-/*
- * mini-posix.c: POSIX signal handling support for Mono.
+/**
+ * \file
+ * POSIX signal handling support for Mono.
*
* Authors:
* Mono Team (mono-list@lists.ximian.com)
* Copyright 2011 Xamarin, Inc (http://www.xamarin.com)
*
* See LICENSE for licensing information.
+ * Licensed under the MIT license. See LICENSE file in the project root for full license information.
*/
#include <config.h>
#include <signal.h>
#include <sys/syscall.h>
#endif
#include <errno.h>
-
+#include <sched.h>
#include <mono/metadata/assembly.h>
#include <mono/metadata/loader.h>
#include <mono/metadata/threads.h>
#include <mono/metadata/appdomain.h>
#include <mono/metadata/debug-helpers.h>
-#include <mono/io-layer/io-layer.h>
-#include "mono/metadata/profiler.h"
#include <mono/metadata/profiler-private.h>
#include <mono/metadata/mono-config.h>
#include <mono/metadata/environment.h>
#include "jit-icalls.h"
-#if defined(__native_client__) || defined(HOST_WATCHOS)
+#ifdef HOST_DARWIN
+#include <mach/mach.h>
+#include <mach/mach_time.h>
+#include <mach/clock.h>
+#endif
+
+#if defined(HOST_WATCHOS)
void
mono_runtime_setup_stat_profiler (void)
return FALSE;
}
-#ifndef PLATFORM_MACOSX
+#ifndef HOST_DARWIN
void
mono_runtime_install_handlers (void)
{
void
mono_runtime_posix_install_handlers(void)
{
-
+ /* we still need to ignore SIGPIPE */
+ signal (SIGPIPE, SIG_IGN);
}
void
{
}
-#if !defined(PLATFORM_MACOSX)
-pid_t
-mono_runtime_syscall_fork (void)
-{
- g_assert_not_reached();
- return 0;
-}
-
-void
-mono_gdb_render_native_backtraces (pid_t crashed_pid)
-{
-}
-#endif
-
#else
static GHashTable *mono_saved_signal_handlers = NULL;
static struct sigaction *
-get_saved_signal_handler (int signo)
+get_saved_signal_handler (int signo, gboolean remove)
{
- if (mono_saved_signal_handlers)
+ if (mono_saved_signal_handlers) {
/* The hash is only modified during startup, so no need for locking */
- return (struct sigaction *)g_hash_table_lookup (mono_saved_signal_handlers, GINT_TO_POINTER (signo));
+ struct sigaction *handler = g_hash_table_lookup (mono_saved_signal_handlers, GINT_TO_POINTER (signo));
+ if (remove && handler)
+ g_hash_table_remove (mono_saved_signal_handlers, GINT_TO_POINTER (signo));
+ return handler;
+ }
return NULL;
}
handler_to_save->sa_flags = old_action->sa_flags;
if (!mono_saved_signal_handlers)
- mono_saved_signal_handlers = g_hash_table_new (NULL, NULL);
+ mono_saved_signal_handlers = g_hash_table_new_full (NULL, NULL, NULL, g_free);
g_hash_table_insert (mono_saved_signal_handlers, GINT_TO_POINTER (signo), handler_to_save);
}
-static void
-free_saved_sig_handler_func (gpointer key, gpointer value, gpointer user_data)
-{
- g_free (value);
-}
-
static void
free_saved_signal_handlers (void)
{
if (mono_saved_signal_handlers) {
- g_hash_table_foreach (mono_saved_signal_handlers, free_saved_sig_handler_func, NULL);
g_hash_table_destroy (mono_saved_signal_handlers);
mono_saved_signal_handlers = NULL;
}
MONO_SIG_HANDLER_SIGNATURE (mono_chain_signal)
{
int signal = MONO_SIG_HANDLER_GET_SIGNO ();
- struct sigaction *saved_handler = (struct sigaction *)get_saved_signal_handler (signal);
+ struct sigaction *saved_handler = (struct sigaction *)get_saved_signal_handler (signal, FALSE);
if (saved_handler && saved_handler->sa_handler) {
if (!(saved_handler->sa_flags & SA_SIGINFO)) {
if (!ji) {
if (mono_chain_signal (MONO_SIG_HANDLER_PARAMS))
return;
- mono_handle_native_sigsegv (SIGABRT, ctx, info);
+ mono_handle_native_crash ("SIGABRT", ctx, info);
}
}
-#if defined(__i386__) || defined(__x86_64__)
-#define FULL_STAT_PROFILER_BACKTRACE 1
-#define CURRENT_FRAME_GET_BASE_POINTER(f) (* (gpointer*)(f))
-#define CURRENT_FRAME_GET_RETURN_ADDRESS(f) (* (((gpointer*)(f)) + 1))
-#if MONO_ARCH_STACK_GROWS_UP
-#define IS_BEFORE_ON_STACK <
