2 * mini-posix.c: POSIX signal handling support for Mono.
5 * Mono Team (mono-list@lists.ximian.com)
7 * Copyright 2001-2003 Ximian, Inc.
8 * Copyright 2003-2008 Ximian, Inc.
10 * See LICENSE for licensing information.
21 #ifdef HAVE_SYS_TIME_H
24 #ifdef HAVE_SYS_SYSCALL_H
25 #include <sys/syscall.h>
28 #include <mono/metadata/assembly.h>
29 #include <mono/metadata/loader.h>
30 #include <mono/metadata/tabledefs.h>
31 #include <mono/metadata/class.h>
32 #include <mono/metadata/object.h>
33 #include <mono/metadata/tokentype.h>
34 #include <mono/metadata/tabledefs.h>
35 #include <mono/metadata/threads.h>
36 #include <mono/metadata/appdomain.h>
37 #include <mono/metadata/debug-helpers.h>
38 #include <mono/io-layer/io-layer.h>
39 #include "mono/metadata/profiler.h"
40 #include <mono/metadata/profiler-private.h>
41 #include <mono/metadata/mono-config.h>
42 #include <mono/metadata/environment.h>
43 #include <mono/metadata/mono-debug.h>
44 #include <mono/metadata/gc-internal.h>
45 #include <mono/metadata/threads-types.h>
46 #include <mono/metadata/verify.h>
47 #include <mono/metadata/verify-internals.h>
48 #include <mono/metadata/mempool-internals.h>
49 #include <mono/metadata/attach.h>
50 #include <mono/utils/mono-math.h>
51 #include <mono/utils/mono-compiler.h>
52 #include <mono/utils/mono-counters.h>
53 #include <mono/utils/mono-logger-internal.h>
54 #include <mono/utils/mono-mmap.h>
55 #include <mono/utils/dtrace.h>
62 #include "debugger-agent.h"
64 #include "jit-icalls.h"
66 #if defined(__native_client__)
69 mono_runtime_setup_stat_profiler (void)
71 printf("WARNING: mono_runtime_setup_stat_profiler() called!\n");
76 mono_runtime_shutdown_stat_profiler (void)
82 SIG_HANDLER_SIGNATURE (mono_chain_signal
)
88 mono_runtime_install_handlers (void)
93 mono_runtime_shutdown_handlers (void)
98 mono_runtime_cleanup_handlers (void)
106 static GHashTable
*mono_saved_signal_handlers
= NULL
;
109 get_saved_signal_handler (int signo
)
111 if (mono_saved_signal_handlers
)
112 /* The hash is only modified during startup, so no need for locking */
113 return g_hash_table_lookup (mono_saved_signal_handlers
, GINT_TO_POINTER (signo
));
118 save_old_signal_handler (int signo
, struct sigaction
*old_action
)
120 struct sigaction
*handler_to_save
= g_malloc (sizeof (struct sigaction
));
122 mono_trace (G_LOG_LEVEL_DEBUG
, MONO_TRACE_CONFIG
,
123 "Saving old signal handler for signal %d.", signo
);
125 if (! (old_action
->sa_flags
& SA_SIGINFO
)) {
126 handler_to_save
->sa_handler
= old_action
->sa_handler
;
128 #ifdef MONO_ARCH_USE_SIGACTION
129 handler_to_save
->sa_sigaction
= old_action
->sa_sigaction
;
130 #endif /* MONO_ARCH_USE_SIGACTION */
132 handler_to_save
->sa_mask
= old_action
->sa_mask
;
133 handler_to_save
->sa_flags
= old_action
->sa_flags
;
135 if (!mono_saved_signal_handlers
)
136 mono_saved_signal_handlers
= g_hash_table_new (NULL
, NULL
);
137 g_hash_table_insert (mono_saved_signal_handlers
, GINT_TO_POINTER (signo
), handler_to_save
);
141 free_saved_sig_handler_func (gpointer key
, gpointer value
, gpointer user_data
)
147 free_saved_signal_handlers (void)
149 if (mono_saved_signal_handlers
) {
150 g_hash_table_foreach (mono_saved_signal_handlers
, free_saved_sig_handler_func
, NULL
);
151 g_hash_table_destroy (mono_saved_signal_handlers
);
152 mono_saved_signal_handlers
= NULL
;
159 * Call the original signal handler for the signal given by the arguments, which
160 * should be the same as for a signal handler. Returns TRUE if the original handler
161 * was called, false otherwise.
