(defvar *all-threads-lock* (make-mutex :name "all threads lock"))
(defmacro with-all-threads-lock (&body body)
- #!-sb-thread
- `(locally ,@body)
- #!+sb-thread
- `(without-interrupts
- (with-mutex (*all-threads-lock*)
- ,@body)))
+ `(call-with-system-mutex (lambda () ,@body) *all-threads-lock*))
(defun list-all-threads ()
#!+sb-doc
(declaim (inline %lutex-init %lutex-wait %lutex-wake
%lutex-lock %lutex-unlock))
- (sb!alien:define-alien-routine ("lutex_init" %lutex-init)
+ (define-alien-routine ("lutex_init" %lutex-init)
int (lutex unsigned-long))
- (sb!alien:define-alien-routine ("lutex_wait" %lutex-wait)
+ (define-alien-routine ("lutex_wait" %lutex-wait)
int (queue-lutex unsigned-long) (mutex-lutex unsigned-long))
- (sb!alien:define-alien-routine ("lutex_wake" %lutex-wake)
+ (define-alien-routine ("lutex_wake" %lutex-wake)
int (lutex unsigned-long) (n int))
- (sb!alien:define-alien-routine ("lutex_lock" %lutex-lock)
+ (define-alien-routine ("lutex_lock" %lutex-lock)
int (lutex unsigned-long))
- (sb!alien:define-alien-routine ("lutex_trylock" %lutex-trylock)
+ (define-alien-routine ("lutex_trylock" %lutex-trylock)
int (lutex unsigned-long))
- (sb!alien:define-alien-routine ("lutex_unlock" %lutex-unlock)
+ (define-alien-routine ("lutex_unlock" %lutex-unlock)
int (lutex unsigned-long))
- (sb!alien:define-alien-routine ("lutex_destroy" %lutex-destroy)
+ (define-alien-routine ("lutex_destroy" %lutex-destroy)
int (lutex unsigned-long))
;; FIXME: Defining a whole bunch of alien-type machinery just for
#!-sb-lutex
(progn
- (declaim (inline futex-wait futex-wake))
+ (declaim (inline futex-wait %futex-wait futex-wake))
- (sb!alien:define-alien-routine "futex_wait"
- int (word unsigned-long) (old-value unsigned-long))
+ (define-alien-routine ("futex_wait" %futex-wait)
+ int (word unsigned-long) (old-value unsigned-long)
+ (to-sec long) (to-usec unsigned-long))
- (sb!alien:define-alien-routine "futex_wake"
+ (defun futex-wait (word old to-sec to-usec)
+ (with-interrupts
+ (%futex-wait word old to-sec to-usec)))
+
+ (define-alien-routine "futex_wake"
int (word unsigned-long) (n unsigned-long))))
;;; used by debug-int.lisp to access interrupt contexts
(sb!vm::current-thread-offset-sap n))
;;;; spinlocks
-#!+sb-thread
-(define-structure-slot-compare-and-exchange
- compare-and-exchange-spinlock-value
+(define-structure-slot-compare-and-swap
+ compare-and-swap-spinlock-value
:structure spinlock
:slot value)
(declaim (inline get-spinlock release-spinlock))
+;; Should always be called with interrupts disabled.
(defun get-spinlock (spinlock)
- (declare (optimize (speed 3) (safety 0))
- #!-sb-thread
- (ignore spinlock))
- ;; %instance-set-conditional can test for 0 (which is a fixnum) and
- ;; store any value
- #!+sb-thread
- (loop until
- (eql 0 (compare-and-exchange-spinlock-value spinlock 0 1)))
- t)
+ (declare (optimize (speed 3) (safety 0)))
+ (let* ((new *current-thread*)
+ (old (compare-and-swap-spinlock-value spinlock nil new)))
+ (when old
+ (when (eq old new)
+ (error "Recursive lock attempt on ~S." spinlock))
+ #!+sb-thread
+ (flet ((cas ()
+ (unless (compare-and-swap-spinlock-value spinlock nil new)
+ (return-from get-spinlock t))))
+ (if (and (not *interrupts-enabled*) *allow-with-interrupts*)
+ ;; If interrupts are enabled, but we are allowed to enabled them,
+ ;; check for pending interrupts every once in a while.
