X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Ftarget-thread.lisp;h=b8829629332145ac130dd0a93e00ce1a6bef8736;hb=11b388bac03fea3220e058eb93466bef7b66af75;hp=9b69d91115a90bacd3ce433ae06a134e181baf56;hpb=dcf5978d9d33098e868ae6eea28e1b310038c03d;p=sbcl.git

diff --git a/src/code/target-thread.lisp b/src/code/target-thread.lisp
index 9b69d91..b882962 100644
--- a/src/code/target-thread.lisp
+++ b/src/code/target-thread.lisp
@@ -1,91 +1,31 @@
+;;;; 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")
 
 ;;; FIXME it would be good to define what a thread id is or isn't (our
 ;;; current assumption is that it's a fixnum).  It so happens that on
 ;;; Linux it's a pid, but it might not be on posix thread implementations
 
-(sb!alien::define-alien-routine ("create_thread" %create-thread)
-     sb!alien:unsigned-long
-  (lisp-fun-address sb!alien:unsigned-long))
-
-(sb!alien::define-alien-routine "signal_thread_to_dequeue"
-    sb!alien:unsigned-int
-  (thread-pid sb!alien:unsigned-long))
-
-
-(defun make-thread (function)
-  (let ((real-function (coerce function 'function)))
-    (%create-thread
-     (sb!kernel:get-lisp-obj-address
-      (lambda ()
-	;; in time we'll move some of the binding presently done in C
-	;; here too
-	(let ((sb!kernel::*restart-clusters* nil)
-	      (sb!impl::*descriptor-handlers* nil); serve-event
-	      (sb!impl::*available-buffers* nil)) ;for fd-stream
-	  ;; can't use handling-end-of-the-world, because that flushes
-	  ;; output streams, and we don't necessarily have any (or we
-	  ;; could be sharing them)
-	  (sb!sys:enable-interrupt sb!unix:sigint :ignore)
-	  (sb!unix:unix-exit
-	   (catch 'sb!impl::%end-of-the-world 
-	     (with-simple-restart 
-		 (destroy-thread
-		  (format nil "~~@<Destroy this thread (~A)~~@:>"
-			  (current-thread-id)))
-	       (funcall real-function))
-	     0))))))))
-
-;;; Really, you don't want to use these: they'll get into trouble with
-;;; garbage collection.  Use a lock or a waitqueue instead
-(defun suspend-thread (thread-id)
-  (sb!unix:unix-kill thread-id sb!unix:sigstop))
-(defun resume-thread (thread-id)
-  (sb!unix:unix-kill thread-id sb!unix:sigcont))
-;;; Note warning about cleanup forms
-(defun destroy-thread (thread-id)
-  "Destroy the thread identified by THREAD-ID abruptly, without running cleanup forms"
-  (sb!unix:unix-kill thread-id sb!unix:sigterm)
-  ;; may have been stopped for some reason, so now wake it up to
-  ;; deliver the TERM
-  (sb!unix:unix-kill thread-id sb!unix:sigcont))
-
+(define-alien-routine ("create_thread" %create-thread)
+    unsigned-long
+  (lisp-fun-address unsigned-long))
 
-;;; a moderate degree of care is expected for use of interrupt-thread,
-;;; due to its nature: if you interrupt a thread that was holding
-;;; important locks then do something that turns out to need those
-;;; locks, you probably won't like the effect.  Used with thought
-;;; though, it's a good deal gentler than the last-resort functions above
-
-(defun interrupt-thread (thread function)
-  "Interrupt THREAD and make it run FUNCTION.  "
-  (sb!unix::syscall* ("interrupt_thread"
-		      sb!alien:unsigned-long  sb!alien:unsigned-long)
-		     thread
-		     thread (sb!kernel:get-lisp-obj-address
-			     (coerce function 'function))))
-(defun terminate-thread (thread-id)
-  "Terminate the thread identified by THREAD-ID, by causing it to run
-SB-EXT:QUIT - the usual cleanup forms will be evaluated"
-  (interrupt-thread thread-id 'sb!ext:quit))
-
-(declaim (inline current-thread-id))
-(defun current-thread-id ()
-  (logand 
-   (sb!sys:sap-int
-    (sb!vm::current-thread-offset-sap sb!vm::thread-pid-slot))
-   ;; KLUDGE pids are 16 bit really.  Avoid boxing the return value
-   (1- (ash 1 16))))
+(define-alien-routine "signal_thread_to_dequeue"
+    unsigned-int
+  (thread-id unsigned-long))
 
-;;;; iterate over the in-memory threads
+(define-alien-routine reap-dead-threads void)
 
