[v4,09/13] or1k: Linux ABI

  ---
 sysdeps/or1k/nptl/pthreaddef.h                |  36 ++++++
 sysdeps/unix/sysv/linux/or1k/bits/procfs.h    |  38 ++++++
 sysdeps/unix/sysv/linux/or1k/getcontext.S     |  72 +++++++++++
 sysdeps/unix/sysv/linux/or1k/makecontext.c    |  77 ++++++++++++
 sysdeps/unix/sysv/linux/or1k/setcontext.S     | 108 ++++++++++++++++
 sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h |  28 +++++
 sysdeps/unix/sysv/linux/or1k/swapcontext.S    | 116 ++++++++++++++++++
 sysdeps/unix/sysv/linux/or1k/sys/ucontext.h   |  53 ++++++++
 sysdeps/unix/sysv/linux/or1k/sys/user.h       |   1 +
 sysdeps/unix/sysv/linux/or1k/ucontext_i.sym   |  26 ++++
 10 files changed, 555 insertions(+)
 create mode 100644 sysdeps/or1k/nptl/pthreaddef.h
 create mode 100644 sysdeps/unix/sysv/linux/or1k/bits/procfs.h
 create mode 100644 sysdeps/unix/sysv/linux/or1k/getcontext.S
 create mode 100644 sysdeps/unix/sysv/linux/or1k/makecontext.c
 create mode 100644 sysdeps/unix/sysv/linux/or1k/setcontext.S
 create mode 100644 sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h
 create mode 100644 sysdeps/unix/sysv/linux/or1k/swapcontext.S
 create mode 100644 sysdeps/unix/sysv/linux/or1k/sys/ucontext.h
 create mode 100644 sysdeps/unix/sysv/linux/or1k/sys/user.h
 create mode 100644 sysdeps/unix/sysv/linux/or1k/ucontext_i.sym
  

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

On 29/12/2021 01:42, Stafford Horne via Libc-alpha wrote:
> ---
>  sysdeps/or1k/nptl/pthreaddef.h                |  36 ++++++
>  sysdeps/unix/sysv/linux/or1k/bits/procfs.h    |  38 ++++++
>  sysdeps/unix/sysv/linux/or1k/getcontext.S     |  72 +++++++++++
>  sysdeps/unix/sysv/linux/or1k/makecontext.c    |  77 ++++++++++++
>  sysdeps/unix/sysv/linux/or1k/setcontext.S     | 108 ++++++++++++++++
>  sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h |  28 +++++
>  sysdeps/unix/sysv/linux/or1k/swapcontext.S    | 116 ++++++++++++++++++
>  sysdeps/unix/sysv/linux/or1k/sys/ucontext.h   |  53 ++++++++
>  sysdeps/unix/sysv/linux/or1k/sys/user.h       |   1 +
>  sysdeps/unix/sysv/linux/or1k/ucontext_i.sym   |  26 ++++
>  10 files changed, 555 insertions(+)
>  create mode 100644 sysdeps/or1k/nptl/pthreaddef.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/bits/procfs.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/getcontext.S
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/makecontext.c
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/setcontext.S
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/swapcontext.S
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/sys/ucontext.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/sys/user.h
>  create mode 100644 sysdeps/unix/sysv/linux/or1k/ucontext_i.sym
> 
> diff --git a/sysdeps/or1k/nptl/pthreaddef.h b/sysdeps/or1k/nptl/pthreaddef.h
> new file mode 100644
> index 0000000000..9cfb5af877
> --- /dev/null
> +++ b/sysdeps/or1k/nptl/pthreaddef.h
> @@ -0,0 +1,36 @@
> +/* pthread machine parameter definitions.  OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +/* Default stack size.  */
> +#define ARCH_STACK_DEFAULT_SIZE (2 * 1024 * 1024)
> +
> +/* Minimum guard size.  */
> +#define ARCH_MIN_GUARD_SIZE 0
> +
> +/* Required stack pointer alignment at beginning.  */
> +#define STACK_ALIGN 4
> +
> +/* Minimal stack size after allocating thread descriptor and guard size.  */
> +#define MINIMAL_REST_STACK 2048
> +
> +/* Alignment requirement for TCB.  Needs to be >= to STACK_ALIGN.  */
> +#define TCB_ALIGNMENT 32
> +
> +/* Location of current stack frame.  */
> +#define CURRENT_STACK_FRAME __builtin_frame_address (0)
> diff --git a/sysdeps/unix/sysv/linux/or1k/bits/procfs.h b/sysdeps/unix/sysv/linux/or1k/bits/procfs.h
> new file mode 100644
> index 0000000000..b50c92efb1
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/bits/procfs.h
> @@ -0,0 +1,38 @@
> +/* Types for registers for sys/procfs.h.  OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#ifndef _SYS_PROCFS_H
> +# error "Never include <bits/procfs.h> directly; use <sys/procfs.h> instead."
> +#endif
> +
> +#include <sys/ucontext.h>
> +
> +#define ELF_NGREG __NGREG
> +
> +/* Type for a general-purpose register.  */
> +typedef unsigned long int elf_greg_t;
> +
> +/* And the array of general-purpose registers.  We could have used `struct
> +   user_regs' directly, but tradition says that the register set is an array,
> +   which does have some peculiar semantics, so leave it that way.
> +   GDB uses this for prtrace GETREGSET, on OpenRISC the regset contains 32
> +   gprs the PC and the SR, 34 longs.  */
> +typedef elf_greg_t elf_gregset_t[34];
> +
> +/* Register set for the floating-point registers.  */
> +typedef elf_greg_t elf_fpregset_t[32];
> diff --git a/sysdeps/unix/sysv/linux/or1k/getcontext.S b/sysdeps/unix/sysv/linux/or1k/getcontext.S
> new file mode 100644
> index 0000000000..4c2e64db7a
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/getcontext.S
> @@ -0,0 +1,72 @@
> +/* Save current context.  OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <sysdep.h>
> +#include "ucontext_i.h"
> +
> +/* int getcontext (ucontext_t *ucp)
> +
> +   Returns 0 on success -1 and errno on failure.
