1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * Debugger co-routine context support. kmdb co-routines are essentially the 29 * same as the ones used by mdb, with the exception that we allocate the stack 30 * for the co-routine from our heap. 31 */ 32 33 #include <kmdb/kmdb_context_impl.h> 34 #include <mdb/mdb_modapi.h> 35 #include <mdb/mdb_debug.h> 36 #include <mdb/mdb_err.h> 37 #include <mdb/mdb_umem.h> 38 #include <mdb/mdb.h> 39 40 #include <sys/types.h> 41 42 #include <ucontext.h> 43 #include <setjmp.h> 44 45 static void 46 context_init(mdb_context_t *volatile c) 47 { 48 c->ctx_status = c->ctx_func(); 49 ASSERT(c->ctx_resumes > 0); 50 longjmp(c->ctx_pcb, 1); 51 } 52 53 mdb_context_t * 54 mdb_context_create(int (*func)(void)) 55 { 56 mdb_context_t *c = mdb_zalloc(sizeof (mdb_context_t), UM_NOSLEEP); 57 size_t pagesize = mdb.m_pagesize; 58 59 if (c == NULL) 60 return (NULL); 61 62 c->ctx_func = func; 63 c->ctx_stacksize = pagesize * 4; 64 c->ctx_stack = mdb_alloc_align(c->ctx_stacksize, pagesize, UM_NOSLEEP); 65 66 if (c->ctx_stack == NULL) { 67 mdb_free(c, sizeof (mdb_context_t)); 68 return (NULL); 69 } 70 71 kmdb_makecontext(&c->ctx_uc, (void (*)(void *))context_init, c, 72 c->ctx_stack, c->ctx_stacksize); 73 74 return (c); 75 } 76 77 void 78 mdb_context_destroy(mdb_context_t *c) 79 { 80 mdb_free_align(c->ctx_stack, c->ctx_stacksize); 81 mdb_free(c, sizeof (mdb_context_t)); 82 } 83 84 void 85 mdb_context_switch(mdb_context_t *c) 86 { 87 if (setjmp(c->ctx_pcb) == 0 && kmdb_setcontext(&c->ctx_uc) == -1) 88 fail("failed to change context to %p", (void *)c); 89 else 90 fail("unexpectedly returned from context %p", (void *)c); 91 } 92 93 jmp_buf * 94 mdb_context_getpcb(mdb_context_t *c) 95 { 96 c->ctx_resumes++; 97 return (&c->ctx_pcb); 98 } 99