CLOCK_THREAD_CPUTIME_ID On MacOSX

Question

I have a function that I port from Linux to MacOSX that uses clock_gettime with CLOCK_THREAD_CPUTIME_ID to measure the time spent on the process. I found this code on the Internet that would give me the equivalent of CLOCK_REALTIME:

#ifdef __MACH__ // OS X does not have clock_gettime, use clock_get_time clock_serv_t cclock; mach_timespec_t ts; host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock); clock_get_time(cclock, &ts); mach_port_deallocate(mach_task_self(), cclock); #else timespec ts; clock_gettime(CLOCK_REALTIME, ts); #endif 

But I cannot find an easy way to get clock_gettime (CLOCK_THREAD_CPUTIME_ID, ts); Does anyone know a good solution for this?

Answer 1

I recently ported part of the pcsx2 project to Darwin / OSX, and I needed something similar to CLOCK_THREAD_CPUTIME_ID . Here is what I came up with:

 #include <stdint.h> #include <mach/mach_init.h> #include <mach/thread_act.h> #include <mach/mach_port.h> typedef uint64_t u64; // gets the CPU time used by the current thread (both system and user), in // microseconds, returns 0 on failure static u64 getthreadtime(thread_port_t thread) { mach_msg_type_number_t count = THREAD_BASIC_INFO_COUNT; thread_basic_info_data_t info; int kr = thread_info(thread, THREAD_BASIC_INFO, (thread_info_t) &info, &count); if (kr != KERN_SUCCESS) { return 0; } // add system and user time return (u64) info.user_time.seconds * (u64) 1e6 + (u64) info.user_time.microseconds + (u64) info.system_time.seconds * (u64) 1e6 + (u64) info.system_time.microseconds; } // Returns the CPU time the calling thread has used (system + user) in // units of 100 nanoseconds. The weird units are to mirror the Windows // counterpart in WinThreads.cpp, which uses the GetThreadTimes() API. On // OSX/Darwin, this is only accurate up until 1ms (and possibly less), so // not very good. u64 Threading::GetThreadCpuTime() { thread_port_t thread = mach_thread_self(); u64 us = getthreadtime(thread); mach_port_deallocate(mach_task_self(), thread); return us * 10ULL; }