-#define IS_AFTER_ON_STACK >
-#else
-#define IS_BEFORE_ON_STACK >
-#define IS_AFTER_ON_STACK <
-#endif
-#else
-#define FULL_STAT_PROFILER_BACKTRACE 0
+#if (defined (USE_POSIX_BACKEND) && defined (SIGRTMIN)) || defined (SIGPROF)
+#define HAVE_PROFILER_SIGNAL
#endif
-#ifdef SIGPROF
+#ifdef HAVE_PROFILER_SIGNAL
-static int profiling_signal_in_use;
+static MonoNativeThreadId sampling_thread;
-#if defined(__ia64__) || defined(__sparc__) || defined(sparc)
+static gint32 profiler_signals_sent;
+static gint32 profiler_signals_received;
+static gint32 profiler_signals_accepted;
+static gint32 profiler_interrupt_signals_received;
-MONO_SIG_HANDLER_FUNC (static, sigprof_signal_handler)
+MONO_SIG_HANDLER_FUNC (static, profiler_signal_handler)
{
- if (mono_chain_signal (MONO_SIG_HANDLER_PARAMS))
- return;
+ int old_errno = errno;
- NOT_IMPLEMENTED;
-}
+ MONO_SIG_HANDLER_GET_CONTEXT;
-#else
+ /* See the comment in mono_runtime_shutdown_stat_profiler (). */
+ if (mono_native_thread_id_get () == sampling_thread) {
+ InterlockedIncrement (&profiler_interrupt_signals_received);
+ return;
+ }
-static void
-per_thread_profiler_hit (void *ctx)
-{
- int call_chain_depth = mono_profiler_stat_get_call_chain_depth ();
- MonoProfilerCallChainStrategy call_chain_strategy = mono_profiler_stat_get_call_chain_strategy ();
+ InterlockedIncrement (&profiler_signals_received);
- if (call_chain_depth == 0) {
- mono_profiler_stat_hit ((guchar *)mono_arch_ip_from_context (ctx), ctx);
- } else {
- MonoJitTlsData *jit_tls = (MonoJitTlsData *)mono_native_tls_get_value (mono_jit_tls_id);
- int current_frame_index = 1;
- MonoContext mono_context;
- guchar *ips [call_chain_depth + 1];
-
- mono_sigctx_to_monoctx (ctx, &mono_context);
- ips [0] = (guchar *)MONO_CONTEXT_GET_IP (&mono_context);
-
- if (jit_tls != NULL) {
- if (call_chain_strategy == MONO_PROFILER_CALL_CHAIN_NATIVE) {
-#if FULL_STAT_PROFILER_BACKTRACE
- guchar *current_frame;
- guchar *stack_bottom;
- guchar *stack_top;
-
- stack_bottom = (guchar *)jit_tls->end_of_stack;
- stack_top = (guchar *)MONO_CONTEXT_GET_SP (&mono_context);
- current_frame = (guchar *)MONO_CONTEXT_GET_BP (&mono_context);
-
- while ((current_frame_index <= call_chain_depth) &&
- (stack_bottom IS_BEFORE_ON_STACK (guchar*) current_frame) &&
- ((guchar*) current_frame IS_BEFORE_ON_STACK stack_top)) {
- ips [current_frame_index] = (guchar *)CURRENT_FRAME_GET_RETURN_ADDRESS (current_frame);
- current_frame_index ++;
- stack_top = current_frame;
- current_frame = (guchar *)CURRENT_FRAME_GET_BASE_POINTER (current_frame);
- }
-#else
- call_chain_strategy = MONO_PROFILER_CALL_CHAIN_GLIBC;
-#endif
- }
-
- if (call_chain_strategy == MONO_PROFILER_CALL_CHAIN_GLIBC) {
-#if GLIBC_PROFILER_BACKTRACE
- current_frame_index = backtrace ((void**) & ips [1], call_chain_depth);
-#else
- call_chain_strategy = MONO_PROFILER_CALL_CHAIN_MANAGED;
-#endif
- }
-
- if (call_chain_strategy == MONO_PROFILER_CALL_CHAIN_MANAGED) {
- MonoDomain *domain = mono_domain_get ();
- if (domain != NULL) {
- MonoLMF *lmf = NULL;
- MonoJitInfo *ji;
- MonoJitInfo res;
- MonoContext new_mono_context;
- int native_offset;
- ji = mono_find_jit_info (domain, jit_tls, &res, NULL, &mono_context,
- &new_mono_context, NULL, &lmf, &native_offset, NULL);
- while ((ji != NULL) && (current_frame_index <= call_chain_depth)) {
- ips [current_frame_index] = (guchar *)MONO_CONTEXT_GET_IP (&new_mono_context);
- current_frame_index ++;
- mono_context = new_mono_context;
- ji = mono_find_jit_info (domain, jit_tls, &res, NULL, &mono_context,
- &new_mono_context, NULL, &lmf, &native_offset, NULL);
- }
- }
- }
- }
-
- mono_profiler_stat_call_chain (current_frame_index, & ips [0], ctx);
+ // Did a non-attached or detaching thread get the signal?
