* Added kernel tracing for the page daemon and the page writer.

* Added some commented out debug output in vm.cpp. 


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@27971 a95241bf-73f2-0310-859d-f6bbb57e9c96

build/config_headers/tracing_config.h

@@ -28,6 +28,8 @@
 #define KERNEL_HEAP_TRACING						0
 #define KTRACE_PRINTF_STACK_TRACE				0	/* stack trace depth */
 #define PAGE_ALLOCATION_TRACING					0
+#define PAGE_DAEMON_TRACING						0
+#define PAGE_WRITER_TRACING						0
 #define PARANOIA_TRACING						0
 #define PARANOIA_TRACING_STACK_TRACE			0	/* stack trace depth */
 #define OBJECT_CACHE_TRACING					0

src/system/kernel/vm/vm.cpp

@@ -1529,6 +1529,9 @@ map_backing_store(vm_address_space *addressSpace, vm_cache *cache,
 	// grab a ref to the address space (the area holds this)
 	atomic_add(&addressSpace->ref_count, 1);
 
+//	ktrace_printf("map_backing_store: cache: %p (source: %p), \"%s\" -> %p",
+//		cache, sourceCache, areaName, area);
+
 	*_area = area;
 	return B_OK;
 
@@ -4717,6 +4720,10 @@ vm_soft_fault(vm_address_space *addressSpace, addr_t originalAddress,
 		return B_BAD_ADDRESS;
 	}
 
+//	ktrace_printf("page fault: %s %#lx, %s, area: %p",
+//		isWrite ? "write" : "read", originalAddress, isUser ? "user" : "kernel",
+//		area);
+
 	// check permissions
 	uint32 protection = get_area_page_protection(area, address);
 	if (isUser && (protection & B_USER_PROTECTION) == 0) {

src/system/kernel/vm/vm_daemons.cpp

@@ -12,6 +12,7 @@
 
 #include <OS.h>
 
+#include <tracing.h>
 #include <vm.h>
 #include <vm_priv.h>
 #include <vm_cache.h>
@@ -109,6 +110,84 @@ PageCacheLocker::Unlock()
 //	#pragma mark -
 
 
+#if PAGE_DAEMON_TRACING
+
+namespace PageDaemonTracing {
+
+class ActivatePage : public AbstractTraceEntry {
+	public:
+		ActivatePage(vm_page* page)
+			:
+			fCache(page->cache),
+			fPage(page)
+		{
+			Initialized();
+		}
+
+		virtual void AddDump(TraceOutput& out)
+		{
+			out.Print("page activated:   %p, cache: %p", fPage, fCache);
+		}
+
+	private:
+		VMCache*	fCache;
+		vm_page*	fPage;
+};
+
+
+class DeactivatePage : public AbstractTraceEntry {
+	public:
+		DeactivatePage(vm_page* page)
+			:
+			fCache(page->cache),
+			fPage(page)
+		{
+			Initialized();
+		}
+
+		virtual void AddDump(TraceOutput& out)
+		{
+			out.Print("page deactivated: %p, cache: %p", fPage, fCache);
+		}
+
+	private:
+		VMCache*	fCache;
+		vm_page*	fPage;
+};
+
+
+class FreedPageSwap : public AbstractTraceEntry {
+	public:
+		FreedPageSwap(vm_page* page)
+			:
+			fCache(page->cache),
+			fPage(page)
+		{
+			Initialized();
+		}
+
+		virtual void AddDump(TraceOutput& out)
+		{
+			out.Print("page swap freed:  %p, cache: %p", fPage, fCache);
+		}
+
+	private:
+		VMCache*	fCache;
+		vm_page*	fPage;
+};
+
+}	// namespace PageDaemonTracing
+
+#	define T(x)	new(std::nothrow) PageDaemonTracing::x
+
+#else
+#	define T(x)
+#endif	// PAGE_DAEMON_TRACING
+
+
+//	#pragma mark -
+
+
 #ifdef TRACK_PAGE_USAGE_STATS
 
 static void
@@ -205,6 +284,7 @@ check_page_activation(int32 index)
 				vm_page_set_state(page, PAGE_STATE_ACTIVE);
 			page->usage_count = 1;
 			TRACE(("page %p -> move to active\n", page));
+			T(ActivatePage(page));
 		} else if (page->usage_count < 127)
 			page->usage_count++;
 
@@ -237,6 +317,7 @@ check_page_activation(int32 index)
 		else
 			vm_page_set_state(page, PAGE_STATE_INACTIVE);
 		TRACE(("page %p -> move to inactive\n", page));
+		T(DeactivatePage(page));
 	}
 
 	return true;
@@ -260,6 +341,7 @@ free_page_swap_space(int32 index)
 			// We need to mark the page modified, since otherwise it could be
 			// stolen and we'd lose its data.
 			vm_page_set_state(page, PAGE_STATE_MODIFIED);
+			T(FreedPageSwap(page));
 			return true;
 		}
 	}
@@ -299,7 +381,7 @@ page_daemon(void* /*unused*/)
 			* pagesLeft / sLowPagesCount;
 		uint32 leftToFree = sLowPagesCount - pagesLeft;
 		TRACE(("wait interval %Ld, scan pages %lu, free %lu, "
-			"target %lu\n",	scanWaitInterval, scanPagesCount, 
+			"target %lu\n",	scanWaitInterval, scanPagesCount,
 			pagesLeft, leftToFree));
 
 		for (uint32 i = 0; i < scanPagesCount && leftToFree > 0; i++) {

src/system/kernel/vm/vm_page.cpp

@@ -230,6 +230,39 @@ class StolenPage : public AbstractTraceEntry {
 #endif	// PAGE_ALLOCATION_TRACING
 
 
+#if PAGE_WRITER_TRACING
+
+namespace PageWriterTracing {
+
+class WritePage : public AbstractTraceEntry {
+	public:
+		WritePage(vm_page* page)
+			:
+			fCache(page->cache),
+			fPage(page)
+		{
+			Initialized();
+		}
+
+		virtual void AddDump(TraceOutput& out)
+		{
+			out.Print("page write: %p, cache: %p", fPage, fCache);
+		}
+
+	private:
+		VMCache*	fCache;
+		vm_page*	fPage;
+};
+
+}	// namespace PageWriterTracing
+
+#	define TPW(x)	new(std::nothrow) PageWriterTracing::x
+
+#else
+#	define TPW(x)
+#endif	// PAGE_WRITER_TRACING
+
+
 /*!	Dequeues a page from the head of the given queue */
 static vm_page *
 dequeue_page(page_queue *queue)
@@ -1222,6 +1255,8 @@ page_writer(void* /*unused*/)
 			locker.Unlock();
 
 			//dprintf("write page %p, cache %p (%ld)\n", page, page->cache, page->cache->ref_count);
+			TPW(WritePage(page));
+
 			vm_clear_map_flags(page, PAGE_MODIFIED);
 			cache->AcquireRefLocked();
 			numPages++;