score: New timer server implementation

Use mostly the standard watchdog operations.  Use a system event for
synchronization.  This implementation is simpler and offers better SMP
performance.

Close #2131.

5 files changed, 84 insertions, 108 deletions

diff --git a/cpukit/score/Makefile.am b/cpukit/score/Makefile.am
index af7da2ac53..3eb2caa902 100644
--- a/cpukit/score/Makefile.am
+++ b/cpukit/score/Makefile.am
@@ -324,7 +324,7 @@ libscore_a_SOURCES += src/coretod.c src/coretodset.c src/coretodget.c \
 
 ## WATCHDOG_C_FILES
 libscore_a_SOURCES += src/watchdog.c src/watchdogadjust.c \
-    src/watchdogadjusttochain.c src/watchdoginsert.c src/watchdogremove.c
+    src/watchdoginsert.c src/watchdogremove.c
 libscore_a_SOURCES += src/watchdogtickssinceboot.c
 
 ## USEREXT_C_FILES
diff --git a/cpukit/score/include/rtems/score/watchdogimpl.h b/cpukit/score/include/rtems/score/watchdogimpl.h
index dfe50e6d3a..6804bf24d4 100644
--- a/cpukit/score/include/rtems/score/watchdogimpl.h
+++ b/cpukit/score/include/rtems/score/watchdogimpl.h
@@ -165,6 +165,22 @@ void _Watchdog_Adjust_backward(
 );
 
 /**
+ * @brief Adjusts the watchdogs in backward direction in a locked context.
+ *
+ * The caller must be the owner of the watchdog lock and will be the owner
+ * after the call.
+ *
+ * @param[in] header The watchdog header.
+ * @param[in] units The units of ticks to adjust.
+ *
+ * @see _Watchdog_Adjust_forward().
+ */
+void _Watchdog_Adjust_backward_locked(
+  Watchdog_Header   *header,
+  Watchdog_Interval  units
+);
+
+/**
  *  @brief Adjusts the header watchdog chain in the forward direction for units
  *  ticks.
  *
@@ -179,24 +195,22 @@ void _Watchdog_Adjust_forward(
 );
 
 /**
- *  @brief Adjusts the @a header watchdog chain in the forward
- *  @a direction for @a units_arg ticks.
+ * @brief Adjusts the watchdogs in forward direction in a locked context.
  *
- *  This routine adjusts the @a header watchdog chain in the forward
- *  @a direction for @a units_arg ticks.
+ * The caller must be the owner of the watchdog lock and will be the owner
+ * after the call.  This function may release and acquire the watchdog lock
+ * internally.
  *
- *  @param[in] header is the watchdog chain to adjust
- *  @param[in] units_arg is the number of units to adjust @a header
- *  @param[in] to_fire is a pointer to an initialized Chain_Control to which
- *             all watchdog instances that are to be fired will be placed.
+ * @param[in] header The watchdog header.
+ * @param[in] units The units of ticks to adjust.
+ * @param[in] lock_context The lock context.
  *
- *  @note This always adjusts forward.
+ * @see _Watchdog_Adjust_forward().
  */
-void _Watchdog_Adjust_to_chain(
+void _Watchdog_Adjust_forward_locked(
   Watchdog_Header   *header,
-  Watchdog_Interval  units_arg,
-  Chain_Control     *to_fire
-
+  Watchdog_Interval  units,
+  ISR_lock_Context  *lock_context
 );
 
 /**
@@ -216,6 +230,25 @@ void _Watchdog_Insert (
 );
 
 /**
+ * @brief Inserts the watchdog in a locked context.
+ *
+ * The caller must be the owner of the watchdog lock and will be the owner
+ * after the call.  This function may release and acquire the watchdog lock
+ * internally.
+ *
+ * @param[in] header The watchdog header.
+ * @param[in] the_watchdog The watchdog.
+ * @param[in] lock_context The lock context.
+ *
+ * @see _Watchdog_Insert().
+ */
+void _Watchdog_Insert_locked(
+  Watchdog_Header  *header,
+  Watchdog_Control *the_watchdog,
+  ISR_lock_Context *lock_context
+);
+
+/**
  *  @brief This routine is invoked at appropriate intervals to update
  *  the @a header watchdog chain.
  *
diff --git a/cpukit/score/src/watchdogadjust.c b/cpukit/score/src/watchdogadjust.c
index 04fc1a55a7..32b5f7990e 100644
--- a/cpukit/score/src/watchdogadjust.c
+++ b/cpukit/score/src/watchdogadjust.c
@@ -19,26 +19,18 @@
 #endif
 
 #include <rtems/score/watchdogimpl.h>
-#include <rtems/score/chainimpl.h>
-#include <rtems/score/isrlevel.h>
 
-void _Watchdog_Adjust_backward(
+void _Watchdog_Adjust_backward_locked(
   Watchdog_Header   *header,
   Watchdog_Interval  units
 )
 {
-  ISR_lock_Context lock_context;
-
-  _Watchdog_Acquire( header, &lock_context );
-
   if ( !_Watchdog_Is_empty( header ) ) {
      _Watchdog_First( header )->delta_interval += units;
   }
-
-  _Watchdog_Release( header, &lock_context );
 }
 
-void _Watchdog_Adjust_forward(
+void _Watchdog_Adjust_backward(
   Watchdog_Header   *header,
   Watchdog_Interval  units
 )
@@ -46,7 +38,16 @@ void _Watchdog_Adjust_forward(
   ISR_lock_Context lock_context;
 