+ if (mono_thread_info_get_small_id () == -1 ||
+ !mono_domain_get () ||
+ !mono_tls_get_jit_tls ()) {
+ errno = old_errno;
+ return;
}
-}
-
-MONO_SIG_HANDLER_FUNC (static, sigprof_signal_handler)
-{
- int old_errno = errno;
- int hp_save_index;
- MONO_SIG_HANDLER_GET_CONTEXT;
- if (mono_thread_info_get_small_id () == -1)
- return; //an non-attached thread got the signal
+ // See the comment in sampling_thread_func ().
+ InterlockedWrite (&mono_thread_info_current ()->profiler_signal_ack, 1);
- if (!mono_domain_get () || !mono_native_tls_get_value (mono_jit_tls_id))
- return; //thread in the process of dettaching
+ InterlockedIncrement (&profiler_signals_accepted);
- hp_save_index = mono_hazard_pointer_save_for_signal_handler ();
+ int hp_save_index = mono_hazard_pointer_save_for_signal_handler ();
- /* If we can't consume a profiling request it means we're the initiator. */
- if (!(mono_threads_consume_async_jobs () & MONO_SERVICE_REQUEST_SAMPLE)) {
- FOREACH_THREAD_SAFE (info) {
- if (mono_thread_info_get_tid (info) == mono_native_thread_id_get () ||
- !mono_thread_info_is_live (info))
- continue;
+ mono_thread_info_set_is_async_context (TRUE);
- mono_threads_add_async_job (info, MONO_SERVICE_REQUEST_SAMPLE);
- mono_threads_pthread_kill (info, profiling_signal_in_use);
- } FOREACH_THREAD_SAFE_END
- }
+ MONO_PROFILER_RAISE (sample_hit, (mono_arch_ip_from_context (ctx), ctx));
- mono_thread_info_set_is_async_context (TRUE);
- per_thread_profiler_hit (ctx);
mono_thread_info_set_is_async_context (FALSE);
mono_hazard_pointer_restore_for_signal_handler (hp_save_index);
+
errno = old_errno;
mono_chain_signal (MONO_SIG_HANDLER_PARAMS);
}
-#endif
#endif
MONO_SIG_HANDLER_FUNC (static, sigquit_signal_handler)
#ifdef MONO_ARCH_SIGSEGV_ON_ALTSTACK
/*Apple likes to deliver SIGBUS for *0 */
-#ifdef PLATFORM_MACOSX
+#ifdef HOST_DARWIN
if (signo == SIGSEGV || signo == SIGBUS) {
#else
if (signo == SIGSEGV) {
remove_signal_handler (int signo)
{
struct sigaction sa;
- struct sigaction *saved_action = get_saved_signal_handler (signo);
+ struct sigaction *saved_action = get_saved_signal_handler (signo, TRUE);
if (!saved_action) {
sa.sa_handler = SIG_DFL;
add_signal_handler (SIGSEGV, mono_sigsegv_signal_handler, 0);
}
-#ifndef PLATFORM_MACOSX
+#ifndef HOST_DARWIN
void
mono_runtime_install_handlers (void)
{
free_saved_signal_handlers ();
}
-#ifdef HAVE_LINUX_RTC_H