+ (loop
+ (loop repeat 128 do (cas)) ; 128 is arbitrary here
+ (sb!unix::%check-interrupts))
+ (loop (cas)))))
+ t))
(defun release-spinlock (spinlock)
- (declare (optimize (speed 3) (safety 0))
- #!-sb-thread (ignore spinlock))
- ;; %instance-set-conditional cannot compare arbitrary objects
- ;; meaningfully, so (compare-and-exchange-spinlock-value our-value 0)
- ;; does not work for bignum thread ids.
- #!+sb-thread
- (setf (spinlock-value spinlock) 0)
+ (declare (optimize (speed 3) (safety 0)))
+ (setf (spinlock-value spinlock) nil)
nil)
;;;; mutexes
(define-structure-slot-addressor mutex-value-address
:structure mutex
:slot value)
- (define-structure-slot-compare-and-exchange
- compare-and-exchange-mutex-value
+ (define-structure-slot-compare-and-swap
+ compare-and-swap-mutex-value
:structure mutex
:slot value))
-(defun get-mutex (mutex &optional (new-value *current-thread*) (wait-p t))
+(defun get-mutex (mutex &optional (new-value *current-thread*) (waitp t))
#!+sb-doc
- "Acquire MUTEX, setting it to NEW-VALUE or some suitable default
-value if NIL. If WAIT-P is non-NIL and the mutex is in use, sleep
-until it is available."
+ "Acquire MUTEX, setting it to NEW-VALUE or some suitable default value if
+NIL. If WAITP is non-NIL and the mutex is in use, sleep until it is available."
(declare (type mutex mutex) (optimize (speed 3)))
(/show0 "Entering GET-MUTEX")
(unless new-value
(setq new-value *current-thread*))
#!-sb-thread
- (let ((old-value (mutex-value mutex)))
- (when (and old-value wait-p)
- (error "In unithread mode, mutex ~S was requested with WAIT-P ~S and ~
+ (let ((old (mutex-value mutex)))
+ (when (and old waitp)
+ (error "In unithread mode, mutex ~S was requested with WAITP ~S and ~
new-value ~S, but has already been acquired (with value ~S)."
- mutex wait-p new-value old-value))
+ mutex waitp new-value old))
(setf (mutex-value mutex) new-value)
t)
#!+sb-thread
(format *debug-io* "Thread: ~A~%" *current-thread*)
(sb!debug:backtrace most-positive-fixnum *debug-io*)
(force-output *debug-io*))
+ ;; FIXME: Lutexes do not currently support deadlines, as at least
+ ;; on Darwin pthread_foo_timedbar functions are not supported:
+ ;; this means that we probably need to use the Carbon multiprocessing
+ ;; functions on Darwin.
+ ;;
+ ;; FIXME: This is definitely not interrupt safe: what happens if
+ ;; we get hit (1) during the lutex calls (ok, they may be safe,
+ ;; but has that been checked?) (2) after the lutex call, but
+ ;; before setting the mutex value.
