mono/utils/mono-threads-mach.c

   1 /**
   2  * \file
   3  * Low-level threading, mach version
   4  *
   5  * Author:
   6  *      Rodrigo Kumpera (kumpera@gmail.com)
   7  *
   8  * (C) 2011 Novell, Inc
   9  */
  10
  11 #include "config.h"
  12
  13 /* For pthread_main_np, pthread_get_stackaddr_np and pthread_get_stacksize_np */
  14 #if defined (__MACH__)
  15 #define _DARWIN_C_SOURCE 1
  16 #endif
  17
  18 #include <mono/utils/mono-threads.h>
  19 #include <mono/utils/mono-mmap.h>
  20
  21 #if defined (USE_MACH_BACKEND)
  22
  23 #include <mono/utils/mach-support.h>
  24 #include <mono/utils/mono-compiler.h>
  25 #include <mono/utils/mono-threads.h>
  26 #include <mono/utils/hazard-pointer.h>
  27 #include <mono/utils/mono-threads-coop.h>
  28 #include <mono/utils/mono-threads-debug.h>
  29
  30 void
  31 mono_threads_suspend_init (void)
  32 {
  33         mono_threads_init_dead_letter ();
  34 }
  35
  36 #if defined(HOST_WATCHOS)
  37
  38 gboolean
  39 mono_threads_suspend_begin_async_suspend (MonoThreadInfo *info, gboolean interrupt_kernel)
  40 {
  41         g_assert_not_reached ();
  42 }
  43
  44 gboolean
  45 mono_threads_suspend_check_suspend_result (MonoThreadInfo *info)
  46 {
  47         g_assert_not_reached ();
  48 }
  49
  50 gboolean
  51 mono_threads_suspend_begin_async_resume (MonoThreadInfo *info)
  52 {
  53         g_assert_not_reached ();
  54 }
  55
  56 void
  57 mono_threads_suspend_abort_syscall (MonoThreadInfo *info)
  58 {
  59 }
  60
  61 #else /* defined(HOST_WATCHOS) */
  62
  63 gboolean
  64 mono_threads_suspend_begin_async_suspend (MonoThreadInfo *info, gboolean interrupt_kernel)
  65 {
  66         kern_return_t ret;
  67
  68         g_assert (info);
  69
  70
  71         do {
  72                 ret = thread_suspend (info->native_handle);
  73         } while (ret == KERN_ABORTED);
  74
  75         THREADS_SUSPEND_DEBUG ("SUSPEND %p -> %d\n", (gpointer)(gsize)info->native_handle, ret);
  76         if (ret != KERN_SUCCESS)
  77                 return FALSE;
  78
  79         if (!mono_threads_transition_finish_async_suspend (info)) {
  80                 /* We raced with self-suspend and lost.  Resume the native
  81                  * thread.  It is still self-suspended, waiting to be resumed.
  82                  * So suspend can continue.
  83                  */
  84                 do {
  85                         ret = thread_resume (info->native_handle);
  86                 } while (ret == KERN_ABORTED);
  87                 g_assert (ret == KERN_SUCCESS);
  88                 info->suspend_can_continue = TRUE;
  89                 THREADS_SUSPEND_DEBUG ("\tlost race with self suspend %p\n", (gpointer)(gsize)info->native_handle);
  90                 g_assert (mono_threads_is_hybrid_suspension_enabled ());
  91                 //XXX interrupt_kernel doesn't make sense in this case as the target is not in a syscall
  92                 return TRUE;
  93         }
  94         info->suspend_can_continue = mono_threads_get_runtime_callbacks ()->
  95                 thread_state_init_from_handle (&info->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX], info, NULL);
  96         THREADS_SUSPEND_DEBUG ("thread state %p -> %d\n", (gpointer)(gsize)info->native_handle, ret);
  97         if (info->suspend_can_continue) {
  98                 if (interrupt_kernel)
  99                         thread_abort (info->native_handle);
 100         } else {
 101                 THREADS_SUSPEND_DEBUG ("FAILSAFE RESUME/2 %p -> %d\n", (gpointer)(gsize)info->native_handle, 0);
 102         }
 103         return TRUE;
 104 }
 105
 106 gboolean
 107 mono_threads_suspend_check_suspend_result (MonoThreadInfo *info)
 108 {
 109         return info->suspend_can_continue;
 110 }
 111
 112 gboolean
 113 mono_threads_suspend_begin_async_resume (MonoThreadInfo *info)
 114 {
 115         kern_return_t ret;
 116
 117         if (info->async_target) {
 118                 MonoContext tmp = info->thread_saved_state [ASYNC_SUSPEND_STATE_INDEX].ctx;
 119                 mach_msg_type_number_t num_state, num_fpstate;
 120                 thread_state_t state, fpstate;
 121                 ucontext_t uctx;
 122                 mcontext_t mctx;
 123
 124                 mono_threads_get_runtime_callbacks ()->setup_async_callback (&tmp, info->async_target, info->user_data);
 125                 info->user_data = NULL;
 126                 info->async_target = (void (*)(void *)) info->user_data;
 127
 128                 state = (thread_state_t) alloca (mono_mach_arch_get_thread_state_size ());
 129                 fpstate = (thread_state_t) alloca (mono_mach_arch_get_thread_fpstate_size ());
