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glibc/sysdeps/unix/sysv/linux/microblaze/pselect32.c

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misc: Set generic pselect as ENOSYS The generic pselect implementation has the very specific race condition that motived the creation of the pselect syscall (no atomicity in signal mask set/reset). Using it as generic implementation is counterproductive Also currently only microblaze uses it as fallback when used on kernel prior 3.15. This patch moves the generic implementation to a microblaze specific one, sets the generic internal as a ENOSYS, and cleanups the Linux generic implementation. The microblaze implementation mimics the previous Linux generic one, where it either uses pselect6 directly if __ASSUME_PSELECT or a first try pselect6 then the fallback otherwise. Checked on x86_64-linux-gnu and microblaze-linux-gnu.
2019-11-14 21:18:24 +00:00
/* Synchronous I/O multiplexing. Linux/microblaze version.
Update copyright dates with scripts/update-copyrights I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
2021-01-02 19:32:25 +00:00
Copyright (C) 2019-2021 Free Software Foundation, Inc.
misc: Set generic pselect as ENOSYS The generic pselect implementation has the very specific race condition that motived the creation of the pselect syscall (no atomicity in signal mask set/reset). Using it as generic implementation is counterproductive Also currently only microblaze uses it as fallback when used on kernel prior 3.15. This patch moves the generic implementation to a microblaze specific one, sets the generic internal as a ENOSYS, and cleanups the Linux generic implementation. The microblaze implementation mimics the previous Linux generic one, where it either uses pselect6 directly if __ASSUME_PSELECT or a first try pselect6 then the fallback otherwise. Checked on x86_64-linux-gnu and microblaze-linux-gnu.
2019-11-14 21:18:24 +00:00
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
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <signal.h>
#include <time.h>
#include <sys/poll.h>
#include <sysdep-cancel.h>
#ifndef __ASSUME_PSELECT
int
linux: Add time64 pselect support The syscall __NR_pselect6_time64 (32-bit) or __NR_pselect6 (64-bit) is used as default. For architectures with __ASSUME_TIME64_SYSCALLS the 32-bit fallback uses __NR_pselec6. To accomodate microblaze missing pselect6 support on kernel older than 3.15 the fallback is moved to its own function to the microblaze specific implementation can override it. Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-07-06 16:27:12 +00:00
__pselect32 (int nfds, fd_set *readfds, fd_set *writefds,
fd_set *exceptfds, const struct __timespec64 *timeout,
const sigset_t *sigmask)
misc: Set generic pselect as ENOSYS The generic pselect implementation has the very specific race condition that motived the creation of the pselect syscall (no atomicity in signal mask set/reset). Using it as generic implementation is counterproductive Also currently only microblaze uses it as fallback when used on kernel prior 3.15. This patch moves the generic implementation to a microblaze specific one, sets the generic internal as a ENOSYS, and cleanups the Linux generic implementation. The microblaze implementation mimics the previous Linux generic one, where it either uses pselect6 directly if __ASSUME_PSELECT or a first try pselect6 then the fallback otherwise. Checked on x86_64-linux-gnu and microblaze-linux-gnu.
2019-11-14 21:18:24 +00:00
{
/* The fallback uses 'select' which shows the race condition regarding
signal mask set/restore, requires two additional syscalls, and has
a worse timeout precision (microseconds instead of nanoseconds). */
linux: Add time64 pselect support The syscall __NR_pselect6_time64 (32-bit) or __NR_pselect6 (64-bit) is used as default. For architectures with __ASSUME_TIME64_SYSCALLS the 32-bit fallback uses __NR_pselec6. To accomodate microblaze missing pselect6 support on kernel older than 3.15 the fallback is moved to its own function to the microblaze specific implementation can override it. Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-07-06 16:27:12 +00:00
struct timeval tv32, *ptv32 = NULL;
misc: Set generic pselect as ENOSYS The generic pselect implementation has the very specific race condition that motived the creation of the pselect syscall (no atomicity in signal mask set/reset). Using it as generic implementation is counterproductive Also currently only microblaze uses it as fallback when used on kernel prior 3.15. This patch moves the generic implementation to a microblaze specific one, sets the generic internal as a ENOSYS, and cleanups the Linux generic implementation. The microblaze implementation mimics the previous Linux generic one, where it either uses pselect6 directly if __ASSUME_PSELECT or a first try pselect6 then the fallback otherwise. Checked on x86_64-linux-gnu and microblaze-linux-gnu.
