[linuxkernelnewbies] TRACE_EVENT internals

[Peter Teoh]

http://patchwork.kernel.org/patch/18485/ Comments Ingo Molnar - 2009-04-16 08:39:34 * Steven Rostedt <rost...@goodmis.org> wrote: > From: Steven Rostedt <srost...@redhat.com> > > As events start to become popular, and the new way to add tracing > infrastructure into ftrace, it is important to catch any problems > that might happen with a mistake in the TRACE_EVENT macro. > > This patch introduces a startup self test on the registered trace > events. Note, it can only do a generic test, any type of testing > that needs more involement is needed to be implemented by the > tracepoint creators. > > The test goes down one by one enabling a trace point and running > some random tasks (random in the sense that I just made them up). > Those tasks are creating threads, grabbing mutexes and spinlocks > and using workqueues. > > After testing each event individually, it does the same test after > enabling each system of trace points. Like sched, irq, lockdep. > > Then finally it enables all tracepoints and performs the tasks > again. The output to the console on bootup will look like this > when everything works: > > Running tests on trace events: > Testing event kfree_skb: OK > Testing event kmalloc: OK > Testing event kmem_cache_alloc: OK > Testing event kmalloc_node: OK > Testing event kmem_cache_alloc_node: OK > Testing event kfree: OK > Testing event kmem_cache_free: OK > Testing event irq_handler_exit: OK > Testing event irq_handler_entry: OK > Testing event softirq_entry: OK > Testing event softirq_exit: OK > Testing event lock_acquire: OK > Testing event lock_release: OK > Testing event sched_kthread_stop: OK > Testing event sched_kthread_stop_ret: OK > Testing event sched_wait_task: OK > Testing event sched_wakeup: OK > Testing event sched_wakeup_new: OK > Testing event sched_switch: OK > Testing event sched_migrate_task: OK > Testing event sched_process_free: OK > Testing event sched_process_exit: OK > Testing event sched_process_wait: OK > Testing event sched_process_fork: OK > Testing event sched_signal_send: OK > Running tests on trace event systems: > Testing event system skb: OK > Testing event system kmem: OK > Testing event system irq: OK > Testing event system lockdep: OK > Testing event system sched: OK > Running tests on all trace events: > Testing all events: OK Thanks Steve, really nice! /root/linux-2.6/kernel/trace>grep EXPORT *.c blktrace.c:EXPORT_SYMBOL_GPL(__trace_note_message); blktrace.c:EXPORT_SYMBOL_GPL(blk_trace_remove); blktrace.c:EXPORT_SYMBOL_GPL(blk_trace_setup); blktrace.c:EXPORT_SYMBOL_GPL(blk_trace_startstop); blktrace.c:EXPORT_SYMBOL_GPL(blk_add_driver_data); ring_buffer.c:EXPORT_SYMBOL_GPL(tracing_on); ring_buffer.c:EXPORT_SYMBOL_GPL(tracing_off); ring_buffer.c:EXPORT_SYMBOL_GPL(tracing_is_on); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_event_length); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_event_data); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_time_stamp); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp); ring_buffer.c:EXPORT_SYMBOL_GPL(__ring_buffer_alloc); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_free); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_resize); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_lock_reserve); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_unlock_commit); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_event_discard); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_discard_commit); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_write); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_record_disable); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_record_enable); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_record_disable_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_record_enable_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_entries_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_overrun_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_nmi_dropped_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_commit_overrun_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_entries); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_overruns); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_iter_reset); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_iter_empty); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_peek); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_iter_peek); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_consume); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_read_start); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_read_finish); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_read); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_size); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_reset_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_reset); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_empty); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_empty_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_alloc_read_page); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_free_read_page); ring_buffer.c:EXPORT_SYMBOL_GPL(ring_buffer_read_page); trace_branch.c:EXPORT_SYMBOL(ftrace_likely_update); trace.c:EXPORT_SYMBOL_GPL(filter_current_check_discard); trace.c:EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); trace.c:EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); trace.c:EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); trace.c:EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); trace.c:EXPORT_SYMBOL_GPL(trace_vbprintk); trace.c:EXPORT_SYMBOL_GPL(trace_vprintk); trace_events.c:EXPORT_SYMBOL_GPL(trace_define_field); trace_events_filter.c:EXPORT_SYMBOL_GPL(filter_match_preds); trace_events_filter.c:EXPORT_SYMBOL_GPL(init_preds); trace_irqsoff.c:EXPORT_SYMBOL_GPL(start_critical_timings); trace_irqsoff.c:EXPORT_SYMBOL_GPL(stop_critical_timings); trace_irqsoff.c:EXPORT_SYMBOL(trace_hardirqs_on); trace_irqsoff.c:EXPORT_SYMBOL(trace_hardirqs_off); trace_irqsoff.c:EXPORT_SYMBOL(trace_hardirqs_on_caller); trace_irqsoff.c:EXPORT_SYMBOL(trace_hardirqs_off_caller); trace_output.c:EXPORT_PER_CPU_SYMBOL(ftrace_event_seq); trace_output.c:EXPORT_SYMBOL_GPL(trace_seq_printf); trace_output.c:EXPORT_SYMBOL_GPL(trace_seq_vprintf); trace_output.c:EXPORT_SYMBOL(ftrace_print_flags_seq); trace_output.c:EXPORT_SYMBOL(ftrace_print_symbols_seq); trace_output.c:EXPORT_SYMBOL_GPL(register_ftrace_event); trace_output.c:EXPORT_SYMBOL_GPL(unregister_ftrace_event); trace_printk.c:EXPORT_SYMBOL_GPL(__trace_bprintk); trace_printk.c:EXPORT_SYMBOL_GPL(__ftrace_vbprintk); trace_printk.c:EXPORT_SYMBOL_GPL(__trace_printk); trace_printk.c:EXPORT_SYMBOL_GPL(__ftrace_vprintk);