-(defun mapcar-threads (function)
-  "Call FUNCTION once for each known thread, giving it the thread structure as argument"
-  (let ((function (coerce function 'function)))
-    (loop for thread = (alien-sap (extern-alien "all_threads" (* t)))
-	  then  (sb!sys:sap-ref-sap thread (* 4 sb!vm::thread-next-slot))
-	  until (sb!sys:sap= thread (sb!sys:int-sap 0))
-	  collect (funcall function thread))))
+(defvar *session* nil)
 
 ;;;; queues, locks 
 
@@ -118,7 +58,7 @@ SB-EXT:QUIT - the usual cleanup forms will be evaluated"
 (declaim (inline waitqueue-data-address mutex-value-address))
 
 (defstruct waitqueue
-  (name nil :type (or null simple-base-string))
+  (name nil :type (or null simple-string))
   (lock 0)
   (data nil))
 
@@ -153,6 +93,7 @@ SB-EXT:QUIT - the usual cleanup forms will be evaluated"
 (sb!alien:define-alien-routine
     "futex_wake" int (word unsigned-long) (n unsigned-long))
 
+
 ;;; this should only be called while holding the queue spinlock.
 ;;; it releases the spinlock before sleeping
 (defun wait-on-queue (queue &optional lock)
@@ -182,6 +123,9 @@ SB-EXT:QUIT - the usual cleanup forms will be evaluated"
 ;;; i suspect there may be a race still in this: the futex version requires
 ;;; the old mutex value before sleeping, so how do we get away without it
 (defun get-mutex (lock &optional new-value (wait-p t))
+  "Acquire LOCK, setting it to NEW-VALUE or some suitable default value 
+if NIL.  If WAIT-P is non-NIL and the lock is in use, sleep until it
+is available"
   (declare (type mutex lock) (optimize (speed 3)))
   (let ((pid (current-thread-id)))
     (unless new-value (setf new-value pid))
@@ -205,7 +149,8 @@ SB-EXT:QUIT - the usual cleanup forms will be evaluated"
   (let ((pid (current-thread-id))
 	old)
     (unless new-value (setf new-value pid))
-    (assert (not (eql new-value (mutex-value lock))))
+    (when (eql new-value (mutex-value lock))
+      (warn "recursive lock attempt ~S~%" lock))
     (loop
      (unless
 	 (setf old (sb!vm::%instance-set-conditional lock 4 nil new-value))
@@ -227,16 +172,6 @@ SB-EXT:QUIT - the usual cleanup forms will be evaluated"
   (setf (mutex-value lock) nil)
   (futex-wake (mutex-value-address lock) 1))
 
-
-(defmacro with-mutex ((mutex &key value (wait-p t))  &body body)
-  (with-unique-names (got)
-    `(let ((,got (get-mutex ,mutex ,value ,wait-p)))
-      (when ,got
-	(unwind-protect
-	     (progn ,@body)
-	  (release-mutex ,mutex))))))
-
-
 ;;;; condition variables
 
 (defun condition-wait (queue lock)
@@ -313,93 +248,252 @@ time we reacquire LOCK and return to the caller."
 (defun maybe-install-futex-functions ()
   #!+sb-futex
   (unless (zerop (extern-alien "linux_supports_futex" int))
-    (setf (fdefinition 'get-mutex) #'get-mutex/futex
-	  (fdefinition 'release-mutex) #'release-mutex/futex
-	  (fdefinition 'condition-wait) #'condition-wait/futex
-	  (fdefinition 'condition-broadcast) #'condition-broadcast/futex
-	  (fdefinition 'condition-notify) #'condition-notify/futex)
+    (sb!ext:without-package-locks
+      (setf (fdefinition 'get-mutex) #'get-mutex/futex
+            (fdefinition 'release-mutex) #'release-mutex/futex
+            (fdefinition 'condition-wait) #'condition-wait/futex
+            (fdefinition 'condition-broadcast) #'condition-broadcast/futex
+            (fdefinition 'condition-notify) #'condition-notify/futex))
     t))
 