-#include <linux/rtc.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
-static int rtc_fd = -1;
+#ifdef HAVE_PROFILER_SIGNAL
+
+static volatile gint32 sampling_thread_running;
+
+#ifdef HOST_DARWIN
+
+static clock_serv_t sampling_clock_service;
+
+static void
+clock_init (MonoProfilerSampleMode mode)
+{
+ kern_return_t ret;
+
+ do {
+ ret = host_get_clock_service (mach_host_self (), SYSTEM_CLOCK, &sampling_clock_service);
+ } while (ret == KERN_ABORTED);
+
+ if (ret != KERN_SUCCESS)
+ g_error ("%s: host_get_clock_service () returned %d", __func__, ret);
+}
+
+static void
+clock_cleanup (void)
+{
+ kern_return_t ret;
+
+ do {
+ ret = mach_port_deallocate (mach_task_self (), sampling_clock_service);
+ } while (ret == KERN_ABORTED);
+
+ if (ret != KERN_SUCCESS)
+ g_error ("%s: mach_port_deallocate () returned %d", __func__, ret);
+}
+
+static guint64
+clock_get_time_ns (void)
+{
+ kern_return_t ret;
+ mach_timespec_t mach_ts;
+
+ do {
+ ret = clock_get_time (sampling_clock_service, &mach_ts);
+ } while (ret == KERN_ABORTED);
-static int
-enable_rtc_timer (gboolean enable)
+ if (ret != KERN_SUCCESS)
+ g_error ("%s: clock_get_time () returned %d", __func__, ret);
+
+ return ((guint64) mach_ts.tv_sec * 1000000000) + (guint64) mach_ts.tv_nsec;
+}
+
+static void
+clock_sleep_ns_abs (guint64 ns_abs)
{
- int flags;
- flags = fcntl (rtc_fd, F_GETFL);
- if (flags < 0) {
- perror ("getflags");
- return 0;
+ kern_return_t ret;
+ mach_timespec_t then, remain_unused;
+
+ then.tv_sec = ns_abs / 1000000000;
+ then.tv_nsec = ns_abs % 1000000000;
+
+ do {
+ ret = clock_sleep (sampling_clock_service, TIME_ABSOLUTE, then, &remain_unused);
+
+ if (ret != KERN_SUCCESS && ret != KERN_ABORTED)
+ g_error ("%s: clock_sleep () returned %d", __func__, ret);
+ } while (ret == KERN_ABORTED && InterlockedRead (&sampling_thread_running));
+}
+
+#else
+
+clockid_t sampling_posix_clock;
+
+static void
+clock_init (MonoProfilerSampleMode mode)
+{
+ switch (mode) {
+ case MONO_PROFILER_SAMPLE_MODE_PROCESS: {
+ /*
+ * If we don't have clock_nanosleep (), measuring the process time
+ * makes very little sense as we can only use nanosleep () to sleep on
+ * real time.
+ */
+#ifdef HAVE_CLOCK_NANOSLEEP
+ struct timespec ts = { 0 };
+
+ /*
+ * Some systems (e.g. Windows Subsystem for Linux) declare the
+ * CLOCK_PROCESS_CPUTIME_ID clock but don't actually support it. For
+ * those systems, we fall back to CLOCK_MONOTONIC if we get EINVAL.
