2011-12-22 16:19:25 +01:00
|
|
|
/*
|
|
|
|
* \brief Implementation of the Thread API via Linux threads
|
|
|
|
* \author Norman Feske
|
|
|
|
* \date 2006-06-13
|
|
|
|
*/
|
|
|
|
|
|
|
|
/*
|
2012-01-03 15:35:05 +01:00
|
|
|
* Copyright (C) 2006-2012 Genode Labs GmbH
|
2011-12-22 16:19:25 +01:00
|
|
|
*
|
|
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
|
|
* under the terms of the GNU General Public License version 2.
|
|
|
|
*/
|
|
|
|
|
|
|
|
/* Genode includes */
|
|
|
|
#include <base/env.h>
|
|
|
|
#include <base/thread.h>
|
|
|
|
#include <base/snprintf.h>
|
|
|
|
#include <base/sleep.h>
|
2012-08-09 16:52:47 +02:00
|
|
|
#include <linux_cpu_session/linux_cpu_session.h>
|
2011-12-22 16:19:25 +01:00
|
|
|
|
|
|
|
/* Linux syscall bindings */
|
|
|
|
#include <linux_syscalls.h>
|
|
|
|
|
|
|
|
using namespace Genode;
|
|
|
|
|
|
|
|
|
|
|
|
static void empty_signal_handler(int) { }
|
|
|
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Signal handler for killing the thread
|
|
|
|
*/
|
|
|
|
static void thread_exit_signal_handler(int) { lx_exit(0); }
|
|
|
|
|
|
|
|
|
|
|
|
static void thread_start(void *)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Set signal handler such that canceled system calls get not
|
|
|
|
* transparently retried after a signal gets received.
|
|
|
|
*/
|
|
|
|
lx_sigaction(LX_SIGUSR1, empty_signal_handler);
|
|
|
|
|
2012-07-09 17:51:39 +02:00
|
|
|
/*
|
|
|
|
* Prevent children from becoming zombies. (SIG_IGN = 1)
|
|
|
|
*/
|
|
|
|
lx_sigaction(LX_SIGCHLD, (void (*)(int))1);
|
|
|
|
|
2011-12-22 16:19:25 +01:00
|
|
|
Thread_base::myself()->entry();
|
|
|
|
sleep_forever();
|
|
|
|
}
|
|
|
|
|
|
|
|
|
2012-08-09 16:52:47 +02:00
|
|
|
void Thread_base::_init_platform_thread()
|
|
|
|
{
|
|
|
|
_thread_cap = env()->cpu_session()->create_thread(_context->name);
|
|
|
|
}
|
2011-12-22 16:19:25 +01:00
|
|
|
|
|
|
|
|
|
|
|
void Thread_base::_deinit_platform_thread()
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Kill thread until it is really really dead
|
|
|
|
*
|
|
|
|
* We use the 'tgkill' system call to kill the thread. This system call
|
|
|
|
* returns immediately and just flags the corresponding signal at the
|
|
|
|
* targeted thread context. However, the thread still lives until the
|
|
|
|
* signal flags are evaluated. When leaving this function, however, we want
|
|
|
|
* to be sure that the thread is no more executing any code such that we
|
|
|
|
* an safely free and unmap the thread's stack. So we call 'tgkill' in a
|
|
|
|
* loop until we get an error indicating that the thread does not exists
|
|
|
|
* anymore.
|
|
|
|
*/
|
|
|
|
for (;;) {
|
|
|
|
|
|
|
|
/* destroy thread locally */
|
|
|
|
int ret = lx_tgkill(_tid.pid, _tid.tid, LX_SIGCANCEL);
|
|
|
|
|
|
|
|
if (ret < 0) break;
|
|
|
|
|
|
|
|
/* if thread still exists, wait a bit and try to kill it again */
|
|
|
|
struct timespec ts = { 0, 500 };
|
|
|
|
lx_nanosleep(&ts, 0);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* inform core about the killed thread */
|
|
|
|
env()->cpu_session()->kill_thread(_thread_cap);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Thread_base::start()
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* The first time we enter this code path, the 'start' function is
|
|
|
|
* called by the main thread as there cannot exist other threads
|
|
|
|
* without executing this function. When first called, we initialize
|
|
|
|
* the thread lib here.
|
|
|
|
*/
|
|
|
|
static bool threadlib_initialized = false;
|
|
|
|
if (!threadlib_initialized) {
|
|
|
|
lx_sigaction(LX_SIGCANCEL, thread_exit_signal_handler);
|
|
|
|
threadlib_initialized = true;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* align initial stack to 16 byte boundary */
|
|
|
|
void *thread_sp = (void *)((addr_t)(_context->stack) & ~0xf);
|
|
|
|
_tid.tid = lx_create_thread(thread_start, thread_sp, this);
|
|
|
|
_tid.pid = lx_getpid();
|
|
|
|
|
2012-08-09 16:52:47 +02:00
|
|
|
/* inform core about the new thread and process ID of the new thread */
|
|
|
|
Linux_cpu_session *cpu = dynamic_cast<Linux_cpu_session *>(env()->cpu_session());
|
|
|
|
if (cpu)
|
|
|
|
cpu->thread_id(_thread_cap, _tid.pid, _tid.tid);
|
2011-12-22 16:19:25 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Thread_base::cancel_blocking()
|
|
|
|
{
|
|
|
|
env()->cpu_session()->cancel_blocking(_thread_cap);
|
|
|
|
}
|