From 5178da7f966c810c3d64fee02c1161406f9ac1d2 Mon Sep 17 00:00:00 2001
From: Simon Marlow <marlowsd@gmail.com>
Date: Thu, 31 Dec 2009 16:02:23 +0000
Subject: [PATCH] take newCAF() out from sm_mutex; use the capability-local
 mut list instead

---
 compiler/codeGen/CgClosure.lhs |    5 ++++-
 includes/rts/storage/GC.h      |    4 ++--
 rts/sm/Storage.c               |   34 +++++++++++++++++-----------------
 3 files changed, 23 insertions(+), 20 deletions(-)

diff --git a/compiler/codeGen/CgClosure.lhs b/compiler/codeGen/CgClosure.lhs
index 104af14..f0fe3d1 100644
--- a/compiler/codeGen/CgClosure.lhs
+++ b/compiler/codeGen/CgClosure.lhs
@@ -560,7 +560,10 @@ link_caf cl_info _is_upd = do
 	-- so that the garbage collector can find them
 	-- This must be done *before* the info table pointer is overwritten, 
 	-- because the old info table ptr is needed for reversion
-  ; emitRtsCallWithVols rtsPackageId (fsLit "newCAF") [CmmHinted (CmmReg nodeReg) AddrHint] [node] False
+  ; emitRtsCallWithVols rtsPackageId (fsLit "newCAF")
+      [ CmmHinted (CmmReg (CmmGlobal BaseReg)) AddrHint,
+        CmmHinted (CmmReg nodeReg) AddrHint ]
+      [node] False
 	-- node is live, so save it.
 
 	-- Overwrite the closure with a (static) indirection 
diff --git a/includes/rts/storage/GC.h b/includes/rts/storage/GC.h
index 2a21c66..9749c02 100644
--- a/includes/rts/storage/GC.h
+++ b/includes/rts/storage/GC.h
@@ -167,8 +167,8 @@ void performMajorGC(void);
    The CAF table - used to let us revert CAFs in GHCi
    -------------------------------------------------------------------------- */
 
-void newCAF     (StgClosure*);
-void newDynCAF  (StgClosure *);
+void newCAF     (StgRegTable *reg, StgClosure *);
+void newDynCAF  (StgRegTable *reg, StgClosure *);
 void revertCAFs (void);
 
 /* -----------------------------------------------------------------------------
diff --git a/rts/sm/Storage.c b/rts/sm/Storage.c
index 781234a..1f875a9 100644
--- a/rts/sm/Storage.c
+++ b/rts/sm/Storage.c
@@ -94,7 +94,7 @@ initGeneration (generation *gen, int g)
 void
 initStorage( void )
 {
-  nat g;
+    nat g, n;
 
   if (generations != NULL) {
       // multi-init protection
@@ -192,6 +192,13 @@ initStorage( void )
 
   N = 0;
 
+  // allocate a block for each mut list
+  for (n = 0; n < n_capabilities; n++) {
+      for (g = 1; g < RtsFlags.GcFlags.generations; g++) {
+          capabilities[n].mut_lists[g] = allocBlock();
+      }
+  }
+
   initGcThreads();
 
   IF_DEBUG(gc, statDescribeGens());
@@ -234,8 +241,8 @@ freeStorage (void)
 
    newCaf() does the following:
        
-      - it puts the CAF on the oldest generation's mut-once list.
-        This is so that we can treat the CAF as a root when collecting
+      - it puts the CAF on the oldest generation's mutable list.
+        This is so that we treat the CAF as a root when collecting
 	younger generations.
 
    For GHCI, we have additional requirements when dealing with CAFs:
@@ -259,10 +266,8 @@ freeStorage (void)
    -------------------------------------------------------------------------- */
 
 void
-newCAF(StgClosure* caf)
+newCAF(StgRegTable *reg, StgClosure* caf)
 {
-  ACQUIRE_SM_LOCK;
-
 #ifdef DYNAMIC
   if(keepCAFs)
   {
@@ -277,24 +282,19 @@ newCAF(StgClosure* caf)
     // do another hack here and do an address range test on caf to figure
     // out whether it is from a dynamic library.
     ((StgIndStatic *)caf)->saved_info  = (StgInfoTable *)caf->header.info;
+
+    ACQUIRE_SM_LOCK; // caf_list is global, locked by sm_mutex
     ((StgIndStatic *)caf)->static_link = caf_list;
     caf_list = caf;
+    RELEASE_SM_LOCK;
   }
   else
 #endif
   {
-    /* Put this CAF on the mutable list for the old generation.
-    * This is a HACK - the IND_STATIC closure doesn't really have
-    * a mut_link field, but we pretend it has - in fact we re-use
-    * the STATIC_LINK field for the time being, because when we
-    * come to do a major GC we won't need the mut_link field
-    * any more and can use it as a STATIC_LINK.
-    */
+    // Put this CAF on the mutable list for the old generation.
     ((StgIndStatic *)caf)->saved_info = NULL;
-    recordMutableGen(caf, oldest_gen->no);
+    recordMutableCap(caf, regTableToCapability(reg), oldest_gen->no);
   }
-  
-  RELEASE_SM_LOCK;
 }
 
 // An alternate version of newCaf which is used for dynamically loaded
@@ -307,7 +307,7 @@ newCAF(StgClosure* caf)
 // The linker hackily arranges that references to newCaf from dynamic
 // code end up pointing to newDynCAF.
 void
-newDynCAF(StgClosure *caf)
+newDynCAF (StgRegTable *reg STG_UNUSED, StgClosure *caf)
 {
     ACQUIRE_SM_LOCK;
 
-- 
1.7.10.4