This patch fixes 3dc214977 for sparc. Different than other architectures
SPARC kernel Kconfig does not define CONFIG_CLONE_BACKWARDS, however it
has the same ABI as if it did, implemented by sparc-specific code
(sparc_do_fork).
It also has a unique return value convention for clone:
Parent --> %o0 == child's pid, %o1 == 0
Child --> %o0 == parent's pid, %o1 == 1
Which required a special macro to correct issue the syscall
(INLINE_CLONE_SYSCALL).
Checked on sparc64-linux-gnu and sparcv9-linux-gnu.
* sysdeps/unix/sysv/linux/arch-fork.h [__ASSUME_CLONE_BACKWARDS]
(arch_fork): Issue INLINE_CLONE_SYSCALL if defined.
* sysdeps/unix/sysv/linux/sparc/kernel-features.h
(__ASSUME_CLONE_BACKWARDS): Define.
This patch refactors the ARCH_FORK macro and the required architecture
specific header to simplify the required architecture definitions
to provide the fork syscall semantic and proper document current
Linux clone ABI variant.
Instead of require the reimplementation of arch-fork.h header, this
patch changes the ARCH_FORK to an inline function with clone ABI
defined by kernel-features.h define. The generic kernel ABI meant
for newer ports is used as default and redefine if the architecture
requires.
Checked on x86_64-linux-gnu and i686-linux-gnu. Also with a build
for all the afected ABIs.
* sysdeps/nptl/fork.c (ARCH_FORK): Replace by auch_fork.
* sysdeps/unix/sysv/linux/alpha/arch-fork.h: Remove file.
* sysdeps/unix/sysv/linux/riscv/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/aarch64/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/arm/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/hppa/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/i386/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/ia64/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/m68k/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/microblaze/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/mips/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/nios2/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/s390/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/sh/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/tile/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/arch-fork.h: Likewise.
* sysdeps/unix/sysv/linux/arch-fork.h (arch_fork): New function.
* sysdeps/unix/sysv/linux/aarch64/kernel-features.h: New file.
* sysdeps/unix/sysv/linux/riscv/kernel-features.h: Likewise.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
(__ASSUME_CLONE_BACKWARDS): Define.
* sysdeps/unix/sysv/linux/createthread.c (ARCH_CLONE): Define to
__clone2 if __NR_clone2 is defined.
* sysdeps/unix/sysv/linux/hppa/kernel-features.h
(__ASSUME_CLONE_BACKWARDS): Likewise.
* sysdeps/unix/sysv/linux/i386/kernel-features.h
(__ASSUME_CLONE_BACKWARDS): Likewise.
* sysdeps/unix/sysv/linux/ia64/kernel-features.h
(__ASSUME_CLONE2): Likewise.
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
(__ASSUME_CLONE_BACKWARDS3): Likewise.
* sysdeps/unix/sysv/linux/kernel-features.h: Document possible clone
variants and the define architecture can use.
(__ASSUME_CLONE_DEFAULT): Define as default.
* sysdeps/unix/sysv/linux/mips/kernel-features.h
(__ASSUME_CLONE_BACKWARDS): Likewise.
* sysdeps/unix/sysv/linux/powerpc/kernel-features.h
(__ASSUME_CLONE_BACKWARDS): Likewise.
* sysdeps/unix/sysv/linux/s390/kernel-features.h
(__ASSUME_CLONE_BACKWARDS2): Likewise.
