tasks refactor

zeroflag · Dec 17, 2017 · 1129430 · 1129430
1 parent 9e3ca57
commit 1129430
Showing 1 changed file with 40 additions and 54 deletions.
diff --git a/arch/esp8266/forth/tasks.forth b/arch/esp8266/forth/tasks.forth
@@ -18,104 +18,90 @@ SKIPPED INTERPRETER .status !
 _s0 INTERPRETER .s0 !
 _r0 INTERPRETER .r0 !
 
-112 init-variable: var-task-stack-size
-112 init-variable: var-task-rstack-size
-INTERPRETER init-variable: var-last-task
-INTERPRETER init-variable: var-current-task
+112 init-variable: task-stack-size
+112 init-variable: task-rstack-size
+INTERPRETER init-variable: last
+INTERPRETER init-variable: current
 
-: last-task ( -- task ) var-last-task @ ;
-: last-task! ( task -- ) var-last-task ! ;
-: current-task ( -- task ) var-current-task @ ;
-: current-task! ( task -- ) var-current-task ! ;
-
-: alloc-data-stack ( -- a ) var-task-stack-size @ allot here ;
-: alloc-return-stack ( -- a ) var-task-rstack-size @ allot here ;
+: alloc-stack  ( -- a ) task-stack-size  @ allot here ;
+: alloc-rstack ( -- a ) task-rstack-size @ allot here ;
 
 : task: ( user-space-size "name" ) ( -- task )
     create:
         here                                 \ task header begins here
         swap Task + allot                    \ make room for task header + user space
         SKIPPED             over .status !   \ new status is SKIPPED
-        last-task .next @   over .next !     \ this.next = last-task.next
-        dup last-task .next !                \ last-task.next = this
-        alloc-data-stack    over .sp !       \ this.sp = allocated
-        alloc-return-stack  over .rp !       \ this.sp = allocated
+        last @ .next @      over .next !     \ this.next = last-task.next
+        dup last @               .next !     \ last-task.next = this
+        alloc-stack         over .sp !       \ this.sp = allocated
+        alloc-rstack        over .rp !       \ this.sp = allocated
         0                   over .handler !  \ exception handler of this thread
         dup .sp @ over .s0 !                 \ init s0 = top of stack address
         dup .rp @ over .r0 !                 \ init r0 = top of rstack address
-        last-task! ;                         \ last-task = this
-
-: task-choose-next ( -- ) current-task begin .next @ dup .status @ PAUSED = until ;
+        last ! ;                             \ last-task = this
 
-: task-save-context ( sp ip rp -- ) \ XXX temporal coupling
-    current-task .rp !
-    current-task .ip !
-    current-task .sp ! ;
+: choose ( -- ) current @ begin .next @ dup .status @ PAUSED = until ;
 
-: task-restore-context ( -- )    
-    current-task .sp @ sp!
-    current-task .rp @ rp!
-    current-task .ip @ >r ;
+: save ( sp ip rp -- ) \ XXX temporal coupling
+    current @ .rp !
+    current @ .ip !
+    current @ .sp ! ;
 
-: task-run ( task -- )
-    current-task!
-    SKIPPED current-task .status !
-    task-restore-context ;
+: restore ( -- )    
+    current @ .sp @ sp!
+    current @ .rp @ rp!
+    current @ .ip @ >r ;
 
-: task-user-space ( task -- a ) Task + ;
+: switch ( task -- )
+    current !
+    SKIPPED current @ .status !
+    restore ;
 
-: user-space ( -- a ) current-task task-user-space ;
+: user-space ( -- a ) current @ Task + ;
 
 defer: pause
 
 : pause-multi ( -- )
-    PAUSED current-task .status !
-    sp@ r> rp@ task-save-context
-    task-choose-next task-run ;
-
-: pause-single ( -- ) ;
+    PAUSED current @ .status !
+    sp@ r> rp@ save
+    choose switch ;
 
-: s0-multi ( -- top-stack-adr ) current-task .s0 @ ;
-: r0-multi ( -- top-rstack-adr ) current-task .r0 @ ;
+: s0-multi ( -- top-stack-adr )  current @ .s0 @ ;
+: r0-multi ( -- top-rstack-adr ) current @ .r0 @ ;
 
 ' s0 is: s0-multi
 ' r0 is: r0-multi
 
 : activate ( task -- )
     r> over .ip !
-    PAUSED current-task .status !   \ pause current task
-    sp@ cell + r> rp@ task-save-context        
-    task-run ;
+    PAUSED current @ .status !   \ pause current task
+    sp@ cell + r> rp@ save
+    switch ;
 
-: stop ( task -- )
-    SKIPPED swap .status ! 
-    task-choose-next task-run ;
-
-: deactivate ( -- ) current-task stop ;
+: stop ( task -- ) SKIPPED swap .status ! choose switch ;
+: deactivate ( -- ) current @ stop ;
 
 : task-find ( task -- link )
     lastword
     begin
         dup
     while
         2dup
-        link>body cell + = if \ XXX skip behaviour pointer
-            nip exit
-        then
+        link>body cell + = if nip exit then \ XXX skip behaviour pointer
         @
     repeat
     2drop 0 ;
 
 : tasks-print ( -- )
-    current-task
+    current @
     begin
         dup task-find ?dup if
             link-type cr
         else
             println: "interpreter"
         then
         .next @ dup
-        current-task =
+        current @ =
     until
     drop ;
 
@@ -125,7 +111,7 @@ defer: pause
 : wait ( semaphore -- ) begin pause dup @ until -1 swap +! ; 
 : signal ( semaphore -- ) 1 swap +!  pause ;
 
-: multi-handler ( -- a ) current-task .handler ;
+: multi-handler ( -- a ) current @ .handler ;
 
 : multi ( -- ) \ switch to multi-task mode
     ['] handler is: multi-handler \ each tasks should have its own exception handler
@@ -135,6 +121,6 @@ defer: pause
 : single ( -- ) \ switch to signle-task mode
     ['] handler is: single-handler \ use global handler
     0 xpause !
-    ['] pause is: pause-single ;
+    ['] pause is: nop ;
 
 single