tracing: Fix double CPP substitution in TRACE_EVENT_FN

TRACE_EVENT_FN relays on TRACE_EVENT by reprocessing its parameters
into the ftrace events CPP macro. This leads to a double substitution
in some cases.

For example, a bad consequence is a format always prefixed by
"%s, %s\n" for every TRACE_EVENT_FN based events.

Eg:
	cat /debug/tracing/events/syscalls/sys_enter/format
	[...]
	print fmt: "%s, %s\n", "\"NR %ld (%lx, %lx, %lx, %lx, %lx, %lx)\"",\
	"REC->id, REC->args[0], REC->args[1], REC->args[2], REC->args[3],\
	REC->args[4], REC->args[5]"

This creates a failure in post-processing tools such as perf trace or
trace-cmd.

Then drop this double substitution and replace it by a new __cpparg()
macro that relays CPP arguments containing commas.

Signed-off-by: Frederic Weisbecker <[email protected]>
Cc: Josh Stone <[email protected]>
Cc: Li Zefan <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Jason Baron <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions