Made kern a switching header file directory.

SConstruct:
    Put the code to make a switching header directory into a function so they are easy to make.
src/arch/SConscript:
    Replace switching header code with the new function call.
src/kern/SConscript:
    Created a new switching header directory in kern, and moved the declaration of some source files here.

--HG--
rename : src/kern/kernel_stats.cc => src/kern/base_kernel_stats.cc
rename : src/kern/kernel_stats.hh => src/kern/base_kernel_stats.hh
extra : convert_revision : 98f5320a5ade567c3e4f67fef123dfb0c5122545

src/kern/SConscript

@@ -0,0 +1,69 @@
+# -*- mode:python -*-
+
+# Copyright (c) 2006 The Regents of The University of Michigan
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Steve Reinhardt
+
+import os.path, sys
+
+# Import build environment variable from SConstruct.
+Import('env')
+
+sources = Split('''
+	base_kernel_stats.cc
+	system_events.cc
+	linux/events.cc
+	linux/linux_syscalls.cc
+	linux/printk.cc
+	''')
+
+# Convert file names to SCons File objects.  This takes care of the
+# path relative to the top of the directory tree.
+sources = [File(s) for s in sources]
+
+#################################################################
+#
+# ISA "switch header" generation.
+#
+# Auto-generate arch headers that include the right ISA-specific
+# header based on the setting of THE_ISA preprocessor variable.
+#
+#################################################################
+
+# List of headers to generate
+kern_switch_hdrs = Split('''
+        kernel_stats.hh
+        ''')
+
+env.make_switching_dir('kern', kern_switch_hdrs, env)
+
+isa = env['TARGET_ISA'] # someday this may be a list of ISAs
+
+# Let the target architecture define what additional sources it needs
+sources += SConscript(os.path.join(isa, 'SConscript'), exports = 'env')
+
+Return('sources')