perf scripts: Fallback to syscalls:* when raw_syscalls:* is not available

Older kernels (e.g., RHEL6) do system call tracing via the
syscalls:sys_{enter,exit} tracepoints rather than using raw_syscalls:*.

Update perf python and perl scripts to fallback to syscalls:* when
raw_syscalls:* isn't available.

Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/5a6c64081a3375bc3bc66351b14559678ef4d71e.1402507908.git.bristot@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/scripts/python/syscall-counts-by-pid.py b/tools/perf/scripts/python/syscall-counts-by-pid.py
index c64d1c5..cf2054c 100644
--- a/tools/perf/scripts/python/syscall-counts-by-pid.py
+++ b/tools/perf/scripts/python/syscall-counts-by-pid.py
@@ -48,6 +48,11 @@
 	except TypeError:
 		syscalls[common_comm][common_pid][id] = 1
 
+def syscalls__sys_enter(event_name, context, common_cpu,
+	common_secs, common_nsecs, common_pid, common_comm,
+	id, args):
+	raw_syscalls__sys_enter(**locals())
+
 def print_syscall_totals():
     if for_comm is not None:
 	    print "\nsyscall events for %s:\n\n" % (for_comm),