X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=GHC%2FConc.lhs;h=0d174578a65b55bb9f64c02ee77a0ad5da47b9e5;hb=0bf2fdab482da7a287ef09f18e7656abe62256d0;hp=ec6e0642d1fab84c8c393e99c4321a0ceaa49a7d;hpb=cdd378d922a7bc4995c21643bf5d4d19581692ab;p=ghc-base.git diff --git a/GHC/Conc.lhs b/GHC/Conc.lhs index ec6e064..0d17457 100644 --- a/GHC/Conc.lhs +++ b/GHC/Conc.lhs @@ -29,8 +29,11 @@ module GHC.Conc -- * Forking and suchlike , forkIO -- :: IO a -> IO ThreadId + , forkIOUnmasked , forkOnIO -- :: Int -> IO a -> IO ThreadId + , forkOnIOUnmasked , numCapabilities -- :: Int + , numSparks -- :: IO Int , childHandler -- :: Exception -> IO () , myThreadId -- :: IO ThreadId , killThread -- :: ThreadId -> IO () @@ -211,8 +214,8 @@ thread. The new thread will be a lightweight thread; if you want to use a foreign library that uses thread-local storage, use 'Control.Concurrent.forkOS' instead. -GHC note: the new thread inherits the /blocked/ state of the parent -(see 'Control.Exception.block'). +GHC note: the new thread inherits the /masked/ state of the parent +(see 'Control.Exception.mask'). The newly created thread has an exception handler that discards the exceptions 'BlockedIndefinitelyOnMVar', 'BlockedIndefinitelyOnSTM', and @@ -225,6 +228,11 @@ forkIO action = IO $ \ s -> where action_plus = catchException action childHandler +-- | Like 'forkIO', but the child thread is created with asynchronous exceptions +-- unmasked (see 'Control.Exception.mask'). +forkIOUnmasked :: IO () -> IO ThreadId +forkIOUnmasked io = forkIO (unsafeUnmask io) + {- | Like 'forkIO', but lets you specify on which CPU the thread is created. Unlike a `forkIO` thread, a thread created by `forkOnIO` @@ -244,6 +252,11 @@ forkOnIO (I# cpu) action = IO $ \ s -> where action_plus = catchException action childHandler +-- | Like 'forkOnIO', but the child thread is created with +-- asynchronous exceptions unmasked (see 'Control.Exception.mask'). +forkOnIOUnmasked :: Int -> IO () -> IO ThreadId +forkOnIOUnmasked cpu io = forkOnIO cpu (unsafeUnmask io) + -- | the value passed to the @+RTS -N@ flag. This is the number of -- Haskell threads that can run truly simultaneously at any given -- time, and is typically set to the number of physical CPU cores on @@ -253,6 +266,10 @@ numCapabilities = unsafePerformIO $ do n <- peek n_capabilities return (fromIntegral n) +-- | Returns the number of sparks currently in the local spark pool +numSparks :: IO Int +numSparks = IO $ \s -> case numSparks# s of (# s', n #) -> (# s', I# n #) + #if defined(mingw32_HOST_OS) && defined(__PIC__) foreign import ccall "_imp__n_capabilities" n_capabilities :: Ptr CInt #else @@ -301,7 +318,7 @@ another thread. If the target thread is currently making a foreign call, then the exception will not be raised (and hence 'throwTo' will not return) until the call has completed. This is the case regardless of whether -the call is inside a 'block' or not. +the call is inside a 'mask' or not. Important note: the behaviour of 'throwTo' differs from that described in the paper \"Asynchronous exceptions in Haskell\" @@ -611,18 +628,18 @@ MVar utilities \begin{code} withMVar :: MVar a -> (a -> IO b) -> IO b withMVar m io = - block $ do + mask $ \restore -> do a <- takeMVar m - b <- catchAny (unblock (io a)) + b <- catchAny (restore (io a)) (\e -> do putMVar m a; throw e) putMVar m a return b modifyMVar_ :: MVar a -> (a -> IO a) -> IO () modifyMVar_ m io = - block $ do + mask $ \restore -> do a <- takeMVar m - a' <- catchAny (unblock (io a)) + a' <- catchAny (restore (io a)) (\e -> do putMVar m a; throw e) putMVar m a' return () @@ -861,7 +878,7 @@ prodServiceThread = do -- sharedCAF :: a -> (Ptr a -> IO (Ptr a)) -> IO a sharedCAF a get_or_set = - block $ do + mask_ $ do stable_ref <- newStablePtr a let ref = castPtr (castStablePtrToPtr stable_ref) ref2 <- get_or_set ref