Move the context_switch flag into the Capability

Fixes a long-standing bug that could in some cases cause sub-optimal
scheduling behaviour.

1 files changed, 7 insertions, 0 deletions

diff --git a/rts/Capability.h b/rts/Capability.h
index 94306eb6c0..70d9ee9e8d 100644
--- a/rts/Capability.h
+++ b/rts/Capability.h
@@ -66,6 +66,10 @@ struct Capability_ {
     // each GC.
     bdescr **mut_lists;
 
+    // Context switch flag. We used to have one global flag, now one 
+    // per capability. Locks required  : none (conflicts are harmless)
+    int context_switch;
+
 #if defined(THREADED_RTS)
     // Worker Tasks waiting in the wings.  Singly-linked.
     Task *spare_workers;
@@ -232,6 +236,9 @@ extern void grabCapability (Capability **pCap);
 
 #endif /* !THREADED_RTS */
 
+// cause all capabilities to context switch as soon as possible.
+void setContextSwitches(void);
+
 // Free a capability on exit
 void freeCapability (Capability *cap);