Changeset 683 for trunk/kernel/syscalls/sys_thread_sleep.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/syscalls/sys_thread_sleep.c (modified) (2 diffs)

trunk/kernel/syscalls/sys_thread_sleep.c

@@ -1 +1 @@
 /*
- * sys_thread_sleep.c - put the calling thread in sleep state
+ * sys_thread_sleep.c - block the calling thread on SLEEP, with or without alarm
  * 
- * Author    Alain Greiner (2016,2017)
+ * Author    Alain Greiner    (2016,2017,2018,2019,2020)
  *
  * Copyright (c) UPMC Sorbonne Universites
@@ -28 +28 @@
 #include <syscalls.h>
 
-//////////////////////
-int sys_thread_sleep( void )
+///////////////////////////////////////////////////////////////////////////////////////
+// This static function implements the alarm handler used to wake-up a thread
+// when the amarm rings after after a sleep( seconds ) syscall.
+///////////////////////////////////////////////////////////////////////////////////////
+// @ thread_xp  : extended pointer on blocked thread.
+///////////////////////////////////////////////////////////////////////////////////////
+static void __attribute__((noinline)) sleep_alarm_handler( xptr_t thread_xp )
 {
+    // stop the alarm
+    alarm_stop( thread_xp );
 
-    thread_t * this = CURRENT_THREAD;
+    // unblock the thread
+    thread_unblock( thread_xp , THREAD_BLOCKED_SLEEP );
+
+}  // end sleep_alarm_handler()
+
+////////////////////////////////////////
+int sys_thread_sleep( uint32_t seconds )
+{
+    cycle_t    ncycles;    // number of cycles to sleep
+
+    thread_t  * this      = CURRENT_THREAD;
+    xptr_t      thread_xp = XPTR( local_cxy , this );
+
+    cycle_t     tm_start = hal_get_cycles();
 
 #if DEBUG_SYS_THREAD_SLEEP
-uint64_t     tm_start;
-uint64_t     tm_end;
-tm_start = hal_get_cycles();
-if( DEBUG_SYS_THREAD_SLEEP < tm_start )
-printk("\n[DBG] %s : thread %x n process %x blocked / cycle %d\n",
-__FUNCTION__ , this->trdid, this->process->pid , (uint32_t)tm_start );
+if( DEBUG_SYS_THREAD_SLEEP < (uint32_t)tm_start )
+printk("\n[%s] thread[%x,%x] enter / cycle %d\n",
+__FUNCTION__, this->process->pid, this->trdid, (uint32_t)tm_start );
 #endif
 
-    thread_block( XPTR( local_cxy , this ) , THREAD_BLOCKED_GLOBAL );
-    sched_yield("blocked on sleep");
+    if( seconds == 0 )   // sleep without alarm
+    {
+ 
+#if DEBUG_SYS_THREAD_SLEEP
+if( DEBUG_SYS_THREAD_SLEEP < tm_start )
+printk("\n[%s] thread[%x,%x] blocks on <SLEEP> without alarm / cycle %d\n",
+__FUNCTION__ , this->process->pid, this->trdid, (uint32_t)tm_start );
+#endif
+        // threads blocks and deschedules
+        thread_block( thread_xp , THREAD_BLOCKED_SLEEP );
+        sched_yield("sleep without alarm");
+    }
+    else                // sleep with alarm
+    {
+        // translate seconds to ncycles
+        ncycles = seconds * LOCAL_CLUSTER->sys_clk;
+
+        // register & start the calling thread alarm
+        alarm_start( thread_xp,
+                     tm_start + ncycles,
+                     &sleep_alarm_handler,
+                     thread_xp );
+  
+#if DEBUG_SYS_THREAD_SLEEP
+if( DEBUG_SYS_THREAD_SLEEP < tm_start )
+printk("\n[DBG] %s : thread[%x,%x] blocks on <SLEEP> for %d seconds / cycle %d\n",
+__FUNCTION__ , this->process->pid,  this->trdid, seconds, (uint32_t)tm_start );
+#endif
+        // thread blocks & deschedules 
+        thread_block( thread_xp , THREAD_BLOCKED_SLEEP );
+        sched_yield("sleep with alarm");
+    }
 
 #if DEBUG_SYS_THREAD_SLEEP
-tm_end = hal_get_cycles();
 if( DEBUG_SYS_THREAD_SLEEP < tm_end )
-printk("\n[DBG] %s : thread %x in process %x resume / cycle %d\n",
-__FUNCTION__ , this->trdid, this->process->pid , (uint32_t)tm_end );
+printk("\n[%s] thread[%x,%x] resume / cycle %d\n",
+__FUNCTION__ , this->process->pid, this->trdid, (uint32_t)tm_end );
 #endif