From aeb4d2e9815d459e2640a31f5abb8ef803830107 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Tue, 30 Aug 2022 10:33:15 -0300 Subject: [PATCH] m68k: Enforce 4-byte alignment on internal locks (BZ #29537) A new internal definition, __LIBC_LOCK_ALIGNMENT, is used to force the 4-byte alignment only for m68k, other architecture keep the natural alignment of the type used internally (and hppa does not require 16-byte alignment for kernel-assisted CAS). Reviewed-by: Florian Weimer --- sysdeps/generic/libc-lock-arch.h | 25 +++++++++++++++++++ sysdeps/nptl/libc-lock.h | 8 +++++- sysdeps/nptl/libc-lockP.h | 3 ++- sysdeps/unix/sysv/linux/m68k/libc-lock-arch.h | 25 +++++++++++++++++++ 4 files changed, 59 insertions(+), 2 deletions(-) create mode 100644 sysdeps/generic/libc-lock-arch.h create mode 100644 sysdeps/unix/sysv/linux/m68k/libc-lock-arch.h diff --git a/sysdeps/generic/libc-lock-arch.h b/sysdeps/generic/libc-lock-arch.h new file mode 100644 index 0000000000..4713b30a8a --- /dev/null +++ b/sysdeps/generic/libc-lock-arch.h @@ -0,0 +1,25 @@ +/* Private libc-internal arch-specific definitions. Generic version. + Copyright (C) 2022 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; see the file COPYING.LIB. If + not, see . */ + +#ifndef _LIBC_LOCK_ARCH_H +#define _LIBC_LOCK_ARCH_H + +/* The default definition uses the natural alignment from the lock type. */ +#define __LIBC_LOCK_ALIGNMENT + +#endif diff --git a/sysdeps/nptl/libc-lock.h b/sysdeps/nptl/libc-lock.h index 5af476c48b..63b3f3d75c 100644 --- a/sysdeps/nptl/libc-lock.h +++ b/sysdeps/nptl/libc-lock.h @@ -22,6 +22,7 @@ #include #define __need_NULL #include +#include /* Mutex type. */ @@ -29,7 +30,12 @@ # if (!IS_IN (libc) && !IS_IN (libpthread)) || !defined _LIBC typedef struct { pthread_mutex_t mutex; } __libc_lock_recursive_t; # else -typedef struct { int lock; int cnt; void *owner; } __libc_lock_recursive_t; +typedef struct +{ + int lock __LIBC_LOCK_ALIGNMENT; + int cnt; + void *owner; +} __libc_lock_recursive_t; # endif #else typedef struct __libc_lock_recursive_opaque__ __libc_lock_recursive_t; diff --git a/sysdeps/nptl/libc-lockP.h b/sysdeps/nptl/libc-lockP.h index d3a6837fd2..425f514c5c 100644 --- a/sysdeps/nptl/libc-lockP.h +++ b/sysdeps/nptl/libc-lockP.h @@ -32,9 +32,10 @@ ld.so might be used on old kernels with a different libc.so. */ #include #include +#include /* Mutex type. */ -typedef int __libc_lock_t; +typedef int __libc_lock_t __LIBC_LOCK_ALIGNMENT; typedef struct { pthread_mutex_t mutex; } __rtld_lock_recursive_t; typedef pthread_rwlock_t __libc_rwlock_t; diff --git a/sysdeps/unix/sysv/linux/m68k/libc-lock-arch.h b/sysdeps/unix/sysv/linux/m68k/libc-lock-arch.h new file mode 100644 index 0000000000..1844bbaf6f --- /dev/null +++ b/sysdeps/unix/sysv/linux/m68k/libc-lock-arch.h @@ -0,0 +1,25 @@ +/* Private libc-internal arch-specific definitions. m68k version. + Copyright (C) 2022 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; see the file COPYING.LIB. If + not, see . */ + +#ifndef _LIBC_LOCK_ARCH_H +#define _LIBC_LOCK_ARCH_H + +/* Linux enforces 4-bytes alignment on futex inputs. */ +#define __LIBC_LOCK_ALIGNMENT __attribute__ ((__aligned__ (4))) + +#endif