From 35ccb414a25a786ff8df0166421cfc08db4d0cff Mon Sep 17 00:00:00 2001
From: Richard Brooksby <rb@ravenbrook.com>
Date: Fri, 31 Jan 2014 22:42:02 +0000
Subject: [PATCH] Adding arena extension back to the arena allocation policy.

Copied from Perforce
 Change: 184280
 ServerID: perforce.ravenbrook.com
---
 mps/code/arena.c    | 20 +++++++++++---------
 mps/code/arenavm.c  | 22 +++++++++++++++++-----
 mps/code/mpm.h      |  1 +
 mps/code/mpmst.h    |  1 +
 mps/code/mpmtypes.h |  1 +
 5 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/mps/code/arena.c b/mps/code/arena.c
index d30ed3cc41a..ce51bcc7e1d 100644
--- a/mps/code/arena.c
+++ b/mps/code/arena.c
@@ -68,6 +68,7 @@ DEFINE_CLASS(AbstractArenaClass, class)
   class->reserved = NULL;
   class->spareCommitExceeded = ArenaNoSpareCommitExceeded;
   class->extend = ArenaNoExtend;
+  class->grow = ArenaNoGrow;
   class->alloc = NULL;
   class->free = NULL;
   class->chunkInit = NULL;
@@ -702,14 +703,6 @@ failMark:
  * can be maintained and adjusted.
  */
 
-static Res arenaExtend(Arena arena, SegPref pref, Size size)
-{
-  UNUSED(arena);
-  UNUSED(pref);
-  UNUSED(size);
-  return ResUNIMPL;
-}
-
 static Res arenaAllocPolicy(Tract *tractReturn, Arena arena, SegPref pref,
                             Size size, Pool pool)
 {
@@ -754,7 +747,7 @@ static Res arenaAllocPolicy(Tract *tractReturn, Arena arena, SegPref pref,
   
   /* Plan C: Extend the arena, then try A and B again. */
   if (moreZones != ZoneSetEMPTY) {
-    res = arenaExtend(arena, pref, size);
+    res = arena->class->grow(arena, pref, size);
     if (res != ResOK)
       return res;
     zones = pref->zones;
@@ -986,6 +979,15 @@ void ArenaNoSpareCommitExceeded(Arena arena)
 }
 
 
+Res ArenaNoGrow(Arena arena, SegPref pref, Size size)
+{
+  AVERT(Arena, arena);
+  AVERT(SegPref, pref);
+  UNUSED(size);
+  return ResRESOURCE;
+}
+
+
 Size ArenaCommitLimit(Arena arena)
 {
   AVERT(Arena, arena);
diff --git a/mps/code/arenavm.c b/mps/code/arenavm.c
index 7c532964d57..8bb9159c82c 100644
--- a/mps/code/arenavm.c
+++ b/mps/code/arenavm.c
@@ -1103,17 +1103,27 @@ static Bool pagesFindFreeWithSegPref(Index *baseReturn, VMChunk *chunkReturn,
   }
   return FALSE;
 }
+#endif
 
 
-/* vmArenaExtend -- Extend the arena by making a new chunk
+/* vmArenaGrow -- Extend the arena by making a new chunk
  *
  * The size arg specifies how much we wish to allocate after the extension.
  */
-static Res vmArenaExtend(VMArena vmArena, Size size)
+static Res vmArenaGrow(Arena arena, SegPref pref, Size size)
 {
   Chunk newChunk;
   Size chunkSize;
   Res res;
+  VMArena vmArena;
+  
+  AVERT(Arena, arena);
+  vmArena = Arena2VMArena(arena);
+  AVERT(VMArena, vmArena);
+  
+  /* TODO: Ensure that extended arena will be able to satisfy pref. */
+  AVERT(SegPref, pref);
+  UNUSED(pref);
 