> + */
> +	.text
> +ENTRY(__getcontext)
> +	/* Store r1, the stack pointer.  */
> +	l.sw	(UCONTEXT_MCONTEXT +  1*4)(r3), r1
> +	/* Store r2, the frame pointer.  */
> +	l.sw	(UCONTEXT_MCONTEXT +  2*4)(r3), r2
> +	/* Store r9, the link register.  */
> +	l.sw	(UCONTEXT_MCONTEXT +  9*4)(r3), r9
> +	/* Store r9 to reg[11] too, as we need two links for makecontext.  */
> +	l.sw	(UCONTEXT_MCONTEXT + 11*4)(r3), r9
> +	/* Store r10, the TLS register.  */
> +	l.sw	(UCONTEXT_MCONTEXT + 10*4)(r3), r10
> +	/* Store r14-r30 even, callee saved registers.  */
> +	l.sw	(UCONTEXT_MCONTEXT + 14*4)(r3), r14
> +	l.sw	(UCONTEXT_MCONTEXT + 16*4)(r3), r16
> +	l.sw	(UCONTEXT_MCONTEXT + 18*4)(r3), r18
> +	l.sw	(UCONTEXT_MCONTEXT + 20*4)(r3), r20
> +	l.sw	(UCONTEXT_MCONTEXT + 22*4)(r3), r22
> +	l.sw	(UCONTEXT_MCONTEXT + 24*4)(r3), r24
> +	l.sw	(UCONTEXT_MCONTEXT + 26*4)(r3), r26
> +	l.sw	(UCONTEXT_MCONTEXT + 28*4)(r3), r28
> +	l.sw	(UCONTEXT_MCONTEXT + 30*4)(r3), r30
> +
> +	/* Get signal mask.  */
> +	/* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */
> +	l.ori	r6, r0, _NSIG8
> +	l.addi	r5, r3, UCONTEXT_SIGMASK
> +	l.ori	r4, r0, 0
> +	l.ori	r3, r0, SIG_BLOCK
> +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> +	/* Do the syscall.  */
> +	l.sys	1
> +	 l.nop
> +
> +	/* if -4096 < ret < 0 holds, it's an error */
> +	l.sfgeui r11, 0xf001
> +	l.bf	1f
> +	 l.nop
> +
> +	l.jr	r9
> +	 l.ori r11, r0, 0
> +
> +1:	l.j	__syscall_error
> +	 l.ori	r3, r11, 0
> +
> +END(__getcontext)
> +weak_alias(__getcontext, getcontext)
> diff --git a/sysdeps/unix/sysv/linux/or1k/makecontext.c b/sysdeps/unix/sysv/linux/or1k/makecontext.c
> new file mode 100644
> index 0000000000..3dd4134a6b
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/makecontext.c
> @@ -0,0 +1,77 @@
> +/* Create new context.  OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <sysdep.h>
> +#include <stdarg.h>
> +#include <stdint.h>
> +#include <ucontext.h>
> +
> +/* makecontext sets up a stack and the registers for the
> +   user context.  The stack looks like this:
> +
> +		+-----------------------+
> +		| padding as required   |
> +		+-----------------------+
> +    sp ->       | parameters 7 to n     |
> +		+-----------------------+
> +
> +   The registers are set up like this:
> +     r3-r8  : parameters 1 to 6
> +     r14    : uc_link
> +     r1     : stack pointer
> +     r2     : frame pointer, set to NULL
> +*/
> +void
> +__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
> +{
> +  extern void __startcontext (void);
> +  unsigned long int *sp;
> +  va_list ap;
> +  int i;
> +
> +  sp = (unsigned long int *)
> +    ((uintptr_t) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
> +
> +  /* Allocate stack arguments.  */
> +  sp -= argc < 6 ? 0 : argc - 6;
> +
> +  /* Keep the stack aligned.  */
> +  sp = (unsigned long int *) (((uintptr_t) sp) & -4L);
> +
> +  /* Keep uc_link in r14.  */
> +  ucp->uc_mcontext.__gprs[14] = (uintptr_t) ucp->uc_link;
> +  /* Return address points to function __startcontext.  */
> +  ucp->uc_mcontext.__gprs[9] = (uintptr_t) &__startcontext;
> +  /* Frame pointer is null.  */
> +  ucp->uc_mcontext.__gprs[2] = (uintptr_t) 0;
> +  /* Restart in user-space starting at 'func'.  */
> +  ucp->uc_mcontext.__gprs[11] = (uintptr_t) func;
> +  /* Set stack pointer.  */
> +  ucp->uc_mcontext.__gprs[1] = (uintptr_t) sp;
> +
> +  va_start (ap, argc);
> +  for (i = 0; i < argc; ++i)
> +    if (i < 6)
> +      ucp->uc_mcontext.__gprs[i + 3] = va_arg (ap, unsigned long int);
> +    else
> +      sp[i - 6] = va_arg (ap, unsigned long int);
> +
> +  va_end (ap);
> +}
> +
> +weak_alias (__makecontext, makecontext)
> diff --git a/sysdeps/unix/sysv/linux/or1k/setcontext.S b/sysdeps/unix/sysv/linux/or1k/setcontext.S
> new file mode 100644
> index 0000000000..b4808d5422
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/setcontext.S
> @@ -0,0 +1,108 @@
> +/* Set current context.  OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <sysdep.h>
> +#include "ucontext_i.h"
> +
> +/* int setcontext (const ucontext_t *ucp) */
> +	.text
> +ENTRY(__setcontext)
> +	l.ori	r30, r3, 0
> +
> +	/* Restore signal mask.  */
> +	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG8) */
> +	l.ori	r6, r0, _NSIG8
> +	l.ori	r5, r0, 0
> +	l.addi	r4, r3, UCONTEXT_SIGMASK
> +	l.ori	r3, r0, SIG_SETMASK
> +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> +	/* Do the syscall.  */
> +	l.sys 1
> +	 l.nop
> +
> +	/* if -4096 < ret < 0 holds, it's an error */
> +	l.sfgeui r11, 0xf001
> +	l.bf	1f