+ */
+ if (clock_nanosleep (CLOCK_PROCESS_CPUTIME_ID, TIMER_ABSTIME, &ts, NULL) != EINVAL) {
+ sampling_posix_clock = CLOCK_PROCESS_CPUTIME_ID;
+ break;
+ }
+#endif
+
+ // fallthrough
}
- if (enable)
- flags |= FASYNC;
- else
- flags &= ~FASYNC;
- if (fcntl (rtc_fd, F_SETFL, flags) == -1) {
- perror ("setflags");
- return 0;
+ case MONO_PROFILER_SAMPLE_MODE_REAL: sampling_posix_clock = CLOCK_MONOTONIC; break;
+ default: g_assert_not_reached (); break;
}
- return 1;
}
-#endif
-void
-mono_runtime_shutdown_stat_profiler (void)
+static void
+clock_cleanup (void)
{
-#ifdef HAVE_LINUX_RTC_H
- if (rtc_fd >= 0)
- enable_rtc_timer (FALSE);
-#endif
}
-#ifdef ITIMER_PROF
-static int
-get_itimer_mode (void)
+static guint64
+clock_get_time_ns (void)
{
- switch (mono_profiler_get_sampling_mode ()) {
- case MONO_PROFILER_STAT_MODE_PROCESS: return ITIMER_PROF;
- case MONO_PROFILER_STAT_MODE_REAL: return ITIMER_REAL;
- }
- g_assert_not_reached ();
- return 0;
+ struct timespec ts;
+
+ if (clock_gettime (sampling_posix_clock, &ts) == -1)
+ g_error ("%s: clock_gettime () returned -1, errno = %d", __func__, errno);
+
+ return ((guint64) ts.tv_sec * 1000000000) + (guint64) ts.tv_nsec;
}
-static int
-get_itimer_signal (void)
+static void
+clock_sleep_ns_abs (guint64 ns_abs)
{
- switch (mono_profiler_get_sampling_mode ()) {
- case MONO_PROFILER_STAT_MODE_PROCESS: return SIGPROF;
- case MONO_PROFILER_STAT_MODE_REAL: return SIGALRM;
- }
- g_assert_not_reached ();
- return 0;
+#ifdef HAVE_CLOCK_NANOSLEEP
+ int ret;
+ struct timespec then;
+
+ then.tv_sec = ns_abs / 1000000000;
+ then.tv_nsec = ns_abs % 1000000000;
+
+ do {
+ ret = clock_nanosleep (sampling_posix_clock, TIMER_ABSTIME, &then, NULL);
+
+ if (ret != 0 && ret != EINTR)
+ g_error ("%s: clock_nanosleep () returned %d", __func__, ret);
+ } while (ret == EINTR && InterlockedRead (&sampling_thread_running));
+#else
+ int ret;
+ gint64 diff;
+ struct timespec req;
+
+ /*
+ * What follows is a crude attempt at emulating clock_nanosleep () on OSs
+ * which don't provide it (e.g. FreeBSD).
+ *
+ * The problem with nanosleep () is that if it is interrupted by a signal,
+ * time will drift as a result of having to restart the call after the
+ * signal handler has finished. For this reason, we avoid using the rem
+ * argument of nanosleep (). Instead, before every nanosleep () call, we
+ * check if enough time has passed to satisfy the sleep request. If yes, we
+ * simply return. If not, we calculate the difference and do another sleep.
+ *
+ * This should reduce the amount of drift that happens because we account
+ * for the time spent executing the signal handler, which nanosleep () is
+ * not guaranteed to do for the rem argument.
+ *
+ * The downside to this approach is that it is slightly expensive: We have
+ * to make an extra system call to retrieve the current time whenever we're
+ * going to restart a nanosleep () call. This is unlikely to be a problem
+ * in practice since the sampling thread won't be receiving many signals in
+ * the first place (it's a tools thread, so no STW), and because typical
+ * sleep periods for the thread are many orders of magnitude bigger than
+ * the time it takes to actually perform that system call (just a few
+ * nanoseconds).
+ */
+ do {
+ diff = (gint64) ns_abs - (gint64) clock_get_time_ns ();
+
+ if (diff <= 0)
+ break;
+
+ req.tv_sec = diff / 1000000000;
+ req.tv_nsec = diff % 1000000000;
+
+ if ((ret = nanosleep (&req, NULL)) == -1 && errno != EINTR)
+ g_error ("%s: nanosleep () returned -1, errno = %d", __func__, errno);
+ } while (ret == -1 && InterlockedRead (&sampling_thread_running));
+#endif
}
+
#endif
+static int profiler_signal;
+static volatile gint32 sampling_thread_exiting;
+
+static mono_native_thread_return_t
+sampling_thread_func (void *data)
+{
+ mono_threads_attach_tools_thread ();
+ mono_native_thread_set_name (mono_native_thread_id_get (), "Profiler sampler");
+
+ int old_policy;
+ struct sched_param old_sched;
+ pthread_getschedparam (pthread_self (), &old_policy, &old_sched);
+
+ /*
+ * Attempt to switch the thread to real time scheduling. This will not
+ * necessarily work on all OSs; for example, most Linux systems will give
+ * us EPERM here unless configured to allow this.
