[Sbcl-commits] CVS: sbcl/src/code gc.lisp,1.51,1.51.2.1

[Daniel B. <da...@us...>]

Update of /cvsroot/sbcl/sbcl/src/code
In directory sc8-pr-cvs1:/tmp/cvs-serv25804/src/code

Modified Files:
      Tag: atropos-branch
	gc.lisp 
Log Message:
0.8.3.95.atropos.2
	Rewrote the strange locking stuff in SUB-GC so that I can
	understand it again: as a side effect, my newest thread/gc
	torture test works again

	OTOH, the final test in threads.impure.lisp was once observed
	to break with this code, but who's to know if that's new?




Index: gc.lisp
===================================================================
RCS file: /cvsroot/sbcl/sbcl/src/code/gc.lisp,v
retrieving revision 1.51
retrieving revision 1.51.2.1
diff -u -d -r1.51 -r1.51.2.1
--- gc.lisp	29 Sep 2003 15:35:30 -0000	1.51
+++ gc.lisp	30 Sep 2003 15:49:11 -0000	1.51.2.1
@@ -237,25 +237,21 @@
 (defvar *gc-mutex* (sb!thread:make-mutex :name "GC Mutex"))
 
 (defun sub-gc (&key (gen 0) &aux (pre-gc-dynamic-usage (dynamic-usage)))
-  (when *already-in-gc* (return-from sub-gc nil))
-  (setf *need-to-collect-garbage* t)
-  (when (zerop *gc-inhibit*)
-    (sb!thread:with-recursive-lock (*gc-mutex*)
-      (let ((*already-in-gc* t))
-	(without-interrupts
-	 (gc-stop-the-world)
-	 #+nil
-	 (dolist (h *before-gc-hooks*)
-	   (carefully-funcall h))
-	 (collect-garbage gen)
-	 (incf *n-bytes-freed-or-purified*
-	       (max 0 (- pre-gc-dynamic-usage (dynamic-usage))))
-	 (setf *need-to-collect-garbage* nil)
-
-	 (gc-start-the-world)))
-      (scrub-control-stack))
-    (dolist (h *after-gc-hooks*)
-      (carefully-funcall h)))
+  ;; catch attempts to gc recursively or during post-hooks and ignore them
+  (when (sb!thread::mutex-value *gc-mutex*)  (return-from sub-gc nil))
+  (sb!thread:with-mutex (*gc-mutex* :wait-p nil)
+    (setf *need-to-collect-garbage* t)
+    (when (zerop *gc-inhibit*)
+      (without-interrupts
+       (gc-stop-the-world)
+       (collect-garbage gen)
+       (incf *n-bytes-freed-or-purified*
+	     (max 0 (- pre-gc-dynamic-usage (dynamic-usage))))
+       (setf *need-to-collect-garbage* nil)
+       (gc-start-the-world))
+      (scrub-control-stack)
+      (setf *need-to-collect-garbage* nil)
+      (dolist (h *after-gc-hooks*) (carefully-funcall h))))
   (values))