sb!vm:*static-space-free-pointer*))
(eval-when (:compile-toplevel :execute)
- (sb!xc:defmacro def-c-var-frob (lisp-fun c-var-name)
- `(progn
- #!-sb-fluid (declaim (inline ,lisp-fun))
- (defun ,lisp-fun ()
- (sb!alien:extern-alien ,c-var-name (sb!alien:unsigned 32))))))
+ (sb!xc:defmacro def-c-var-fun (lisp-fun c-var-name)
+ `(defun ,lisp-fun ()
+ (sb!alien:extern-alien ,c-var-name (sb!alien:unsigned 32)))))
+#!-sb-fluid
+(declaim (inline current-dynamic-space-start))
+#!+gencgc
+(defun current-dynamic-space-start () sb!vm:dynamic-space-start)
#!-gencgc
-(progn
- ;; This is called once per PROFILEd function call, so it's worth a
- ;; little possible space cost to reduce its time cost.
- #!-sb-fluid
- (declaim (inline current-dynamic-space-start))
- (def-c-var-frob current-dynamic-space-start "current_dynamic_space"))
+(def-c-var-fun current-dynamic-space-start "current_dynamic_space")
#!-sb-fluid
-(declaim (inline dynamic-usage)) ; to reduce PROFILEd call overhead
+(declaim (inline dynamic-usage))
#!+gencgc
-(def-c-var-frob dynamic-usage "bytes_allocated")
+(def-c-var-fun dynamic-usage "bytes_allocated")
#!-gencgc
(defun dynamic-usage ()
(the (unsigned-byte 32)
\f
;;;; GC hooks
-(defvar *before-gc-hooks* nil ; actually initialized in cold init
- #!+sb-doc
- "A list of functions that are called before garbage collection occurs.
- The functions are run with interrupts disabled and all other threads
- paused. They should take no arguments.")
-
-(defvar *after-gc-hooks* nil ; actually initialized in cold init
- #!+sb-doc
- "A list of functions that are called after garbage collection occurs.
- The functions are run with interrupts disabled and all other threads
- paused. They should take no arguments.")
+(defvar *after-gc-hooks* nil
+ "Called after each garbage collection. In a multithreaded
+environment these hooks may run in any thread.")
;;;; The following specials are used to control when garbage
;;;; collection occurs.
\f
;;;; SUB-GC
-;;; This is used to carefully invoke hooks.
-(eval-when (:compile-toplevel :execute)
- (sb!xc:defmacro carefully-funcall (function &rest args)
- `(handler-case (funcall ,function ,@args)
- (error (cond)
- (warn "(FUNCALL ~S~{ ~S~}) lost:~%~A" ',function ',args cond)
- nil))))
-
;;; SUB-GC does a garbage collection. This is called from three places:
;;; (1) The C runtime will call here when it detects that we've consed
;;; enough to exceed the gc trigger threshold. This is done in
(defvar *already-in-gc*
(sb!thread:make-mutex :name "GC lock") "ID of thread running SUB-GC")
-(defun sub-gc (&key (gen 0) &aux (pre-gc-dynamic-usage (dynamic-usage)))
- (let ((me (sb!thread:current-thread-id)))
- (when (eql (sb!thread::mutex-value *already-in-gc*) me)
- (return-from sub-gc nil))
+(defun sub-gc (&key (gen 0))
+ (unless (eql (sb!thread:current-thread-id)
+ (sb!thread::mutex-value *already-in-gc*))
+ ;; With gencgc, unless *NEED-TO-COLLECT-GARBAGE* every allocation
+ ;; in this function triggers another gc, potentially exceeding
+ ;; maximum interrupt nesting.
(setf *need-to-collect-garbage* t)
(when (zerop *gc-inhibit*)
- (loop
- (sb!thread:with-mutex (*already-in-gc*)
- (unless *need-to-collect-garbage* (return-from sub-gc nil))
- (without-interrupts
- (gc-stop-the-world)
- (collect-garbage gen)
- (incf *n-bytes-freed-or-purified*
- (max 0 (- pre-gc-dynamic-usage (dynamic-usage))))
- (scrub-control-stack)
- (setf *need-to-collect-garbage* nil)
- (dolist (h *after-gc-hooks*) (carefully-funcall h))
- (gc-start-the-world))
- (sb!thread::reap-dead-threads))))))
+ (sb!thread:with-mutex (*already-in-gc*)
+ (let ((old-usage (dynamic-usage))
+ (new-usage 0))
+ (unsafe-clear-roots)
+ ;; We need to disable interrupts for GC, but we also want
+ ;; to run as little as possible without them.
+ (without-interrupts
+ (gc-stop-the-world)
+ (collect-garbage gen)
+ (setf *need-to-collect-garbage* nil
+ new-usage (dynamic-usage))
+ (gc-start-the-world))
+ ;; Interrupts re-enabled, but still inside the mutex.
+ ;; In a multithreaded environment the other threads will
+ ;; see *n-b-f-o-p* change a little late, but that's OK.
+ (let ((freed (- old-usage new-usage)))
+ ;; GENCGC occasionally reports negative here, but the
+ ;; current belief is that it is part of the normal order
+ ;; of things and not a bug.
+ (when (plusp freed)
+ (incf *n-bytes-freed-or-purified* freed)))
+ (sb!thread::reap-dead-threads)))
+ ;; Outside the mutex, these may cause another GC. FIXME: it can
+ ;; potentially exceed maximum interrupt nesting by triggering
+ ;; GCs.
+ (run-pending-finalizers)
+ (dolist (hook *after-gc-hooks*)
+ (handler-case
+ (funcall hook)
+ (error (c)
+ (warn "Error calling after GC hook ~S:~% ~S" hook c)))))))
;;; This is the user-advertised garbage collection function.
(defun gc (&key (gen 0) (full nil) &allow-other-keys)
generational garbage collectors, but is ignored in this implementation."
(sub-gc :gen (if full 6 gen)))
+(defun unsafe-clear-roots ()
+ ;; KLUDGE: Do things in an attempt to get rid of extra roots. Unsafe
+ ;; as having these cons more then we have space left leads to huge
+ ;; badness.
+ (scrub-control-stack)
+ ;; FIXME: CTYPE-OF-CACHE-CLEAR isn't thread-safe.
+ #!-sb-thread
+ (ctype-of-cache-clear))
+
\f
;;;; auxiliary functions
(sb!alien:unsigned 32))
val))
+;;; FIXME: Aren't these utterly wrong if called inside WITHOUT-GCING?
+;;; Unless something that works there too can be deviced this fact
+;;; should be documented.
(defun gc-on ()
#!+sb-doc
"Enable the garbage collector."
projects / sbcl.git / blobdiff