(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*)
+
+;;; This one is initialized by the runtime, at thread creation. On
+;;; non-x86oid gencgc targets, this is a per-thread list of objects
+;;; which must not be moved during GC. It is frobbed by the code for
+;;; with-pinned-objects in src/compiler/target/macros.lisp.
+#!+(and gencgc (not (or x86 x86-64)))
+(defvar sb!vm::*pinned-objects*)
(defmacro without-gcing (&body body)
#!+sb-doc
- "Executes the forms in the body without doing a garbage
-collection. It inhibits both automatically and explicitly triggered
-gcs. Finally, upon leaving the BODY if gc is not inhibited it runs the
-pending gc. Similarly, if gc is triggered in another thread then it
-waits until gc is enabled in this thread."
- `(unwind-protect
- (let ((*gc-inhibit* t))
- ,@body)
- ;; the test is racy, but it can err only on the overeager side
- (sb!kernel::maybe-handle-pending-gc)))
-
+ "Executes the forms in the body without doing a garbage collection. It
+inhibits both automatically and explicitly triggered collections. Finally,
+upon leaving the BODY if gc is not inhibited it runs the pending gc.
+Similarly, if gc is triggered in another thread then it waits until gc is
+enabled in this thread.
+
+Implies SB-SYS:WITHOUT-INTERRUPTS for BODY, and causes any nested
+SB-SYS:WITH-INTERRUPTS to signal a warning during execution of the BODY.
+
+Should be used with great care, and not at all in multithreaded application
+code: Any locks that are ever acquired while GC is inhibited need to be always
+held with GC inhibited to prevent deadlocks: if T1 holds the lock and is
+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."
+ (with-unique-names (without-gcing-body)
+ `(dx-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))))))))
\f
;;; EOF-OR-LOSE is a useful macro that handles EOF.
(defmacro eof-or-lose (stream eof-error-p eof-value)
;;; 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...
;;; Just like PREPARE-FOR-FAST-READ-CHAR except that we get the BIN
;;; method. The stream is assumed to be a ANSI-STREAM.
;;;
-;;; KLUDGE: It seems weird to have to remember to explicitly call
-;;; DONE-WITH-FAST-READ-BYTE at the end of this, given that we're
-;;; already wrapping the stuff inside in a block. Why not rename this
-;;; macro to WITH-FAST-READ-BYTE, do the DONE-WITH-FAST-READ-BYTE stuff
-;;; automatically at the end of the block, and eliminate
-;;; DONE-WITH-FAST-READ-BYTE as a separate entity? (and similarly
-;;; for the FAST-READ-CHAR stuff) -- WHN 19990825
-(defmacro prepare-for-fast-read-byte (stream &body forms)
- `(let* ((%frc-stream% ,stream)
- (%frc-method% (ansi-stream-bin %frc-stream%))
- (%frc-buffer% (ansi-stream-in-buffer %frc-stream%))
- (%frc-index% (ansi-stream-in-index %frc-stream%)))
- (declare (type index %frc-index%)
- (type ansi-stream %frc-stream%))
- ,@forms))
-
-;;; Similar to fast-read-char, but we use a different refill routine & don't
-;;; convert to characters. If ANY-TYPE is true, then this can be used on any
-;;; integer streams, and we don't assert the result type.
-(defmacro fast-read-byte (&optional (eof-error-p t) (eof-value ()) any-type)
- ;; KLUDGE: should use ONCE-ONLY on EOF-ERROR-P and EOF-VALUE -- WHN 19990825
- `(truly-the
- ,(if (and (eq eof-error-p t) (not any-type)) '(unsigned-byte 8) t)
- (cond
- ((not %frc-buffer%)
- (funcall %frc-method% %frc-stream% ,eof-error-p ,eof-value))
- ((= %frc-index% +ansi-stream-in-buffer-length+)
- (prog1 (fast-read-byte-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%))))))
-(defmacro done-with-fast-read-byte ()
- `(done-with-fast-read-char))
+;;; FIXME: Refactor PREPARE-FOR-FAST-READ-CHAR into similar shape.
+(defmacro with-fast-read-byte ((type stream &optional (eof-error-p t) eof-value)
+ &body body)
+ (aver (or (eq t eof-error-p) (eq t type)))
+ (with-unique-names (f-stream f-method f-buffer f-index eof-p eof-val)
+ `(let* ((,f-stream ,stream)
+ (,eof-p ,eof-error-p)
+ (,eof-val ,eof-value)
+ (,f-method (ansi-stream-bin ,f-stream))
+ (,f-buffer (ansi-stream-in-buffer ,f-stream))
+ (,f-index (ansi-stream-in-index ,f-stream)))
+ (declare (type ansi-stream ,f-stream)
+ (type index ,f-index))
+ (declare (disable-package-locks fast-read-byte))
+ (flet ((fast-read-byte ()
+ (,@(cond ((equal '(unsigned-byte 8) type)
+ ;; KLUDGE: For some reason I haven't tracked down
+ ;; this makes a difference even in given the TRULY-THE.
+ `(logand #xff))
+ (t
+ `(identity)))
+ (truly-the ,type
+ (cond
+ ((not ,f-buffer)
+ (funcall ,f-method ,f-stream ,eof-p ,eof-val))
+ ((= ,f-index +ansi-stream-in-buffer-length+)
+ (prog1 (fast-read-byte-refill ,f-stream ,eof-p ,eof-val)
+ (setq ,f-index (ansi-stream-in-index ,f-stream))))
+ (t
+ (prog1 (aref ,f-buffer ,f-index)
+ (incf ,f-index))))))))
+ (declare (inline fast-read-byte))
+ (declare (enable-package-locks read-byte))
+ (unwind-protect
+ (locally ,@body)
+ (setf (ansi-stream-in-index ,f-stream) ,f-index))))))
projects / sbcl.git / blobdiff