164 SIG_HANDLER_SIGNATURE (mono_chain_signal
)
167 struct sigaction
*saved_handler
= get_saved_signal_handler (signal
);
172 if (!(saved_handler
->sa_flags
& SA_SIGINFO
)) {
173 saved_handler
->sa_handler (signal
);
175 #ifdef MONO_ARCH_USE_SIGACTION
176 saved_handler
->sa_sigaction (signal
, info
, ctx
);
177 #endif /* MONO_ARCH_USE_SIGACTION */
185 SIG_HANDLER_SIGNATURE (sigabrt_signal_handler
)
187 MonoJitInfo
*ji
= NULL
;
190 if (mono_thread_internal_current ())
191 ji
= mono_jit_info_table_find (mono_domain_get (), mono_arch_ip_from_context(ctx
));
193 if (mono_chain_signal (SIG_HANDLER_PARAMS
))
195 mono_handle_native_sigsegv (SIGABRT
, ctx
);
200 SIG_HANDLER_SIGNATURE (sigusr1_signal_handler
)
203 gboolean running_managed
;
205 MonoInternalThread
*thread
= mono_thread_internal_current ();
206 MonoDomain
*domain
= mono_domain_get ();
211 if (!thread
|| !domain
)
212 /* The thread might not have started up yet */
213 /* FIXME: Specify the synchronization with start_wrapper () in threads.c */
216 if (thread
->thread_dump_requested
) {
217 thread
->thread_dump_requested
= FALSE
;
219 mono_print_thread_dump (ctx
);
223 * This is an async signal, so the code below must not call anything which
224 * is not async safe. That includes the pthread locking functions. If we
225 * know that we interrupted managed code, then locking is safe.
228 * On OpenBSD, ctx can be NULL if we are interrupting poll ().
231 ji
= mono_jit_info_table_find (mono_domain_get (), mono_arch_ip_from_context(ctx
));
232 running_managed
= ji
!= NULL
;
234 if (mono_debugger_agent_thread_interrupt (ctx
, ji
))
237 running_managed
= FALSE
;
240 /* We can't do handler block checking from metadata since it requires doing
241 * a stack walk with context.
243 * FIXME add full-aot support.
245 #ifdef MONO_ARCH_HAVE_SIGCTX_TO_MONOCTX
246 if (!mono_aot_only
&& ctx
) {
247 mono_arch_sigctx_to_monoctx (ctx
, &mctx
);
248 if (mono_install_handler_block_guard (thread
, &mctx
)) {
254 exc
= mono_thread_request_interruption (running_managed
);
258 mono_arch_handle_exception (ctx
, exc
, FALSE
);
261 #if defined(__i386__) || defined(__x86_64__)
262 #define FULL_STAT_PROFILER_BACKTRACE 1
263 #define CURRENT_FRAME_GET_BASE_POINTER(f) (* (gpointer*)(f))
264 #define CURRENT_FRAME_GET_RETURN_ADDRESS(f) (* (((gpointer*)(f)) + 1))
265 #if MONO_ARCH_STACK_GROWS_UP
266 #define IS_BEFORE_ON_STACK <
267 #define IS_AFTER_ON_STACK >
269 #define IS_BEFORE_ON_STACK >
270 #define IS_AFTER_ON_STACK <
273 #define FULL_STAT_PROFILER_BACKTRACE 0
276 #if defined(__ia64__) || defined(__sparc__) || defined(sparc) || defined(__s390__) || defined(s390)
279 SIG_HANDLER_SIGNATURE (sigprof_signal_handler
)
281 if (mono_chain_signal (SIG_HANDLER_PARAMS
))
290 SIG_HANDLER_SIGNATURE (sigprof_signal_handler
)
292 int call_chain_depth
= mono_profiler_stat_get_call_chain_depth ();
293 MonoProfilerCallChainStrategy call_chain_strategy
= mono_profiler_stat_get_call_chain_strategy ();
296 if (call_chain_depth
== 0) {
297 mono_profiler_stat_hit (mono_arch_ip_from_context (ctx
), ctx
);
299 MonoJitTlsData
*jit_tls
= TlsGetValue (mono_jit_tls_id
);
300 int current_frame_index
= 1;
301 MonoContext mono_context
;
302 guchar
*ips
[call_chain_depth
+ 1];
304 mono_arch_sigctx_to_monoctx (ctx
, &mono_context
);
305 ips
[0] = MONO_CONTEXT_GET_IP (&mono_context
);
307 if (jit_tls
!= NULL
) {
308 if (call_chain_strategy
== MONO_PROFILER_CALL_CHAIN_NATIVE
) {
309 #if FULL_STAT_PROFILER_BACKTRACE
310 guchar
*current_frame
;
311 guchar
*stack_bottom
;
314 stack_bottom
= jit_tls
->end_of_stack
;
315 stack_top
= MONO_CONTEXT_GET_SP (&mono_context
);
316 current_frame
= MONO_CONTEXT_GET_BP (&mono_context
);
318 while ((current_frame_index
<= call_chain_depth
) &&
319 (stack_bottom
IS_BEFORE_ON_STACK (guchar
*) current_frame
) &&
320 ((guchar
*) current_frame IS_BEFORE_ON_STACK stack_top
)) {
321 ips
[current_frame_index
] = CURRENT_FRAME_GET_RETURN_ADDRESS (current_frame
);
322 current_frame_index
++;
323 stack_top
= current_frame
;
324 current_frame
= CURRENT_FRAME_GET_BASE_POINTER (current_frame
);
327 call_chain_strategy
