Add kernel virtual address space usage debug information.

kernel/addralloc.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2014 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2013, 2014, 2022 Jonas 'Sortie' Termansen.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -29,6 +29,7 @@
 namespace Sortix {
 
 size_t aux_allocated = 0;
+size_t aux_leaked = 0;
 size_t heap_allocated = 0;
 kthread_mutex_t alloc_lock = KTHREAD_MUTEX_INITIALIZER;
 
@@ -69,6 +70,8 @@ void FreeKernelAddress(addralloc_t* alloc)
 	addr_t aux_reached = kmem_from + kmem_size - aux_allocated;
 	if ( alloc->from == aux_reached )
 		aux_allocated -= alloc->size;
+	else
+		aux_leaked += alloc->size;
 
 	alloc->from = 0;
 	alloc->size = 0;
@@ -98,6 +101,17 @@ void ShrinkHeap(size_t decrease)
 	heap_allocated -= decrease;
 }
 
+void KernelAddressStatistics(size_t* heap, size_t* aux, size_t* leaked,
+                             size_t* total)
+{
+	ScopedLock lock(&alloc_lock);
+	addr_t kmem_from;
+	Memory::GetKernelVirtualArea(&kmem_from, total);
+	*heap = heap_allocated;
+	*aux = aux_allocated - aux_leaked;
+	*leaked = aux_leaked;
+}
+
 // No need for locks in these three functions, since only the heap calls these
 // and it already uses an internal lock, and heap_allocated will not change
 // unless the heap calls ExpandHeap.

kernel/include/sortix/kernel/addralloc.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2013, 2022 Jonas 'Sortie' Termansen.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -39,6 +39,7 @@ void ShrinkHeap(size_t decrease);
 addr_t GetHeapLower();
 addr_t GetHeapUpper();
 size_t GetHeapSize();
+void KernelAddressStatistics(size_t* heap, size_t* aux, size_t* leaked, size_t* total);
 
 } // namespace Sortix
 

kernel/kernelinfo.cpp

@@ -53,6 +53,26 @@ ssize_t sys_kernelinfo(const char* user_req, char* user_resp, size_t resplen)
 	if ( !req )
 		return -1;
 	// DEBUG
+	if ( !strcmp(req, "virtual-usage") )
+	{
+		delete[] req;
+		size_t heap;
+		size_t aux;
+		size_t leaked;
+		size_t total;
+		KernelAddressStatistics(&heap, &aux, &leaked, &total);
+		char str[4 * (20 + 3 * sizeof(size_t) + 1 + 8)];
+		snprintf(str, sizeof(str),
+		         "%20zu B heap\n%20zu B aux\n%20zu B leaked\n%20zu B total",
+		         heap, aux, leaked, total);
+		size_t stringlen = strlen(str);
+		if ( resplen < stringlen + 1 )
+			return errno = ERANGE, (ssize_t) stringlen;
+		if ( !CopyToUser(user_resp, str, sizeof(char) * (stringlen + 1)) )
+			return -1;
+		return 0;
+	}
+	// DEBUG
 	if ( !strcmp(req, "tcp") )
 	{
 		delete[] req;