+ *
+ * TODO: This does not work on Mac (and maybe some other OSs). On Mac, we
+ * have to use the Mach thread policy routines to switch to real-time
+ * scheduling. This is quite tricky as we need to specify how often we'll
+ * be doing work (easy), the normal processing time needed (also easy),
+ * and the maximum amount of processing time needed (hard). This is
+ * further complicated by the fact that if we misbehave and take too long
+ * to do our work, the kernel may knock us back down to the normal thread
+ * scheduling policy without telling us.
+ */
+ struct sched_param sched = { .sched_priority = sched_get_priority_max (SCHED_FIFO) };
+ pthread_setschedparam (pthread_self (), SCHED_FIFO, &sched);
+
+ MonoProfilerSampleMode mode;
+
+init:
+ mono_profiler_get_sample_mode (NULL, &mode, NULL);
+
+ if (mode == MONO_PROFILER_SAMPLE_MODE_NONE) {
+ mono_profiler_sampling_thread_wait ();
+
+ if (!InterlockedRead (&sampling_thread_running))
+ goto done;
+
+ goto init;
+ }
+
+ clock_init (mode);
+
+ for (guint64 sleep = clock_get_time_ns (); InterlockedRead (&sampling_thread_running); clock_sleep_ns_abs (sleep)) {
+ uint32_t freq;
+ MonoProfilerSampleMode new_mode;
+
+ mono_profiler_get_sample_mode (NULL, &new_mode, &freq);
+
+ if (new_mode != mode) {
+ clock_cleanup ();
+ goto init;
+ }
+
+ sleep += 1000000000 / freq;
+
+ FOREACH_THREAD_SAFE (info) {
+ /* info should never be this thread as we're a tools thread. */
+ g_assert (mono_thread_info_get_tid (info) != mono_native_thread_id_get ());
+
+ /*
+ * Require an ack for the last sampling signal sent to the thread
+ * so that we don't overflow the signal queue, leading to all sorts
+ * of problems (e.g. GC STW failing).
+ */
+ if (profiler_signal != SIGPROF && !InterlockedCompareExchange (&info->profiler_signal_ack, 0, 1))
+ continue;
+
+ mono_threads_pthread_kill (info, profiler_signal);
+ InterlockedIncrement (&profiler_signals_sent);
+ } FOREACH_THREAD_SAFE_END
+ }
+
+ clock_cleanup ();
+
+done:
+ InterlockedWrite (&sampling_thread_exiting, 1);
+
+ pthread_setschedparam (pthread_self (), old_policy, &old_sched);
+
+ mono_thread_info_detach ();
+
+ return NULL;
+}
+
void
-mono_runtime_setup_stat_profiler (void)
+mono_runtime_shutdown_stat_profiler (void)
{
-#ifdef ITIMER_PROF
- struct itimerval itval;
- static int inited = 0;
-#ifdef HAVE_LINUX_RTC_H
- const char *rtc_freq;
- if (!inited && (rtc_freq = g_getenv ("MONO_RTC"))) {
- int freq = 0;
- inited = 1;
- if (*rtc_freq)
- freq = atoi (rtc_freq);
- if (!freq)
- freq = 1024;
- rtc_fd = open ("/dev/rtc", O_RDONLY);
- if (rtc_fd == -1) {
- perror ("open /dev/rtc");
- return;
- }
- profiling_signal_in_use = SIGPROF;
- add_signal_handler (profiling_signal_in_use, sigprof_signal_handler, SA_RESTART);
- if (ioctl (rtc_fd, RTC_IRQP_SET, freq) == -1) {
- perror ("set rtc freq");
- return;
- }
- if (ioctl (rtc_fd, RTC_PIE_ON, 0) == -1) {
- perror ("start rtc");
- return;
- }
- if (fcntl (rtc_fd, F_SETSIG, SIGPROF) == -1) {
- perror ("setsig");
- return;
- }
- if (fcntl (rtc_fd, F_SETOWN, getpid ()) == -1) {
- perror ("setown");
- return;
+ InterlockedWrite (&sampling_thread_running, 0);
+
+ mono_profiler_sampling_thread_post ();
+
+#ifndef HOST_DARWIN
+ /*
+ * There is a slight problem when we're using CLOCK_PROCESS_CPUTIME_ID: If
+ * we're shutting down and there's largely no activity in the process other
+ * than waiting for the sampler thread to shut down, it can take upwards of
+ * 20 seconds (depending on a lot of factors) for us to shut down because
+ * the sleep progresses very slowly as a result of the low CPU activity.