2019-11-14 21:18:24 +00:00
if (timeout != NULL)
{
linux: Add time64 pselect support The syscall __NR_pselect6_time64 (32-bit) or __NR_pselect6 (64-bit) is used as default. For architectures with __ASSUME_TIME64_SYSCALLS the 32-bit fallback uses __NR_pselec6. To accomodate microblaze missing pselect6 support on kernel older than 3.15 the fallback is moved to its own function to the microblaze specific implementation can override it. Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-07-06 16:27:12 +00:00
if (! in_time_t_range (timeout->tv_sec)
|| ! valid_nanoseconds (timeout->tv_nsec))
misc: Set generic pselect as ENOSYS The generic pselect implementation has the very specific race condition that motived the creation of the pselect syscall (no atomicity in signal mask set/reset). Using it as generic implementation is counterproductive Also currently only microblaze uses it as fallback when used on kernel prior 3.15. This patch moves the generic implementation to a microblaze specific one, sets the generic internal as a ENOSYS, and cleanups the Linux generic implementation. The microblaze implementation mimics the previous Linux generic one, where it either uses pselect6 directly if __ASSUME_PSELECT or a first try pselect6 then the fallback otherwise. Checked on x86_64-linux-gnu and microblaze-linux-gnu.
2019-11-14 21:18:24 +00:00
{
__set_errno (EINVAL);
return -1;
}
linux: Add time64 pselect support The syscall __NR_pselect6_time64 (32-bit) or __NR_pselect6 (64-bit) is used as default. For architectures with __ASSUME_TIME64_SYSCALLS the 32-bit fallback uses __NR_pselec6. To accomodate microblaze missing pselect6 support on kernel older than 3.15 the fallback is moved to its own function to the microblaze specific implementation can override it. Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-07-06 16:27:12 +00:00
tv32 = valid_timespec64_to_timeval (*timeout);
ptv32 = &tv32;
misc: Set generic pselect as ENOSYS The generic pselect implementation has the very specific race condition that motived the creation of the pselect syscall (no atomicity in signal mask set/reset). Using it as generic implementation is counterproductive Also currently only microblaze uses it as fallback when used on kernel prior 3.15. This patch moves the generic implementation to a microblaze specific one, sets the generic internal as a ENOSYS, and cleanups the Linux generic implementation. The microblaze implementation mimics the previous Linux generic one, where it either uses pselect6 directly if __ASSUME_PSELECT or a first try pselect6 then the fallback otherwise. Checked on x86_64-linux-gnu and microblaze-linux-gnu.
2019-11-14 21:18:24 +00:00
}
sigset_t savemask;
if (sigmask != NULL)
__sigprocmask (SIG_SETMASK, sigmask, &savemask);
/* select itself is a cancellation entrypoint. */
linux: Add time64 pselect support The syscall __NR_pselect6_time64 (32-bit) or __NR_pselect6 (64-bit) is used as default. For architectures with __ASSUME_TIME64_SYSCALLS the 32-bit fallback uses __NR_pselec6. To accomodate microblaze missing pselect6 support on kernel older than 3.15 the fallback is moved to its own function to the microblaze specific implementation can override it. Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-07-06 16:27:12 +00:00
int ret = __select (nfds, readfds, writefds, exceptfds, ptv32);
misc: Set generic pselect as ENOSYS The generic pselect implementation has the very specific race condition that motived the creation of the pselect syscall (no atomicity in signal mask set/reset). Using it as generic implementation is counterproductive Also currently only microblaze uses it as fallback when used on kernel prior 3.15. This patch moves the generic implementation to a microblaze specific one, sets the generic internal as a ENOSYS, and cleanups the Linux generic implementation. The microblaze implementation mimics the previous Linux generic one, where it either uses pselect6 directly if __ASSUME_PSELECT or a first try pselect6 then the fallback otherwise. Checked on x86_64-linux-gnu and microblaze-linux-gnu.
2019-11-14 21:18:24 +00:00
if (sigmask != NULL)
__sigprocmask (SIG_SETMASK, &savemask, NULL);
return ret;
}
linux: Add time64 pselect support The syscall __NR_pselect6_time64 (32-bit) or __NR_pselect6 (64-bit) is used as default. For architectures with __ASSUME_TIME64_SYSCALLS the 32-bit fallback uses __NR_pselec6. To accomodate microblaze missing pselect6 support on kernel older than 3.15 the fallback is moved to its own function to the microblaze specific implementation can override it. Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-07-06 16:27:12 +00:00
#endif /* __ASSUME_PSELECT */
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