diff options
Diffstat (limited to 'kernel/arch/x86_64/threadspfunc.S')
| -rw-r--r-- | kernel/arch/x86_64/threadspfunc.S | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/kernel/arch/x86_64/threadspfunc.S b/kernel/arch/x86_64/threadspfunc.S new file mode 100644 index 000000000000..c939f36b408a --- /dev/null +++ b/kernel/arch/x86_64/threadspfunc.S @@ -0,0 +1,54 @@ +/* $NetBSD: threadspfunc.S,v 1.2 2025/04/21 12:06:08 riastradh Exp $ */ + +/*- + * Copyright (c) 2025 The NetBSD Foundation, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#define _LOCORE + +#include <machine/asm.h> + +RCSID("$NetBSD: threadspfunc.S,v 1.2 2025/04/21 12:06:08 riastradh Exp $") + +/* + * void *threadspfunc(void *cookie@rdi) + * + * pthread_create(3) function. Return the stack pointer on entry. + */ +ENTRY(threadspfunc) + /* + * `The end of the input argument area shall be aligned on a + * [16-byte] boundary. In other words, the value of (%rsp + 8) + * is always a multiple of 16 when control is transferred to + * the function entry point.' + * + * To make it convenient for t_signal_and_sp.c, we subtract 8 + * from %rsp in order to get something congruent to zero modulo + * the stack alignemnt. + */ + movq %rsp,%rax + addq $-8,%rax + ret +END(threadspfunc) |