perf tools: Introduce veprintf

va_args alternative to eprintf().

Signed-off-by: Wang Nan <[e-mail]>
Acked-by: Alexei Starovoitov <[e-mail]>
Cc: Brendan Gregg <[e-mail]>
Cc: Daniel Borkmann <[e-mail]>
Cc: David Ahern <[e-mail]>
Cc: He Kuang <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Kaixu Xia <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Zefan Li <[e-mail]>
Cc: [e-mail]
Link: http://lkml.kernel.org/n/[e-mail]
[ split from another patch ]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/debug.c

···
 	return ret;
 }
 
+int veprintf(int level, int var, const char *fmt, va_list args)
+{
+	return _eprintf(level, var, fmt, args);
+}
+
 int eprintf(int level, int var, const char *fmt, ...)
 {
 	va_list args;

tools/perf/util/debug.h

···
 
 int eprintf(int level, int var, const char *fmt, ...) __attribute__((format(printf, 3, 4)));
 int eprintf_time(int level, int var, u64 t, const char *fmt, ...) __attribute__((format(printf, 4, 5)));
+int veprintf(int level, int var, const char *fmt, va_list args);
 
 int perf_debug_option(const char *str);