= MONO_PROFILER_CALL_CHAIN_GLIBC
;
331 if (call_chain_strategy
== MONO_PROFILER_CALL_CHAIN_GLIBC
) {
332 #if GLIBC_PROFILER_BACKTRACE
333 current_frame_index
= backtrace ((void**) & ips
[1], call_chain_depth
);
335 call_chain_strategy
= MONO_PROFILER_CALL_CHAIN_MANAGED
;
339 if (call_chain_strategy
== MONO_PROFILER_CALL_CHAIN_MANAGED
) {
340 MonoDomain
*domain
= mono_domain_get ();
341 if (domain
!= NULL
) {
345 MonoContext new_mono_context
;
347 ji
= mono_find_jit_info (domain
, jit_tls
, &res
, NULL
, &mono_context
,
348 &new_mono_context
, NULL
, &lmf
, &native_offset
, NULL
);
349 while ((ji
!= NULL
) && (current_frame_index
<= call_chain_depth
)) {
350 ips
[current_frame_index
] = MONO_CONTEXT_GET_IP (&new_mono_context
);
351 current_frame_index
++;
352 mono_context
= new_mono_context
;
353 ji
= mono_find_jit_info (domain
, jit_tls
, &res
, NULL
, &mono_context
,
354 &new_mono_context
, NULL
, &lmf
, &native_offset
, NULL
);
360 mono_profiler_stat_call_chain (current_frame_index
, & ips
[0], ctx
);
363 mono_chain_signal (SIG_HANDLER_PARAMS
);
369 SIG_HANDLER_SIGNATURE (sigquit_signal_handler
)
375 /* We use this signal to start the attach agent too */
376 res
= mono_attach_start ();
380 printf ("Full thread dump:\n");
382 mono_threads_request_thread_dump ();
385 * print_thread_dump () skips the current thread, since sending a signal
386 * to it would invoke the signal handler below the sigquit signal handler,
387 * and signal handlers don't create an lmf, so the stack walk could not
390 mono_print_thread_dump (ctx
);
392 mono_chain_signal (SIG_HANDLER_PARAMS
);
396 SIG_HANDLER_SIGNATURE (sigusr2_signal_handler
)
398 gboolean enabled
= mono_trace_is_enabled ();
400 mono_trace_enable (!enabled
);
402 mono_chain_signal (SIG_HANDLER_PARAMS
);
406 add_signal_handler (int signo
, gpointer handler
)
409 struct sigaction previous_sa
;
411 #ifdef MONO_ARCH_USE_SIGACTION
412 sa
.sa_sigaction
= handler
;
413 sigemptyset (&sa
.sa_mask
);
414 sa
.sa_flags
= SA_SIGINFO
;
415 #ifdef MONO_ARCH_SIGSEGV_ON_ALTSTACK
416 if (signo
== SIGSEGV
) {
417 sa
.sa_flags
|= SA_ONSTACK
;
420 * libgc will crash when trying to do stack marking for threads which are on
421 * an altstack, so delay the suspend signal after the signal handler has
424 if (mono_gc_get_suspend_signal () != -1)
425 sigaddset (&sa
.sa_mask
, mono_gc_get_suspend_signal ());
428 if (signo
== SIGSEGV
) {
430 * Delay abort signals while handling SIGSEGVs since they could go unnoticed.
434 sigemptyset (&block_mask
);
435 sigaddset (&sa
.sa_mask
, mono_thread_get_abort_signal ());
438 sa
.sa_handler
= handler
;
439 sigemptyset (&sa
.sa_mask
);
442 g_assert (sigaction (signo
, &sa
, &previous_sa
) != -1);
444 /* if there was already a handler in place for this signal, store it */
445 if (! (previous_sa
.sa_flags
& SA_SIGINFO
) &&
446 (SIG_DFL
== previous_sa
.sa_handler
)) {
447 /* it there is no sa_sigaction function and the sa_handler is default, we can safely ignore this */
449 if (mono_do_signal_chaining
)
450 save_old_signal_handler (signo
, &previous_sa
);
455 remove_signal_handler (int signo
)
458 struct sigaction
*saved_action
= get_saved_signal_handler (signo
);
461 sa
.sa_handler
= SIG_DFL
;
462 sigemptyset (&sa
.sa_mask
);
465 sigaction (signo
, &sa
, NULL
);
467 g_assert (sigaction (signo
, saved_action
, NULL
) != -1);
472 mono_runtime_posix_install_handlers (void)
477 if (mini_get_debug_options ()->handle_sigint
)
478 add_signal_handler (SIGINT
, mono_sigint_signal_handler
);
480 add_signal_handler (SIGFPE
, mono_sigfpe_signal_handler
);
481 add_signal_handler (SIGQUIT
, sigquit_signal_handler
);
482 add_signal_handler (SIGILL
, mono_sigill_signal_handler
);
483 add_signal_handler (SIGBUS
, mono_sigsegv_signal_handler
);
484 if (mono_jit_trace_calls
!= NULL
)
485 add_signal_handler (SIGUSR2
, sigusr2_signal_handler
);
487 add_signal_handler (mono_thread_get_abort_signal (), sigusr1_signal_handler
);
488 /* it seems to have become a common bug for some programs that run as parents
489 * of many processes to block signal delivery for real time signals.
