X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Fsysmacs.lisp;h=b0aeb172b67fad6c2c30f8defb0643eba1c6dd2d;hb=7a2a31f9407a7da9d26cf1bc91c302461823719f;hp=bcb82555a2fccde30c1a3ea614784a1f82bde9b5;hpb=7beac8a1fb3cfdeda0e168eb597a701951032270;p=sbcl.git diff --git a/src/code/sysmacs.lisp b/src/code/sysmacs.lisp index bcb8255..b0aeb17 100644 --- a/src/code/sysmacs.lisp +++ b/src/code/sysmacs.lisp @@ -11,41 +11,66 @@ (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 - (when (and (not *gc-inhibit*) - (or #!+sb-thread *stop-for-gc-pending* - *gc-pending*)) - (sb!unix::receive-pending-interrupt)))) - + "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)))))))) ;;; EOF-OR-LOSE is a useful macro that handles EOF. (defmacro eof-or-lose (stream eof-error-p eof-value) @@ -119,6 +144,9 @@ waits until gc is enabled in this thread." ;;; This macro sets up some local vars for use by the ;;; FAST-READ-CHAR macro within the enclosed lexical scope. The stream ;;; is assumed to be a ANSI-STREAM. +;;; +;;; KLUDGE: Some functions (e.g. ANSI-STREAM-READ-LINE) use these variables +;;; directly, instead of indirecting through FAST-READ-CHAR. (defmacro prepare-for-fast-read-char (stream &body forms) `(let* ((%frc-stream% ,stream) (%frc-method% (ansi-stream-in %frc-stream%)) @@ -134,54 +162,61 @@ waits until gc is enabled in this thread." `(setf (ansi-stream-in-index %frc-stream%) %frc-index%)) ;;; a macro with the same calling convention as READ-CHAR, to be used -;;; within the scope of a PREPARE-FOR-FAST-READ-CHAR +;;; 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))))))