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Diffstat (limited to 'third_party/lisp/sclf/mp/cmu.lisp')
| -rw-r--r-- | third_party/lisp/sclf/mp/cmu.lisp | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/third_party/lisp/sclf/mp/cmu.lisp b/third_party/lisp/sclf/mp/cmu.lisp new file mode 100644 index 000000000000..6617f6dadd5d --- /dev/null +++ b/third_party/lisp/sclf/mp/cmu.lisp @@ -0,0 +1,115 @@ +;;; +;;; Code freely lifted from various places with compatible license +;;; terms. Most of this code is copyright Gilbert Baumann +;;; <unk6@rz.uni-karlsruhe.de>. The bugs are copyright Walter +;;; C. Pelissero <walter@pelissero.de>. +;;; + +;;; This library is free software; you can redistribute it and/or +;;; modify it under the terms of the GNU Library General Public +;;; License as published by the Free Software Foundation; either +;;; version 2 of the License, or (at your option) any later version. +;;; +;;; This library is distributed in the hope that it will be useful, +;;; but WITHOUT ANY WARRANTY; without even the implied warranty of +;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +;;; Library General Public License for more details. +;;; +;;; You should have received a copy of the GNU Library General Public +;;; License along with this library; if not, write to the +;;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, +;;; Boston, MA 02111-1307 USA. + +(in-package :sclf) + +(defun make-lock (&optional name) + (mp:make-lock name)) + +(defun make-recursive-lock (&optional name) + (mp:make-lock name :kind :recursive)) + +(defmacro with-lock-held ((lock &key whostate (wait t) timeout) &body forms) + `(mp:with-lock-held (,lock ,(or whostate "Lock Wait") + :wait wait + ,@(when timeout (list :timeout timeout))) + ,@forms)) + +(defmacro with-recursive-lock-held ((lock &key wait timeout) &body forms) + `(mp:with-lock-held (,lock + ,@(when wait (list :wait wait)) + ,@(when timeout (list :timeout timeout))) + ,@forms)) + +(defstruct condition-variable + (lock (make-lock "condition variable")) + (value nil) + (process-queue nil)) + +(defun %release-lock (lock) ; copied from with-lock-held in multiproc.lisp + #+i486 (kernel:%instance-set-conditional + lock 2 mp:*current-process* nil) + #-i486 (when (eq (lock-process lock) mp:*current-process*) + (setf (lock-process lock) nil))) + +(defun condition-wait (cv lock &optional timeout) + (declare (ignore timeout)) ;For now + (loop + (let ((cv-lock (condition-variable-lock cv))) + (with-lock-held (cv-lock) + (when (condition-variable-value cv) + (setf (condition-variable-value cv) nil) + (return-from condition-wait t)) + (setf (condition-variable-process-queue cv) + (nconc (condition-variable-process-queue cv) + (list mp:*current-process*))) + (%release-lock lock)) + (mp:process-add-arrest-reason mp:*current-process* cv) + (let ((cv-val nil)) + (with-lock-held (cv-lock) + (setq cv-val (condition-variable-value cv)) + (when cv-val + (setf (condition-variable-value cv) nil))) + (when cv-val + (mp::lock-wait lock "waiting for condition variable lock") + (return-from condition-wait t)))))) + +(defun condition-notify (cv) + (with-lock-held ((condition-variable-lock cv)) + (let ((proc (pop (condition-variable-process-queue cv)))) + ;; The waiting process may have released the CV lock but not + ;; suspended itself yet + (when proc + (loop + for activep = (mp:process-active-p proc) + while activep + do (mp:process-yield)) + (setf (condition-variable-value cv) t) + (mp:process-revoke-arrest-reason proc cv)))) + ;; Give the other process a chance + (mp:process-yield)) + +(defun process-execute (process function) + (mp:process-preset process function) + ;; For some obscure reason process-preset doesn't make the process + ;; runnable. I'm sure it's me who didn't understand how + ;; multiprocessing works under CMUCL, despite the vast documentation + ;; available. + (mp:enable-process process) + (mp:process-add-run-reason process :enable)) + +(defun destroy-process (process) + ;; silnetly ignore a process that is trying to destroy itself + (unless (eq (mp:current-process) + process) + (mp:destroy-process process))) + +(defun restart-process (process) + (mp:restart-process process) + (mp:enable-process process) + (mp:process-add-run-reason process :enable)) + +(defun process-alive-p (process) + (mp:process-alive-p process)) + +(defun process-join (process) + (error "PROCESS-JOIN not support under CMUCL.")) |