diff options
Diffstat (limited to 'rts/Task.h')
| -rw-r--r-- | rts/Task.h | 35 |
1 files changed, 10 insertions, 25 deletions
diff --git a/rts/Task.h b/rts/Task.h index 590dd679b3..c11afb584c 100644 --- a/rts/Task.h +++ b/rts/Task.h @@ -20,26 +20,14 @@ Task, and OS threads that enter the Haskell RTS for the purposes of making a call-in are also Tasks. - The relationship between the number of tasks and capabilities, and - the runtime build (-threaded, -smp etc.) is summarised by the - following table: + In the THREADED_RTS build, multiple Tasks may all be running + Haskell code simultaneously. A task relinquishes its Capability + when it is asked to evaluate an external (C) call. - build Tasks Capabilities - --------------------------------- - normal 1 1 - -threaded N N - - The non-threaded build has a single Task and a single global - Capability. - - The THREADED_RTS build allows multiple tasks and mulitple Capabilities. - Multiple Tasks may all be running Haskell code simultaneously. A task - relinquishes its Capability when it is asked to evaluate an external - (C) call. - - In general, there may be multiple Tasks for an OS thread. This - happens if one Task makes a foreign call from Haskell, and - subsequently calls back in to create a new bound thread. + In general, there may be multiple Tasks associated with a given OS + thread. A second Task is created when one Task makes a foreign + call from Haskell, and subsequently calls back in to Haskell, + creating a new bound thread. A particular Task structure can belong to more than one OS thread over its lifetime. This is to avoid creating an unbounded number @@ -190,7 +178,10 @@ INLINE_HEADER void taskEnter (Task *task); // mainly for stats-gathering purposes. // Requires: sched_mutex. // +#if defined(THREADED_RTS) +// In the non-threaded RTS, tasks never stop. void workerTaskStop (Task *task); +#endif // Record the time spent in this Task. // This is called by workerTaskStop() but not by boundTaskExiting(), @@ -207,12 +198,6 @@ void discardTask (Task *task); // INLINE_HEADER Task *myTask (void); -// After a fork, the tasks are not carried into the child process, so -// we must tell the task manager. -// Requires: sched_mutex. -// -void resetTaskManagerAfterFork (void); - #if defined(THREADED_RTS) // Workers are attached to the supplied Capability. This Capability |