#!+sb-lutex
(when (zerop (with-lutex-address (lutex (mutex-lutex mutex))
- (if wait-p
- (%lutex-lock lutex)
+ (if waitp
+ (with-interrupts (%lutex-lock lutex))
(%lutex-trylock lutex))))
(setf (mutex-value mutex) new-value))
#!-sb-lutex
(let (old)
- (loop
- (unless
- (setf old
- (compare-and-exchange-mutex-value mutex nil new-value))
- (return t))
- (unless wait-p (return nil))
- (with-pinned-objects (mutex old)
- (futex-wait (mutex-value-address mutex)
- (get-lisp-obj-address old)))))))
+ (when (and (setf old (compare-and-swap-mutex-value mutex nil new-value))
+ waitp)
+ (loop while old
+ do (multiple-value-bind (to-sec to-usec) (decode-timeout nil)
+ (when (= 1 (with-pinned-objects (mutex old)
+ (futex-wait (mutex-value-address mutex)
+ (get-lisp-obj-address old)
+ (or to-sec -1)
+ (or to-usec 0))))
+ (signal-deadline)))
+ (setf old (compare-and-swap-mutex-value mutex nil new-value))))
+ (not old))))
(defun release-mutex (mutex)
#!+sb-doc
(/show0 "CONDITION-WAITing")
#!+sb-lutex
(progn
+ ;; FIXME: This doesn't look interrupt safe!
(setf (mutex-value mutex) nil)
(with-lutex-address (queue-lutex-address (waitqueue-lutex queue))
(with-lutex-address (mutex-lutex-address (mutex-lutex mutex))
#!-sb-lutex
(unwind-protect
(let ((me *current-thread*))
- ;; XXX we should do something to ensure that the result of this setf
- ;; is visible to all CPUs
+ ;; FIXME: should we do something to ensure that the result
+ ;; of this setf is visible to all CPUs?
(setf (waitqueue-data queue) me)
(release-mutex mutex)
;; Now we go to sleep using futex-wait. If anyone else
;; manages to grab MUTEX and call CONDITION-NOTIFY during
;; this comment, it will change queue->data, and so
;; futex-wait returns immediately instead of sleeping.
- ;; Ergo, no lost wakeup
- (with-pinned-objects (queue me)
- (futex-wait (waitqueue-data-address queue)
- (get-lisp-obj-address me))))
+ ;; Ergo, no lost wakeup. We may get spurious wakeups,
+ ;; but that's ok.
+ (multiple-value-bind (to-sec to-usec) (decode-timeout nil)
+ (when (= 1 (with-pinned-objects (queue me)
+ (futex-wait (waitqueue-data-address queue)
+ (get-lisp-obj-address me)
+ (or to-sec -1) ;; our way if saying "no timeout"
+ (or to-usec 0))))
+ (signal-deadline))))
;; If we are interrupted while waiting, we should do these things
;; before returning. Ideally, in the case of an unhandled signal,
;; we should do them before entering the debugger, but this is
;;; funny situations (like getting a sigint while holding the session
;;; lock) occur
(defmacro with-session-lock ((session) &body body)
- #!-sb-thread (declare (ignore session))
- #!-sb-thread
- `(locally ,@body)
- #!+sb-thread
- `(without-interrupts
- (with-mutex ((session-lock ,session))
- ,@body)))
+ `(call-with-system-mutex (lambda () ,@body) (session-lock ,session)))
(defun new-session ()
(make-session :threads (list *current-thread*)
"The thread that was not interrupted.")
(defmacro with-interruptions-lock ((thread) &body body)
- `(without-interrupts
- (with-mutex ((thread-interruptions-lock ,thread))
- ,@body)))
+ `(call-with-system-mutex (lambda () ,@body) (thread-interruptions-lock ,thread)))
-;; Called from the signal handler.
+;; Called from the signal handler in C.
(defun run-interruption ()
(in-interruption ()
(loop
then do something that turns out to need those locks, you probably
won't like the effect."
#!-sb-thread (declare (ignore thread))
- ;; not quite perfect, because it does not take WITHOUT-INTERRUPTS
- ;; into account
#!-sb-thread
- (funcall function)
+ (with-interrupts (funcall function))
#!+sb-thread
(if (eq thread *current-thread*)
- (funcall function)
+ (with-interrupts (funcall function))
(let ((os-thread (thread-os-thread thread)))
(cond ((not os-thread)
(error 'interrupt-thread-error :thread thread))
projects / sbcl.git / blobdiff