+ *
+ * We fix this by repeatedly sending the profiler signal to the sampler
+ * thread in order to interrupt the sleep. clock_sleep_ns_abs () will check
+ * sampling_thread_running upon an interrupt and return immediately if it's
+ * zero. profiler_signal_handler () has a special case to ignore the signal
+ * for the sampler thread.
+ */
+ MonoThreadInfo *info;
+
+ // Did it shut down already?
+ if ((info = mono_thread_info_lookup (sampling_thread))) {
+ while (!InterlockedRead (&sampling_thread_exiting)) {
+ mono_threads_pthread_kill (info, profiler_signal);
+ mono_thread_info_usleep (10 * 1000 /* 10ms */);
}
- enable_rtc_timer (TRUE);
- return;
+
+ // Make sure info can be freed.
+ mono_hazard_pointer_clear (mono_hazard_pointer_get (), 1);
}
- if (rtc_fd >= 0)
- return;
#endif
- itval.it_interval.tv_usec = (1000000 / mono_profiler_get_sampling_rate ()) - 1;
- itval.it_interval.tv_sec = 0;
- itval.it_value = itval.it_interval;
- if (inited)
- return;
- inited = 1;
- profiling_signal_in_use = get_itimer_signal ();
- add_signal_handler (profiling_signal_in_use, sigprof_signal_handler, SA_RESTART);
- setitimer (get_itimer_mode (), &itval, NULL);
-#endif
+ mono_native_thread_join (sampling_thread);
+
+ /*
+ * We can't safely remove the signal handler because we have no guarantee
+ * that all pending signals have been delivered at this point. This should
+ * not really be a problem anyway.
+ */
+ //remove_signal_handler (profiler_signal);
}
-#if !defined(PLATFORM_MACOSX)
-pid_t
-mono_runtime_syscall_fork ()
+void
+mono_runtime_setup_stat_profiler (void)
{
-#if defined(PLATFORM_ANDROID)
- /* SYS_fork is defined to be __NR_fork which is not defined in some ndk versions */
- g_assert_not_reached ();
- return 0;
-#elif defined(SYS_fork)
- return (pid_t) syscall (SYS_fork);
+ /*
+ * Use a real-time signal when possible. This gives us roughly a 99% signal
+ * delivery rate in all cases. On the other hand, using a regular signal
+ * tends to result in awful delivery rates when the application is heavily
+ * loaded.
+ *
+ * We avoid real-time signals on Android as they're super broken in certain
+ * API levels (too small sigset_t, nonsensical SIGRTMIN/SIGRTMAX values,
+ * etc).
+ *
+ * TODO: On Mac, we should explore using the Mach thread suspend/resume
+ * functions and doing the stack walk from the sampling thread. This would
+ * get us a 100% sampling rate. However, this may interfere with the GC's
+ * STW logic. Could perhaps be solved by taking the suspend lock.
+ */
+#if defined (USE_POSIX_BACKEND) && defined (SIGRTMIN) && !defined (HOST_ANDROID)
+ /* Just take the first real-time signal we can get. */
+ profiler_signal = mono_threads_suspend_search_alternative_signal ();
#else
- g_assert_not_reached ();
- return 0;
+ profiler_signal = SIGPROF;
#endif
+
+ add_signal_handler (profiler_signal, profiler_signal_handler, SA_RESTART);
+
+ mono_counters_register ("Sampling signals sent", MONO_COUNTER_UINT | MONO_COUNTER_PROFILER | MONO_COUNTER_MONOTONIC, &profiler_signals_sent);
+ mono_counters_register ("Sampling signals received", MONO_COUNTER_UINT | MONO_COUNTER_PROFILER | MONO_COUNTER_MONOTONIC, &profiler_signals_received);
+ mono_counters_register ("Sampling signals accepted", MONO_COUNTER_UINT | MONO_COUNTER_PROFILER | MONO_COUNTER_MONOTONIC, &profiler_signals_accepted);
+ mono_counters_register ("Shutdown signals received", MONO_COUNTER_UINT | MONO_COUNTER_PROFILER | MONO_COUNTER_MONOTONIC, &profiler_interrupt_signals_received);
+
+ InterlockedWrite (&sampling_thread_running, 1);