-;;;; multiple independent listeners
+(defun make-thread (function)
+  (let* ((real-function (coerce function 'function))
+	 (tid
+	  (%create-thread
+	   (sb!kernel:get-lisp-obj-address
+	    (lambda ()
+	      ;; in time we'll move some of the binding presently done in C
+	      ;; here too
+	      (let ((sb!kernel::*restart-clusters* nil)
+		    (sb!kernel::*handler-clusters* nil)
+		    (sb!kernel::*condition-restarts* nil)
+		    (sb!impl::*descriptor-handlers* nil) ; serve-event
+		    (sb!impl::*available-buffers* nil)) ;for fd-stream
+		;; can't use handling-end-of-the-world, because that flushes
+		;; output streams, and we don't necessarily have any (or we
+		;; could be sharing them)
+		(sb!sys:enable-interrupt sb!unix:sigint :ignore)
+		(catch 'sb!impl::%end-of-the-world 
+		  (with-simple-restart 
+		      (destroy-thread
+		       (format nil "~~@<Destroy this thread (~A)~~@:>"
+			       (current-thread-id)))
+		    (funcall real-function))
+		  0))
+	      (values))))))
+    (with-mutex ((session-lock *session*))
+      (pushnew tid (session-threads *session*)))
+    tid))
 
-(defvar *session-lock* nil)
+;;; Really, you don't want to use these: they'll get into trouble with
+;;; garbage collection.  Use a lock or a waitqueue instead
+(defun suspend-thread (thread-id)
+  (sb!unix:unix-kill thread-id sb!unix:sigstop))
+(defun resume-thread (thread-id)
+  (sb!unix:unix-kill thread-id sb!unix:sigcont))
+;;; Note warning about cleanup forms
+(defun destroy-thread (thread-id)
+  "Destroy the thread identified by THREAD-ID abruptly, without running cleanup forms"
+  (sb!unix:unix-kill thread-id sb!unix:sigterm)
+  ;; may have been stopped for some reason, so now wake it up to
+  ;; deliver the TERM
+  (sb!unix:unix-kill thread-id sb!unix:sigcont))
 
-(defun make-listener-thread (tty-name)  
-  (assert (probe-file tty-name))
-  ;; FIXME probably still need to do some tty stuff to get signals
-  ;; delivered correctly.
-  ;; FIXME 
-  (let* ((in (sb!unix:unix-open (namestring tty-name) sb!unix:o_rdwr #o666))
-	 (out (sb!unix:unix-dup in))
-	 (err (sb!unix:unix-dup in)))
-    (labels ((thread-repl () 
-	       (sb!unix::unix-setsid)
-	       (let* ((*session-lock*
-		       (make-mutex :name (format nil "lock for ~A" tty-name)))
-		      (sb!impl::*stdin* 
-		       (sb!sys:make-fd-stream in :input t :buffering :line))
-		      (sb!impl::*stdout* 
-		       (sb!sys:make-fd-stream out :output t :buffering :line))
-		      (sb!impl::*stderr* 
-		       (sb!sys:make-fd-stream err :output t :buffering :line))
-		      (sb!impl::*tty* 
-		       (sb!sys:make-fd-stream err :input t :output t :buffering :line))
-		      (sb!impl::*descriptor-handlers* nil))
-		 (get-mutex *session-lock*)
-		 (sb!sys:enable-interrupt sb!unix:sigint #'sb!unix::sigint-handler)
-		 (unwind-protect
-		      (sb!impl::toplevel-repl nil)
-		   (sb!int:flush-standard-output-streams)))))
-      (make-thread #'thread-repl))))
-  
-;;;; job control
+     
+     
+
+;;; a moderate degree of care is expected for use of interrupt-thread,
+;;; due to its nature: if you interrupt a thread that was holding
+;;; important locks then do something that turns out to need those
+;;; locks, you probably won't like the effect.  Used with thought
+;;; though, it's a good deal gentler than the last-resort functions above
+
+(define-condition interrupt-thread-error (error)
+  ((thread :reader interrupt-thread-error-thread :initarg :thread)
+   (errno :reader interrupt-thread-error-errno :initarg :errno))
+  (:report (lambda (c s)
+	     (format s "interrupt thread ~A failed (~A: ~A)"
+		     (interrupt-thread-error-thread c)
+		     (interrupt-thread-error-errno c)
+		     (strerror (interrupt-thread-error-errno c))))))
+
+(defun interrupt-thread (thread function)
+  "Interrupt THREAD and make it run FUNCTION."
+  (let ((function (coerce function 'function)))
+    (sb!sys:with-pinned-objects 
+     (function)
+     (multiple-value-bind (res err)
+	 (sb!unix::syscall ("interrupt_thread"
+			    sb!alien:unsigned-long  sb!alien:unsigned-long)
+			   thread
+			   thread 
+			   (sb!kernel:get-lisp-obj-address function))
+       (unless res
+	 (error 'interrupt-thread-error :thread thread :errno err))))))
+
+
+(defun terminate-thread (thread-id)
+  "Terminate the thread identified by THREAD-ID, by causing it to run
+SB-EXT:QUIT - the usual cleanup forms will be evaluated"
+  (interrupt-thread thread-id 'sb!ext:quit))
+
+(declaim (inline current-thread-id))
+(defun current-thread-id ()
+  (logand 
+   (sb!sys:sap-int
+    (sb!vm::current-thread-offset-sap sb!vm::thread-pid-slot))
+   ;; KLUDGE pids are 16 bit really.  Avoid boxing the return value
+   (1- (ash 1 16))))
 
