1 files changed, 244 insertions, 0 deletions

diff --git a/amd/clock.c b/amd/clock.c
new file mode 100644
index 000000000000..0caa7dff2c73
--- /dev/null
+++ b/amd/clock.c
@@ -0,0 +1,244 @@
+/*
+ * Copyright (c) 1997-2006 Erez Zadok
+ * Copyright (c) 1989 Jan-Simon Pendry
+ * Copyright (c) 1989 Imperial College of Science, Technology & Medicine
+ * Copyright (c) 1989 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Jan-Simon Pendry at Imperial College, London.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgment:
+ *      This product includes software developed by the University of
+ *      California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *
+ * File: am-utils/amd/clock.c
+ *
+ */
+
+/*
+ * Callouts.
+ *
+ * Modeled on kernel object of the same name.
+ * See usual references.
+ *
+ * Use of a heap-based mechanism was rejected:
+ * 1.  more complex implementation needed.
+ * 2.  not obvious that a list is too slow for Amd.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif /* HAVE_CONFIG_H */
+#include <am_defs.h>
+#include <amd.h>
+
+void reschedule_timeouts(time_t now, time_t then);
+
+typedef struct callout callout;
+struct callout {
+  callout *c_next;		/* List of callouts */
+  callout_fun *c_fn;		/* Function to call */
+  opaque_t c_arg;		/* Argument to pass to call */
+  time_t c_time;		/* Time of call */
+  int c_id;			/* Unique identifier */
+};
+
+static callout callouts;	/* List of pending callouts */
+static callout *free_callouts;	/* Cache of free callouts */
+static int nfree_callouts;	/* Number on free list */
+static int callout_id;		/* Next free callout identifier */
+
+time_t next_softclock;		/* Time of next call to softclock() */
+
+
+/*
+ * Number of callout slots we keep on the free list
+ */
+#define	CALLOUT_FREE_SLOP	10
+
+/*
+ * Global assumption: valid id's are non-zero.
+ */
+#define	CID_ALLOC()		(++callout_id)
+#define	CID_UNDEF		(0)
+
+
+static callout *
+alloc_callout(void)
+{
+  callout *cp = free_callouts;
+
+  if (cp) {
+    --nfree_callouts;
+    free_callouts = free_callouts->c_next;
+    return cp;
+  }
+  return ALLOC(struct callout);
+}
+
+
+static void
+free_callout(callout *cp)
+{
+  if (nfree_callouts > CALLOUT_FREE_SLOP) {
+    XFREE(cp);
+  } else {
+    cp->c_next = free_callouts;
+    free_callouts = cp;
+    nfree_callouts++;
+  }
+}
+
+
+/*
+ * Schedule a callout.
+ *
+ * (*fn)(fn_arg) will be called at clocktime(NULL) + secs
+ */
+int
+timeout(u_int secs, callout_fun *fn, opaque_t fn_arg)
+{
+  callout *cp, *cp2;
+  time_t t = clocktime(NULL) + secs;
+
+  /*
+   * Allocate and fill in a new callout structure
+   */
+  callout *cpnew = alloc_callout();
+  cpnew->c_arg = fn_arg;
+  cpnew->c_fn = fn;
+  cpnew->c_time = t;
+  cpnew->c_id = CID_ALLOC();
+
+  if (t < next_softclock)
+    next_softclock = t;
+
+  /*
+   * Find the correct place in the list
+   */
+  for (cp = &callouts; (cp2 = cp->c_next); cp = cp2)
+    if (cp2->c_time >= t)
+      break;
+
+  /*
+   * And link it in
+   */
+  cp->c_next = cpnew;
+  cpnew->c_next = cp2;
+
+  /*
+   * Return callout identifier
+   */
+  return cpnew->c_id;
+}
+
+
+/*
+ * De-schedule a callout
+ */
+void
+untimeout(int id)
+{
+  callout *cp, *cp2;
+  for (cp = &callouts; (cp2 = cp->c_next); cp = cp2) {
+    if (cp2->c_id == id) {
+      cp->c_next = cp2->c_next;
+      free_callout(cp2);
+      break;
+    }
+  }
+}
+
+
+/*
+ * Reschedule after clock changed
+ */
+void
+reschedule_timeouts(time_t now, time_t then)
+{
+  callout *cp;
+
+  for (cp = callouts.c_next; cp; cp = cp->c_next) {
+    if (cp->c_time >= now && cp->c_time <= then) {
+      plog(XLOG_WARNING, "job %d rescheduled to run immediately", cp->c_id);
+      dlog("rescheduling job %d back %ld seconds",
+	   cp->c_id, (long) (cp->c_time - now));
+      next_softclock = cp->c_time = now;
+    }
+  }
+}
+
+
+/*
+ * Clock handler
+ */
+int
+softclock(void)
+{
+  time_t now;
+  callout *cp;
+
+  do {
+    if (task_notify_todo)
+      do_task_notify();
+
+    now = clocktime(NULL);
+
+    /*
+     * While there are more callouts waiting...
+     */
+    while ((cp = callouts.c_next) && cp->c_time <= now) {
+      /*
+       * Extract first from list, save fn & fn_arg and
+       * unlink callout from list and free.
+       * Finally call function.
+       *
+       * The free is done first because
+       * it is quite common that the
+       * function will call timeout()
+       * and try to allocate a callout
+       */
+      callout_fun *fn = cp->c_fn;
+      opaque_t fn_arg = cp->c_arg;
+
+      callouts.c_next = cp->c_next;
+      free_callout(cp);
+      (*fn) (fn_arg);
+    }
+
+  } while (task_notify_todo);
+
+  /*
+   * Return number of seconds to next event,
+   * or 0 if there is no event.
+   */
+  if ((cp = callouts.c_next))
+    return cp->c_time - now;
+  return 0;
+}