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| author | H.J. Lu <hjl.tools@gmail.com> | 2021-03-19 12:53:40 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2021-03-19 15:04:17 -0700 |
| commit | 3e2f285c5f12045e425060b6cbdf7a7cab540594 (patch) | |
| tree | d85f4e33fd6caa432c8e877555d0a573c1523db4 /nptl | |
| parent | 9cbe4ed14ec66415be34ad142abf4fa83aed3f58 (diff) | |
| download | glibc-3e2f285c5f12045e425060b6cbdf7a7cab540594.zip glibc-3e2f285c5f12045e425060b6cbdf7a7cab540594.tar.gz glibc-3e2f285c5f12045e425060b6cbdf7a7cab540594.tar.bz2 | |
nptl: Remove MULTI_PAGE_ALIASING [BZ #23554]
MULTI_PAGE_ALIASING was introduced to mitigate an aliasing issue on
Pentium 4. It is no longer needed for processors after Pentium 4.
Diffstat (limited to 'nptl')
| -rw-r--r-- | nptl/allocatestack.c | 10 | ||||
| -rw-r--r-- | nptl/stack-aliasing.h | 23 |
2 files changed, 0 insertions, 33 deletions
diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c index 149b999..00fddbd 100644 --- a/nptl/allocatestack.c +++ b/nptl/allocatestack.c @@ -31,7 +31,6 @@ #include <lowlevellock.h> #include <futex-internal.h> #include <kernel-features.h> -#include <stack-aliasing.h> #ifndef NEED_SEPARATE_REGISTER_STACK @@ -547,15 +546,6 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp, pd = get_cached_stack (&size, &mem); if (pd == NULL) { - /* To avoid aliasing effects on a larger scale than pages we - adjust the allocated stack size if necessary. This way - allocations directly following each other will not have - aliasing problems. */ -#if MULTI_PAGE_ALIASING != 0 - if ((size % MULTI_PAGE_ALIASING) == 0) - size += pagesize_m1 + 1; -#endif - /* If a guard page is required, avoid committing memory by first allocate with PROT_NONE and then reserve with required permission excluding the guard page. */ diff --git a/nptl/stack-aliasing.h b/nptl/stack-aliasing.h deleted file mode 100644 index bfdde53..0000000 --- a/nptl/stack-aliasing.h +++ /dev/null @@ -1,23 +0,0 @@ -/* Define macros for stack address aliasing issues for NPTL. Stub version. - Copyright (C) 2014-2021 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 - <https://www.gnu.org/licenses/>. */ - -/* 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 |