Hi Takashi, >> The recent kernel puts the xrun debug messages in trace buffer instead >> of the kernel messages. Try to enable the tracing in >> /sys/kernel/debug/tracing/events/snd_pcm/xrun/enable, and watch the >> trace buffer (/sys/kernel/debug/tracing/trace). > > Thanks for your very quick reply, I'll try this now. I must do this wrong again. So I kept echo 5 > /proc/asound/card2/pcm0p/xrun_debug (not sure if still relevant with ftrace) And I mounted tracefs mount -t tracefs nodev /sys/kernel/tracing And then I can echo 1 > /sys/kernel/tracing/events/snd_pcm/xrun/enable I can verify that cat /sys/kernel/tracing/events/snd_pcm/xrun/enable gives 1 and all enable upper returns X cat /sys/kernel/tracing/tracing_on is 1 But then cat /sys/kernel/tracing/trace Starts with # tracer: nop and then the header for tracing, and that doesn't change over time. No event gets logged. Is tracer "nop" the right one? As for my kernel configuration I have currently, regarding what seems to be related to FTRACE : CONFIG_NOP_TRACER=y CONFIG_HAVE_FUNCTION_TRACER=y CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y CONFIG_HAVE_DYNAMIC_FTRACE=y CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS=y CONFIG_HAVE_FTRACE_MCOUNT_RECORD=y CONFIG_HAVE_SYSCALL_TRACEPOINTS=y CONFIG_HAVE_FENTRY=y CONFIG_HAVE_C_RECORDMCOUNT=y CONFIG_TRACE_CLOCK=y CONFIG_RING_BUFFER=y CONFIG_EVENT_TRACING=y CONFIG_CONTEXT_SWITCH_TRACER=y CONFIG_TRACING=y CONFIG_GENERIC_TRACER=y CONFIG_TRACING_SUPPORT=y CONFIG_FTRACE=y # CONFIG_FUNCTION_TRACER is not set # CONFIG_PREEMPTIRQ_EVENTS is not set # CONFIG_IRQSOFF_TRACER is not set # CONFIG_SCHED_TRACER is not set # CONFIG_HWLAT_TRACER is not set # CONFIG_FTRACE_SYSCALLS is not set # CONFIG_TRACER_SNAPSHOT is not set I guess I might need to enable one of the config like FUNCTION_TRACER? Sorry, I just started Linux, so my knowledge of it is very low. Thanks, Raphael _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
