On Tue, 21 Jul 2020 12:37:33 -0400 Steven Rostedt <[email protected]> wrote:
> On Mon, 20 Jul 2020 10:21:15 +0800 > Tingwei Zhang <[email protected]> wrote: > > > Only function traces can be exported to other destinations currently. > > This patch exports event trace as well. > > > > Signed-off-by: Tingwei Zhang <[email protected]> > > --- > > kernel/trace/trace.c | 24 +++++++++++++----------- > > 1 file changed, 13 insertions(+), 11 deletions(-) > > > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > > index bb62269724d5..aef6330836e2 100644 > > --- a/kernel/trace/trace.c > > +++ b/kernel/trace/trace.c > > @@ -2697,17 +2697,6 @@ int tracepoint_printk_sysctl(struct ctl_table > > *table, int write, > > return ret; > > } > > > > -void trace_event_buffer_commit(struct trace_event_buffer *fbuffer) > > -{ > > - if (static_key_false(&tracepoint_printk_key.key)) > > - output_printk(fbuffer); > > - > > - event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer, > > - fbuffer->event, fbuffer->entry, > > - fbuffer->flags, fbuffer->pc, fbuffer->regs); > > -} > > -EXPORT_SYMBOL_GPL(trace_event_buffer_commit); > > - > > Please move the ftrace_exports routines up, instead of moving the > trace_event_buffer_commit() down. As it fits better where it is (next > to the other buffer_commit code). > > -- Steve > > > > /* > > * Skip 3: > > * > > @@ -2868,6 +2857,19 @@ int unregister_ftrace_export(struct > > trace_export *export) } > > EXPORT_SYMBOL_GPL(unregister_ftrace_export); > > > > +void trace_event_buffer_commit(struct trace_event_buffer *fbuffer) > > +{ > > + if (static_key_false(&tracepoint_printk_key.key)) > > + output_printk(fbuffer); > > + > > + if (static_branch_unlikely(&ftrace_exports_enabled)) > > + ftrace_exports(fbuffer->event); I would also recommend making each static branch a separate variable. That way you could pick and choose what you want to enable. If you only want events, and functions are being traced, it will add a bit of overhead to handle the functions to just ignore them. That is: ftrace_exports_enabled, trace_event_exports_enabled, trace_marker_exports_enabled. -- Steve > > + event_trigger_unlock_commit_regs(fbuffer->trace_file, > > fbuffer->buffer, > > + fbuffer->event, fbuffer->entry, > > + fbuffer->flags, fbuffer->pc, > > fbuffer->regs); +} > > +EXPORT_SYMBOL_GPL(trace_event_buffer_commit); > > + > > void > > trace_function(struct trace_array *tr, > > unsigned long ip, unsigned long parent_ip, unsigned > > long flags, >
