Bug 696690 - Memory reporter for the startup cache. r=tglek.

modules/libjar/nsZipArchive.cpp

@@ -234,6 +234,11 @@ nsresult nsZipHandle::Init(nsZipArchive *zip, const char *entry,
   return NS_OK;
 }
 
+PRInt64 nsZipHandle::SizeOfMapping()
+{
+    return mLen;
+}
+
 nsZipHandle::~nsZipHandle()
 {
   if (mMap) {
@@ -775,6 +780,14 @@ MOZ_WIN_MEM_TRY_BEGIN
 MOZ_WIN_MEM_TRY_CATCH(return nsnull)
 }
 
+//---------------------------------------------
+// nsZipArchive::SizeOfMapping
+//---------------------------------------------
+PRInt64 nsZipArchive::SizeOfMapping()
+{
+    return mFd ? mFd->SizeOfMapping() : 0;
+}
+
 //------------------------------------------
 // nsZipArchive constructor and destructor
 //------------------------------------------

modules/libjar/nsZipArchive.h

@@ -221,6 +221,12 @@ public:
    */
   const PRUint8* GetData(nsZipItem* aItem);
 
+  /**
+   * Gets the amount of memory taken up by the archive's mapping.
+   * @return the size
+   */
+  PRInt64 SizeOfMapping();
+
 private:
   //--- private members ---
 
@@ -382,6 +388,8 @@ public:
   NS_METHOD_(nsrefcnt) AddRef(void);
   NS_METHOD_(nsrefcnt) Release(void);
 
+  PRInt64 SizeOfMapping();
+
 protected:
   const PRUint8 * mFileData; /* pointer to mmaped file */
   PRUint32        mLen;      /* length of file and memory mapped area */

startupcache/StartupCache.cpp

@@ -49,6 +49,7 @@
 #include "nsIClassInfo.h"
 #include "nsIFile.h"
 #include "nsILocalFile.h"
+#include "nsIMemoryReporter.h"
 #include "nsIObserver.h"
 #include "nsIObserverService.h"
 #include "nsIOutputStream.h"
@@ -81,6 +82,22 @@
 #define SC_WORDSIZE "8"
 #endif
 
+static PRInt64
+GetStartupCacheSize()
+{
+    mozilla::scache::StartupCache* sc = mozilla::scache::StartupCache::GetSingleton();
+    return sc ? sc->SizeOfMapping() : 0;
+}
+
+NS_MEMORY_REPORTER_IMPLEMENT(StartupCache,
+                             "explicit/startup-cache",
+                             KIND_NONHEAP,
+                             nsIMemoryReporter::UNITS_BYTES,
+                             GetStartupCacheSize,
+                             "Memory used to hold the startup cache.  This "
+                             "memory is backed by a file and is likely to be "
+                             "swapped out shortly after start-up.");
+
 namespace mozilla {
 namespace scache {
 
@@ -120,7 +137,8 @@ StartupCache* StartupCache::gStartupCache;
 bool StartupCache::gShutdownInitiated;
 
 StartupCache::StartupCache() 
-  : mArchive(NULL), mStartupWriteInitiated(false), mWriteThread(NULL) {}
+  : mArchive(NULL), mStartupWriteInitiated(false), mWriteThread(NULL),
+    mMemoryReporter(nsnull) { }
 
 StartupCache::~StartupCache() 
 {
@@ -134,6 +152,8 @@ StartupCache::~StartupCache()
   WaitOnWriteThread();
   WriteToDisk();
   gStartupCache = nsnull;
+  (void)::NS_UnregisterMemoryReporter(mMemoryReporter);
+  mMemoryReporter = nsnull;
 }
 
 nsresult
@@ -206,6 +226,10 @@ StartupCache::Init()
     NS_WARNING("Failed to load startupcache file correctly, removing!");
     InvalidateCache();
   }
+
+  mMemoryReporter = new NS_MEMORY_REPORTER_NAME(StartupCache);
+  (void)::NS_RegisterMemoryReporter(mMemoryReporter);
+
   return NS_OK;
 }
 
@@ -308,6 +332,12 @@ StartupCache::PutBuffer(const char* id, const char* inbuf, PRUint32 len)
   return ResetStartupWriteTimer();
 }
 
+PRInt64
+StartupCache::SizeOfMapping() 
+{
+    return mArchive ? mArchive->SizeOfMapping() : 0;
+}
+
 struct CacheWriteHolder
 {
   nsCOMPtr<nsIZipWriter> writer;

startupcache/StartupCache.h

@@ -95,6 +95,8 @@
  * provide some convenience in writing out data.
  */
 
+class nsIMemoryReporter;
+
 namespace mozilla {
 namespace scache {
 
@@ -148,6 +150,8 @@ public:
   static StartupCache* GetSingleton();
   static void DeleteSingleton();
 
+  PRInt64 SizeOfMapping();
+
 private:
   StartupCache();
   ~StartupCache();
@@ -178,6 +182,8 @@ private:
 #ifdef DEBUG
   nsTHashtable<nsISupportsHashKey> mWriteObjectMap;
 #endif
+
+  nsIMemoryReporter* mMemoryReporter;
 };
 
 // This debug outputstream attempts to detect if clients are writing multiple