Messages in this thread Patch in this message | | | Subject | Re: [PATCH]trace,x86: add x86 irq vector tracepoints | From | Steven Rostedt <> | Date | Thu, 05 Jul 2012 16:44:13 -0400 |
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Thomas Gleixner is the unofficial (or is it now official?) maintainer of interrupts. You need his Ack for this change.
-- Steve
On Tue, 2012-07-03 at 22:29 +0000, Seiji Aguchi wrote: > As Vaibhav explained in the thread below, tracepoints for irq vectors > is useful. > > http://www.spinics.net/lists/mm-commits/msg85707.html > > <snip> > The current interrupt traces from irq_handler_entry and irq_handler_exit > provide when an interrupt is handled. They provide good data about when > the system has switched to kernel space and how it affects the currently > running processes. > > There are some IRQ vectors which trigger the system into kernel space, > which are not handled in generic IRQ handlers. Tracing such events gives > us the information about IRQ interaction with other system events. > > The trace also tells where the system is spending its time. We want to > know which cores are handling interrupts and how they are affecting other > processes in the system. Also, the trace provides information about when > the cores are idle and which interrupts are changing that state. > <snip> > > On the other hand, my usecase is tracing just local timer event and > getting a value of instruction pointer. > > I suggested to add an argument local timer event to get instruction pointer before. > But there is another way to get it with external module like systemtap. > So, I don't need to add any argument to irq vector tracepoints now. > > Vaibhav's patch shared a trace point ,irq_vector_entry/irq_vector_exit, in all events. > But there is an above use case to trace specific irq_vector rather than tracing all events. > In this case, we are concerned about overhead due to unwanted events. > > To reduce the overhead, this patch modifies Vaibhav's one to enable each event independently. > > Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> > Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> > > --- > arch/x86/kernel/apic/apic.c | 7 + > arch/x86/kernel/cpu/mcheck/therm_throt.c | 3 + > arch/x86/kernel/cpu/mcheck/threshold.c | 3 + > arch/x86/kernel/irq.c | 5 + > arch/x86/kernel/irq_work.c | 3 + > arch/x86/kernel/nmi.c | 3 + > arch/x86/kernel/smp.c | 7 + > arch/x86/mm/tlb.c | 3 + > include/trace/events/irq_vectors.h | 288 ++++++++++++++++++++++++++++++ > 9 files changed, 322 insertions(+), 0 deletions(-) > create mode 100644 include/trace/events/irq_vectors.h > > diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c > index 39a222e..db219c9 100644 > --- a/arch/x86/kernel/apic/apic.c > +++ b/arch/x86/kernel/apic/apic.c > @@ -34,6 +34,7 @@ > #include <linux/dmi.h> > #include <linux/smp.h> > #include <linux/mm.h> > +#include <trace/events/irq_vectors.h> > > #include <asm/irq_remapping.h> > #include <asm/perf_event.h> > @@ -895,7 +896,9 @@ void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs) > */ > irq_enter(); > exit_idle(); > + trace_local_timer_entry(LOCAL_TIMER_VECTOR); > local_apic_timer_interrupt(); > + trace_local_timer_exit(LOCAL_TIMER_VECTOR); > irq_exit(); > > set_irq_regs(old_regs); > @@ -1881,6 +1884,7 @@ void smp_spurious_interrupt(struct pt_regs *regs) > > irq_enter(); > exit_idle(); > + trace_spurious_apic_entry(SPURIOUS_APIC_VECTOR); > /* > * Check if this really is a spurious interrupt and ACK it > * if it is a vectored one. Just in case... > @@ -1895,6 +1899,7 @@ void smp_spurious_interrupt(struct pt_regs *regs) > /* see sw-dev-man vol 3, chapter 7.4.13.5 */ > pr_info("spurious APIC interrupt on CPU#%d, " > "should never happen.