X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Ftarget-unithread.lisp;h=1d5a4949c435c98f990a2506f27f68860d3652b6;hb=bb756e3d4b19c30d4a9cd4250b606c5969613ad9;hp=bd57e74e537b07ad19cfdd7f5901188dcac454ae;hpb=d767105094f5836327f9389b061f83a44240a279;p=sbcl.git

diff --git a/src/code/target-unithread.lisp b/src/code/target-unithread.lisp
index bd57e74..1d5a494 100644
--- a/src/code/target-unithread.lisp
+++ b/src/code/target-unithread.lisp
@@ -1,123 +1,72 @@
+;;;; unithread stub support for threads in the target machine
+
+;;;; This software is part of the SBCL system. See the README file for
+;;;; more information.
+;;;;
+;;;; This software is derived from the CMU CL system, which was
+;;;; written at Carnegie Mellon University and released into the
+;;;; public domain. The software is in the public domain and is
+;;;; provided with absolutely no warranty. See the COPYING and CREDITS
+;;;; files for more information.
+
 (in-package "SB!THREAD")
 
+;;; used bu debug-int.lisp to access interrupt contexts
 #!-sb-fluid (declaim (inline sb!vm::current-thread-offset-sap))
-(defun sb!vm::current-thread-offset-sap (n) 
+(defun sb!vm::current-thread-offset-sap (n)
   (declare (type (unsigned-byte 27) n))
-  (sb!sys:sap-ref-sap (alien-sap (extern-alien "all_threads" (* t))) 
-	       (* n 4)))
+  (sb!sys:sap-ref-sap (alien-sap (extern-alien "all_threads" (* t)))
+               (* n sb!vm:n-word-bytes)))
 
-(defun current-thread-id ()
-  (sb!sys:sap-int
-   (sb!vm::current-thread-offset-sap sb!vm::thread-pid-slot)))
-
-;;;; queues, locks 
+;;;; queues, locks
 
 ;; spinlocks use 0 as "free" value: higher-level locks use NIL
-(defun get-spinlock (lock offset new-value) )
+(defun get-spinlock (lock offset new-value)
+  (declare (ignore lock offset new-value)))
 
 (defmacro with-spinlock ((queue) &body body)
+  (declare (ignore queue))
   `(progn ,@body))
 
 ;;;; the higher-level locking operations are based on waitqueues
 
 (defstruct waitqueue
-  (name nil :type (or null simple-base-string))
+  (name nil :type (or null simple-string))
   (lock 0)
   (data nil))
 
 (defstruct (mutex (:include waitqueue))
   (value nil))
 
-#+nil
-(defun wait-on-queue (queue &optional lock)
-  (let ((pid (current-thread-id)))
-    ;; FIXME what should happen if we get interrupted when we've blocked
-    ;; the sigcont?  For that matter, can we get interrupted?
-    (block-sigcont)
-    (when lock (release-mutex lock))
-    (get-spinlock queue 2 pid)
-    (pushnew pid (waitqueue-data queue))
-    (setf (waitqueue-lock queue) 0)
-    (unblock-sigcont-and-sleep)))
-
-#+nil
-(defun dequeue (queue)
-  (let ((pid (current-thread-id)))
-    (get-spinlock queue 2 pid)
-    (setf (waitqueue-data queue)
-	  (delete pid (waitqueue-data queue)))
-    (setf (waitqueue-lock queue) 0)))
-
-#+nil
-(defun signal-queue-head (queue)
-  (let ((pid (current-thread-id)))
-    (get-spinlock queue 2 pid)
-    (let ((h (car (waitqueue-data queue))))
-      (setf (waitqueue-lock queue) 0)
-      (when h
-	(sb!unix:unix-kill h :sigcont)))))
-
 ;;;; mutex
 
-#+nil
 (defun get-mutex (lock &optional new-value (wait-p t))
   (declare (type mutex lock))
-  (let ((pid (current-thread-id)))
-    (unless new-value (setf new-value pid))
-    (assert (not (eql new-value (mutex-value lock))))
-    (loop
-     (unless
-	 ;; args are object slot-num old-value new-value
-	 (sb!vm::%instance-set-conditional lock 4 nil new-value)
-       (dequeue lock)
-       (return t))
-     (unless wait-p (return nil))
-     (wait-on-queue lock nil))))
-
-#+nil
-(defun release-mutex (lock &optional (new-value nil))
+  (let ((old-value (mutex-value lock)))
+    (when (and old-value wait-p)
+      (error "In unithread mode, mutex ~S was requested with WAIT-P ~S and ~
+              new-value ~S, but has already been acquired (with value ~S)."
+             lock wait-p new-value old-value))
+    (setf (mutex-value lock) new-value)
+    t))
+
+(defun release-mutex (lock)
   (declare (type mutex lock))
-  (let ((old-value (mutex-value lock))
-	(t1 nil))
-    (loop
-     (unless
-	 ;; args are object slot-num old-value new-value
-	 (eql old-value
-	      (setf t1
-		    (sb!vm::%instance-set-conditional lock 4 old-value new-value)))       
-       (signal-queue-head lock)
-       (return t))
-     (setf old-value t1))))
-
-(defmacro with-mutex ((mutex &key value (wait-p t))  &body body)
-  (declare (ignore mutex value wait-p))
-  `(progn ,@body))
-
-;;; what's the best thing to do with these on unithread?
-#+NIl
-(defun condition-wait (queue lock)
-  "Atomically release LOCK and enqueue ourselves on QUEUE.  Another
-thread may subsequently notify us using CONDITION-NOTIFY, at which
-time we reacquire LOCK and return to the caller."
-  (unwind-protect
-       (wait-on-queue queue lock)
-    ;; If we are interrupted while waiting, we should do these things
-    ;; before returning.  Ideally, in the case of an unhandled signal,
-    ;; we should do them before entering the debugger, but this is
-    ;; better than nothing.
-    (dequeue queue)
-    (get-mutex lock)))
-
-#+nil
-(defun condition-notify (queue)
-  "Notify one of the processes waiting on QUEUE"
-  (signal-queue-head queue))
-
+  (setf (mutex-value lock) nil))
 
-;;;; multiple independent listeners
 
-(defvar *session-lock* nil)
+;; FIXME need suitable stub or ERROR-signaling definitions for
+;; condition-wait (queue lock)
+;; condition-notify (queue)
 
 ;;;; job control
 
-(defun debugger-wait-until-foreground-thread (stream) t)
+(defun init-job-control () t)
+(defun debugger-wait-until-foreground-thread (stream)
+  (declare (ignore stream))
+  t)
+(defun get-foreground () t)
+(defun release-foreground (&optional next)
+  (declare (ignore next))
+  t)
+(defun terminate-session ())