490 * We try to detect and work around their breakage here.
492 sigemptyset (&signal_set
);
493 sigaddset (&signal_set
, mono_thread_get_abort_signal ());
494 sigprocmask (SIG_UNBLOCK
, &signal_set
, NULL
);
496 signal (SIGPIPE
, SIG_IGN
);
498 add_signal_handler (SIGABRT
, sigabrt_signal_handler
);
501 add_signal_handler (SIGSEGV
, mono_sigsegv_signal_handler
);
504 #ifndef PLATFORM_MACOSX
506 mono_runtime_install_handlers (void)
508 mono_runtime_posix_install_handlers ();
513 mono_runtime_cleanup_handlers (void)
515 if (mini_get_debug_options ()->handle_sigint
)
516 remove_signal_handler (SIGINT
);
518 remove_signal_handler (SIGFPE
);
519 remove_signal_handler (SIGQUIT
);
520 remove_signal_handler (SIGILL
);
521 remove_signal_handler (SIGBUS
);
522 if (mono_jit_trace_calls
!= NULL
)
523 remove_signal_handler (SIGUSR2
);
525 remove_signal_handler (mono_thread_get_abort_signal ());
527 remove_signal_handler (SIGABRT
);
529 remove_signal_handler (SIGSEGV
);
531 free_saved_signal_handlers ();
534 #ifdef HAVE_LINUX_RTC_H
535 #include <linux/rtc.h>
536 #include <sys/ioctl.h>
538 static int rtc_fd
= -1;
541 enable_rtc_timer (gboolean enable
)
544 flags
= fcntl (rtc_fd
, F_GETFL
);
553 if (fcntl (rtc_fd
, F_SETFL
, flags
) == -1) {
562 mono_runtime_shutdown_stat_profiler (void)
564 #ifdef HAVE_LINUX_RTC_H
566 enable_rtc_timer (FALSE
);
571 mono_runtime_setup_stat_profiler (void)
574 struct itimerval itval
;
575 static int inited
= 0;
576 #ifdef HAVE_LINUX_RTC_H
577 const char *rtc_freq
;
578 if (!inited
&& (rtc_freq
= g_getenv ("MONO_RTC"))) {
582 freq
= atoi (rtc_freq
);
585 rtc_fd
= open ("/dev/rtc", O_RDONLY
);
587 perror ("open /dev/rtc");
590 add_signal_handler (SIGPROF
, sigprof_signal_handler
);
591 if (ioctl (rtc_fd
, RTC_IRQP_SET
, freq
) == -1) {
592 perror ("set rtc freq");
595 if (ioctl (rtc_fd
, RTC_PIE_ON
, 0) == -1) {
596 perror ("start rtc");
599 if (fcntl (rtc_fd
, F_SETSIG
, SIGPROF
) == -1) {
603 if (fcntl (rtc_fd
, F_SETOWN
, getpid ()) == -1) {
607 enable_rtc_timer (TRUE
);
614 itval
.it_interval
.tv_usec
= 999;
615 itval
.it_interval
.tv_sec
= 0;
616 itval
.it_value
= itval
.it_interval
;
617 setitimer (ITIMER_PROF
, &itval
, NULL
);
621 add_signal_handler (SIGPROF
, sigprof_signal_handler
);
625 #if !defined(__APPLE__)
627 mono_runtime_syscall_fork ()
629 #if defined(SYS_fork)
630 return (pid_t
) syscall (SYS_fork
);
632 g_assert_not_reached ();
638 mono_gdb_render_native_backtraces ()
640 const char *argv
[9];
643 argv
[0] = g_find_program_in_path ("gdb");
644 if (argv
[0] == NULL
) {
649 sprintf (buf1
, "attach %ld", (long)getpid ());
652 argv
[4] = "info threads";
654 argv
[6] = "thread apply all bt";
655 argv
[7] = "--batch";
658 execv (argv
[0], (char**)argv
);
663 #endif /* __native_client__ */