0231022cc3
Impact: help to find the better depth of trace We decided to arbitrary define the depth of function return trace as "20". Perhaps this is not enough. To help finding an optimal depth, we measure now the overrun: the number of functions that have been missed for the current thread. By default this is not displayed, we have to do set a particular flag on the return tracer: echo overrun > /debug/tracing/trace_options And the overrun will be printed on the right. As the trace shows below, the current 20 depth is not enough. update_wall_time+0x37f/0x8c0 -> update_xtime_cache (345 ns) (Overruns: 2838) update_wall_time+0x384/0x8c0 -> clocksource_get_next (1141 ns) (Overruns: 2838) do_timer+0x23/0x100 -> update_wall_time (3882 ns) (Overruns: 2838) tick_do_update_jiffies64+0xbf/0x160 -> do_timer (5339 ns) (Overruns: 2838) tick_sched_timer+0x6a/0xf0 -> tick_do_update_jiffies64 (7209 ns) (Overruns: 2838) vgacon_set_cursor_size+0x98/0x120 -> native_io_delay (2613 ns) (Overruns: 274) vgacon_cursor+0x16e/0x1d0 -> vgacon_set_cursor_size (33151 ns) (Overruns: 274) set_cursor+0x5f/0x80 -> vgacon_cursor (36432 ns) (Overruns: 274) con_flush_chars+0x34/0x40 -> set_cursor (38790 ns) (Overruns: 274) release_console_sem+0x1ec/0x230 -> up (721 ns) (Overruns: 274) release_console_sem+0x225/0x230 -> wake_up_klogd (316 ns) (Overruns: 274) con_flush_chars+0x39/0x40 -> release_console_sem (2996 ns) (Overruns: 274) con_write+0x22/0x30 -> con_flush_chars (46067 ns) (Overruns: 274) n_tty_write+0x1cc/0x360 -> con_write (292670 ns) (Overruns: 274) smp_apic_timer_interrupt+0x2a/0x90 -> native_apic_mem_write (330 ns) (Overruns: 274) irq_enter+0x17/0x70 -> idle_cpu (413 ns) (Overruns: 274) smp_apic_timer_interrupt+0x2f/0x90 -> irq_enter (1525 ns) (Overruns: 274) ktime_get_ts+0x40/0x70 -> getnstimeofday (465 ns) (Overruns: 274) ktime_get_ts+0x60/0x70 -> set_normalized_timespec (436 ns) (Overruns: 274) ktime_get+0x16/0x30 -> ktime_get_ts (2501 ns) (Overruns: 274) hrtimer_interrupt+0x77/0x1a0 -> ktime_get (3439 ns) (Overruns: 274) Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> |
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| bigsmp | ||
| es7000 | ||
| mach-default | ||
| mach-generic | ||
| mach-rdc321x | ||
| mach-voyager | ||
| numaq | ||
| summit | ||
| uv | ||
| visws | ||
| xen | ||
| a.out-core.h | ||
| a.out.h | ||
| acpi.h | ||
| agp.h | ||
| alternative-asm.h | ||
| alternative.h | ||
| amd_iommu_types.h | ||
| amd_iommu.h | ||
| apic.h | ||
| apicdef.h | ||
| arch_hooks.h | ||
| asm.h | ||
| atomic_32.h | ||
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| atomic.h | ||
| auxvec.h | ||
| bios_ebda.h | ||
| bitops.h | ||
| boot.h | ||
| bootparam.h | ||
| bug.h | ||
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| byteorder.h | ||
| cache.h | ||
| cacheflush.h | ||
| calgary.h | ||
| calling.h | ||
| checksum_32.h | ||
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| checksum.h | ||
| cmpxchg_32.h | ||
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| compat.h | ||
| cpu.h | ||
| cpufeature.h | ||
| cputime.h | ||
| current.h | ||
| debugreg.h | ||
| delay.h | ||
| desc_defs.h | ||
| desc.h | ||
| device.h | ||
| div64.h | ||
| dma-mapping.h | ||
| dma.h | ||
| dmi.h | ||
| ds.h | ||
| dwarf2.h | ||
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| elf.h | ||
| emergency-restart.h | ||
| errno.h | ||
| fb.h | ||
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| fixmap_32.h | ||
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| floppy.h | ||
| frame.h | ||
| ftrace.h | ||
| futex.h | ||
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| genapic_32.h | ||
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| hardirq_32.h | ||
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| highmem.h | ||
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| hugetlb.h | ||