> +	 l.nop
> +
> +	/* Restore argument registers, for the makecontext case.  */
> +	l.lwz	r3, (UCONTEXT_MCONTEXT +  3*4)(r30)
> +	l.lwz	r4, (UCONTEXT_MCONTEXT +  4*4)(r30)
> +	l.lwz	r5, (UCONTEXT_MCONTEXT +  5*4)(r30)
> +	l.lwz	r6, (UCONTEXT_MCONTEXT +  6*4)(r30)
> +	l.lwz	r7, (UCONTEXT_MCONTEXT +  7*4)(r30)
> +	l.lwz	r8, (UCONTEXT_MCONTEXT +  8*4)(r30)
> +
> +	/* Restore registers stored in getcontext.  */
> +	l.lwz	r1,  (UCONTEXT_MCONTEXT +  1*4)(r30)
> +	l.lwz	r2,  (UCONTEXT_MCONTEXT +  2*4)(r30)
> +	l.lwz	r9,  (UCONTEXT_MCONTEXT +  9*4)(r30)
> +	l.lwz	r10, (UCONTEXT_MCONTEXT + 10*4)(r30)
> +	l.lwz	r11, (UCONTEXT_MCONTEXT + 11*4)(r30)
> +	/* Restore r14-r30 even, callee saved registers.  */
> +	l.lwz	r14, (UCONTEXT_MCONTEXT + 14*4)(r30)
> +	l.lwz	r16, (UCONTEXT_MCONTEXT + 16*4)(r30)
> +	l.lwz	r18, (UCONTEXT_MCONTEXT + 18*4)(r30)
> +	l.lwz	r20, (UCONTEXT_MCONTEXT + 20*4)(r30)
> +	l.lwz	r22, (UCONTEXT_MCONTEXT + 22*4)(r30)
> +	l.lwz	r24, (UCONTEXT_MCONTEXT + 24*4)(r30)
> +	l.lwz	r26, (UCONTEXT_MCONTEXT + 26*4)(r30)
> +	l.lwz	r28, (UCONTEXT_MCONTEXT + 28*4)(r30)
> +	l.lwz	r30, (UCONTEXT_MCONTEXT + 30*4)(r30)
> +
> +	l.jr	r11
> +	 l.ori	r11, r0, 0
> +
> +1:	l.j	__syscall_error
> +	 l.ori	r3, r11, 0
> +
> +END (__setcontext)
> +weak_alias (__setcontext, setcontext)
> +
> +	/* We add a NOP here because when the unwinder is looking for the
> +	   enclosing function of the link register (r9) address FDE lookup will
> +	   use '$r9 - 1' finding setcontext which is wrong.  This is because in
> +	   makecontext we have set r9 to the start of &__startcontext.
> +
> +	   If this NOP did not exist the unwinder would repeatedly find
> +	   __setcontext's FDE in an infinite loop.  Modifiying/deleting the below
> +	   __startcontext's FDE has no help on this.  */
> +	l.nop
> +
> +ENTRY(__startcontext)
> +
> +	l.ori	r3, r14, 0
> +	l.sfeq	r3, r0
> +	/* If uc_link is not 0 resume there, otherwise exit.  */
> +	l.bnf	__setcontext
> +	 l.nop
> +
> +#ifdef SHARED
> +	/* Obtain a pointer to .got in r16 */
> +	l.jal	0x8
> +	 l.movhi r16, gotpchi(_GLOBAL_OFFSET_TABLE_-4)
> +	l.ori	r16, r16, gotpclo(_GLOBAL_OFFSET_TABLE_+0)
> +	l.add	r16, r16, r9
> +	l.lwz	r16, got(exit)(r16)
> +	l.jr	r16
> +#else
> +	l.j	exit
> +#endif
> +	 l.nop
> +
> +END(__startcontext)
> diff --git a/sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h b/sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h
> new file mode 100644
> index 0000000000..de94b59578
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h
> @@ -0,0 +1,28 @@
> +/* Profile counter helper to get PC from sigcontext.  OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#ifndef _SIGCONTEXTINFO_H
> +#define _SIGCONTEXTINFO_H
> +
> +static inline uintptr_t
> +sigcontext_get_pc (const ucontext_t *ctx)
> +{
> +  return ctx->uc_mcontext.__pc;
> +}
> +
> +#endif /* _SIGCONTEXTINFO_H */
> diff --git a/sysdeps/unix/sysv/linux/or1k/swapcontext.S b/sysdeps/unix/sysv/linux/or1k/swapcontext.S
> new file mode 100644
> index 0000000000..2acdc6d9bd
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/swapcontext.S
> @@ -0,0 +1,116 @@
> +/* Swap two contexts.  OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <sysdep.h>
> +#include "ucontext_i.h"
> +
> +/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */
> +	.text
> +ENTRY(__swapcontext)
> +
> +	/* Same as getcontext.  */
> +	/* Store r1, the stack pointer.  */
> +	l.sw	(UCONTEXT_MCONTEXT +  1*4)(r3), r1
> +	/* Store r2, the frame pointer.  */
> +	l.sw	(UCONTEXT_MCONTEXT +  2*4)(r3), r2
> +	/* Store r9, the link register.  */
> +	l.sw	(UCONTEXT_MCONTEXT +  9*4)(r3), r9
> +	/* Store r9 to reg[11] too, as we need two links for makecontext.  */
> +	l.sw	(UCONTEXT_MCONTEXT + 11*4)(r3), r9
> +	/* Store r10, the TLS register.  */
> +	l.sw	(UCONTEXT_MCONTEXT + 10*4)(r3), r10
> +	/* Store r14-r30 even, callee saved registers.  */
> +	l.sw	(UCONTEXT_MCONTEXT + 14*4)(r3), r14
> +	l.sw	(UCONTEXT_MCONTEXT + 16*4)(r3), r16
> +	l.sw	(UCONTEXT_MCONTEXT + 18*4)(r3), r18
> +	l.sw	(UCONTEXT_MCONTEXT + 20*4)(r3), r20
> +	l.sw	(UCONTEXT_MCONTEXT + 22*4)(r3), r22
> +	l.sw	(UCONTEXT_MCONTEXT + 24*4)(r3), r24
> +	l.sw	(UCONTEXT_MCONTEXT + 26*4)(r3), r26
> +	l.sw	(UCONTEXT_MCONTEXT + 28*4)(r3), r28
> +	l.sw	(UCONTEXT_MCONTEXT + 30*4)(r3), r30
> +
> +	/* Store ucp to non-argument syscall preserved register.  */
> +	l.ori	r30, r4, 0
> +
> +	/* Get signal mask.  */
> +	/* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */
> +	l.ori	r6, r0, _NSIG8
> +	l.addi	r5, r3, UCONTEXT_SIGMASK
> +	l.ori	r4, r0, 0
