diff options
Diffstat (limited to 'gcc/ada/5atpopsp.adb')
| -rw-r--r-- | gcc/ada/5atpopsp.adb | 194 |
1 files changed, 21 insertions, 173 deletions
diff --git a/gcc/ada/5atpopsp.adb b/gcc/ada/5atpopsp.adb index 937041e22c1..dc4c0135f50 100644 --- a/gcc/ada/5atpopsp.adb +++ b/gcc/ada/5atpopsp.adb @@ -2,12 +2,11 @@ -- -- -- GNU ADA 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 . O P E R A T I O N S . -- --- S P E C I F I C -- +-- SYSTEM.TASK_PRIMITIVES.OPERATIONS.SPECIFIC -- -- -- -- B o d y -- -- -- --- Copyright (C) 1992-2001, Free Software Foundation, Inc. -- +-- Copyright (C) 1992-2003, Free Software Foundation, Inc. -- -- -- -- 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- -- @@ -34,194 +33,42 @@ -- This is a POSIX version of this package where foreign threads are -- recognized. --- Currently, DEC Unix, SCO UnixWare, Solaris pthread, HPUX pthread, --- GNU/Linux threads and RTEMS use this version. - -with System.Task_Info; --- Use for Unspecified_Task_Info -with System.Soft_Links; --- used to initialize TSD for a C thread, in function Self +-- Currently, DEC Unix, SCO UnixWare, Solaris pthread, HPUX pthread, +-- GNU/Linux threads, and RTEMS use this version. separate (System.Task_Primitives.Operations) package body Specific is - ------------------ - -- Local Data -- - ------------------ - - -- The followings are logically constants, but need to be initialized - -- at run time. - - ATCB_Key : aliased pthread_key_t; - -- Key used to find the Ada Task_ID associated with a thread - - -- The following are used to allow the Self function to - -- automatically generate ATCB's for C threads that happen to call - -- Ada procedure, which in turn happen to call the Ada runtime system. - - type Fake_ATCB; - type Fake_ATCB_Ptr is access Fake_ATCB; - type Fake_ATCB is record - Stack_Base : Interfaces.C.unsigned := 0; - -- A value of zero indicates the node is not in use. - Next : Fake_ATCB_Ptr; - Real_ATCB : aliased Ada_Task_Control_Block (0); - end record; - - Fake_ATCB_List : Fake_ATCB_Ptr; - -- A linear linked list. - -- The list is protected by Single_RTS_Lock; - -- Nodes are added to this list from the front. - -- Once a node is added to this list, it is never removed. - - Fake_Task_Elaborated : aliased Boolean := True; - -- Used to identified fake tasks (i.e., non-Ada Threads). - - Next_Fake_ATCB : Fake_ATCB_Ptr; - -- Used to allocate one Fake_ATCB in advance. See comment in New_Fake_ATCB - - ----------------------- - -- Local Subprograms -- - ----------------------- - - --------------------------------- - -- Support for New_Fake_ATCB -- - --------------------------------- - - function New_Fake_ATCB return Task_ID; - -- Allocate and Initialize a new ATCB. This code can safely be called from - -- a foreign thread, as it doesn't access implicitly or explicitly - -- "self" before having initialized the new ATCB. - - ------------------- - -- New_Fake_ATCB -- - ------------------- - - function New_Fake_ATCB return Task_ID is - Self_ID : Task_ID; - P, Q : Fake_ATCB_Ptr; - Succeeded : Boolean; - Result : Interfaces.C.int; - - begin - -- This section is ticklish. - -- We dare not call anything that might require an ATCB, until - -- we have the new ATCB in place. - - Lock_RTS; - Q := null; - P := Fake_ATCB_List; - - while P /= null loop - if P.Stack_Base = 0 then - Q := P; - end if; - - P := P.Next; - end loop; - - if Q = null then - - -- Create a new ATCB with zero entries. - - Self_ID := Next_Fake_ATCB.Real_ATCB'Access; - Next_Fake_ATCB.Stack_Base := 1; - Next_Fake_ATCB.Next := Fake_ATCB_List; - Fake_ATCB_List := Next_Fake_ATCB; - Next_Fake_ATCB := null; - - else - -- Reuse an existing fake ATCB. - - Self_ID := Q.Real_ATCB'Access; - Q.Stack_Base := 1; - end if; - - -- Record this as the Task_ID for the current thread. - - Self_ID.Common.LL.Thread := pthread_self; - Result := pthread_setspecific (ATCB_Key, To_Address (Self_ID)); - pragma Assert (Result = 0); - - -- Do the standard initializations - - System.Tasking.Initialize_ATCB - (Self_ID, null, Null_Address, Null_Task, Fake_Task_Elaborated'Access, - System.Priority'First, Task_Info.Unspecified_Task_Info, 0, Self_ID, - Succeeded); - pragma Assert (Succeeded); - - -- Finally, it is safe to use an allocator in this thread. - - if Next_Fake_ATCB = null then - Next_Fake_ATCB := new Fake_ATCB; - end if; - - Self_ID.Master_of_Task := 0; - Self_ID.Master_Within := Self_ID.Master_of_Task + 1; - - for L in Self_ID.Entry_Calls'Range loop - Self_ID.Entry_Calls (L).Self := Self_ID; - Self_ID.Entry_Calls (L).Level := L; - end loop; - - Self_ID.Common.State := Runnable; - Self_ID.Awake_Count := 1; - - -- Since this is not an ordinary Ada task, we will start out undeferred - - Self_ID.Deferral_Level := 0; - - System.Soft_Links.Create_TSD (Self_ID.Common.Compiler_Data); - - -- ???? - -- The following call is commented out to avoid dependence on - -- the System.Tasking.Initialization package. - -- It seems that if we want Ada.Task_Attributes to work correctly - -- for C threads we will need to raise the visibility of this soft - -- link to System.Soft_Links. - -- We are putting that off until this new functionality is otherwise - -- stable. - -- System.Tasking.Initialization.Initialize_Attributes_Link.all (T); - - for J in Known_Tasks'Range loop - if Known_Tasks (J) = null then - Known_Tasks (J) := Self_ID; - Self_ID.Known_Tasks_Index := J; - exit; - end if; - end loop; - - -- Must not unlock until Next_ATCB is again allocated. - - Unlock_RTS; - return Self_ID; - end New_Fake_ATCB; - ---------------- -- Initialize -- ---------------- procedure Initialize (Environment_Task : Task_ID) is + pragma Warnings (Off, Environment_Task); Result : Interfaces.C.int; + begin Result := pthread_key_create (ATCB_Key'Access, null); pragma Assert (Result = 0); - Result := pthread_setspecific (ATCB_Key, To_Address (Environment_Task)); - pragma Assert (Result = 0); + end Initialize; - -- Create a free ATCB for use on the Fake_ATCB_List. + ------------------- + -- Is_Valid_Task -- + ------------------- - Next_Fake_ATCB := new Fake_ATCB; - end Initialize; + function Is_Valid_Task return Boolean is + begin + return pthread_getspecific (ATCB_Key) /= System.Null_Address; + end Is_Valid_Task; --------- -- Set -- --------- procedure Set (Self_Id : Task_ID) is - Result : Interfaces.C.int; + Result : Interfaces.C.int; + begin Result := pthread_setspecific (ATCB_Key, To_Address (Self_Id)); pragma Assert (Result = 0); @@ -246,16 +93,17 @@ package body Specific is function Self return Task_ID is Result : System.Address; + begin Result := pthread_getspecific (ATCB_Key); -- If the key value is Null, then it is a non-Ada task. - if Result = System.Null_Address then - return New_Fake_ATCB; + if Result /= System.Null_Address then + return To_Task_Id (Result); + else + return Register_Foreign_Thread; end if; - - return To_Task_ID (Result); end Self; end Specific; |