+;;;; iterate over the in-memory threads
 
-(defvar *interactive-threads-lock* 
-  (make-mutex :name "*interactive-threads* lock"))
-(defvar *interactive-threads* nil)
-(defvar *interactive-threads-queue*
-  (make-waitqueue :name "All threads that need the terminal.  First ID on this list is running, the others are waiting"))
+(defun mapcar-threads (function)
+  "Call FUNCTION once for each known thread, giving it the thread structure as argument"
+  (let ((function (coerce function 'function)))
+    (loop for thread = (alien-sap (extern-alien "all_threads" (* t)))
+	  then  (sb!sys:sap-ref-sap thread (* 4 sb!vm::thread-next-slot))
+	  until (sb!sys:sap= thread (sb!sys:int-sap 0))
+	  collect (funcall function thread))))
+
+(defun thread-sap-from-id (id)
+  (let ((thread (alien-sap (extern-alien "all_threads" (* t)))))
+    (loop 
+     (when (sb!sys:sap= thread (sb!sys:int-sap 0)) (return nil))
+     (let ((pid (sb!sys:sap-ref-32 thread (* 4 sb!vm::thread-pid-slot))))
+       (when (= pid id) (return thread))
+       (setf thread (sb!sys:sap-ref-sap thread (* 4 sb!vm::thread-next-slot)))))))
+
+;;; internal use only.  If you think you need to use this, either you
+;;; are an SBCL developer, are doing something that you should discuss
+;;; with an SBCL developer first, or are doing something that you
+;;; should probably discuss with a professional psychiatrist first
+(defun symbol-value-in-thread (symbol thread-id)
+  (let ((thread (thread-sap-from-id thread-id)))
+    (when thread
+      (let* ((index (sb!vm::symbol-tls-index symbol))
+	     (tl-val (sb!sys:sap-ref-32 thread (* 4 index))))
+	(if (eql tl-val sb!vm::unbound-marker-widetag)
+	    (sb!vm::symbol-global-value symbol)
+	    (sb!kernel:make-lisp-obj tl-val))))))
+
+;;;; job control, independent listeners
+
+(defstruct session 
+  (lock (make-mutex))
+  (threads nil)
+  (interactive-threads nil)
+  (interactive-threads-queue (make-waitqueue)))
+
+(defun new-session ()
+  (let ((tid (current-thread-id)))
+    (make-session :threads (list tid)
+		  :interactive-threads (list tid))))
 
 (defun init-job-control ()
-  (with-mutex (*interactive-threads-lock*)
-    (setf *interactive-threads* (list (current-thread-id)))
-    (return-from init-job-control t)))
+  (setf *session* (new-session)))
+
+(defun %delete-thread-from-session (tid session)
+  (with-mutex ((session-lock session))
+    (setf (session-threads session)
+	  (delete tid (session-threads session))
+	  (session-interactive-threads session)
+	  (delete tid (session-interactive-threads session)))))
+
+(defun call-with-new-session (fn)
+  (%delete-thread-from-session (current-thread-id) *session*)
+  (let ((*session* (new-session)))  (funcall fn)))
+
+(defmacro with-new-session (args &body forms)
+  (declare (ignore args))		;for extensibility
+  (sb!int:with-unique-names (fb-name)
+    `(labels ((,fb-name () ,@forms))
+      (call-with-new-session (function ,fb-name)))))
+
+;;; Remove thread id TID from its session, if it has one.  This is
+;;; called from C reap_dead_threads() so is run in the context of
+;;; whichever thread called that (usually after a GC), which may not have 
+;;; any meaningful parent/child/sibling relationship with the dead thread
+(defun handle-thread-exit (tid)
+  (let ((session (symbol-value-in-thread '*session* tid)))
+    (and session (%delete-thread-from-session tid session))))
+  
+(defun terminate-session ()
+  "Kill all threads in session except for this one.  Does nothing if current
+thread is not the foreground thread"
+  (reap-dead-threads)
+  (let* ((tid (current-thread-id))
+	 (to-kill
+	  (with-mutex ((session-lock *session*))
+	    (and (eql tid (car (session-interactive-threads *session*)))
+		 (session-threads *session*)))))
+    ;; do the kill after dropping the mutex; unwind forms in dying
+    ;; threads may want to do session things
+    (dolist (p to-kill)
+      (unless (eql p tid) (terminate-thread p)))))
 
