X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Fsysmacs.lisp;h=f9970c6abffcfc46e966a3b59647342a43196bdf;hb=77d7fddb855305e783c100bfe9b6b46bdb05e4b6;hp=3556bc1c782440eeda9cf6da1af97b9da854a724;hpb=dcf8b8ccc1e15a5c1c6aba00204b7d3a81827acc;p=sbcl.git

diff --git a/src/code/sysmacs.lisp b/src/code/sysmacs.lisp
index 3556bc1..f9970c6 100644
--- a/src/code/sysmacs.lisp
+++ b/src/code/sysmacs.lisp
@@ -11,24 +11,19 @@
 
 (in-package "SB!IMPL")
 
-(defmacro atomic-incf/symbol (symbol-name &optional (delta 1))
-  #!-sb-thread
-  `(incf ,symbol-name ,delta)
-  #!+sb-thread
-  `(locally
-    (declare (optimize (safety 0) (speed 3)))
-    (sb!vm::locked-symbol-global-value-add ',symbol-name ,delta)))
+;;;; these are initialized in cold init
 
-(defvar *gc-inhibit*) ; initialized in cold init
+(defvar *in-without-gcing*)
+(defvar *gc-inhibit*)
 
 ;;; When the dynamic usage increases beyond this amount, the system
 ;;; notes that a garbage collection needs to occur by setting
 ;;; *GC-PENDING* to T. It starts out as NIL meaning nobody has figured
 ;;; out what it should be yet.
-(defvar *gc-pending* nil)
+(defvar *gc-pending*)
 
 #!+sb-thread
-(defvar *stop-for-gc-pending* nil)
+(defvar *stop-for-gc-pending*)
 
 (defmacro without-gcing (&body body)
   #!+sb-doc
@@ -48,13 +43,27 @@ stopped for GC while T2 is waiting for the lock inside WITHOUT-GCING the
 system will be deadlocked. Since SBCL does not currently document its internal
 locks, application code can never be certain that this invariant is
 maintained."
-  `(unwind-protect
-        (without-interrupts
-          (let ((*gc-inhibit* t))
-            ,@body))
-     ;; the test is racy, but it can err only on the overeager side
-     (sb!kernel::maybe-handle-pending-gc)))
-
+  (with-unique-names (without-gcing-body)
+    `(flet ((,without-gcing-body ()
+              ,@body))
+       (if *gc-inhibit*
+           (,without-gcing-body)
+           ;; We need to disable interrupts before disabling GC, so
+           ;; that signal handlers using locks don't accidentally try
+           ;; to grab them with GC inhibited.
+           (let ((*in-without-gcing* t))
+             (unwind-protect
+                  (let* ((*allow-with-interrupts* nil)
+                         (*interrupts-enabled* nil)
+                         (*gc-inhibit* t))
+                    (,without-gcing-body))
+               ;; This is not racy becuase maybe_defer_handler
+               ;; defers signals if *GC-INHIBIT* is NIL but there
+               ;; is a pending gc or stop-for-gc.
+               (when (or *interrupt-pending*
+                         *gc-pending*
+                         #!+sb-thread *stop-for-gc-pending*)
+                 (sb!unix::receive-pending-interrupt))))))))
 
 ;;; EOF-OR-LOSE is a useful macro that handles EOF.
 (defmacro eof-or-lose (stream eof-error-p eof-value)
@@ -149,14 +158,19 @@ maintained."
 ;;; within the scope of a PREPARE-FOR-FAST-READ-CHAR.
 (defmacro fast-read-char (&optional (eof-error-p t) (eof-value ()))
   `(cond
-    ((not %frc-buffer%)
-     (funcall %frc-method% %frc-stream% ,eof-error-p ,eof-value))
-    ((= %frc-index% +ansi-stream-in-buffer-length+)
-     (prog1 (fast-read-char-refill %frc-stream% ,eof-error-p ,eof-value)
-            (setq %frc-index% (ansi-stream-in-index %frc-stream%))))
-    (t
-     (prog1 (aref %frc-buffer% %frc-index%)
-            (incf %frc-index%)))))
+     ((not %frc-buffer%)
+      (funcall %frc-method% %frc-stream% ,eof-error-p ,eof-value))
+     ((= %frc-index% +ansi-stream-in-buffer-length+)
+      (multiple-value-bind (eof-p index-or-value)
+          (fast-read-char-refill %frc-stream% ,eof-error-p ,eof-value)
+        (if eof-p
+            index-or-value
+            (progn
+              (setq %frc-index% (1+ index-or-value))
+              (aref %frc-buffer% index-or-value)))))
+     (t
+      (prog1 (aref %frc-buffer% %frc-index%)
+        (incf %frc-index%)))))
 
 ;;;; And these for the fasloader...