1 -----------------------------------------------------------------------------
3 -- Module : System.CPUTime
4 -- Copyright : (c) The University of Glasgow 2001
5 -- License : BSD-style (see the file libraries/base/LICENSE)
7 -- Maintainer : libraries@haskell.org
8 -- Stability : provisional
9 -- Portability : portable
11 -- The standard CPUTime library.
13 -----------------------------------------------------------------------------
17 getCPUTime, -- :: IO Integer
18 cpuTimePrecision -- :: Integer
26 import Hugs.Time ( getCPUTime, clockTicks )
30 import CPUTime ( getCPUTime, cpuTimePrecision )
33 #ifdef __GLASGOW_HASKELL__
40 realToInteger :: Real a => a -> Integer
41 realToInteger ct = round (realToFrac ct :: Double)
42 -- CTime, CClock, CUShort etc are in Real but not Fractional,
43 -- so we must convert to Double before we can round it
45 #ifdef __GLASGOW_HASKELL__
46 -- -----------------------------------------------------------------------------
47 -- |Computation 'getCPUTime' returns the number of picoseconds CPU time
48 -- used by the current program. The precision of this result is
49 -- implementation-dependent.
51 getCPUTime :: IO Integer
54 #if !defined(mingw32_HOST_OS) && !defined(cygwin32_HOST_OS)
55 -- getrusage() is right royal pain to deal with when targetting multiple
56 -- versions of Solaris, since some versions supply it in libc (2.3 and 2.5),
57 -- while 2.4 has got it in libucb (I wouldn't be too surprised if it was back
58 -- again in libucb in 2.6..)
60 -- Avoid the problem by resorting to times() instead.
62 #if defined(HAVE_GETRUSAGE) && ! irix_HOST_OS && ! solaris2_HOST_OS
63 allocaBytes (#const sizeof(struct rusage)) $ \ p_rusage -> do
64 getrusage (#const RUSAGE_SELF) p_rusage
66 let ru_utime = (#ptr struct rusage, ru_utime) p_rusage
67 let ru_stime = (#ptr struct rusage, ru_stime) p_rusage
68 u_sec <- (#peek struct timeval,tv_sec) ru_utime :: IO CTime
69 u_usec <- (#peek struct timeval,tv_usec) ru_utime :: IO CTime
70 s_sec <- (#peek struct timeval,tv_sec) ru_stime :: IO CTime
71 s_usec <- (#peek struct timeval,tv_usec) ru_stime :: IO CTime
72 return ((realToInteger u_sec * 1000000 + realToInteger u_usec +
73 realToInteger s_sec * 1000000 + realToInteger s_usec)
77 foreign import ccall unsafe getrusage :: CInt -> Ptr CRUsage -> IO CInt
79 # if defined(HAVE_TIMES)
80 allocaBytes (#const sizeof(struct tms)) $ \ p_tms -> do
82 u_ticks <- (#peek struct tms,tms_utime) p_tms :: IO CClock
83 s_ticks <- (#peek struct tms,tms_stime) p_tms :: IO CClock
84 return (( (realToInteger u_ticks + realToInteger s_ticks) * 1000000000000)
85 `div` fromIntegral clockTicks)
88 foreign import ccall unsafe times :: Ptr CTms -> IO CClock
90 ioException (IOError Nothing UnsupportedOperation
98 -- NOTE: GetProcessTimes() is only supported on NT-based OSes.
99 -- The counts reported by GetProcessTimes() are in 100-ns (10^-7) units.
100 allocaBytes (#const sizeof(FILETIME)) $ \ p_creationTime -> do
101 allocaBytes (#const sizeof(FILETIME)) $ \ p_exitTime -> do
102 allocaBytes (#const sizeof(FILETIME)) $ \ p_kernelTime -> do
103 allocaBytes (#const sizeof(FILETIME)) $ \ p_userTime -> do
104 pid <- getCurrentProcess
105 ok <- getProcessTimes pid p_creationTime p_exitTime p_kernelTime p_userTime
107 ut <- ft2psecs p_userTime
108 kt <- ft2psecs p_kernelTime
112 ft2psecs :: Ptr FILETIME -> IO Integer
114 high <- (#peek FILETIME,dwHighDateTime) ft :: IO Word32
115 low <- (#peek FILETIME,dwLowDateTime) ft :: IO Word32
116 -- Convert 100-ns units to picosecs (10^-12)
117 -- => multiply by 10^5.
118 return (((fromIntegral high) * (2^32) + (fromIntegral low)) * 100000)
120 -- ToDo: pin down elapsed times to just the OS thread(s) that
121 -- are evaluating/managing Haskell code.
125 -- need proper Haskell names (initial lower-case character)
126 foreign import stdcall unsafe "GetCurrentProcess" getCurrentProcess :: IO (Ptr HANDLE)
127 foreign import stdcall unsafe "GetProcessTimes" getProcessTimes :: Ptr HANDLE -> Ptr FILETIME -> Ptr FILETIME -> Ptr FILETIME -> Ptr FILETIME -> IO CInt
129 #endif /* not _WIN32 */
130 #endif /* __GLASGOW_HASKELL__ */
132 -- |The 'cpuTimePrecision' constant is the smallest measurable difference
133 -- in CPU time that the implementation can record, and is given as an
134 -- integral number of picoseconds.
137 cpuTimePrecision :: Integer
138 cpuTimePrecision = round ((1000000000000::Integer) % fromIntegral (clockTicks))
141 #ifdef __GLASGOW_HASKELL__
147 unsafePerformIO (sysconf (#const _SC_CLK_TCK) >>= return . fromIntegral)
148 foreign import ccall unsafe sysconf :: CInt -> IO CLong
150 #endif /* __GLASGOW_HASKELL__ */