1da673940SJordan Gordeev /*
2da673940SJordan Gordeev * Copyright (c) 2006 The DragonFly Project. All rights reserved.
3da673940SJordan Gordeev *
4da673940SJordan Gordeev * This code is derived from software contributed to The DragonFly Project
5da673940SJordan Gordeev * by Matthew Dillon <dillon@backplane.com>
6da673940SJordan Gordeev *
7da673940SJordan Gordeev * Redistribution and use in source and binary forms, with or without
8da673940SJordan Gordeev * modification, are permitted provided that the following conditions
9da673940SJordan Gordeev * are met:
10da673940SJordan Gordeev *
11da673940SJordan Gordeev * 1. Redistributions of source code must retain the above copyright
12da673940SJordan Gordeev * notice, this list of conditions and the following disclaimer.
13da673940SJordan Gordeev * 2. Redistributions in binary form must reproduce the above copyright
14da673940SJordan Gordeev * notice, this list of conditions and the following disclaimer in
15da673940SJordan Gordeev * the documentation and/or other materials provided with the
16da673940SJordan Gordeev * distribution.
17da673940SJordan Gordeev * 3. Neither the name of The DragonFly Project nor the names of its
18da673940SJordan Gordeev * contributors may be used to endorse or promote products derived
19da673940SJordan Gordeev * from this software without specific, prior written permission.
20da673940SJordan Gordeev *
21da673940SJordan Gordeev * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22da673940SJordan Gordeev * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23da673940SJordan Gordeev * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24da673940SJordan Gordeev * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25da673940SJordan Gordeev * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26da673940SJordan Gordeev * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27da673940SJordan Gordeev * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28da673940SJordan Gordeev * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29da673940SJordan Gordeev * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30da673940SJordan Gordeev * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31da673940SJordan Gordeev * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32da673940SJordan Gordeev * SUCH DAMAGE.
33da673940SJordan Gordeev */
34da673940SJordan Gordeev
35da673940SJordan Gordeev #ifndef _MACHINE_THREAD_H_
36da673940SJordan Gordeev #define _MACHINE_THREAD_H_
37da673940SJordan Gordeev
38da673940SJordan Gordeev #include <machine/vframe.h>
39da673940SJordan Gordeev #include <machine/npx.h>
40da673940SJordan Gordeev
41da673940SJordan Gordeev struct md_thread {
42da673940SJordan Gordeev unsigned int mtd_unused; /* used to be mtd_cpl */
43da673940SJordan Gordeev union savefpu *mtd_savefpu; /* pointer to current fpu context */
44da673940SJordan Gordeev struct vextframe mtd_savevext;
45da673940SJordan Gordeev };
46da673940SJordan Gordeev
47da673940SJordan Gordeev #ifdef _KERNEL
48da673940SJordan Gordeev
49da673940SJordan Gordeev #define td_savefpu td_mach.mtd_savefpu
50da673940SJordan Gordeev #define td_tls td_mach.mtd_savevext.vx_tls
51da673940SJordan Gordeev #define td_savevext td_mach.mtd_savevext
52da673940SJordan Gordeev
53da673940SJordan Gordeev /*
54da673940SJordan Gordeev * mycpu() retrieves the base of the current cpu's globaldata structure.
55da673940SJordan Gordeev * Note that it is *NOT* volatile, meaning that the value may be cached by
56da673940SJordan Gordeev * GCC. We have to force a dummy memory reference so gcc does not cache
57da673940SJordan Gordeev * the gd pointer across a procedure call (which might block and cause us
58da673940SJordan Gordeev * to wakeup on a different cpu).
59da673940SJordan Gordeev *
60da673940SJordan Gordeev * Also note that in DragonFly a thread can be preempted, but only by an
61da673940SJordan Gordeev * interrupt thread and the original thread will resume after the
62da673940SJordan Gordeev * interrupt thread finishes or blocks. A thread cannot move to another
63da673940SJordan Gordeev * cpu preemptively or at all, in fact, while you are in the kernel, even
64da673940SJordan Gordeev * if you block.
65da673940SJordan Gordeev */
66da673940SJordan Gordeev
67da673940SJordan Gordeev struct globaldata;
68da673940SJordan Gordeev
69da673940SJordan Gordeev extern int __mycpu__dummy;
70da673940SJordan Gordeev
71da673940SJordan Gordeev static __inline
72da673940SJordan Gordeev struct globaldata *
_get_mycpu(void)73da673940SJordan Gordeev _get_mycpu(void)
74da673940SJordan Gordeev {
75da673940SJordan Gordeev struct globaldata *gd;
76da673940SJordan Gordeev
77da673940SJordan Gordeev __asm ("movq %%gs:globaldata,%0" : "=r" (gd) : "m"(__mycpu__dummy));
78da673940SJordan Gordeev return(gd);
79da673940SJordan Gordeev }
80da673940SJordan Gordeev
81da673940SJordan Gordeev #define mycpu _get_mycpu()
82da673940SJordan Gordeev #define mycpuid (_get_mycpu()->gd_cpuid)
83da673940SJordan Gordeev
84da673940SJordan Gordeev /*
85da673940SJordan Gordeev * note: curthread is never NULL, but curproc can be. Also note that
86da673940SJordan Gordeev * that only processes really use the PCB. Threads fill in some fields
87da673940SJordan Gordeev * but mostly store contextual data on the stack and do not use (much of)
88da673940SJordan Gordeev * the PCB.
89da673940SJordan Gordeev */
90da673940SJordan Gordeev #define curthread mycpu->gd_curthread
91da673940SJordan Gordeev #define curproc curthread->td_proc
92da673940SJordan Gordeev
93*eb8c4738Szrj void vkernel_yield(void);
94*eb8c4738Szrj
95da673940SJordan Gordeev #endif /* _KERNEL */
96da673940SJordan Gordeev
97da673940SJordan Gordeev #endif /* !_MACHINE_THREAD_H_ */
98