Re: [Qemu-devel] [PATCH] make qemu_thread_create block all signals

[Anthony Liguori <anthony@codemonkey.ws>]

On 06/03/2010 08:20 AM, Paolo Bonzini wrote:
> All signals will thus be routed through the IO thread.
>
> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
>    

Applied.  Thanks.

Regards,

Anthony Liguori

> ---
>   cpus.c        |   38 +++++++++++---------------------------
>   qemu-thread.c |    7 +++++++
>   2 files changed, 18 insertions(+), 27 deletions(-)
>
> diff --git a/cpus.c b/cpus.c
> index 8341f6c..fcd0f09 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -318,8 +318,8 @@ static QemuCond qemu_system_cond;
>   static QemuCond qemu_pause_cond;
>   static QemuCond qemu_work_cond;
>
> -static void tcg_block_io_signals(void);
> -static void kvm_block_io_signals(CPUState *env);
> +static void tcg_init_ipi(void);
> +static void kvm_init_ipi(CPUState *env);
>   static void unblock_io_signals(void);
>
>   int qemu_init_main_loop(void)
> @@ -464,7 +464,7 @@ static void *kvm_cpu_thread_fn(void *arg)
>       if (kvm_enabled())
>           kvm_init_vcpu(env);
>
> -    kvm_block_io_signals(env);
> +    kvm_init_ipi(env);
>
>       /* signal CPU creation */
>       env->created = 1;
> @@ -487,7 +487,7 @@ static void *tcg_cpu_thread_fn(void *arg)
>   {
>       CPUState *env = arg;
>
> -    tcg_block_io_signals();
> +    tcg_init_ipi();
>       qemu_thread_self(env->thread);
>
>       /* signal CPU creation */
> @@ -532,52 +532,36 @@ static void cpu_signal(int sig)
>       exit_request = 1;
>   }
>
> -static void tcg_block_io_signals(void)
> +static void tcg_init_ipi(void)
>   {
>       sigset_t set;
>       struct sigaction sigact;
>
> -    sigemptyset(&set);
> -    sigaddset(&set, SIGUSR2);
> -    sigaddset(&set, SIGIO);
> -    sigaddset(&set, SIGALRM);
> -    sigaddset(&set, SIGCHLD);
> -    pthread_sigmask(SIG_BLOCK,&set, NULL);
> +    memset(&sigact, 0, sizeof(sigact));
> +    sigact.sa_handler = cpu_signal;
> +    sigaction(SIG_IPI,&sigact, NULL);
>
>       sigemptyset(&set);
>       sigaddset(&set, SIG_IPI);
>       pthread_sigmask(SIG_UNBLOCK,&set, NULL);
> -
> -    memset(&sigact, 0, sizeof(sigact));
> -    sigact.sa_handler = cpu_signal;
> -    sigaction(SIG_IPI,&sigact, NULL);
>   }
>
>   static void dummy_signal(int sig)
>   {
>   }
>
> -static void kvm_block_io_signals(CPUState *env)
> +static void kvm_init_ipi(CPUState *env)
>   {
>       int r;
>       sigset_t set;
>       struct sigaction sigact;
>
> -    sigemptyset(&set);
> -    sigaddset(&set, SIGUSR2);
> -    sigaddset(&set, SIGIO);
> -    sigaddset(&set, SIGALRM);
> -    sigaddset(&set, SIGCHLD);
> -    sigaddset(&set, SIG_IPI);
> -    pthread_sigmask(SIG_BLOCK,&set, NULL);
> -
> -    pthread_sigmask(SIG_BLOCK, NULL,&set);
> -    sigdelset(&set, SIG_IPI);
> -
>       memset(&sigact, 0, sizeof(sigact));
>       sigact.sa_handler = dummy_signal;
>       sigaction(SIG_IPI,&sigact, NULL);
>
> +    pthread_sigmask(SIG_BLOCK, NULL,&set);
> +    sigdelset(&set, SIG_IPI);
>       r = kvm_set_signal_mask(env,&set);
>       if (r) {
>           fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(r));
> diff --git a/qemu-thread.c b/qemu-thread.c
> index 3923db7..faf4061 100644
> --- a/qemu-thread.c
> +++ b/qemu-thread.c
> @@ -137,9 +137,16 @@ void qemu_thread_create(QemuThread *thread,
>   {
>       int err;
>
> +    /* Leave signal handling to the iothread.  */
> +    sigset_t set, oldset;
> +
> +    sigfillset(&set);
> +    pthread_sigmask(SIG_SETMASK,&set,&oldset);
>       err = pthread_create(&thread->thread, NULL, start_routine, arg);
>       if (err)
>           error_exit(err, __func__);
> +
> +    pthread_sigmask(SIG_SETMASK,&oldset, NULL);
>   }
>
>   void qemu_thread_signal(QemuThread *thread, int sig)
>