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-rw-r--r--arch/parisc/kernel/irq.c104
1 files changed, 102 insertions, 2 deletions
diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
index 8094d3ed3b6..e255db0bb76 100644
--- a/arch/parisc/kernel/irq.c
+++ b/arch/parisc/kernel/irq.c
@@ -152,6 +152,39 @@ 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_printf(p, " Kernel stack usage\n");
+#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_printf(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_printf(p, " Function call interrupts\n");
+#endif
+ seq_printf(p, "%*s: ", prec, "TLB");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
+ seq_printf(p, " TLB shootdowns\n");
+ return 0;
+}
+
int show_interrupts(struct seq_file *p, void *v)
{
int i = *(loff_t *) v, j;
@@ -219,6 +252,9 @@ 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 +366,66 @@ static inline int eirr_to_irq(unsigned long eirr)
return (BITS_PER_LONG - bit) + TIMER_IRQ;
}
+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;
+
+ /* 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;
+ last_usage = &per_cpu(irq_stat.kernel_stack_usage, smp_processor_id());
+
+ 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);
+
+ if (sysctl_panic_on_stackoverflow)
+ panic("low stack detected by irq handler - check messages\n");
+#endif
+}
+
+#ifdef CONFIG_IRQSTACKS
+DEFINE_PER_CPU(union irq_stack_union, irq_stack_union);
+
+static void execute_on_irq_stack(void *func, unsigned long param1)
+{
+ unsigned long *irq_stack_start;
+ unsigned long irq_stack;
+ int cpu = smp_processor_id();
+
+ irq_stack_start = &per_cpu(irq_stack_union, cpu).stack[0];
+ irq_stack = (unsigned long) irq_stack_start;
+ irq_stack = ALIGN(irq_stack, 16); /* align for stack frame usage */
+
+ BUG_ON(*irq_stack_start); /* report bug if we were called recursive. */
+ *irq_stack_start = 1;
+
+ /* This is where we switch to the IRQ stack. */
+ call_on_stack(param1, func, irq_stack);
+
+ *irq_stack_start = 0;
+}
+#endif /* CONFIG_IRQSTACKS */
+
/* ONLY called from entry.S:intr_extint() */
void do_cpu_irq_mask(struct pt_regs *regs)
{
@@ -364,7 +460,13 @@ 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 +522,4 @@ void __init init_IRQ(void)
cpu_eiem = EIEM_MASK(TIMER_IRQ);
#endif
set_eiem(cpu_eiem); /* EIEM : enable all external intr */
-
}
-