[COMMITTED] Clean up stack-coloring macros.
Commit Message
Adding -D switches in sysdeps/.../Makefile is (almost?) always the wrong
thing to do. It creates an implicit dependency not tracked by Make, and it
is usually not typo-proof and/or -Wundef-friendly. This change gets rid of
-Wundef warnings for these two macros.
Verified on x86_64-linux-gnu and i686-linux-gnu that no code changes
(except some assert line numbers).
* nptl/allocatestack.c: Include <stack-aliasing.h>.
* nptl/stack-aliasing.h: New file.
* sysdeps/i386/i686/stack-aliasing.h: New file.
* sysdeps/i386/i686/nptl/Makefile: File removed.
* sysdeps/x86_64/stack-aliasing.h: New file.
* sysdeps/x86_64/nptl/Makefile
(CFLAGS-pthread_create.c): Variable removed.
@@ -30,6 +30,7 @@
#include <list.h>
#include <lowlevellock.h>
#include <kernel-features.h>
+#include <stack-aliasing.h>
#ifndef NEED_SEPARATE_REGISTER_STACK
@@ -0,0 +1,29 @@
+/* Define macros for stack address aliasing issues for NPTL. Stub version.
+ Copyright (C) 2014 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* This is a number of bytes (less than a page) by which to "color" the
+ starting stack address of new threads. This number is multiplied by the
+ number of threads created so far and then truncated modulo page size,
+ to get a roughly even distribution of values for different threads. */
+#define COLORING_INCREMENT 0
+
+/* This is a number of bytes that is an alignment that should be avoided
+ when choosing the exact size of a new thread's stack. If the size
+ chosen is aligned to this, an extra page will be added to render the
+ size off-aligned. */
+#define MULTI_PAGE_ALIASING 0
@@ -1,31 +0,0 @@
-# Copyright (C) 2003-2014 Free Software Foundation, Inc.
-# This file is part of the GNU C Library.
-# Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
-
-# The GNU C Library is free software; you can redistribute it and/or
-# modify it under the terms of the GNU Lesser General Public
-# License as published by the Free Software Foundation; either
-# version 2.1 of the License, or (at your option) any later version.
-
-# The GNU C Library is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-# Lesser General Public License for more details.
-
-# You should have received a copy of the GNU Lesser General Public
-# License along with the GNU C Library; if not, see
-# <http://www.gnu.org/licenses/>.
-
-ifeq ($(subdir),nptl)
-# It turns out that stack coloring is in general not good on P4s. Some
-# applications will benefit. We will probably have a configuration option
-# at some point. Enabling coloring can be done with
-#
-# -DCOLORING_INCREMENT=128
-#
-# What is useful is to avoid the 64k aliasing problem which reliably
-# happens if all stacks use sizes which are a multiple of 64k. Tell
-# the stack allocator to disturb this by allocation one more page if
-# necessary.
-CFLAGS-pthread_create.c += -DMULTI_PAGE_ALIASING=65536
-endif
@@ -0,0 +1,28 @@
+/* Define macros for stack address aliasing issues for NPTL. i686 version.
+ Copyright (C) 2014 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* It turns out that stack coloring is in general not good on P4s. Some
+ applications will benefit. We will probably have a configuration option
+ at some point. To enable coloring, set this to 128. */
+#define COLORING_INCREMENT 0
+
+/* What is useful is to avoid the 64k aliasing problem which reliably
+ happens if all stacks use sizes which are a multiple of 64k. Tell
+ the stack allocator to disturb this by allocation one more page if
+ necessary. */
+#define MULTI_PAGE_ALIASING 65536
@@ -18,10 +18,3 @@
ifeq ($(subdir),csu)
gen-as-const-headers += tcb-offsets.sym
endif
-
-ifeq ($(subdir),nptl)
-# P4s have problems with 4M aliasing. We disturb the allocation of stacks
-# just enough so the subsequent allocations do not use stack address
-# (mod 4M) == 0.
-CFLAGS-pthread_create.c += -DMULTI_PAGE_ALIASING=65536
-endif
@@ -0,0 +1 @@
+#include <sysdeps/i386/i686/stack-aliasing.h>