1 /* 2 * Copyright (c) 2003 Matt Dillon <dillon@backplane.com>, All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * Machine independant code should not directly include this file. 26 * 27 * $DragonFly: src/sys/platform/pc64/include/thread.h,v 1.2 2007/09/23 04:29:31 yanyh Exp $ 28 */ 29 30 #ifndef _MACHINE_THREAD_H_ 31 #define _MACHINE_THREAD_H_ 32 33 #ifndef _MACHINE_SEGMENTS_H_ 34 #include <machine/segments.h> 35 #endif 36 37 struct md_thread { 38 unsigned int mtd_cpl; 39 union savefpu *mtd_savefpu; 40 struct savetls mtd_savetls; 41 }; 42 43 #ifdef _KERNEL 44 45 #define td_cpl td_mach.mtd_cpl 46 #define td_tls td_mach.mtd_savetls 47 #define td_savefpu td_mach.mtd_savefpu 48 49 /* 50 * mycpu() retrieves the base of the current cpu's globaldata structure. 51 * Note that it is *NOT* volatile, meaning that the value may be cached by 52 * GCC. We have to force a dummy memory reference so gcc does not cache 53 * the gd pointer across a procedure call (which might block and cause us 54 * to wakeup on a different cpu). 55 * 56 * Also note that in DragonFly a thread can be preempted, but it cannot 57 * move to another cpu preemptively so the 'gd' pointer is good until you 58 * block. 59 */ 60 61 struct globaldata; 62 63 extern int __mycpu__dummy; 64 65 static __inline 66 struct globaldata * 67 _get_mycpu(void) 68 { 69 struct globaldata *gd; 70 71 __asm ("movq %%fs:globaldata,%0" : "=r" (gd) : "m"(__mycpu__dummy)); 72 return(gd); 73 } 74 75 #define mycpu _get_mycpu() 76 77 #ifdef SMP 78 #define mycpuid (_get_mycpu()->gd_cpuid) 79 #else 80 #define mycpuid 0 81 #endif 82 83 /* 84 * note: curthread is never NULL, but curproc can be. Also note that 85 * in DragonFly, the current pcb is stored in the thread structure. 86 */ 87 #define curthread mycpu->gd_curthread 88 #define curproc curthread->td_proc 89 90 #endif /* _KERNEL */ 91 92 #endif /* !_MACHINE_THREAD_H_ */ 93