| hw_irq.h | ||
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| idle.h | ||
| intel_arch_perfmon.h | ||
| io_32.h | ||
| io_64.h | ||
| io_apic.h | ||
| io.h | ||
| ioctl.h | ||
| ioctls.h | ||
| iommu.h | ||
| ipcbuf.h | ||
| ipi.h | ||
| irq_regs_32.h | ||
| irq_regs_64.h | ||
| irq_regs.h | ||
| irq_remapping.h | ||
| irq_vectors.h | ||
| irq.h | ||
| irqflags.h | ||
| ist.h | ||
| k8.h | ||
| Kbuild | ||
| kdebug.h | ||
| kexec.h | ||
| kgdb.h | ||
| kmap_types.h | ||
| kprobes.h | ||
| kvm_host.h | ||
| kvm_para.h | ||
| kvm_x86_emulate.h | ||
| kvm.h | ||
| ldt.h | ||
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| linkage.h | ||
| local.h | ||
| math_emu.h | ||
| mc146818rtc.h | ||
| mca_dma.h | ||
| mca.h | ||
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| microcode.h | ||
| mman.h | ||
| mmconfig.h | ||
| mmu_context_32.h | ||
| mmu_context_64.h | ||
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| mmu.h | ||
| mmx.h | ||
| mmzone_32.h | ||
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| mmzone.h | ||
| module.h | ||
| mpspec_def.h | ||
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| msgbuf.h | ||
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| msr.h | ||
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| numaq.h | ||
| olpc.h | ||
| page_32.h | ||
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| page.h | ||
| param.h | ||
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| pat.h | ||
| pci_32.h | ||
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| pci-direct.h | ||
| pci.h | ||
| pda.h | ||
| percpu.h | ||
| pgalloc.h | ||
| pgtable_32.h | ||
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| pgtable-2level-defs.h | ||
| pgtable-2level.h | ||
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| pgtable-3level.h | ||
| pgtable.h | ||
| poll.h | ||
| posix_types_32.h | ||
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| posix_types.h | ||
| prctl.h | ||
| processor-cyrix.h | ||
| processor-flags.h | ||
| processor.h | ||
| proto.h | ||
| ptrace-abi.h | ||
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| pvclock-abi.h | ||
| pvclock.h | ||
| reboot_fixups.h | ||
| reboot.h | ||
| required-features.h | ||
| resource.h | ||
| resume-trace.h | ||
| rio.h | ||
| rtc.h | ||
| rwlock.h | ||
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| scatterlist.h | ||
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| sections.h | ||
| segment.h | ||
| sembuf.h | ||
| serial.h | ||
| setup.h | ||
| shmbuf.h | ||
| shmparam.h | ||
| sigcontext32.h | ||
| sigcontext.h | ||
| siginfo.h | ||
| signal.h | ||
| smp.h | ||
| socket.h | ||
| sockios.h | ||
| sparsemem.h | ||
| spinlock_types.h | ||
| spinlock.h | ||
| srat.h | ||
| stacktrace.h | ||
| stat.h | ||
| statfs.h | ||
| string_32.h | ||
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| string.h | ||
| suspend_32.h | ||
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| suspend.h | ||
| swiotlb.h | ||
| sync_bitops.h | ||
| syscall.h | ||
| syscalls.h | ||
| system_64.h | ||
| system.h | ||
| tce.h | ||
| termbits.h | ||
| termios.h | ||
| therm_throt.h | ||
| thread_info.h | ||
| time.h | ||
| timer.h | ||
| timex.h | ||
| tlb.h | ||
| tlbflush.h | ||
| topology.h | ||
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| traps.h | ||
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| types.h | ||
| uaccess_32.h | ||
| uaccess_64.h | ||
| uaccess.h | ||
| ucontext.h | ||
| unaligned.h | ||
| unistd_32.h | ||
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| unistd.h | ||
| unwind.h | ||
| user32.h | ||
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| vic.h | ||
| vm86.h | ||
| vmi_time.h | ||
| vmi.h | ||
| voyager.h | ||
| vsyscall.h | ||
| xcr.h | ||
| xor_32.h | ||
| xor_64.h | ||
| xor.h | ||
| xsave.h | ||