   _Watchdog_Acquire( header, &lock_context );
+  _Watchdog_Adjust_backward_locked( header, units );
+  _Watchdog_Release( header, &lock_context );
+}
 
+void _Watchdog_Adjust_forward_locked(
+  Watchdog_Header   *header,
+  Watchdog_Interval  units,
+  ISR_lock_Context  *lock_context
+)
+{
   while ( !_Watchdog_Is_empty( header ) && units > 0 ) {
     Watchdog_Control *first = _Watchdog_First( header );
 
@@ -57,13 +58,23 @@ void _Watchdog_Adjust_forward(
       units -= first->delta_interval;
       first->delta_interval = 1;
 
-      _Watchdog_Release( header, &lock_context );
+      _Watchdog_Release( header, lock_context );
 
       _Watchdog_Tickle( header );
 
-      _Watchdog_Acquire( header, &lock_context );
+      _Watchdog_Acquire( header, lock_context );
     }
   }
+}
 
+void _Watchdog_Adjust_forward(
+  Watchdog_Header   *header,
+  Watchdog_Interval  units
+)
+{
+  ISR_lock_Context lock_context;
+
+  _Watchdog_Acquire( header, &lock_context );
+  _Watchdog_Adjust_forward_locked( header, units, &lock_context );
   _Watchdog_Release( header, &lock_context );
 }
diff --git a/cpukit/score/src/watchdogadjusttochain.c b/cpukit/score/src/watchdogadjusttochain.c
deleted file mode 100644
index b3063e4109..0000000000
--- a/cpukit/score/src/watchdogadjusttochain.c
+++ /dev/null
@@ -1,75 +0,0 @@
-/**
- *  @file
- *
- *  @brief Watchdog Adjust to Chain
- *  @ingroup ScoreWatchdog
- */
-
-/*
- *  COPYRIGHT (c) 1989-2009.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.org/license/LICENSE.
- */
-
-#if HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <rtems/score/watchdogimpl.h>
-#include <rtems/score/isrlevel.h>
-
-void _Watchdog_Adjust_to_chain(
-  Watchdog_Header   *header,
-  Watchdog_Interval  units_arg,
-  Chain_Control     *to_fire
-
-)
-{
-  Watchdog_Interval  units = units_arg;
-  ISR_lock_Context   lock_context;
-  Watchdog_Control  *first;
-
-  _Watchdog_Acquire( header, &lock_context );
-
-  while ( 1 ) {
-    if ( _Watchdog_Is_empty( header ) ) {
-      break;
-    }
-    first = _Watchdog_First( header );
-
-    /*
-     *  If it is longer than "units" until the first element on the chain
-     *  fires, then bump it and quit.
-     */
-    if ( units < first->delta_interval ) {
-      first->delta_interval -= units;
-      break;
-    }
-
-    /*
-     *  The first set happens in less than units, so take all of them
-     *  off the chain and adjust units to reflect this.
-     */
-    units -= first->delta_interval;
-    first->delta_interval = 0;
-
-    while ( 1 ) {
-      _Chain_Extract_unprotected( &first->Node );
-      _Chain_Append_unprotected( to_fire, &first->Node );
-
-      _Watchdog_Flash( header, &lock_context );
-
-      if ( _Watchdog_Is_empty( header ) )
-        break;
-      first = _Watchdog_First( header );
-      if ( first->delta_interval != 0 )
-        break;
-    }
-  }
-
-  _Watchdog_Release( header, &lock_context );
-}
-
diff --git a/cpukit/score/src/watchdoginsert.c b/cpukit/score/src/watchdoginsert.c
index 6d2df8222f..6b81c7b872 100644
--- a/cpukit/score/src/watchdoginsert.c
+++ b/cpukit/score/src/watchdoginsert.c
@@ -47,15 +47,12 @@ static void _Watchdog_Insert_fixup(
   }
 }
 
-void _Watchdog_Insert(
+void _Watchdog_Insert_locked(
   Watchdog_Header  *header,
-  Watchdog_Control *the_watchdog
+  Watchdog_Control *the_watchdog,
+  ISR_lock_Context *lock_context
 )
 {
-  ISR_lock_Context lock_context;
-
-  _Watchdog_Acquire( header, &lock_context );
-
   if ( the_watchdog->state == WATCHDOG_INACTIVE ) {
     Watchdog_Iterator  iterator;
     Chain_Node        *current;
@@ -86,7 +83,7 @@ void _Watchdog_Insert(
       iterator.delta_interval = delta - delta_next;
       iterator.current = next;
 
-      _Watchdog_Flash( header, &lock_context );
+      _Watchdog_Flash( header, lock_context );
 
       if ( the_watchdog->state != WATCHDOG_BEING_INSERTED ) {
         goto abort_insert;
@@ -105,6 +102,16 @@ abort_insert:
 
     _Chain_Extract_unprotected( &iterator.Node );
   }
+}
 
+void _Watchdog_Insert(
+  Watchdog_Header  *header,
+  Watchdog_Control *the_watchdog
+)
+{
+  ISR_lock_Context lock_context;
+
+  _Watchdog_Acquire( header, &lock_context );
+  _Watchdog_Insert_locked( header, the_watchdog, &lock_context );
   _Watchdog_Release( header, &lock_context );
 }