Use this to replace kdebug.h so you can inject events into instruments: https://developer.apple.com/library/ios/documentation/AnalysisTools/Conceptual/WhatsNewInstruments/NewFeatures41/NewFeatures41.html

kdebug-minimal.h

#ifndef DBG_MACH_CHUD

#define DBG_MACH_CHUD 0x0A
#define DBG_FUNC_START 1
#define DBG_FUNC_END 2
#define DBG_APPS              33

#define KDBG_CODE(Class, SubClass, code) (((Class & 0xff) << 24) | ((SubClass & 0xff) << 16) | ((code & 0x3fff)  << 2))
#define APPSDBG_CODE(SubClass,code) KDBG_CODE(DBG_APPS, SubClass, code)

#endif

FYI, I hunted around for a definition for SYS_kdebug_trace and finally found the following.

#define SYS_kdebug_trace 180