> +	l.ori	r3, r0, SIG_BLOCK
> +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> +	/* Do the syscall.  */
> +	l.sys	1
> +	 l.nop
> +
> +	/* if -4096 < ret < 0 holds, it's an error */
> +	l.sfgeui r11, 0xf001
> +	l.bf	1f
> +	 l.nop
> +
> +	/* Same as setcontext.  */
> +
> +	/* Restore signal mask.  */
> +	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG8) */
> +	l.ori	r6, r0, _NSIG8
> +	l.ori	r5, r0, 0
> +	l.addi	r4, r30, UCONTEXT_SIGMASK
> +	l.ori	r3, r0, SIG_SETMASK
> +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> +	/* Do the syscall.  */
> +	l.sys 1
> +	 l.nop
> +
> +	/* if -4096 < ret < 0 holds, it's an error */
> +	l.sfgeui r11, 0xf001
> +	l.bf	1f
> +	 l.nop
> +
> +	/* Restore argument registers, for the makecontext case.  */
> +	l.lwz	r3, (UCONTEXT_MCONTEXT +  3*4)(r30)
> +	l.lwz	r4, (UCONTEXT_MCONTEXT +  4*4)(r30)
> +	l.lwz	r5, (UCONTEXT_MCONTEXT +  5*4)(r30)
> +	l.lwz	r6, (UCONTEXT_MCONTEXT +  6*4)(r30)
> +	l.lwz	r7, (UCONTEXT_MCONTEXT +  7*4)(r30)
> +	l.lwz	r8, (UCONTEXT_MCONTEXT +  8*4)(r30)
> +
> +	/* Restore registers stored in getcontext.  */
> +	l.lwz	r1,  (UCONTEXT_MCONTEXT +  1*4)(r30)
> +	l.lwz	r2,  (UCONTEXT_MCONTEXT +  2*4)(r30)
> +	l.lwz	r9,  (UCONTEXT_MCONTEXT +  9*4)(r30)
> +	l.lwz	r10, (UCONTEXT_MCONTEXT + 10*4)(r30)
> +	l.lwz	r11, (UCONTEXT_MCONTEXT + 11*4)(r30)
> +	l.lwz	r14, (UCONTEXT_MCONTEXT + 14*4)(r30)
> +	l.lwz	r16, (UCONTEXT_MCONTEXT + 16*4)(r30)
> +	l.lwz	r18, (UCONTEXT_MCONTEXT + 18*4)(r30)
> +	l.lwz	r20, (UCONTEXT_MCONTEXT + 20*4)(r30)
> +	l.lwz	r22, (UCONTEXT_MCONTEXT + 22*4)(r30)
> +	l.lwz	r24, (UCONTEXT_MCONTEXT + 24*4)(r30)
> +	l.lwz	r26, (UCONTEXT_MCONTEXT + 26*4)(r30)
> +	l.lwz	r28, (UCONTEXT_MCONTEXT + 28*4)(r30)
> +	l.lwz	r30, (UCONTEXT_MCONTEXT + 30*4)(r30)
> +
> +	l.jr	r11
> +	 l.ori	r11, r0, 0
> +
> +1:	l.j	__syscall_error
> +	 l.ori	r3, r11, 0
> +
> +END (__swapcontext)
> +weak_alias (__swapcontext, swapcontext)
> diff --git a/sysdeps/unix/sysv/linux/or1k/sys/ucontext.h b/sysdeps/unix/sysv/linux/or1k/sys/ucontext.h
> new file mode 100644
> index 0000000000..c4aead8f93
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/sys/ucontext.h
> @@ -0,0 +1,53 @@
> +/* ucontext_t definition, OpenRISC version.
> +   Copyright (C) 2021 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
> +   <https://www.gnu.org/licenses/>.  */
> +
> +/* System V/OpenRISC compliant context switching support.  */
> +
> +#ifndef _SYS_UCONTEXT_H
> +#define _SYS_UCONTEXT_H	1
> +
> +#include <features.h>
> +
> +#include <bits/types/sigset_t.h>
> +#include <bits/types/stack_t.h>
> +
> +/* Number of general registers.  */
> +#define __NGREG	32
> +#ifdef __USE_MISC
> +# define NGREG	__NGREG
> +#endif
> +
> +/* Context to describe whole processor state.  */
> +typedef struct
> +  {
> +    unsigned long int __gprs[__NGREG];
> +    unsigned long int __pc;
> +    unsigned long int __sr;
> +  } mcontext_t;
> +
> +/* Userlevel context.  */
> +typedef struct ucontext_t
> +  {
> +    unsigned long int __uc_flags;
> +    struct ucontext_t *uc_link;
> +    stack_t uc_stack;
> +    mcontext_t uc_mcontext;
> +    sigset_t uc_sigmask;
> +  } ucontext_t;
> +
> +#endif /* sys/ucontext.h */
> diff --git a/sysdeps/unix/sysv/linux/or1k/sys/user.h b/sysdeps/unix/sysv/linux/or1k/sys/user.h
> new file mode 100644
> index 0000000000..c871f1a03d
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/sys/user.h
> @@ -0,0 +1 @@
> +/* This file is not needed, but in practice gdb might try to include it.  */
> diff --git a/sysdeps/unix/sysv/linux/or1k/ucontext_i.sym b/sysdeps/unix/sysv/linux/or1k/ucontext_i.sym
> new file mode 100644
> index 0000000000..a8d4db080f
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/or1k/ucontext_i.sym
> @@ -0,0 +1,26 @@
> +#include <inttypes.h>
> +#include <signal.h>
> +#include <stddef.h>
> +#include <sys/ucontext.h>
> +
> +-- Constants used by the rt_sigprocmask call.
> +
> +SIG_BLOCK
> +SIG_SETMASK
> +
> +_NSIG8				(_NSIG / 8)
> +
> +-- Offsets of the fields in the ucontext_t structure.
> +#define ucontext(member)	offsetof (ucontext_t, member)
> +#define stack(member)		ucontext (uc_stack.member)
> +
> +UCONTEXT_LINK			ucontext (uc_link)
> +UCONTEXT_STACK			ucontext (uc_stack)
> +UCONTEXT_MCONTEXT		ucontext (uc_mcontext)
> +UCONTEXT_SIGMASK		ucontext (uc_sigmask)
> +
> +STACK_SP			stack (ss_sp)
> +STACK_SIZE			stack (ss_size)
> +STACK_FLAGS			stack (ss_flags)
> +
> +UCONTEXT_SIZE			sizeof (ucontext_t)
  

On Mon, Jan 03, 2022 at 03:23:58PM -0300, Adhemerval Zanella wrote:
> LGTM, thanks.