 130                 mctx = (mcontext_t) alloca (mono_mach_arch_get_mcontext_size ());
 131
 132                 do {
 133                         ret = mono_mach_arch_get_thread_states (info->native_handle, state, &num_state, fpstate, &num_fpstate);
 134                 } while (ret == KERN_ABORTED);
 135
 136                 if (ret != KERN_SUCCESS)
 137                         return FALSE;
 138
 139                 mono_mach_arch_thread_states_to_mcontext (state, fpstate, mctx);
 140                 uctx.uc_mcontext = mctx;
 141                 mono_monoctx_to_sigctx (&tmp, &uctx);
 142
 143                 mono_mach_arch_mcontext_to_thread_states (mctx, state, fpstate);
 144
 145                 do {
 146                         ret = mono_mach_arch_set_thread_states (info->native_handle, state, num_state, fpstate, num_fpstate);
 147                 } while (ret == KERN_ABORTED);
 148
 149                 if (ret != KERN_SUCCESS)
 150                         return FALSE;
 151         }
 152
 153         do {
 154                 ret = thread_resume (info->native_handle);
 155         } while (ret == KERN_ABORTED);
 156         THREADS_SUSPEND_DEBUG ("RESUME %p -> %d\n", (gpointer)(gsize)info->native_handle, ret);
 157
 158         return ret == KERN_SUCCESS;
 159 }
 160
 161 void
 162 mono_threads_suspend_abort_syscall (MonoThreadInfo *info)
 163 {
 164         kern_return_t ret;
 165
 166         do {
 167                 ret = thread_suspend (info->native_handle);
 168         } while (ret == KERN_ABORTED);
 169
 170         if (ret != KERN_SUCCESS)
 171                 return;
 172
 173         do {
 174                 ret = thread_abort_safely (info->native_handle);
 175         } while (ret == KERN_ABORTED);
 176
 177         /*
 178          * We are doing thread_abort when thread_abort_safely returns KERN_SUCCESS because
 179          * for some reason accept is not interrupted by thread_abort_safely.
 180          * The risk of aborting non-atomic operations while calling thread_abort should not
 181          * exist because by the time thread_abort_safely returns KERN_SUCCESS the target
 182          * thread should have return from the kernel and should be waiting for thread_resume
 183          * to resume the user code.
 184          */
 185         if (ret == KERN_SUCCESS)
 186                 ret = thread_abort (info->native_handle);
 187
 188         do {
 189                 ret = thread_resume (info->native_handle);
 190         } while (ret == KERN_ABORTED);
 191
 192         g_assert (ret == KERN_SUCCESS);
 193 }
 194
 195 #endif /* defined(HOST_WATCHOS) */
 196
 197 void
 198 mono_threads_suspend_register (MonoThreadInfo *info)
 199 {
 200         char thread_name [64];
 201
 202         info->native_handle = mach_thread_self ();
 203
 204         snprintf (thread_name, sizeof (thread_name), "tid_%x", (int) info->native_handle);
 205         pthread_setname_np (thread_name);
 206
 207         mono_threads_install_dead_letter ();
 208 }
 209
 210 void
 211 mono_threads_suspend_free (MonoThreadInfo *info)
 212 {
 213         mach_port_deallocate (current_task (), info->native_handle);
 214 }
 215
 216 void
 217 mono_threads_suspend_init_signals (void)
 218 {
 219 }
 220
 221 gint
 222 mono_threads_suspend_search_alternative_signal (void)
 223 {
 224         g_assert_not_reached ();
 225 }
 226
 227 gint
 228 mono_threads_suspend_get_suspend_signal (void)
 229 {
 230         return -1;
 231 }
 232
 233 gint
 234 mono_threads_suspend_get_restart_signal (void)
 235 {
 236         return -1;
 237 }
 238
 239 gint
 240 mono_threads_suspend_get_abort_signal (void)
 241 {
 242         return -1;
 243 }
 244
 245 #endif /* USE_MACH_BACKEND */
 246
 247 #ifdef __MACH__
 248 void
 249 mono_threads_platform_get_stack_bounds (guint8 **staddr, size_t *stsize)
 250 {
 251         *staddr = (guint8*)pthread_get_stackaddr_np (pthread_self());
 252         *stsize = pthread_get_stacksize_np (pthread_self());
 253
 254 #ifdef TARGET_OSX
 255         /*
 256          * Mavericks reports stack sizes as 512kb:
 257          * http://permalink.gmane.org/gmane.comp.java.openjdk.hotspot.devel/11590
 258          * https://bugs.openjdk.java.net/browse/JDK-8020753
 259          */
 260         if (pthread_main_np () && *stsize == 512 * 1024)
 261                 *stsize = 2048 * mono_pagesize ();
 262 #endif
 263
 264         /* staddr points to the start of the stack, not the end */
 265         *staddr -= *stsize;
 266 }
 267
 268 gboolean
 269 mono_threads_platform_is_main_thread (void)
 270 {
 271         return pthread_main_np () == 1;
 272 }
 273 #endif