fault, etc. In the absence of --lose-on-corruption a warning is
printed to stderr.
* optimization: slightly faster gc on multithreaded builds
+ * optimization: faster WITHOUT-GCING
* bug fix: real-time signals are not used anymore, so no more
hanging when the system wide real-time signal queue gets full.
;; *TYPE-SYSTEM-INITIALIZED-WHEN-BOUND* so that it doesn't need to
;; be explicitly set in order to be meaningful.
(setf *after-gc-hooks* nil
+ *in-without-gcing* nil
*gc-inhibit* t
*gc-pending* nil
#!+sb-thread *stop-for-gc-pending* #!+sb-thread nil
sb!debug:*stack-top-hint*
*handler-clusters*
*restart-clusters*
- *gc-inhibit* *gc-pending*
+ *in-without-gcing* *gc-inhibit* *gc-pending*
#!+sb-thread *stop-for-gc-pending*
*software-interrupt-vector* *load-verbose*
*load-print-stuff* *in-compilation-unit*
(declare (optimize (safety 0) (speed 3)))
(sb!vm::locked-symbol-global-value-add ',symbol-name ,delta)))
-(defvar *gc-inhibit*) ; initialized in cold init
+;;;; these are 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
,@body))
(if *gc-inhibit*
(,without-gcing-body)
- (without-interrupts
- ;; We need to disable interrupts before disabling GC, so that
- ;; signal handlers using locks don't accidentally try to grab
- ;; them with GC inhibited.
- ;;
- ;; It would be nice to implement this with just a single UWP, but
- ;; unfortunately it seems that it cannot be done: the naive
- ;; solution of binding both *INTERRUPTS-ENABLED* and
- ;; *GC-INHIBIT*, and checking for both pending GC and interrupts
- ;; in the cleanup breaks if we have a GC pending, but no
- ;; interrupts, and we receive an asynch unwind while checking for
- ;; the pending GC: we unwind before handling the pending GC, and
- ;; will be left running with further GCs blocked due to the GC
- ;; pending flag.
+ ;; 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 ((*gc-inhibit* t))
+ (let* ((*allow-with-interrupts* nil)
+ (*interrupts-enabled* nil)
+ (*gc-inhibit* t))
(,without-gcing-body))
- (when (or *gc-pending* #!+sb-thread *stop-for-gc-pending*)
+ ;; 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.
sb!unix::*allow-with-interrupts*
sb!unix::*interrupts-enabled*
sb!unix::*interrupt-pending*
+ *in-without-gcing*
*gc-inhibit*
*gc-pending*
#!-sb-thread
lose ("in pseudo atomic section\n");
}
+/* Are we leaving WITH-GCING and already running with interrupts
+ * enabled, without the protection of *GC-INHIBIT* T and there is gc
+ * (or stop for gc) pending, but we haven't trapped yet? */
+int
+in_leaving_without_gcing_race_p(struct thread *thread)
+{
+ return ((SymbolValue(IN_WITHOUT_GCING,thread) != NIL) &&
+ (SymbolValue(INTERRUPTS_ENABLED,thread) != NIL) &&
+ (SymbolValue(GC_INHIBIT,thread) == NIL) &&
+ ((SymbolValue(GC_PENDING,thread) != NIL)
+#if defined(LISP_FEATURE_SB_THREAD)
+ || (SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL)
+#endif
+ ));
+}
+
/* Check our baroque invariants. */
void
check_interrupt_context_or_lose(os_context_t *context)
#if defined(LISP_FEATURE_GENCGC) && !defined(LISP_FEATURE_PPC)
#if 0
int interrupts_enabled = (SymbolValue(INTERRUPTS_ENABLED,thread) != NIL);
+#endif
int gc_inhibit = (SymbolValue(GC_INHIBIT,thread) != NIL);
int gc_pending = (SymbolValue(GC_PENDING,thread) == T);
int pseudo_atomic_interrupted = get_pseudo_atomic_interrupted(thread);
-#endif
+ int in_race_p = in_leaving_without_gcing_race_p(thread);
/* In the time window between leaving the *INTERRUPTS-ENABLED* NIL
* section and trapping, a SIG_STOP_FOR_GC would see the next
* check fail, for this reason sig_stop_for_gc handler does not
* triggered, too. */
#if 0
if (interrupt_deferred_p)
- if (interrupts_enabled && !pseudo_atomic_interrupted)
+ if (!(!interrupts_enabled || pseudo_atomic_interrupted || in_race_p))
lose("Stray deferred interrupt.");
#endif
- /* Broken momentarily at the end of WITHOUT-GCING. */
#if 0
if (gc_pending)
- if (!(pseudo_atomic_interrupted || gc_inhibit))
+ if (!(pseudo_atomic_interrupted || gc_inhibit || in_race_p))
lose("GC_PENDING, but why?.");
#if defined(LISP_FEATURE_SB_THREAD)
{
int stop_for_gc_pending =
(SymbolValue(STOP_FOR_GC_PENDING,thread) != NIL);
if (stop_for_gc_pending)
- if (!(pseudo_atomic_interrupted || gc_inhibit))
+ if (!(pseudo_atomic_interrupted || gc_inhibit || in_race_p))
lose("STOP_FOR_GC_PENDING, but why?.");
}
#endif
/* If interrupts are disabled then INTERRUPT_PENDING is set and
* not PSEDUO_ATOMIC_INTERRUPTED. This is important for a pseudo
* atomic section inside a WITHOUT-INTERRUPTS.
+ *
+ * Also, if in_leaving_without_gcing_race_p then
+ * interrupt_handle_pending is going to be called soon, so
+ * stashing the signal away is safe.
*/
- if (SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) {
+ if ((SymbolValue(INTERRUPTS_ENABLED,thread) == NIL) ||
+ in_leaving_without_gcing_race_p(thread)) {
store_signal_data_for_later(data,handler,signal,info,context);
SetSymbolValue(INTERRUPT_PENDING, T,thread);
FSHOW_SIGNAL((stderr,
;;; checkins which aren't released. (And occasionally for internal
;;; versions, especially for internal versions off the main CVS
;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
-"1.0.25.31"
+"1.0.25.32"
projects / sbcl.git / commitdiff