " Function call interrupts\n"); +#endif + seq_printf(p, "%*s: ", prec, "UAH"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_unaligned_count); + seq_puts(p, " Unaligned access handler traps\n"); + seq_printf(p, "%*s: ", prec, "FPA"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_fpassist_count); + seq_puts(p, " Floating point assist traps\n"); + seq_printf(p, "%*s: ", prec, "TLB"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count); + seq_puts(p, " TLB shootdowns\n"); + return 0; +} + int show_interrupts(struct seq_file *p, void *v) { int i = *(loff_t *) v, j; @@ -219,6 +266,9 @@ int show_interrupts(struct seq_file *p, void *v) raw_spin_unlock_irqrestore(&desc->lock, flags); } + if (i == NR_IRQS) + arch_show_interrupts(p, 3); + return 0; } @@ -330,6 +380,144 @@ static inline int eirr_to_irq(unsigned long eirr) return (BITS_PER_LONG - bit) + TIMER_IRQ; } +#ifdef CONFIG_IRQSTACKS +/* + * IRQ STACK - used for irq handler + */ +#define IRQ_STACK_SIZE (4096 << 2) /* 16k irq stack size */ + +union irq_stack_union { + unsigned long stack[IRQ_STACK_SIZE/sizeof(unsigned long)]; + volatile unsigned int slock[4]; + volatile unsigned int lock[1]; +}; + +DEFINE_PER_CPU(union irq_stack_union, irq_stack_union) = { + .slock = { 1,1,1,1 }, + }; +#endif + + +int sysctl_panic_on_stackoverflow = 1; + +static inline void stack_overflow_check(struct pt_regs *regs) +{ +#ifdef CONFIG_DEBUG_STACKOVERFLOW + #define STACK_MARGIN (256*6) + + /* Our stack starts directly behind the thread_info struct. */ + unsigned long stack_start = (unsigned long) current_thread_info(); + unsigned long sp = regs->gr[30]; + unsigned long stack_usage; + unsigned int *last_usage; + int cpu = smp_processor_id(); + + /* if sr7 != 0, we interrupted a userspace process which we do not want + * to check for stack overflow. We will only check the kernel stack. */ + if (regs->sr[7]) + return; + + /* calculate kernel stack usage */ + stack_usage = sp - stack_start; +#ifdef CONFIG_IRQSTACKS + if (likely(stack_usage <= THREAD_SIZE)) + goto check_kernel_stack; /* found kernel stack */ + + /* check irq stack usage */ + stack_start = (unsigned long) &per_cpu(irq_stack_union, cpu).stack; + stack_usage = sp - stack_start; + + last_usage = &per_cpu(irq_stat.irq_stack_usage, cpu); + if (unlikely(stack_usage > *last_usage)) + *last_usage = stack_usage; + + if (likely(stack_usage < (IRQ_STACK_SIZE - STACK_MARGIN))) + return; + + pr_emerg("stackcheck: %s will most likely overflow irq stack " + "(sp:%lx, stk bottom-top:%lx-%lx)\n", + current->comm, sp, stack_start, stack_start + IRQ_STACK_SIZE); + goto panic_check; + +check_kernel_stack: +#endif + + /* check kernel stack usage */ + last_usage = &per_cpu(irq_stat.kernel_stack_usage, cpu); + + if (unlikely(stack_usage > *last_usage)) + *last_usage = stack_usage; + + if (likely(stack_usage < (THREAD_SIZE - STACK_MARGIN))) + return; + + pr_emerg("stackcheck: %s will most likely overflow kernel stack " + "(sp:%lx, stk bottom-top:%lx-%lx)\n", + current->comm, sp, stack_start, stack_start + THREAD_SIZE); + +#ifdef CONFIG_IRQSTACKS +panic_check: +#endif + if (sysctl_panic_on_stackoverflow) + panic("low stack detected by irq handler - check messages\n"); +#endif +} + +#ifdef CONFIG_IRQSTACKS +/* in entry.S: */ +void call_on_stack(unsigned long p1, void *func, unsigned long new_stack); + +static void execute_on_irq_stack(void *func, unsigned long param1) +{ + union irq_stack_union *union_ptr; + unsigned long irq_stack; + volatile unsigned int *irq_stack_in_use; + + union_ptr = &per_cpu(irq_stack_union, smp_processor_id()); + irq_stack = (unsigned long) &union_ptr->stack; + irq_stack = ALIGN(irq_stack + sizeof(irq_stack_union.slock), + 64); /* align for stack frame usage */ + + /* We may be called recursive. If we are already using the irq stack, + * just continue to use it. Use spinlocks to serialize + * the irq stack usage. + */ + irq_stack_in_use = (volatile unsigned int *)__ldcw_align(union_ptr); + if (!__ldcw(irq_stack_in_use)) { + void (*direct_call)(unsigned long p1) = func; + + /* We are using the IRQ stack already. + * Do direct call on current stack. */ + direct_call(param1); + return; + } + + /* This is where we switch to the IRQ stack. */ + call_on_stack(param1, func, irq_stack); + + /* free up irq stack usage. */ + *irq_stack_in_use = 1; +} + +asmlinkage void do_softirq(void) +{ + __u32 pending; + unsigned long flags; + + if (in_interrupt()) + return; + + local_irq_save(flags); + + pending = local_softirq_pending(); + + if (pending) + execute_on_irq_stack(__do_softirq, 0); + + local_irq_restore(flags); +} +#endif /* CONFIG_IRQSTACKS */ + /* ONLY called from entry.S:intr_extint() */ void do_cpu_irq_mask(struct pt_regs *regs) { @@ -364,7 +552,13 @@ void do_cpu_irq_mask(struct pt_regs *regs) goto set_out; } #endif + stack_overflow_check(regs); + +#ifdef CONFIG_IRQSTACKS + execute_on_irq_stack(&generic_handle_irq, irq); +#else generic_handle_irq(irq); +#endif /* CONFIG_IRQSTACKS */ out: irq_exit(); @@ -420,6 +614,4 @@ void __init init_IRQ(void) cpu_eiem = EIEM_MASK(TIMER_IRQ); #endif set_eiem(cpu_eiem); /* EIEM : enable all external intr */ - } - |