> 
> Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Thank you.

> On 29/12/2021 01:42, Stafford Horne via Libc-alpha wrote:
> > ---
> >  sysdeps/or1k/nptl/pthreaddef.h                |  36 ++++++
> >  sysdeps/unix/sysv/linux/or1k/bits/procfs.h    |  38 ++++++
> >  sysdeps/unix/sysv/linux/or1k/getcontext.S     |  72 +++++++++++
> >  sysdeps/unix/sysv/linux/or1k/makecontext.c    |  77 ++++++++++++
> >  sysdeps/unix/sysv/linux/or1k/setcontext.S     | 108 ++++++++++++++++
> >  sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h |  28 +++++
> >  sysdeps/unix/sysv/linux/or1k/swapcontext.S    | 116 ++++++++++++++++++
> >  sysdeps/unix/sysv/linux/or1k/sys/ucontext.h   |  53 ++++++++
> >  sysdeps/unix/sysv/linux/or1k/sys/user.h       |   1 +
> >  sysdeps/unix/sysv/linux/or1k/ucontext_i.sym   |  26 ++++
> >  10 files changed, 555 insertions(+)
> >  create mode 100644 sysdeps/or1k/nptl/pthreaddef.h
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/bits/procfs.h
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/getcontext.S
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/makecontext.c
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/setcontext.S
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/swapcontext.S
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/sys/ucontext.h
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/sys/user.h
> >  create mode 100644 sysdeps/unix/sysv/linux/or1k/ucontext_i.sym
> > 
> > diff --git a/sysdeps/or1k/nptl/pthreaddef.h b/sysdeps/or1k/nptl/pthreaddef.h
> > new file mode 100644
> > index 0000000000..9cfb5af877
> > --- /dev/null
> > +++ b/sysdeps/or1k/nptl/pthreaddef.h
> > @@ -0,0 +1,36 @@
> > +/* pthread machine parameter definitions.  OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +/* Default stack size.  */
> > +#define ARCH_STACK_DEFAULT_SIZE (2 * 1024 * 1024)
> > +
> > +/* Minimum guard size.  */
> > +#define ARCH_MIN_GUARD_SIZE 0
> > +
> > +/* Required stack pointer alignment at beginning.  */
> > +#define STACK_ALIGN 4
> > +
> > +/* Minimal stack size after allocating thread descriptor and guard size.  */
> > +#define MINIMAL_REST_STACK 2048
> > +
> > +/* Alignment requirement for TCB.  Needs to be >= to STACK_ALIGN.  */
> > +#define TCB_ALIGNMENT 32
> > +
> > +/* Location of current stack frame.  */
> > +#define CURRENT_STACK_FRAME __builtin_frame_address (0)
> > diff --git a/sysdeps/unix/sysv/linux/or1k/bits/procfs.h b/sysdeps/unix/sysv/linux/or1k/bits/procfs.h
> > new file mode 100644
> > index 0000000000..b50c92efb1
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/bits/procfs.h
> > @@ -0,0 +1,38 @@
> > +/* Types for registers for sys/procfs.h.  OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#ifndef _SYS_PROCFS_H
> > +# error "Never include <bits/procfs.h> directly; use <sys/procfs.h> instead."
> > +#endif
> > +
> > +#include <sys/ucontext.h>
> > +
> > +#define ELF_NGREG __NGREG
> > +
> > +/* Type for a general-purpose register.  */
> > +typedef unsigned long int elf_greg_t;
> > +
> > +/* And the array of general-purpose registers.  We could have used `struct
> > +   user_regs' directly, but tradition says that the register set is an array,
> > +   which does have some peculiar semantics, so leave it that way.
> > +   GDB uses this for prtrace GETREGSET, on OpenRISC the regset contains 32
> > +   gprs the PC and the SR, 34 longs.  */
> > +typedef elf_greg_t elf_gregset_t[34];
> > +
> > +/* Register set for the floating-point registers.  */
> > +typedef elf_greg_t elf_fpregset_t[32];
> > diff --git a/sysdeps/unix/sysv/linux/or1k/getcontext.S b/sysdeps/unix/sysv/linux/or1k/getcontext.S
> > new file mode 100644
> > index 0000000000..4c2e64db7a
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/getcontext.S
> > @@ -0,0 +1,72 @@
> > +/* Save current context.  OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#include <sysdep.h>
> > +#include "ucontext_i.h"
> > +
> > +/* int getcontext (ucontext_t *ucp)
> > +
> > +   Returns 0 on success -1 and errno on failure.
