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commit 93a6d0820430bfe3d09695a1376c07abf6d2214f
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Author: Roland McGrath <roland@hack.frob.com>
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Date:   Fri Jun 20 19:50:16 2014 -0700
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    Clean up stack-coloring macros.
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Conflicts:
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	sysdeps/x86_64/nptl/Makefile
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File change was applied to nptl/sysdeps/x86_64/Makefile instead.
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diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
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index 2c126fd4ae447b25..0fba6ce3474e8b35 100644
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--- a/nptl/allocatestack.c
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+++ b/nptl/allocatestack.c
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@@ -30,6 +30,7 @@
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 #include <list.h>
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 #include <lowlevellock.h>
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 #include <kernel-features.h>
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+#include <stack-aliasing.h>
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 #ifndef NEED_SEPARATE_REGISTER_STACK
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diff --git a/nptl/stack-aliasing.h b/nptl/stack-aliasing.h
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new file mode 100644
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index 0000000000000000..526b54e18f7e0a27
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--- /dev/null
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+++ b/nptl/stack-aliasing.h
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@@ -0,0 +1,29 @@
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+/* Define macros for stack address aliasing issues for NPTL.  Stub version.
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+   Copyright (C) 2014 Free Software Foundation, Inc.
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+   This file is part of the GNU C Library.
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+
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+   The GNU C Library is free software; you can redistribute it and/or
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+   modify it under the terms of the GNU Lesser General Public
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+   License as published by the Free Software Foundation; either
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+   version 2.1 of the License, or (at your option) any later version.
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+
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+   The GNU C Library is distributed in the hope that it will be useful,
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+   but WITHOUT ANY WARRANTY; without even the implied warranty of
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+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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+   Lesser General Public License for more details.
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+
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+   You should have received a copy of the GNU Lesser General Public
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+   License along with the GNU C Library; if not, see
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+   <http://www.gnu.org/licenses/>.  */
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+
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+/* This is a number of bytes (less than a page) by which to "color" the
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+   starting stack address of new threads.  This number is multiplied by the
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+   number of threads created so far and then truncated modulo page size,
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+   to get a roughly even distribution of values for different threads.  */
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+#define COLORING_INCREMENT      0
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+
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+/* This is a number of bytes that is an alignment that should be avoided
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+   when choosing the exact size of a new thread's stack.  If the size
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+   chosen is aligned to this, an extra page will be added to render the
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+   size off-aligned.  */
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+#define MULTI_PAGE_ALIASING     0
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diff --git a/nptl/sysdeps/x86_64/Makefile b/nptl/sysdeps/x86_64/Makefile
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index d34dea709b363d2a..e2c47764e6e38c36 100644
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--- a/nptl/sysdeps/x86_64/Makefile
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+++ b/nptl/sysdeps/x86_64/Makefile
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@@ -18,10 +18,3 @@
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 ifeq ($(subdir),csu)
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 gen-as-const-headers += tcb-offsets.sym
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 endif
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-
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-ifeq ($(subdir),nptl)
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-# P4s have problems with 4M aliasing.  We disturb the allocation of stacks
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-# just enough so the subsequent allocations do not use stack address
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-# (mod 4M) == 0.
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-CFLAGS-pthread_create.c += -DMULTI_PAGE_ALIASING=65536
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-endif
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diff --git a/sysdeps/i386/i686/stack-aliasing.h b/sysdeps/i386/i686/stack-aliasing.h
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new file mode 100644
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index 0000000000000000..1e35ceb2061d60f9
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--- /dev/null
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+++ b/sysdeps/i386/i686/stack-aliasing.h
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@@ -0,0 +1,28 @@
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+/* Define macros for stack address aliasing issues for NPTL.  i686 version.
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+   Copyright (C) 2014 Free Software Foundation, Inc.
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+   This file is part of the GNU C Library.
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+
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+   The GNU C Library is free software; you can redistribute it and/or
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+   modify it under the terms of the GNU Lesser General Public
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+   License as published by the Free Software Foundation; either
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+   version 2.1 of the License, or (at your option) any later version.
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+
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+   The GNU C Library is distributed in the hope that it will be useful,
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+   but WITHOUT ANY WARRANTY; without even the implied warranty of
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+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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+   Lesser General Public License for more details.
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+
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+   You should have received a copy of the GNU Lesser General Public
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+   License along with the GNU C Library; if not, see
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+   <http://www.gnu.org/licenses/>.  */
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+
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+/* It turns out that stack coloring is in general not good on P4s.  Some
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+   applications will benefit.  We will probably have a configuration option
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+   at some point.  To enable coloring, set this to 128.  */
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+#define COLORING_INCREMENT      0
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+
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+/* What is useful is to avoid the 64k aliasing problem which reliably
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+   happens if all stacks use sizes which are a multiple of 64k.  Tell
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+   the stack allocator to disturb this by allocation one more page if
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+   necessary.  */
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+#define MULTI_PAGE_ALIASING     65536
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diff --git a/sysdeps/x86_64/stack-aliasing.h b/sysdeps/x86_64/stack-aliasing.h
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new file mode 100644
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index 0000000000000000..2efdacb3b4c44c40
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--- /dev/null
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+++ b/sysdeps/x86_64/stack-aliasing.h
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@@ -0,0 +1 @@
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+#include <sysdeps/i386/i686/stack-aliasing.h>