parisc: more irq statistics in /proc/interrupts

Add framework and initial values for more fine grained statistics in
/proc/interrupts.

Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/arch/parisc/include/asm/hardirq.h b/arch/parisc/include/asm/hardirq.h
index 0d68184a76cb54006aeb5142c54315564eabd7aa..a9c0fb195253ec78d650e9be684a7bb567e619e5 100644 (file)
--- a/arch/parisc/include/asm/hardirq.h
+++ b/arch/parisc/include/asm/hardirq.h
@@ -1,11 +1,45 @@
 /* hardirq.h: PA-RISC hard IRQ support.
  *
  * Copyright (C) 2001 Matthew Wilcox <matthew@wil.cx>
+ * Copyright (C) 2013 Helge Deller <deller@gmx.de>
  */
 
 #ifndef _PARISC_HARDIRQ_H
 #define _PARISC_HARDIRQ_H
 
-#include <asm-generic/hardirq.h>
+#include <linux/cache.h>
+#include <linux/threads.h>
+#include <linux/irq.h>
+
+typedef struct {
+       unsigned int __softirq_pending;
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+       unsigned int kernel_stack_usage;
+#endif
+#ifdef CONFIG_SMP
+       unsigned int irq_resched_count;
+       unsigned int irq_call_count;
+       /*
+        * irq_tlb_count is double-counted in irq_call_count, so it must be
+        * subtracted from irq_call_count when displaying irq_call_count
+        */
+       unsigned int irq_tlb_count;
+#endif
+} ____cacheline_aligned irq_cpustat_t;
+
+DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
+
+#define __ARCH_IRQ_STAT
+#define __IRQ_STAT(cpu, member) (irq_stat[cpu].member)
+#define inc_irq_stat(member)   this_cpu_inc(irq_stat.member)
+#define local_softirq_pending()        this_cpu_read(irq_stat.__softirq_pending)
+
+#define __ARCH_SET_SOFTIRQ_PENDING
+
+#define set_softirq_pending(x) \
+               this_cpu_write(irq_stat.__softirq_pending, (x))
+#define or_softirq_pending(x)  this_cpu_or(irq_stat.__softirq_pending, (x))
+
+#define ack_bad_irq(irq) WARN(1, "unexpected IRQ trap at vector %02x\n", irq)
 
 #endif /* _PARISC_HARDIRQ_H */

diff --git a/arch/parisc/include/asm/processor.h b/arch/parisc/include/asm/processor.h
index 242f06a5fbd8746587ae018513e8c6c258632047..064015547d1e32be0a968ba946bc54f8db362895 100644 (file)
--- a/arch/parisc/include/asm/processor.h
+++ b/arch/parisc/include/asm/processor.h
@@ -112,7 +112,6 @@ struct cpuinfo_parisc {
        unsigned long txn_addr;     /* MMIO addr of EIR or id_eid */
 #ifdef CONFIG_SMP
        unsigned long pending_ipi;  /* bitmap of type ipi_message_type */
-       unsigned long ipi_count;    /* number ipi Interrupts */
 #endif
        unsigned long bh_count;     /* number of times bh was invoked */
        unsigned long prof_counter; /* per CPU profiling support */

diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
index 810f9cf89e4860255b2e882fb1d6e0763d523eb6..a237e32ede190a83641383a2d6248f14f7e97c92 100644 (file)
--- a/arch/parisc/kernel/irq.c
+++ b/arch/parisc/kernel/irq.c
@@ -152,6 +152,40 @@ 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 -
+                                       irq_stats(j)->irq_tlb_count);
+       seq_printf(p, "  Function call interrupts\n");
+       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");
+#endif
+       return 0;
+}
+
 int show_interrupts(struct seq_file *p, void *v)
 {
        int i = *(loff_t *) v, j;
@@ -219,6 +253,9 @@ 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;
 }
 
@@ -340,13 +377,22 @@ static inline void stack_overflow_check(struct pt_regs *regs)
        /* 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;
 
-       if (likely((sp - stack_start) < (THREAD_SIZE - STACK_MARGIN)))
+       /* 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 "

diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c
index fd1bb1519c2b114be60f3d75089b7d81f29adbd7..218e20bff9d20eceb66db3943375c92c711ae62a 100644 (file)
--- a/arch/parisc/kernel/smp.c
+++ b/arch/parisc/kernel/smp.c
@@ -127,7 +127,7 @@ ipi_interrupt(int irq, void *dev_id)
        unsigned long flags;
 
        /* Count this now; we may make a call that never returns. */
-       p->ipi_count++;
+       inc_irq_stat(irq_call_count);
 
        mb();   /* Order interrupt and bit testing. */
 
@@ -155,6 +155,7 @@ ipi_interrupt(int irq, void *dev_id)
                                
                        case IPI_RESCHEDULE:
                                smp_debug(100, KERN_DEBUG "CPU%d IPI_RESCHEDULE\n", this_cpu);
+                               inc_irq_stat(irq_resched_count);
                                scheduler_ipi();
                                break;
 

diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 157b931e7b09b89b60790b60aa016e5f5ac12913..ce939ac8622b84b7278f9e979e68a56354267adf 100644 (file)
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -1069,6 +1069,7 @@ void flush_tlb_all(void)
 {
        int do_recycle;
 
+       inc_irq_stat(irq_tlb_count);
        do_recycle = 0;
        spin_lock(&sid_lock);
        if (dirty_space_ids > RECYCLE_THRESHOLD) {
@@ -1089,6 +1090,7 @@ void flush_tlb_all(void)
 #else
 void flush_tlb_all(void)
 {
+       inc_irq_stat(irq_tlb_count);
        spin_lock(&sid_lock);
        flush_tlb_all_local(NULL);
        recycle_sids();