> > + */
> > +	.text
> > +ENTRY(__getcontext)
> > +	/* Store r1, the stack pointer.  */
> > +	l.sw	(UCONTEXT_MCONTEXT +  1*4)(r3), r1
> > +	/* Store r2, the frame pointer.  */
> > +	l.sw	(UCONTEXT_MCONTEXT +  2*4)(r3), r2
> > +	/* Store r9, the link register.  */
> > +	l.sw	(UCONTEXT_MCONTEXT +  9*4)(r3), r9
> > +	/* Store r9 to reg[11] too, as we need two links for makecontext.  */
> > +	l.sw	(UCONTEXT_MCONTEXT + 11*4)(r3), r9
> > +	/* Store r10, the TLS register.  */
> > +	l.sw	(UCONTEXT_MCONTEXT + 10*4)(r3), r10
> > +	/* Store r14-r30 even, callee saved registers.  */
> > +	l.sw	(UCONTEXT_MCONTEXT + 14*4)(r3), r14
> > +	l.sw	(UCONTEXT_MCONTEXT + 16*4)(r3), r16
> > +	l.sw	(UCONTEXT_MCONTEXT + 18*4)(r3), r18
> > +	l.sw	(UCONTEXT_MCONTEXT + 20*4)(r3), r20
> > +	l.sw	(UCONTEXT_MCONTEXT + 22*4)(r3), r22
> > +	l.sw	(UCONTEXT_MCONTEXT + 24*4)(r3), r24
> > +	l.sw	(UCONTEXT_MCONTEXT + 26*4)(r3), r26
> > +	l.sw	(UCONTEXT_MCONTEXT + 28*4)(r3), r28
> > +	l.sw	(UCONTEXT_MCONTEXT + 30*4)(r3), r30
> > +
> > +	/* Get signal mask.  */
> > +	/* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */
> > +	l.ori	r6, r0, _NSIG8
> > +	l.addi	r5, r3, UCONTEXT_SIGMASK
> > +	l.ori	r4, r0, 0
> > +	l.ori	r3, r0, SIG_BLOCK
> > +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> > +	/* Do the syscall.  */
> > +	l.sys	1
> > +	 l.nop
> > +
> > +	/* if -4096 < ret < 0 holds, it's an error */
> > +	l.sfgeui r11, 0xf001
> > +	l.bf	1f
> > +	 l.nop
> > +
> > +	l.jr	r9
> > +	 l.ori r11, r0, 0
> > +
> > +1:	l.j	__syscall_error
> > +	 l.ori	r3, r11, 0
> > +
> > +END(__getcontext)
> > +weak_alias(__getcontext, getcontext)
> > diff --git a/sysdeps/unix/sysv/linux/or1k/makecontext.c b/sysdeps/unix/sysv/linux/or1k/makecontext.c
> > new file mode 100644
> > index 0000000000..3dd4134a6b
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/makecontext.c
> > @@ -0,0 +1,77 @@
> > +/* Create new context.  OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#include <sysdep.h>
> > +#include <stdarg.h>
> > +#include <stdint.h>
> > +#include <ucontext.h>
> > +
> > +/* makecontext sets up a stack and the registers for the
> > +   user context.  The stack looks like this:
> > +
> > +		+-----------------------+
> > +		| padding as required   |
> > +		+-----------------------+
> > +    sp ->       | parameters 7 to n     |
> > +		+-----------------------+
> > +
> > +   The registers are set up like this:
> > +     r3-r8  : parameters 1 to 6
> > +     r14    : uc_link
> > +     r1     : stack pointer
> > +     r2     : frame pointer, set to NULL
> > +*/
> > +void
> > +__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
> > +{
> > +  extern void __startcontext (void);
> > +  unsigned long int *sp;
> > +  va_list ap;
> > +  int i;
> > +
> > +  sp = (unsigned long int *)
> > +    ((uintptr_t) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
> > +
> > +  /* Allocate stack arguments.  */
> > +  sp -= argc < 6 ? 0 : argc - 6;
> > +
> > +  /* Keep the stack aligned.  */
> > +  sp = (unsigned long int *) (((uintptr_t) sp) & -4L);
> > +
> > +  /* Keep uc_link in r14.  */
> > +  ucp->uc_mcontext.__gprs[14] = (uintptr_t) ucp->uc_link;
> > +  /* Return address points to function __startcontext.  */
> > +  ucp->uc_mcontext.__gprs[9] = (uintptr_t) &__startcontext;
> > +  /* Frame pointer is null.  */
> > +  ucp->uc_mcontext.__gprs[2] = (uintptr_t) 0;
> > +  /* Restart in user-space starting at 'func'.  */
> > +  ucp->uc_mcontext.__gprs[11] = (uintptr_t) func;
> > +  /* Set stack pointer.  */
> > +  ucp->uc_mcontext.__gprs[1] = (uintptr_t) sp;
> > +
> > +  va_start (ap, argc);
> > +  for (i = 0; i < argc; ++i)
> > +    if (i < 6)
> > +      ucp->uc_mcontext.__gprs[i + 3] = va_arg (ap, unsigned long int);
> > +    else
> > +      sp[i - 6] = va_arg (ap, unsigned long int);
> > +
> > +  va_end (ap);
> > +}
> > +
> > +weak_alias (__makecontext, makecontext)
> > diff --git a/sysdeps/unix/sysv/linux/or1k/setcontext.S b/sysdeps/unix/sysv/linux/or1k/setcontext.S
> > new file mode 100644
> > index 0000000000..b4808d5422
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/setcontext.S
> > @@ -0,0 +1,108 @@
> > +/* Set current context.  OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#include <sysdep.h>
> > +#include "ucontext_i.h"
> > +
> > +/* int setcontext (const ucontext_t *ucp) */
> > +	.text
> > +ENTRY(__setcontext)
> > +	l.ori	r30, r3, 0
> > +
> > +	/* Restore signal mask.  */
> > +	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG8) */
> > +	l.ori	r6, r0, _NSIG8
> > +	l.ori	r5, r0, 0
> > +	l.addi	r4, r3, UCONTEXT_SIGMASK
> > +	l.ori	r3, r0, SIG_SETMASK
> > +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> > +	/* Do the syscall.  */
> > +	l.sys 1
> > +	 l.nop
> > +
> > +	/* if -4096 < ret < 0 holds, it's an error */
> > +	l.sfgeui r11, 0xf001
> > +	l.bf	1f
> > +	 l.nop
> > +
> > +	/* Restore argument registers, for the makecontext case.  */
> > +	l.lwz	r3, (UCONTEXT_MCONTEXT +  3*4)(r30)
> > +	l.lwz	r4, (UCONTEXT_MCONTEXT +  4*4)(r30)
> > +	l.lwz	r5, (UCONTEXT_MCONTEXT +  5*4)(r30)
> > +	l.lwz	r6, (UCONTEXT_MCONTEXT +  6*4)(r30)
> > +	l.lwz	r7, (UCONTEXT_MCONTEXT +  7*4)(r30)
> > +	l.lwz	r8, (UCONTEXT_MCONTEXT +  8*4)(r30)
> > +
> > +	/* Restore registers stored in getcontext.  */
> > +	l.lwz	r1,  (UCONTEXT_MCONTEXT +  1*4)(r30)
> > +	l.lwz	r2,  (UCONTEXT_MCONTEXT +  2*4)(r30)
> > +	l.lwz	r9,  (UCONTEXT_MCONTEXT +  9*4)(r30)
> > +	l.lwz	r10, (UCONTEXT_MCONTEXT + 10*4)(r30)
> > +	l.lwz	r11, (UCONTEXT_MCONTEXT + 11*4)(r30)
> > +	/* Restore r14-r30 even, callee saved registers.  */
> > +	l.lwz	r14, (UCONTEXT_MCONTEXT + 14*4)(r30)
> > +	l.lwz	r16, (UCONTEXT_MCONTEXT + 16*4)(r30)
> > +	l.lwz	r18, (UCONTEXT_MCONTEXT + 18*4)(r30)
> > +	l.lwz	r20, (UCONTEXT_MCONTEXT + 20*4)(r30)
> > +	l.lwz	r22, (UCONTEXT_MCONTEXT + 22*4)(r30)
> > +	l.lwz	r24, (UCONTEXT_MCONTEXT + 24*4)(r30)
> > +	l.lwz	r26, (UCONTEXT_MCONTEXT + 26*4)(r30)
> > +	l.lwz	r28, (UCONTEXT_MCONTEXT + 28*4)(r30)
> > +	l.lwz	r30, (UCONTEXT_MCONTEXT + 30*4)(r30)
> > +
> > +	l.jr	r11
> > +	 l.ori	r11, r0, 0
> > +
> > +1:	l.j	__syscall_error
> > +	 l.ori	r3, r11, 0
> > +
> > +END (__setcontext)
> > +weak_alias (__setcontext, setcontext)
> > +
> > +	/* We add a NOP here because when the unwinder is looking for the
> > +	   enclosing function of the link register (r9) address FDE lookup will
> > +	   use '$r9 - 1' finding setcontext which is wrong.  This is because in
> > +	   makecontext we have set r9 to the start of &__startcontext.
