systemc: Keep track of more cases when we should be ready after resume.

If a thread self suspends, it should be marked as ready after resuming.
If a process was already ready when suspended, it should also be
remarked as ready after resuming.

Special care has to be taken in pre-initialization situations so that
processes are put on the right lists, and whether a process is tracked
is already marked as ready.

Change-Id: I15da7d747db591785358d47781297468c5f9fd09
Reviewed-on: https://gem5-review.googlesource.com/c/12445
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

1 files changed, 11 insertions, 7 deletions

diff --git a/src/systemc/core/process.cc b/src/systemc/core/process.cc
index 830b8c729..1fd16e0d9 100644
--- a/src/systemc/core/process.cc
+++ b/src/systemc/core/process.cc
@@ -160,12 +160,16 @@ Process::suspend(bool inc_kids)
 
     if (!_suspended) {
         _suspended = true;
-        _suspendedReady = false;
-    }
-
-    if (procKind() != ::sc_core::SC_METHOD_PROC_ &&
-            scheduler.current() == this) {
-        scheduler.yield();
+        _suspendedReady = scheduler.suspend(this);
+
+        if (procKind() != ::sc_core::SC_METHOD_PROC_ &&
+                scheduler.current() == this) {
+            // This isn't in the spec, but Accellera says that a thread that
+            // self suspends should be marked ready immediately when it's
+            // resumed.
+            _suspendedReady = true;
+            scheduler.yield();
+        }
     }
 }
 
@@ -178,7 +182,7 @@ Process::resume(bool inc_kids)
     if (_suspended) {
         _suspended = false;
         if (_suspendedReady)
-            ready();
+            scheduler.resume(this);
         _suspendedReady = false;
     }
 }