\n", smp_processor_id()); > + trace_spurious_apic_exit(SPURIOUS_APIC_VECTOR); > irq_exit(); > } > > @@ -1918,6 +1923,7 @@ void smp_error_interrupt(struct pt_regs *regs) > > irq_enter(); > exit_idle(); > + trace_error_apic_entry(ERROR_APIC_VECTOR); > /* First tickle the hardware, only then report what went on. -- REW */ > v0 = apic_read(APIC_ESR); > apic_write(APIC_ESR, 0); > @@ -1938,6 +1944,7 @@ void smp_error_interrupt(struct pt_regs *regs) > > apic_printk(APIC_DEBUG, KERN_CONT "\n"); > > + trace_error_apic_exit(ERROR_APIC_VECTOR); > irq_exit(); > } > > diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c > index 47a1870..79cc87a 100644 > --- a/arch/x86/kernel/cpu/mcheck/therm_throt.c > +++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c > @@ -23,6 +23,7 @@ > #include <linux/init.h> > #include <linux/smp.h> > #include <linux/cpu.h> > +#include <trace/events/irq_vectors.h> > > #include <asm/processor.h> > #include <asm/apic.h> > @@ -382,8 +383,10 @@ asmlinkage void smp_thermal_interrupt(struct pt_regs *regs) > { > irq_enter(); > exit_idle(); > + trace_thermal_apic_entry(THERMAL_APIC_VECTOR); > inc_irq_stat(irq_thermal_count); > smp_thermal_vector(); > + trace_thermal_apic_exit(THERMAL_APIC_VECTOR); > irq_exit(); > /* Ack only at the end to avoid potential reentry */ > ack_APIC_irq(); > diff --git a/arch/x86/kernel/cpu/mcheck/threshold.c b/arch/x86/kernel/cpu/mcheck/threshold.c > index aa578ca..45f33a3 100644 > --- a/arch/x86/kernel/cpu/mcheck/threshold.c > +++ b/arch/x86/kernel/cpu/mcheck/threshold.c > @@ -3,6 +3,7 @@ > */ > #include <linux/interrupt.h> > #include <linux/kernel.h> > +#include <trace/events/irq_vectors.h> > > #include <asm/irq_vectors.h> > #include <asm/apic.h> > @@ -21,8 +22,10 @@ asmlinkage void smp_threshold_interrupt(void) > { > irq_enter(); > exit_idle(); > + trace_threshold_apic_entry(THRESHOLD_APIC_VECTOR); > inc_irq_stat(irq_threshold_count); > mce_threshold_vector(); > + trace_threshold_apic_exit(THRESHOLD_APIC_VECTOR); > irq_exit(); > /* Ack only at the end to avoid potential reentry */ > ack_APIC_irq(); > diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c > index 3dafc60..e6786a1 100644 > --- a/arch/x86/kernel/irq.c > +++ b/arch/x86/kernel/irq.c > @@ -18,6 +18,9 @@ > #include <asm/mce.h> > #include <asm/hw_irq.h> > > +#define CREATE_TRACE_POINTS > +#include <trace/events/irq_vectors.h> > + > atomic_t irq_err_count; > > /* Function pointer for generic interrupt vector handling */ > @@ -218,11 +221,13 @@ void smp_x86_platform_ipi(struct pt_regs *regs) > > exit_idle(); > > + trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR); > inc_irq_stat(x86_platform_ipis); > > if (x86_platform_ipi_callback) > x86_platform_ipi_callback(); > > + trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR); > irq_exit(); > > set_irq_regs(old_regs); > diff --git a/arch/x86/kernel/irq_work.c b/arch/x86/kernel/irq_work.c > index ca8f703..2cf7505 100644 > --- a/arch/x86/kernel/irq_work.c > +++ b/arch/x86/kernel/irq_work.c > @@ -8,13 +8,16 @@ > #include <linux/irq_work.h> > #include <linux/hardirq.h> > #include <asm/apic.h> > +#include <trace/events/irq_vectors.h> > > void smp_irq_work_interrupt(struct pt_regs *regs) > { > irq_enter(); > ack_APIC_irq(); > + trace_irq_work_entry(IRQ_WORK_VECTOR); > inc_irq_stat(apic_irq_work_irqs); > irq_work_run(); > + trace_irq_work_exit(IRQ_WORK_VECTOR); > irq_exit(); > } > > diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c > index a0b2f84..84e8102 100644 > --- a/arch/x86/kernel/nmi.c > +++ b/arch/x86/kernel/nmi.c > @@ -28,6 +28,7 @@ > #include <asm/mach_traps.h> > #include <asm/nmi.h> > #include <asm/x86_init.h> > +#include <trace/events/irq_vectors.h> > > struct