> > +
> > +	   If this NOP did not exist the unwinder would repeatedly find
> > +	   __setcontext's FDE in an infinite loop.  Modifiying/deleting the below
> > +	   __startcontext's FDE has no help on this.  */
> > +	l.nop
> > +
> > +ENTRY(__startcontext)
> > +
> > +	l.ori	r3, r14, 0
> > +	l.sfeq	r3, r0
> > +	/* If uc_link is not 0 resume there, otherwise exit.  */
> > +	l.bnf	__setcontext
> > +	 l.nop
> > +
> > +#ifdef SHARED
> > +	/* Obtain a pointer to .got in r16 */
> > +	l.jal	0x8
> > +	 l.movhi r16, gotpchi(_GLOBAL_OFFSET_TABLE_-4)
> > +	l.ori	r16, r16, gotpclo(_GLOBAL_OFFSET_TABLE_+0)
> > +	l.add	r16, r16, r9
> > +	l.lwz	r16, got(exit)(r16)
> > +	l.jr	r16
> > +#else
> > +	l.j	exit
> > +#endif
> > +	 l.nop
> > +
> > +END(__startcontext)
> > diff --git a/sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h b/sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h
> > new file mode 100644
> > index 0000000000..de94b59578
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/sigcontextinfo.h
> > @@ -0,0 +1,28 @@
> > +/* Profile counter helper to get PC from sigcontext.  OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#ifndef _SIGCONTEXTINFO_H
> > +#define _SIGCONTEXTINFO_H
> > +
> > +static inline uintptr_t
> > +sigcontext_get_pc (const ucontext_t *ctx)
> > +{
> > +  return ctx->uc_mcontext.__pc;
> > +}
> > +
> > +#endif /* _SIGCONTEXTINFO_H */
> > diff --git a/sysdeps/unix/sysv/linux/or1k/swapcontext.S b/sysdeps/unix/sysv/linux/or1k/swapcontext.S
> > new file mode 100644
> > index 0000000000..2acdc6d9bd
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/swapcontext.S
> > @@ -0,0 +1,116 @@
> > +/* Swap two contexts.  OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +#include <sysdep.h>
> > +#include "ucontext_i.h"
> > +
> > +/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */
> > +	.text
> > +ENTRY(__swapcontext)
> > +
> > +	/* Same as getcontext.  */
> > +	/* Store r1, the stack pointer.  */
> > +	l.sw	(UCONTEXT_MCONTEXT +  1*4)(r3), r1
> > +	/* Store r2, the frame pointer.  */
> > +	l.sw	(UCONTEXT_MCONTEXT +  2*4)(r3), r2
> > +	/* Store r9, the link register.  */
> > +	l.sw	(UCONTEXT_MCONTEXT +  9*4)(r3), r9
> > +	/* Store r9 to reg[11] too, as we need two links for makecontext.  */
> > +	l.sw	(UCONTEXT_MCONTEXT + 11*4)(r3), r9
> > +	/* Store r10, the TLS register.  */
> > +	l.sw	(UCONTEXT_MCONTEXT + 10*4)(r3), r10
> > +	/* Store r14-r30 even, callee saved registers.  */
> > +	l.sw	(UCONTEXT_MCONTEXT + 14*4)(r3), r14
> > +	l.sw	(UCONTEXT_MCONTEXT + 16*4)(r3), r16
> > +	l.sw	(UCONTEXT_MCONTEXT + 18*4)(r3), r18
> > +	l.sw	(UCONTEXT_MCONTEXT + 20*4)(r3), r20
> > +	l.sw	(UCONTEXT_MCONTEXT + 22*4)(r3), r22
> > +	l.sw	(UCONTEXT_MCONTEXT + 24*4)(r3), r24
> > +	l.sw	(UCONTEXT_MCONTEXT + 26*4)(r3), r26
> > +	l.sw	(UCONTEXT_MCONTEXT + 28*4)(r3), r28
> > +	l.sw	(UCONTEXT_MCONTEXT + 30*4)(r3), r30
> > +
> > +	/* Store ucp to non-argument syscall preserved register.  */
> > +	l.ori	r30, r4, 0
> > +
> > +	/* Get signal mask.  */
> > +	/* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */
> > +	l.ori	r6, r0, _NSIG8
> > +	l.addi	r5, r3, UCONTEXT_SIGMASK
> > +	l.ori	r4, r0, 0
> > +	l.ori	r3, r0, SIG_BLOCK
> > +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> > +	/* Do the syscall.  */
> > +	l.sys	1
> > +	 l.nop
> > +
> > +	/* if -4096 < ret < 0 holds, it's an error */
> > +	l.sfgeui r11, 0xf001
> > +	l.bf	1f
> > +	 l.nop
> > +
> > +	/* Same as setcontext.  */
> > +
> > +	/* Restore signal mask.  */
> > +	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG8) */
> > +	l.ori	r6, r0, _NSIG8
> > +	l.ori	r5, r0, 0
> > +	l.addi	r4, r30, UCONTEXT_SIGMASK
> > +	l.ori	r3, r0, SIG_SETMASK
> > +	l.ori	r11, r0, SYS_ify (rt_sigprocmask)
> > +	/* Do the syscall.  */
> > +	l.sys 1
> > +	 l.nop
> > +
> > +	/* if -4096 < ret < 0 holds, it's an error */
> > +	l.sfgeui r11, 0xf001
> > +	l.bf	1f
> > +	 l.nop
> > +
