glibc/sysdeps/unix/sysv/linux/powerpc/not-errno.h
Tulio Magno Quites Machado Filho 4612268a0a powerpc: Fix syscalls during early process initialization [BZ #22685]
The tunables framework needs to execute syscall early in process
initialization, before the TCB is available for consumption.  This
behavior conflicts with powerpc{|64|64le}'s lock elision code, that
checks the TCB before trying to abort transactions immediately before
executing a syscall.

This patch adds a powerpc-specific implementation of __access_noerrno
that does not abort transactions before the executing syscall.

Tested on powerpc{|64|64le}.

	[BZ #22685]
	* sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION_IMPL): Renamed
	from ABORT_TRANSACTION.
	(ABORT_TRANSACTION): Redirect to ABORT_TRANSACTION_IMPL.
	* sysdeps/powerpc/powerpc64/sysdep.h (ABORT_TRANSACTION,
	ABORT_TRANSACTION_IMPL): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/not-errno.h: New file.  Reuse
	Linux code, but remove the code that aborts transactions.

Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
2018-01-19 09:50:09 -02:00

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C

/* Syscall wrapper that do not set errno. Linux powerpc version.
Copyright (C) 2018 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/>. */
/* __access_noerrno is used during process initialization in elf/dl-tunables.c
before the TCB is initialized, prohibiting the usage of
ABORT_TRANSACTION. */
#undef ABORT_TRANSACTION
#define ABORT_TRANSACTION
#include "sysdeps/unix/sysv/linux/not-errno.h"
/* Recover ABORT_TRANSACTION's previous value, in order to not affect
other syscalls. */
#undef ABORT_TRANSACTION
#define ABORT_TRANSACTION ABORT_TRANSACTION_IMPL