Changeset 696 for soft/giet_vm/giet_kernel/ctx_handler.c

Timestamp:

Aug 7, 2015, 5:42:06 PM (9 years ago)

Author:

guerin

Message:

kernel: defer task exec to _ctx_switch()

File:

• soft/giet_vm/giet_kernel/ctx_handler.c (modified) (2 diffs)

soft/giet_vm/giet_kernel/ctx_handler.c

@@ -60 +60 @@
     // set NORUN_MASK_TASK bit
     _atomic_or( &psched->context[ltid][CTX_NORUN_ID], NORUN_MASK_TASK );
+}
+
+
+//////////////////
+static void _ctx_exec_task( unsigned int ltid )
+{
+    // get scheduler address
+    static_scheduler_t* psched = (static_scheduler_t*)_get_sched();
+
+    // TODO: reload .data segment
+
+    // find initial stack pointer
+    mapping_header_t * header  = (mapping_header_t *)SEG_BOOT_MAPPING_BASE;
+    mapping_task_t   * task    = _get_task_base(header);
+    mapping_vseg_t   * vseg    = _get_vseg_base(header);
+    unsigned int task_id       = psched->context[ltid][CTX_GTID_ID];
+    unsigned int vseg_id       = task[task_id].stack_vseg_id;
+    unsigned int sp_value      = vseg[vseg_id].vbase + vseg[vseg_id].length;
+
+    // reset task context: RA / SR / SP / EPC / NORUN
+    psched->context[ltid][CTX_RA_ID]    = (unsigned int)&_ctx_eret;
+    psched->context[ltid][CTX_SR_ID]    = GIET_SR_INIT_VALUE;
+    psched->context[ltid][CTX_SP_ID]    = sp_value;
+    psched->context[ltid][CTX_EPC_ID]   = psched->context[ltid][CTX_ENTRY_ID];
+    psched->context[ltid][CTX_NORUN_ID] = 0;
 }
 
@@ -128 +153 @@
             // acknowledge signal
             _atomic_and( &psched->context[next_task_id][CTX_SIG_ID], ~SIG_MASK_KILL );
-
-            // skip
-            continue;
+        }
+
+        // this task needs to be executed
+        if ( psched->context[next_task_id][CTX_SIG_ID] & SIG_MASK_EXEC )
+        {
+            _ctx_exec_task( next_task_id );
+
+            // acknowledge signal
+            _atomic_and( &psched->context[next_task_id][CTX_SIG_ID], ~SIG_MASK_EXEC );
         }