nmi_desc { > spinlock_t lock; > @@ -463,12 +464,14 @@ do_nmi(struct pt_regs *regs, long error_code) > nmi_nesting_preprocess(regs); > > nmi_enter(); > + trace_nmi_entry(NMI_VECTOR); > > inc_irq_stat(__nmi_count); > > if (!ignore_nmis) > default_do_nmi(regs); > > + trace_nmi_exit(NMI_VECTOR); > nmi_exit(); > > /* On i386, may loop back to preprocess */ > diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c > index 48d2b7d..5b2d6de 100644 > --- a/arch/x86/kernel/smp.c > +++ b/arch/x86/kernel/smp.c > @@ -23,6 +23,7 @@ > #include <linux/interrupt.h> > #include <linux/cpu.h> > #include <linux/gfp.h> > +#include <trace/events/irq_vectors.h> > > #include <asm/mtrr.h> > #include <asm/tlbflush.h> > @@ -252,8 +253,10 @@ finish: > void smp_reschedule_interrupt(struct pt_regs *regs) > { > ack_APIC_irq(); > + trace_reschedule_entry(RESCHEDULE_VECTOR); > inc_irq_stat(irq_resched_count); > scheduler_ipi(); > + trace_reschedule_exit(RESCHEDULE_VECTOR); > /* > * KVM uses this interrupt to force a cpu out of guest mode > */ > @@ -263,8 +266,10 @@ void smp_call_function_interrupt(struct pt_regs *regs) > { > ack_APIC_irq(); > irq_enter(); > + trace_call_function_entry(CALL_FUNCTION_VECTOR); > generic_smp_call_function_interrupt(); > inc_irq_stat(irq_call_count); > + trace_call_function_exit(CALL_FUNCTION_VECTOR); > irq_exit(); > } > > @@ -272,8 +277,10 @@ void smp_call_function_single_interrupt(struct pt_regs *regs) > { > ack_APIC_irq(); > irq_enter(); > + trace_call_function_single_entry(CALL_FUNCTION_SINGLE_VECTOR); > generic_smp_call_function_single_interrupt(); > inc_irq_stat(irq_call_count); > + trace_call_function_single_exit(CALL_FUNCTION_SINGLE_VECTOR); > irq_exit(); > } > > diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c > index 5e57e11..8a66e91 100644 > --- a/arch/x86/mm/tlb.c > +++ b/arch/x86/mm/tlb.c > @@ -5,6 +5,7 @@ > #include <linux/smp.h> > #include <linux/interrupt.h> > #include <linux/module.h> > +#include <trace/events/irq_vectors.h> > #include <linux/cpu.h> > > #include <asm/tlbflush.h> > @@ -143,6 +144,7 @@ void smp_invalidate_interrupt(struct pt_regs *regs) > sender = ~regs->orig_ax - INVALIDATE_TLB_VECTOR_START; > f = &flush_state[sender]; > > + trace_invalidate_tlb_entry(INVALIDATE_TLB_VECTOR_START + sender); > if (!cpumask_test_cpu(cpu, to_cpumask(f->flush_cpumask))) > goto out; > /* > @@ -169,6 +171,7 @@ out: > cpumask_clear_cpu(cpu, to_cpumask(f->flush_cpumask)); > smp_mb__after_clear_bit(); > inc_irq_stat(irq_tlb_count); > + trace_invalidate_tlb_exit(INVALIDATE_TLB_VECTOR_START + sender); > } > > static void flush_tlb_others_ipi(const struct cpumask *cpumask, > diff --git a/include/trace/events/irq_vectors.h b/include/trace/events/irq_vectors.h > new file mode 100644 > index 0000000..4c1cb4e > --- /dev/null > +++ b/include/trace/events/irq_vectors.h > @@ -0,0 +1,288 @@ > +#undef TRACE_SYSTEM > +#define TRACE_SYSTEM irq_vectors > + > +#if !defined(_TRACE_IRQ_VECTORS_H) || defined(TRACE_HEADER_MULTI_READ) > +#define _TRACE_IRQ_VECTORS_H > + > +#include <linux/tracepoint.h> > +#include <asm/irq.h> > + > +DECLARE_EVENT_CLASS(irq_vector, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq), > + > + TP_STRUCT__entry( > + __field( int, irq ) > + ), > + > + TP_fast_assign( > + __entry->irq = irq; > + ), > + > + TP_printk("irq=%d", __entry->irq) > +); > + > +/* > + * nmi_entry - called before enterring a nmi vector handler > + */ > +DEFINE_EVENT(irq_vector, nmi_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * nmi_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, nmi_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * local_timer_entry - called before enterring a local timer interrupt > + * vector handler > + */ > +DEFINE_EVENT(irq_vector, local_timer_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * local_timer_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, local_timer_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * error_apic_entry - called before enterring an error apic vector handler > + */ > +DEFINE_EVENT(irq_vector, error_apic_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * error_apic_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, error_apic_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * reschedule_entry - called before enterring a reschedule vector handler > + */ > +DEFINE_EVENT(irq_vector, reschedule_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * reschedule_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, reschedule_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * call_function_entry - called before enterring a call function > + * vector handler > + */ > +DEFINE_EVENT(irq_vector, call_function_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * call_function_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, call_function_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * call_function_single_entry - called before enterring a call function > + * single vector handler > + */ > +DEFINE_EVENT(irq_vector, call_function_single_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * call_function_single_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, call_function_single_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * thermal_apic_entry - called before enterring a thermal apic vector handler > + */ > +DEFINE_EVENT(irq_vector, thermal_apic_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * thermal_apic_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, thermal_apic_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * threshold_apic_entry - called before enterring a threshold apic > + * vector handler > + */ > +DEFINE_EVENT(irq_vector, threshold_apic_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * threshold_apic_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, threshold_apic_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * spurious_apic_entry - called before enterring a spurious apic vector handler > + */ > +DEFINE_EVENT(irq_vector, spurious_apic_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * spurious_apic_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, spurious_apic_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * irq_work_entry - called before enterring an irq work vector handler > + */ > +DEFINE_EVENT(irq_vector, irq_work_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * irq_work_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, irq_work_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * x86_platform_ipi_entry - called before enterring a x86 platform ipi > + * vector handler > + */ > +DEFINE_EVENT(irq_vector, x86_platform_ipi_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * x86_platform_ipi_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, x86_platform_ipi_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * invalidate_tlb_entry - called before enterring an invalidate tlb > + * vector handler > + */ > +DEFINE_EVENT(irq_vector, invalidate_tlb_entry, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +/* > + * invalidate_tlb_exit - called immediately after the interrupt vector > + * handler returns > + */ > +DEFINE_EVENT(irq_vector, invalidate_tlb_exit, > + > + TP_PROTO(int irq), > + > + TP_ARGS(irq) > +); > + > +#endif /* _TRACE_IRQ_VECTORS_H */ > + > +/* This part must be outside protection */ > +#include <trace/define_trace.h>
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