Re: [RFC][PATCH 06/10] tracing: Add trigger file for trace_markers tracefs/ftrace/print

From: Namhyung Kim
Date: Sun May 13 2018 - 23:13:24 EST


On Fri, May 11, 2018 at 03:49:33PM -0400, Steven Rostedt wrote:
> From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
>
> Allow writing to the trace_markers file initiate triggers defined in
> tracefs/ftrace/print/trigger file. This will allow of user space to trigger
> the same type of triggers (including histograms) that the trace events use.
>
> Cc: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
> Cc: Clark Williams <williams@xxxxxxxxxx>
> Cc: Karim Yaghmour <karim.yaghmour@xxxxxxxxxxx>
> Cc: Brendan Gregg <bgregg@xxxxxxxxxxx>
> Suggested-by: Joel Fernandes <joelaf@xxxxxxxxxx>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> ---

[SNIP]
> diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
> index e3a658bac10f..de3fce14cd00 100644
> --- a/kernel/trace/trace_entries.h
> +++ b/kernel/trace/trace_entries.h
> @@ -230,7 +230,7 @@ FTRACE_ENTRY(bprint, bprint_entry,
> FILTER_OTHER
> );
>
> -FTRACE_ENTRY(print, print_entry,
> +FTRACE_ENTRY_REG(print, print_entry,
>
> TRACE_PRINT,
>
> @@ -242,7 +242,9 @@ FTRACE_ENTRY(print, print_entry,
> F_printk("%ps: %s",
> (void *)__entry->ip, __entry->buf),
>
> - FILTER_OTHER
> + FILTER_OTHER,
> +
> + ftrace_event_register

I wonder this is still needed since you added __find_event_file()
which ignores the reg field. Maybe I'm missing something..

Anyway it looks whitespace damaged.

Thanks,
Namhyung


> );
>
> FTRACE_ENTRY(raw_data, raw_data_entry,
> diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
> index d842f1eadfe5..45630a76ed3a 100644
> --- a/kernel/trace/trace_export.c
> +++ b/kernel/trace/trace_export.c
> @@ -14,6 +14,13 @@
>
> #include "trace_output.h"
>
> +/* Stub function for events with triggers */
> +static int ftrace_event_register(struct trace_event_call *call,
> + enum trace_reg type, void *data)
> +{
> + return 0;
> +}
> +
> #undef TRACE_SYSTEM
> #define TRACE_SYSTEM ftrace
>
> --
> 2.17.0
>
>