Commit 1a28cac3 authored by Marcelo Tosatti's avatar Marcelo Tosatti

make SIG_IPI to tcg vcpu thread reliable

Store tcg loop exit request on a global variable, and transfer it to
per-CPUState exit_request after assignment of cpu_single_env.

This makes exit request signal from robust. Drop the timedlock hack.
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 273faf1b
......@@ -213,6 +213,8 @@ static void cpu_handle_debug_exception(CPUState *env)
/* main execution loop */
volatile sig_atomic_t exit_request;
int cpu_exec(CPUState *env1)
{
volatile host_reg_t saved_env_reg;
......@@ -234,6 +236,11 @@ int cpu_exec(CPUState *env1)
asm("");
env = env1;
if (exit_request) {
env->exit_request = 1;
exit_request = 0;
}
#if defined(TARGET_I386)
if (!kvm_enabled()) {
/* put eflags in CPU temporary format */
......
......@@ -472,6 +472,7 @@ static void cpu_signal(int sig)
{
if (cpu_single_env)
cpu_exit(cpu_single_env);
exit_request = 1;
}
static void tcg_block_io_signals(void)
......@@ -542,26 +543,20 @@ static void unblock_io_signals(void)
pthread_sigmask(SIG_BLOCK, &set, NULL);
}
static void qemu_signal_lock(unsigned int msecs)
{
qemu_mutex_lock(&qemu_fair_mutex);
while (qemu_mutex_trylock(&qemu_global_mutex)) {
qemu_thread_signal(tcg_cpu_thread, SIG_IPI);
if (!qemu_mutex_timedlock(&qemu_global_mutex, msecs))
break;
}
qemu_mutex_unlock(&qemu_fair_mutex);
}
void qemu_mutex_lock_iothread(void)
{
if (kvm_enabled()) {
qemu_mutex_lock(&qemu_fair_mutex);
qemu_mutex_lock(&qemu_global_mutex);
qemu_mutex_unlock(&qemu_fair_mutex);
} else
qemu_signal_lock(100);
} else {
qemu_mutex_lock(&qemu_fair_mutex);
if (qemu_mutex_trylock(&qemu_global_mutex)) {
qemu_thread_signal(tcg_cpu_thread, SIG_IPI);
qemu_mutex_lock(&qemu_global_mutex);
}
qemu_mutex_unlock(&qemu_fair_mutex);
}
}
void qemu_mutex_unlock_iothread(void)
......
......@@ -351,4 +351,7 @@ CPUDebugExcpHandler *cpu_set_debug_excp_handler(CPUDebugExcpHandler *handler);
/* vl.c */
extern int singlestep;
/* cpu-exec.c */
extern volatile sig_atomic_t exit_request;
#endif
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