From 81fea743949e8fcd9f7738204f5853b2cd15c868 Mon Sep 17 00:00:00 2001
From: Michael Lotz <mmlr@mlotz.ch>
Date: Wed, 2 Nov 2011 16:09:49 +0000
Subject: [PATCH] bonefish+mmlr: Add
 MemoryManager::DebugObjectCacheForAddress() to retrieve the ObjectCache for a
 certain address from KDL.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@43117 a95241bf-73f2-0310-859d-f6bbb57e9c96
---
 src/system/kernel/slab/MemoryManager.cpp | 30 ++++++++++++++++++++++++
 src/system/kernel/slab/MemoryManager.h   |  2 ++
 2 files changed, 32 insertions(+)

diff --git a/src/system/kernel/slab/MemoryManager.cpp b/src/system/kernel/slab/MemoryManager.cpp
index bde45cedf5..3a6ac26f55 100644
--- a/src/system/kernel/slab/MemoryManager.cpp
+++ b/src/system/kernel/slab/MemoryManager.cpp
@@ -907,6 +907,36 @@ MemoryManager::AnalyzeAllocationCallers(AllocationTrackingCallback& callback)
 #endif	// SLAB_MEMORY_MANAGER_ALLOCATION_TRACKING
 
 
+/*static*/ ObjectCache*
+MemoryManager::DebugObjectCacheForAddress(void* address)
+{
+	// get the area
+	addr_t areaBase = _AreaBaseAddressForAddress((addr_t)address);
+	Area* area = sAreaTable.Lookup(areaBase);
+
+	if (area == NULL)
+		return NULL;
+
+	MetaChunk* metaChunk = &area->metaChunks[
+		((addr_t)address % SLAB_AREA_SIZE) / SLAB_CHUNK_SIZE_LARGE];
+
+	// get the chunk
+	if (metaChunk->chunkSize == 0)
+		return NULL;
+	if ((addr_t)address < metaChunk->chunkBase)
+		return NULL;
+
+	uint16 chunkIndex = _ChunkIndexForAddress(metaChunk, (addr_t)address);
+	Chunk* chunk = &metaChunk->chunks[chunkIndex];
+
+	addr_t reference = chunk->reference;
+	if ((reference & 1) == 0)
+		return (ObjectCache*)reference;
+
+	return NULL;
+}
+
+
 /*static*/ status_t
 MemoryManager::_AllocateChunks(size_t chunkSize, uint32 chunkCount,
 	uint32 flags, MetaChunk*& _metaChunk, Chunk*& _chunk)
diff --git a/src/system/kernel/slab/MemoryManager.h b/src/system/kernel/slab/MemoryManager.h
index 1e6cfbf781..0fe20cb18a 100644
--- a/src/system/kernel/slab/MemoryManager.h
+++ b/src/system/kernel/slab/MemoryManager.h
@@ -65,6 +65,8 @@ public:
 									AllocationTrackingCallback& callback);
 #endif
 
+	static	ObjectCache*		DebugObjectCacheForAddress(void* address);
+
 private:
 			struct Tracing;