+ mono_native_thread_create (&sampling_thread, sampling_thread_func, NULL);
+}
+
+#else
+
+void
+mono_runtime_shutdown_stat_profiler (void)
+{
+}
+
+void
+mono_runtime_setup_stat_profiler (void)
+{
+}
+
+#endif
+
+#endif /* defined(HOST_WATCHOS) */
+
+static gboolean
+native_stack_with_gdb (pid_t crashed_pid, const char **argv, FILE *commands, char* commands_filename)
+{
+ gchar *gdb;
+
+ gdb = g_find_program_in_path ("gdb");
+ if (!gdb)
+ return FALSE;
+
+ argv [0] = gdb;
+ argv [1] = "-batch";
+ argv [2] = "-x";
+ argv [3] = commands_filename;
+ argv [4] = "-nx";
+
+ fprintf (commands, "attach %ld\n", (long) crashed_pid);
+ fprintf (commands, "info threads\n");
+ fprintf (commands, "thread apply all bt\n");
+
+ return TRUE;
+}
+
+
+static gboolean
+native_stack_with_lldb (pid_t crashed_pid, const char **argv, FILE *commands, char* commands_filename)
+{
+ gchar *lldb;
+
+ lldb = g_find_program_in_path ("lldb");
+ if (!lldb)
+ return FALSE;
+
+ argv [0] = lldb;
+ argv [1] = "--batch";
+ argv [2] = "--source";
+ argv [3] = commands_filename;
+ argv [4] = "--no-lldbinit";
+
+ fprintf (commands, "process attach --pid %ld\n", (long) crashed_pid);
+ fprintf (commands, "thread list\n");
+ fprintf (commands, "thread backtrace all\n");
+ fprintf (commands, "detach\n");
+ fprintf (commands, "quit\n");
+
+ return TRUE;
}
void
mono_gdb_render_native_backtraces (pid_t crashed_pid)
{
- const char *argv [9];
- char template_ [] = "/tmp/mono-lldb-commands.XXXXXX";
- char buf1 [128];
+#ifdef HAVE_EXECV
+ const char *argv [10];
FILE *commands;
- gboolean using_lldb = FALSE;
+ char commands_filename [] = "/tmp/mono-gdb-commands.XXXXXX";
- argv [0] = g_find_program_in_path ("gdb");
- if (argv [0] == NULL) {
- argv [0] = g_find_program_in_path ("lldb");
- using_lldb = TRUE;
- }
+ if (mkstemp (commands_filename) == -1)
+ return;
- if (argv [0] == NULL)
+ commands = fopen (commands_filename, "w");
+ if (!commands) {
+ unlink (commands_filename);
return;
+ }
- if (using_lldb) {
- if (mkstemp (template_) == -1)
- return;
+ memset (argv, 0, sizeof (char*) * 10);
+
+#if defined(HOST_DARWIN)
+ if (native_stack_with_lldb (crashed_pid, argv, commands, commands_filename))
+ goto exec;
+#endif
- commands = fopen (template_, "w");
+ if (native_stack_with_gdb (crashed_pid, argv, commands, commands_filename))
+ goto exec;
- fprintf (commands, "process attach --pid %ld\n", (long) crashed_pid);
- fprintf (commands, "thread list\n");
- fprintf (commands, "thread backtrace all\n");
- fprintf (commands, "detach\n");
- fprintf (commands, "quit\n");
+#if !defined(HOST_DARWIN)
+ if (native_stack_with_lldb (crashed_pid, argv, commands, commands_filename))
+ goto exec;
+#endif
- fflush (commands);
- fclose (commands);
+ fprintf (stderr, "mono_gdb_render_native_backtraces not supported on this platform, unable to find gdb or lldb\n");
- argv [1] = "--source";
- argv [2] = template_;
- argv [3] = 0;
- } else {
- argv [1] = "-ex";
- sprintf (buf1, "attach %ld", (long) crashed_pid);
- argv [2] = buf1;
- argv [3] = "--ex";
- argv [4] = "info threads";
- argv [5] = "--ex";
- argv [6] = "thread apply all bt";
- argv [7] = "--batch";
- argv [8] = 0;
- }
+ fclose (commands);
+ unlink (commands_filename);
+ return;
+exec:
+ fclose (commands);
execv (argv [0], (char**)argv);
- if (using_lldb)
- unlink (template_);
+ _exit (-1);
+#else
+ fprintf (stderr, "mono_gdb_render_native_backtraces not supported on this platform\n");
+#endif // HAVE_EXECV
}
-#endif
-#endif /* __native_client__ */
#if !defined (__MACH__)
projects / mono.git / blobdiff