Added kernel tracing for the swap support.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@27178 a95241bf-73f2-0310-859d-f6bbb57e9c96

build/config_headers/tracing_config.h

@@ -34,6 +34,7 @@
 #define RUNTIME_LOADER_TRACING					0
 #define SCHEDULER_TRACING						0
 #define SIGNAL_TRACING							0
+#define SWAP_TRACING							0
 #define SYSCALL_TRACING							0
 #define SYSCALL_TRACING_IGNORE_KTRACE_OUTPUT	1
 #define TCP_TRACING								0

src/system/kernel/vm/VMAnonymousCache.cpp

@@ -26,6 +26,7 @@
 #include <kernel_daemon.h>
 #include <slab/Slab.h>
 #include <syscalls.h>
+#include <tracing.h>
 #include <util/AutoLock.h>
 #include <util/DoublyLinkedList.h>
 #include <util/OpenHashTable.h>
@@ -147,6 +148,78 @@ static mutex sAvailSwapSpaceLock;
 static object_cache *sSwapBlockCache;
 
 
+#if SWAP_TRACING
+namespace SwapTracing {
+
+class SwapTraceEntry : public AbstractTraceEntry {
+public:
+	SwapTraceEntry(VMAnonymousCache* cache)
+		:
+		fCache(cache)
+	{
+	}
+
+protected:
+	VMAnonymousCache*	fCache;
+};
+
+
+class ReadPage : public SwapTraceEntry {
+public:
+	ReadPage(VMAnonymousCache* cache, page_num_t pageIndex,
+			swap_addr_t swapSlotIndex)
+		:
+		SwapTraceEntry(cache),
+		fPageIndex(pageIndex),
+		fSwapSlotIndex(swapSlotIndex)
+	{
+		Initialized();
+	}
+
+	virtual void AddDump(TraceOutput& out)
+	{
+		out.Print("swap read:  cache %p, page index: %lu <- swap slot: %lu",
+			fCache, fPageIndex, fSwapSlotIndex);
+	}
+
+private:
+	page_num_t		fPageIndex;
+	swap_addr_t		fSwapSlotIndex;
+};
+
+
+class WritePage : public SwapTraceEntry {
+public:
+	WritePage(VMAnonymousCache* cache, page_num_t pageIndex,
+			swap_addr_t swapSlotIndex)
+		:
+		SwapTraceEntry(cache),
+		fPageIndex(pageIndex),
+		fSwapSlotIndex(swapSlotIndex)
+	{
+		Initialized();
+	}
+
+	virtual void AddDump(TraceOutput& out)
+	{
+		out.Print("swap write: cache %p, page index: %lu -> swap slot: %lu",
+			fCache, fPageIndex, fSwapSlotIndex);
+	}
+
+private:
+	page_num_t		fPageIndex;
+	swap_addr_t		fSwapSlotIndex;
+};
+
+}	// namespace SwapTracing
+
+#	define T(x) new(std::nothrow) SwapTracing::x;
+#else
+#	define T(x) ;
+#endif
+
+
+
 static int
 dump_swap_info(int argc, char** argv)
 {
@@ -488,6 +561,9 @@ VMAnonymousCache::Read(off_t offset, const iovec *vecs, size_t count,
 				break;
 		}
 
+		T(ReadPage(this, pageIndex, startSlotIndex));
+			// TODO: Assumes that only one page is read.
+
 		swap_file *swapFile = find_swap_file(startSlotIndex);
 
 		off_t pos = (startSlotIndex - swapFile->first_slot) * B_PAGE_SIZE;
@@ -534,6 +610,9 @@ VMAnonymousCache::Write(off_t offset, const iovec *vecs, size_t count,
 		if (slotIndex == SWAP_SLOT_NONE)
 			panic("VMAnonymousCache::Write(): can't allocate swap space\n");
 
+		T(WritePage(this, pageIndex, slotIndex));
+			// TODO: Assumes that only one page is written.
+
 		swap_file *swapFile = find_swap_file(slotIndex);
 
 		off_t pos = (slotIndex - swapFile->first_slot) * B_PAGE_SIZE;
@@ -603,6 +682,8 @@ VMAnonymousCache::WriteAsync(off_t offset, const iovec* vecs, size_t count,
 
 	callback->SetTo(pageIndex, slotIndex, newSlot);
 
+	T(WritePage(this, pageIndex, slotIndex));
+
 	// write the page asynchrounously
 	swap_file* swapFile = find_swap_file(slotIndex);
 	off_t pos = (slotIndex - swapFile->first_slot) * B_PAGE_SIZE;