   /* Choose chunk size. */
   /* .vmchunk.overhead: This code still lacks a proper estimate of */
@@ -1170,12 +1180,12 @@ static Res vmArenaExtend(VMArena vmArena, Size size)
         }
         res = VMChunkCreate(&newChunk, vmArena, chunkSize);
         if(res == ResOK)
-          goto vmArenaExtend_Done;
+          goto vmArenaGrow_Done;
       }
     }
   }
 
-vmArenaExtend_Done:
+vmArenaGrow_Done:
   EVENT2(vmArenaExtendDone, chunkSize, VMArenaReserved(VMArena2Arena(vmArena)));
   vmArena->extended(VMArena2Arena(vmArena),
 		    newChunk->base,
@@ -1185,6 +1195,7 @@ vmArenaExtend_Done:
 }
 
 
+#if 0
 /* VM*AllocPolicy -- allocation policy methods */
 
 
@@ -1197,7 +1208,7 @@ static Res VMAllocPolicy(Index *baseIndexReturn, VMChunk *chunkReturn,
   if (!pagesFindFreeWithSegPref(baseIndexReturn, chunkReturn,
                                 vmArena, pref, size, FALSE)) {
     /* try and extend, but don't worry if we can't */
-    (void)vmArenaExtend(vmArena, size);
+    (void)vmArenaGrow(vmArena, size);
 
     /* We may or may not have a new chunk at this point */
     /* we proceed to try the allocation again anyway. */
@@ -1789,6 +1800,7 @@ DEFINE_ARENA_CLASS(VMArenaClass, this)
   this->finish = VMArenaFinish;
   this->reserved = VMArenaReserved;
   this->spareCommitExceeded = VMArenaSpareCommitExceeded;
+  this->grow = vmArenaGrow;
   this->alloc = VMAlloc;
   this->free = VMFree;
   this->chunkInit = VMChunkInit;
diff --git a/mps/code/mpm.h b/mps/code/mpm.h
index f4f2c5cd5c6..bc7b353be57 100644
--- a/mps/code/mpm.h
+++ b/mps/code/mpm.h
@@ -592,6 +592,7 @@ extern Res ArenaSetCommitLimit(Arena arena, Size limit);
 extern Size ArenaSpareCommitLimit(Arena arena);
 extern void ArenaSetSpareCommitLimit(Arena arena, Size limit);
 extern void ArenaNoSpareCommitExceeded(Arena arena);
+extern Res ArenaNoGrow(Arena arena, SegPref pref, Size size);
 
 extern double ArenaMutatorAllocSize(Arena arena);
 extern Size ArenaAvail(Arena arena);
diff --git a/mps/code/mpmst.h b/mps/code/mpmst.h
index 9290d0f7308..641143ca561 100644
--- a/mps/code/mpmst.h
+++ b/mps/code/mpmst.h
@@ -542,6 +542,7 @@ typedef struct mps_arena_class_s {
   ArenaReservedMethod reserved;
   ArenaSpareCommitExceededMethod spareCommitExceeded;
   ArenaExtendMethod extend;
+  ArenaGrowMethod grow;
   ArenaAllocMethod alloc;
   ArenaFreeMethod free;
   ArenaChunkInitMethod chunkInit;
diff --git a/mps/code/mpmtypes.h b/mps/code/mpmtypes.h
index 67d0e2b3763..652b2744035 100644
--- a/mps/code/mpmtypes.h
+++ b/mps/code/mpmtypes.h
@@ -121,6 +121,7 @@ typedef void (*ArenaFinishMethod)(Arena arena);
 typedef Size (*ArenaReservedMethod)(Arena arena);
 typedef void (*ArenaSpareCommitExceededMethod)(Arena arena);
 typedef Res (*ArenaExtendMethod)(Arena arena, Addr base, Size size);
+typedef Res (*ArenaGrowMethod)(Arena arena, SegPref pref, Size size);
 typedef Res (*ArenaAllocMethod)(Addr *baseReturn, Tract *baseTractReturn,
                                 SegPref pref, Size size, Pool pool);
 typedef void (*ArenaFreeMethod)(Addr base, Size size, Pool pool);