> > +	/* Restore argument registers, for the makecontext case.  */
> > +	l.lwz	r3, (UCONTEXT_MCONTEXT +  3*4)(r30)
> > +	l.lwz	r4, (UCONTEXT_MCONTEXT +  4*4)(r30)
> > +	l.lwz	r5, (UCONTEXT_MCONTEXT +  5*4)(r30)
> > +	l.lwz	r6, (UCONTEXT_MCONTEXT +  6*4)(r30)
> > +	l.lwz	r7, (UCONTEXT_MCONTEXT +  7*4)(r30)
> > +	l.lwz	r8, (UCONTEXT_MCONTEXT +  8*4)(r30)
> > +
> > +	/* Restore registers stored in getcontext.  */
> > +	l.lwz	r1,  (UCONTEXT_MCONTEXT +  1*4)(r30)
> > +	l.lwz	r2,  (UCONTEXT_MCONTEXT +  2*4)(r30)
> > +	l.lwz	r9,  (UCONTEXT_MCONTEXT +  9*4)(r30)
> > +	l.lwz	r10, (UCONTEXT_MCONTEXT + 10*4)(r30)
> > +	l.lwz	r11, (UCONTEXT_MCONTEXT + 11*4)(r30)
> > +	l.lwz	r14, (UCONTEXT_MCONTEXT + 14*4)(r30)
> > +	l.lwz	r16, (UCONTEXT_MCONTEXT + 16*4)(r30)
> > +	l.lwz	r18, (UCONTEXT_MCONTEXT + 18*4)(r30)
> > +	l.lwz	r20, (UCONTEXT_MCONTEXT + 20*4)(r30)
> > +	l.lwz	r22, (UCONTEXT_MCONTEXT + 22*4)(r30)
> > +	l.lwz	r24, (UCONTEXT_MCONTEXT + 24*4)(r30)
> > +	l.lwz	r26, (UCONTEXT_MCONTEXT + 26*4)(r30)
> > +	l.lwz	r28, (UCONTEXT_MCONTEXT + 28*4)(r30)
> > +	l.lwz	r30, (UCONTEXT_MCONTEXT + 30*4)(r30)
> > +
> > +	l.jr	r11
> > +	 l.ori	r11, r0, 0
> > +
> > +1:	l.j	__syscall_error
> > +	 l.ori	r3, r11, 0
> > +
> > +END (__swapcontext)
> > +weak_alias (__swapcontext, swapcontext)
> > diff --git a/sysdeps/unix/sysv/linux/or1k/sys/ucontext.h b/sysdeps/unix/sysv/linux/or1k/sys/ucontext.h
> > new file mode 100644
> > index 0000000000..c4aead8f93
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/sys/ucontext.h
> > @@ -0,0 +1,53 @@
> > +/* ucontext_t definition, OpenRISC version.
> > +   Copyright (C) 2021 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
> > +   <https://www.gnu.org/licenses/>.  */
> > +
> > +/* System V/OpenRISC compliant context switching support.  */
> > +
> > +#ifndef _SYS_UCONTEXT_H
> > +#define _SYS_UCONTEXT_H	1
> > +
> > +#include <features.h>
> > +
> > +#include <bits/types/sigset_t.h>
> > +#include <bits/types/stack_t.h>
> > +
> > +/* Number of general registers.  */
> > +#define __NGREG	32
> > +#ifdef __USE_MISC
> > +# define NGREG	__NGREG
> > +#endif
> > +
> > +/* Context to describe whole processor state.  */
> > +typedef struct
> > +  {
> > +    unsigned long int __gprs[__NGREG];
> > +    unsigned long int __pc;
> > +    unsigned long int __sr;
> > +  } mcontext_t;
> > +
> > +/* Userlevel context.  */
> > +typedef struct ucontext_t
> > +  {
> > +    unsigned long int __uc_flags;
> > +    struct ucontext_t *uc_link;
> > +    stack_t uc_stack;
> > +    mcontext_t uc_mcontext;
> > +    sigset_t uc_sigmask;
> > +  } ucontext_t;
> > +
> > +#endif /* sys/ucontext.h */
> > diff --git a/sysdeps/unix/sysv/linux/or1k/sys/user.h b/sysdeps/unix/sysv/linux/or1k/sys/user.h
> > new file mode 100644
> > index 0000000000..c871f1a03d
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/sys/user.h
> > @@ -0,0 +1 @@
> > +/* This file is not needed, but in practice gdb might try to include it.  */
> > diff --git a/sysdeps/unix/sysv/linux/or1k/ucontext_i.sym b/sysdeps/unix/sysv/linux/or1k/ucontext_i.sym
> > new file mode 100644
> > index 0000000000..a8d4db080f
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/or1k/ucontext_i.sym
> > @@ -0,0 +1,26 @@
> > +#include <inttypes.h>
> > +#include <signal.h>
> > +#include <stddef.h>
> > +#include <sys/ucontext.h>
> > +
> > +-- Constants used by the rt_sigprocmask call.
> > +
> > +SIG_BLOCK
> > +SIG_SETMASK
> > +
> > +_NSIG8				(_NSIG / 8)
> > +
> > +-- Offsets of the fields in the ucontext_t structure.
> > +#define ucontext(member)	offsetof (ucontext_t, member)
> > +#define stack(member)		ucontext (uc_stack.member)
> > +
> > +UCONTEXT_LINK			ucontext (uc_link)
> > +UCONTEXT_STACK			ucontext (uc_stack)
> > +UCONTEXT_MCONTEXT		ucontext (uc_mcontext)
> > +UCONTEXT_SIGMASK		ucontext (uc_sigmask)
> > +
> > +STACK_SP			stack (ss_sp)
> > +STACK_SIZE			stack (ss_size)
> > +STACK_FLAGS			stack (ss_flags)
> > +
> > +UCONTEXT_SIZE			sizeof (ucontext_t)