Older ARC700 cores (ARC750 specifically) lack instructions to implement
atomic r-w-w. This is problematic for userspace libraries such as NPTL
which need atomic primitives. So enable them by providing kernel assist.
This is costly but really the only sane soluton (othern than tight
spinning using the otherwise availiable atomic exchange EX instruciton).
Good thing is there are only a few of these cores running Linux out in
the wild.
This only works on UP systems.
Reviewed-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The newer renameat2 syscall provides all the functionality provided by
the renameat syscall and adds flags, so future architectures won't need
to include renameat.
Therefore drop the renameat syscall from the generic syscall list unless
__ARCH_WANT_RENAMEAT is defined by the architecture's unistd.h prior to
including asm-generic/unistd.h, and adjust all architectures using the
generic syscall list to define it so that no in-tree architectures are
affected.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: linux-c6x-dev@linux-c6x.org
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-hexagon@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: nios2-dev@lists.rocketboards.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: uclinux-h8-devel@lists.sourceforge.jp
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Commit 97bc386fc1 "ARC: Add guard macro to uapi/asm/unistd.h"
inhibited multiple inclusion of ARCH unistd.h. This however hosed the system
since Generic syscall table generator relies on it being included twice,
and in lack-of an empty table was emitted by C preprocessor.
Fix that by allowing one exception to rule for the special case (just
like Xtensa)
Suggested-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Chen originally proposed this as "right thing to do" however I
actually ran into this when building perf tools. Some of the utils
include unistd.h as well as linux/unistd.h. Since -I includes kernel
headers too, we end up including the ARC unistd.h twice, leading to
redefinition nwarnings.
------------------>8-------------------
CC bench/sched-pipe.o
In file included from ~/kernel/arch/arc/include/uapi/asm/unistd.h:21:0,
from ~/kernel/include/uapi/linux/unistd.h:7,
from bench/sched-pipe.c:24:
~/kernel/include/uapi/asm-generic/unistd.h:889:0: error: "__NR_fcntl64"
redefined [-Werror]
#define __NR_fcntl64 __NR3264_fcntl
^
In file included from
~/gnu/arc-linux-uclibc/sys-include/sys/syscall.h:24:0,
from bench/../perf.h:112,
from bench/sched-pipe.c:13:
~/gnu/arc-linux-uclibc/include/bits/sysnum.h:761:0: note: this is the
location of the previous definition
------------------>8-------------------
Verified that make headers_install works fine with this.
Suggested-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: David Howells <dhowells@redhat.com>
1. ./genfilelist.pl arch/arc/include/asm/
2. Create arch/arc/include/uapi/asm/Kbuild as follows
+# UAPI Header export list
+include include/uapi/asm-generic/Kbuild.asm
3. ./disintegrate-one.pl arch/arc/include/{,uapi/}asm/<above-list>
4. Edit arch/arc/include/asm/Kbuild to remove ref to
asm-generic/Kbuild.asm
- To work around empty uapi/asm/setup.h added a placholder comment.
- Also a manual #ifdef __ASSEMBLY__ for a late ptrace change
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: David Howells <dhowells@redhat.com>
