S390 kernel sigaction is the same as the Linux generic one.
Checked with a s390-linux-gnu and s390x-linux-gnu build.
* sysdeps/unix/sysv/linux/s390/kernel_sigaction.h: Use Linux generic
kernel_sigction definition.
The recent commit b4a5d26d88
"linux: Consolidate sigaction implementation" changed the definition
of struct sigaction for s390 (31bit). Unfortunately the order of the
fields were wrong.
This leads to blocking testcases e.g. nptl/tst-sem11.
A thread which blocks due to sem_wait() is cancelled via pthread_cancel()
and the signal-handler sigcancel_handler (see <glibc-src>/nptl/nptl-init.c
is called.
But it just returns as the siginfo_t argument is not setup by the kernel.
Then the main-thread is blocking due to pthread_join().
The flag SA_SIGINFO is set in sa_flags in struct sigaction and
is copied to the "kernel_sigaction.h" struct by the sigaction() call,
but due to the wrong ordering of the struct fields,
the kernel does not recognize it.
This patch consolidates all Linux sigaction implementations on the default
sysdeps/unix/sysv/linux/sigaction.c. The idea is remove redundant code
and simplify new ports addition by following the current generic
Linux User API (UAPI).
The UAPI for new ports defines a generic extensible sigaction struct as:
struct sigaction
{
__sighandler_t sa_handler;
unsigned long sa_flags;
#ifdef SA_RESTORER
void (*sa_restorer) (void);
#endif
sigset_t sa_mask;
};
Where SA_RESTORER is just placed for compatibility reasons (news ports
should not add it). A similar definition is used on generic
kernel_sigaction.h.
The user exported sigaction definition is not changed, so for most
architectures it requires an adjustment to kernel expected one for the
syscall.
The main changes are:
- All architectures now define and use a kernel_sigaction struct meant
for the syscall, even for the architectures where the user sigaction
has the same layout of the kernel expected one (s390-64 and ia64).
Although it requires more work for these architectures, it simplifies
the generic implementation. Also, sigaction is hardly a hotspot where
micro optimization would play an important role.
- The generic kernel_sigaction definition is now aligned with expected
UAPI one for newer ports, where SA_RESTORER and sa_restorer are not
expected to be defined. This means adding kernel_sigaction for
current architectures that does define it (m68k, nios2, powerpc, s390,
sh, sparc, and tile) and which rely on previous generic definition.
- Remove old MIPS usage of sa_restorer. This was removed since 2.6.27
(2957c9e61ee9c - "[MIPS] IRIX: Goodbye and thanks for all the fish").
- The remaining arch-specific sigaction.c are to handle ABI idiosyncrasies
(like SPARC kernel ABI for rt_sigaction that requires an additional
stub argument).
So for new ports the generic implementation should work if its uses
Linux UAPI. If SA_RESTORER is still required (due some architecture
limitation), it should define its own kernel_sigaction.h, define it and
include generic header (assuming it still uses the default generic kernel
layout).
Checked on x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabihf,
aarch64-linux-gnu, sparc64-linux-gnu, sparcv9-linux-gnu, powerpc-linux-gnu,
powerpc64-linux-gnu, ia64-linux-gnu and alpha-linux-gnu. I also checked the
build on all remaining affected ABIs.
* sysdeps/unix/sysv/linux/aarch64/sigaction.c: Use default Linux version
as base implementation.
* sysdeps/unix/sysv/linux/arm/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/i386/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/alpha/kernel_sigaction.h: Add include guards,
remove unrequired definitions and update comments.
* sysdeps/unix/sysv/linux/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/mips/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/ia64/kernel_sigaction.h: New file.
* sysdeps/unix/sysv/linux/m68k/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/nios2/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/kernel_sigaction: Likewise.
* sysdeps/unix/sysv/linux/s390/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/sh/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/tile/kernel_sigaction.h: Likewise.
* sysdeps/unix/sysv/linux/ia64/sigaction.c: Remove file.
* sysdeps/unix/sysv/linux/mips/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/sigaction.c: Add STUB, SET_SA_RESTORER,
and RESET_SA_RESTORER hooks.