 ;;; called from top of invoke-debugger
 (defun debugger-wait-until-foreground-thread (stream)
   "Returns T if thread had been running in background, NIL if it was
 interactive."
+  (declare (ignore stream))
   (prog1
-      (with-mutex (*interactive-threads-lock*)
-	(not (member (current-thread-id) *interactive-threads*)))
+      (with-mutex ((session-lock *session*))
+	(not (member (current-thread-id) 
+		     (session-interactive-threads *session*))))
     (get-foreground)))
 
-(defun thread-repl-prompt-fun (out-stream)
-  (get-foreground)
-  (let ((stopped-threads (cdr *interactive-threads*)))
-    (when stopped-threads
-      (format out-stream "~{~&Thread ~A suspended~}~%" stopped-threads))
-    (sb!impl::repl-prompt-fun out-stream)))
 
 (defun get-foreground ()
-  (loop
-   (with-mutex (*interactive-threads-lock*)
-     (let ((tid (current-thread-id)))
-       (when (eql (car *interactive-threads*) tid)
-	 (sb!sys:enable-interrupt sb!unix:sigint #'sb!unix::sigint-handler)
-	 (return-from get-foreground t))
-       (unless (member tid *interactive-threads*)
-	 (setf (cdr (last *interactive-threads*)) (list tid)))
-       (condition-wait
-	*interactive-threads-queue* *interactive-threads-lock* )))))
+  (let ((was-foreground t))
+    (loop
+     (with-mutex ((session-lock *session*))
+       (let ((tid (current-thread-id))
+	     (int-t (session-interactive-threads *session*)))
+	 (when (eql (car int-t) tid)
+	   (unless was-foreground
+	     (format *query-io* "Resuming thread ~A~%" tid))
+	   (sb!sys:enable-interrupt sb!unix:sigint #'sb!unix::sigint-handler)
+	   (return-from get-foreground t))
+	 (setf was-foreground nil)
+	 (unless (member tid int-t)
+	   (setf (cdr (last int-t))
+		 (list tid)))
+	 (condition-wait
+	  (session-interactive-threads-queue *session*)
+	  (session-lock *session*)))))))
 
 (defun release-foreground (&optional next)
   "Background this thread.  If NEXT is supplied, arrange for it to have the foreground next"
-  (with-mutex (*interactive-threads-lock*)
+  (with-mutex ((session-lock *session*))
     (let ((tid (current-thread-id)))
-      (setf *interactive-threads* (delete tid *interactive-threads*))
+      (setf (session-interactive-threads *session*)
+	    (delete tid (session-interactive-threads *session*)))
       (sb!sys:enable-interrupt sb!unix:sigint :ignore)
-      (when next (setf *interactive-threads*
-		       (list* next (delete next *interactive-threads*))))
-      (condition-broadcast *interactive-threads-queue*))))
\ No newline at end of file
+      (when next 
+	(setf (session-interactive-threads *session*)
+	      (list* next 
+		     (delete next (session-interactive-threads *session*)))))
+      (condition-broadcast (session-interactive-threads-queue *session*)))))
+
+(defun make-listener-thread (tty-name)  
+  (assert (probe-file tty-name))
+  (let* ((in (sb!unix:unix-open (namestring tty-name) sb!unix:o_rdwr #o666))
+	 (out (sb!unix:unix-dup in))
+	 (err (sb!unix:unix-dup in)))
+    (labels ((thread-repl () 
+	       (sb!unix::unix-setsid)
+	       (let* ((sb!impl::*stdin* 
+		       (sb!sys:make-fd-stream in :input t :buffering :line))
+		      (sb!impl::*stdout* 
+		       (sb!sys:make-fd-stream out :output t :buffering :line))
+		      (sb!impl::*stderr* 
+		       (sb!sys:make-fd-stream err :output t :buffering :line))
+		      (sb!impl::*tty* 
+		       (sb!sys:make-fd-stream err :input t :output t :buffering :line))
+		      (sb!impl::*descriptor-handlers* nil))
+		 (with-new-session ()
+		   (sb!sys:enable-interrupt sb!unix:sigint #'sb!unix::sigint-handler)
+		   (unwind-protect
+			(sb!impl::toplevel-repl nil)
+		     (sb!int:flush-standard-output-streams))))))
+      (make-thread #'thread-repl))))