Changeset 683 for trunk/kernel/kern/core.c

Timestamp:

Jan 13, 2021, 12:36:17 AM (3 years ago)

Author:

alain

Message:

All modifications required to support the <tcp_chat> application
including error recovery in case of packet loss.A

File:

• trunk/kernel/kern/core.c (modified) (7 diffs)

trunk/kernel/kern/core.c

@@ -3 +3 @@
  *
  * Author  Ghassan Almaless (2008,2009,2010,2011,2012)
- *         Alain Greiner (2016,2017,2018)
+ *         Alain Greiner    (2016,2017,2018,2019,2020)
  *
  * Copyright (c) UPMC Sorbonne Universites
@@ -47 +47 @@
         core->ticks_nr          = 0;
         core->usage             = 0;
-        core->spurious_irqs     = 0;
         core->fpu_owner         = NULL;
         core->rand_last         = hal_time_stamp() & 0xFFF;
@@ -55 +54 @@
 
     // initialise the alarms lock
-    busylock_init( &core->alarms_lock , LOCK_CORE_ALARMS );
+    remote_busylock_init( XPTR( local_cxy , &core->alarms_lock ) , LOCK_CORE_ALARMS );
 
     // initialise the alarms list 
@@ -61 +60 @@
 }
 
-///////////////////////////////////////
-void core_check_alarms( core_t * core )
+////////////////////////////////////////////////////////////////////////////////////
+// This static function checks the alarms registered in the core, and calls the
+// relevant alarm handler for all alarms whose time is elapded.
+// It does not take the lock protecting the alarm list, because it access only
+// the first alarm in the list, and all modifications in he list are done
+// the low level access functions called by the handler(s). 
+////////////////////////////////////////////////////////////////////////////////////
+static void core_check_alarms( core_t * core )
 {
     alarm_handler_t * handler;
@@ -72 +77 @@
     if( list_is_empty( root ) ) return;
 
-    // get pointer on first alarm when list non empty
-    alarm_t * alarm = LIST_FIRST( root , alarm_t , list );
-
-    // get first alarm date
-    cycle_t alarm_date = alarm->date; 
-
-    // get current date
-    cycle_t current_date = hal_get_cycles();
-
-    if( current_date >= alarm_date )
+    while( 1 )
     {
-        // get pointer on registered alarm handler
-        handler = (alarm_handler_t *)alarm->func_ptr;
-
-        // call alarm handler
-        handler( alarm->args_xp );
+        // get pointer on first alarm
+        alarm_t * alarm = LIST_FIRST( root , alarm_t , list );
+
+        // get first alarm date
+        cycle_t alarm_date = alarm->date; 
+
+        // get current date
+        cycle_t current_date = hal_get_cycles();
+
+        // call handler if delay elapsed, and retry
+        if( current_date >= alarm_date )
+        {
+            // get pointer on registered alarm handler
+            handler = (alarm_handler_t *)alarm->func_ptr;
+
+            // call alarm handler
+            handler( alarm->args_xp );
+        }
+        else   // exit loop when first alarm delay not elapsed
+        {
+            break;
+        }
     }
 }   // end core_check_alarms()
@@ -127 +140 @@
                     uint32_t * tm_us )
 {
-        *tm_s  = (core->ticks_nr*CONFIG_SCHED_TICK_MS_PERIOD)/1000;
-        *tm_us = (core->ticks_nr*CONFIG_SCHED_TICK_MS_PERIOD*1000)%1000000;
+    // get number of cycles
+    uint64_t cycles = core->cycles;
+
+    // get number of cycles per second
+    uint32_t cycles_per_second = LOCAL_CLUSTER->sys_clk;
+
+    *tm_s  = cycles / cycles_per_second;
+    *tm_us = (cycles * 1000000) % cycles_per_second;
 }
 
@@ -139 +158 @@
         ticks = core->ticks_nr++;
 
+    // handle alarms
+    core_check_alarms( core );
+
         // handle scheduler
         if( (ticks % CONFIG_SCHED_TICKS_PER_QUANTUM) == 0 ) sched_yield( "TICK");
-
-    // handle alarms
-    core_check_alarms( core );
 }