mono/metadata/sgen-os-mach.c

   1 /*
   2  * sgen-os-mach.c: Mach-OS support.
   3  *
   4  * Author:
   5  *      Paolo Molaro (lupus@ximian.com)
   6  *      Mark Probst (mprobst@novell.com)
   7  *      Geoff Norton (gnorton@novell.com)
   8  *
   9  * Copyright 2010 Novell, Inc (http://www.novell.com)
  10  * Copyright (C) 2012 Xamarin Inc
  11  *
  12  * This library is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Library General Public
  14  * License 2.0 as published by the Free Software Foundation;
  15  *
  16  * This library is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * Library General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Library General Public
  22  * License 2.0 along with this library; if not, write to the Free
  23  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  24  */
  25
  26 #include "config.h"
  27 #ifdef HAVE_SGEN_GC
  28
  29
  30 #include <glib.h>
  31 #include "metadata/sgen-gc.h"
  32 #include "metadata/sgen-archdep.h"
  33 #include "metadata/sgen-protocol.h"
  34 #include "metadata/object-internals.h"
  35 #include "metadata/gc-internal.h"
  36
  37 #if defined(__MACH__)
  38 #include "utils/mach-support.h"
  39 #endif
  40
  41 #if defined(__MACH__) && MONO_MACH_ARCH_SUPPORTED
  42 gboolean
  43 sgen_resume_thread (SgenThreadInfo *info)
  44 {
  45         return thread_resume (info->info.native_handle) == KERN_SUCCESS;
  46 }
  47
  48 gboolean
  49 sgen_suspend_thread (SgenThreadInfo *info)
  50 {
  51         mach_msg_type_number_t num_state;
  52         thread_state_t state;
  53         kern_return_t ret;
  54         ucontext_t ctx;
  55         mcontext_t mctx;
  56
  57         gpointer stack_start;
  58
  59         state = (thread_state_t) alloca (mono_mach_arch_get_thread_state_size ());
  60         mctx = (mcontext_t) alloca (mono_mach_arch_get_mcontext_size ());
  61
  62         ret = thread_suspend (info->info.native_handle);
  63         if (ret != KERN_SUCCESS)
  64                 return FALSE;
  65
  66         ret = mono_mach_arch_get_thread_state (info->info.native_handle, state, &num_state);
  67         if (ret != KERN_SUCCESS)
  68                 return FALSE;
  69
  70         mono_mach_arch_thread_state_to_mcontext (state, mctx);
  71         ctx.uc_mcontext = mctx;
  72
  73         info->stopped_domain = mono_thread_info_tls_get (info, TLS_KEY_DOMAIN);
  74         info->stopped_ip = (gpointer) mono_mach_arch_get_ip (state);
  75         info->stack_start = NULL;
  76         stack_start = (char*) mono_mach_arch_get_sp (state) - REDZONE_SIZE;
  77         /* If stack_start is not within the limits, then don't set it in info and we will be restarted. */
  78         if (stack_start >= info->stack_start_limit && info->stack_start <= info->stack_end) {
  79                 info->stack_start = stack_start;
  80
  81 #ifdef USE_MONO_CTX
  82                 mono_sigctx_to_monoctx (&ctx, &info->ctx);
  83 #else
  84                 ARCH_COPY_SIGCTX_REGS (&info->regs, &ctx);
  85 #endif
  86         } else {
  87                 g_assert (!info->stack_start);
  88         }
  89
  90         /* Notify the JIT */
  91         if (mono_gc_get_gc_callbacks ()->thread_suspend_func)
  92                 mono_gc_get_gc_callbacks ()->thread_suspend_func (info->runtime_data, &ctx, NULL);
  93
  94         SGEN_LOG (2, "thread %p stopped at %p stack_start=%p", (void*)(gsize)info->info.native_handle, info->stopped_ip, info->stack_start);
  95
  96         binary_protocol_thread_suspend ((gpointer)mono_thread_info_get_tid (info), info->stopped_ip);
  97
  98         return TRUE;
  99 }
 100
 101 void
 102 sgen_wait_for_suspend_ack (int count)
 103 {
 104     /* mach thread_resume is synchronous so we dont need to wait for them */
 105 }
 106
 107 /* LOCKING: assumes the GC lock is held */
 108 int
 109 sgen_thread_handshake (BOOL suspend)
 110 {
 111         SgenThreadInfo *cur_thread = mono_thread_info_current ();
 112         kern_return_t ret;
 113         SgenThreadInfo *info;
 114
 115         int count = 0;
 116
 117         FOREACH_THREAD_SAFE (info) {
 118                 if (info == cur_thread || sgen_is_worker_thread (mono_thread_info_get_tid (info)))
 119                         continue;
 120                 if (info->gc_disabled)
 121                         continue;
 122
 123                 if (suspend) {
 124                         if (!sgen_suspend_thread (info))
 125                                 continue;
 126                 } else {
 127                         ret = thread_resume (info->info.native_handle);
 128                         if (ret != KERN_SUCCESS)
 129                                 continue;
 130                 }
 131                 count ++;
 132         } END_FOREACH_THREAD_SAFE
 133         return count;
 134 }
 135
 136 void
 137 sgen_os_init (void)
 138 {
 139 }
 140
 141 int
 142 mono_gc_get_suspend_signal (void)
 143 {
 144         return -1;
 145 }
 146
 147 int
 148 mono_gc_get_restart_signal (void)
 149 {
 150         return -1;
 151 }
 152 #endif
 153 #endif