diff options
Diffstat (limited to 'gcc/ada/s-taspri-posix.ads')
| -rw-r--r-- | gcc/ada/s-taspri-posix.ads | 59 |
1 files changed, 40 insertions, 19 deletions
diff --git a/gcc/ada/s-taspri-posix.ads b/gcc/ada/s-taspri-posix.ads index 1717cce47f5..3e31f7e46cf 100644 --- a/gcc/ada/s-taspri-posix.ads +++ b/gcc/ada/s-taspri-posix.ads @@ -1,13 +1,13 @@ ------------------------------------------------------------------------------ -- -- --- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS -- +-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS -- -- -- -- S Y S T E M . T A S K _ P R I M I T I V E S -- -- -- -- S p e c -- -- -- -- Copyright (C) 1991-1994, Florida State University -- --- Copyright (C) 1995-2003, Ada Core Technologies -- +-- Copyright (C) 1995-2005, AdaCore -- -- -- -- GNARL is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- @@ -32,8 +32,9 @@ -- -- ------------------------------------------------------------------------------ --- This is a POSIX-like version of this package. --- Note: this file can only be used for POSIX compliant systems. +-- This is a POSIX-like version of this package + +-- Note: this file can only be used for POSIX compliant systems pragma Polling (Off); -- Turn off polling, we do not want ATC polling to take place during @@ -47,36 +48,55 @@ with System.OS_Interface; package System.Task_Primitives is type Lock is limited private; - -- Should be used for implementation of protected objects. + -- Should be used for implementation of protected objects type RTS_Lock is limited private; - -- Should be used inside the runtime system. - -- The difference between Lock and the RTS_Lock is that the later - -- one serves only as a semaphore so that do not check for - -- ceiling violations. + -- Should be used inside the runtime system. The difference between Lock + -- and the RTS_Lock is that the later one serves only as a semaphore so + -- that do not check for ceiling violations. + + type Suspension_Object is limited private; + -- Should be used for the implementation of Ada.Synchronous_Task_Control type Task_Body_Access is access procedure; - -- Pointer to the task body's entry point (or possibly a wrapper - -- declared local to the GNARL). + -- Pointer to the task body's entry point (or possibly a wrapper declared + -- local to the GNARL). type Private_Data is limited private; - -- Any information that the GNULLI needs maintained on a per-task - -- basis. A component of this type is guaranteed to be included - -- in the Ada_Task_Control_Block. + -- Any information that the GNULLI needs maintained on a per-task basis. + -- A component of this type is guaranteed to be included in the + -- Ada_Task_Control_Block. private type Lock is new System.OS_Interface.pthread_mutex_t; type RTS_Lock is new System.OS_Interface.pthread_mutex_t; + type Suspension_Object is record + State : Boolean; + pragma Atomic (State); + -- Boolean that indicates whether the object is open. This field is + -- marked Atomic to ensure that we can read its value without locking + -- the access to the Suspension_Object. + + Waiting : Boolean; + -- Flag showing if there is a task already suspended on this object + + L : aliased System.OS_Interface.pthread_mutex_t; + -- Protection for ensuring mutual exclusion on the Suspension_Object + + CV : aliased System.OS_Interface.pthread_cond_t; + -- Condition variable used to queue threads until condition is signaled + end record; + type Private_Data is record Thread : aliased System.OS_Interface.pthread_t; pragma Atomic (Thread); -- Thread field may be updated by two different threads of control. - -- (See, Enter_Task and Create_Task in s-taprop.adb). - -- They put the same value (thr_self value). We do not want to - -- use lock on those operations and the only thing we have to - -- make sure is that they are updated in atomic fashion. + -- (See, Enter_Task and Create_Task in s-taprop.adb). They put the same + -- value (thr_self value). We do not want to use lock on those + -- operations and the only thing we have to make sure is that they are + -- updated in atomic fashion. LWP : aliased System.Address; -- The purpose of this field is to provide a better tasking support on @@ -84,8 +104,9 @@ private -- On targets where lwp is not relevant, this is equivalent to Thread. CV : aliased System.OS_Interface.pthread_cond_t; + -- Should be commented ??? (in all versions of taspri) - L : aliased RTS_Lock; + L : aliased RTS_Lock; -- Protection for all components is lock L end record; |