[Qemu-devel] Re: [PATCH 12/22] kvm: Call qemu_kvm_eat_signals also under !CONFIG_IOTHREAD

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2011-02-01 13:38, Marcelo Tosatti wrote:
> On Thu, Jan 27, 2011 at 02:09:56PM +0100, Jan Kiszka wrote:
>> Move qemu_kvm_eat_signals around and call it also when the IO-thread is
>> not used. Do not yet process SIGBUS, will be armed in a separate step.
>>
>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>> ---
>>  cpus.c |   88 ++++++++++++++++++++++++++++++++++++---------------------------
>>  1 files changed, 50 insertions(+), 38 deletions(-)
>>
>> diff --git a/cpus.c b/cpus.c
>> index 9071848..558c0d3 100644
>> --- a/cpus.c
>> +++ b/cpus.c
>> @@ -261,6 +261,45 @@ static void qemu_kvm_init_cpu_signals(CPUState *env)
>>      }
>>  }
>>  
>> +static void qemu_kvm_eat_signals(CPUState *env)
>> +{
>> +    struct timespec ts = { 0, 0 };
>> +    siginfo_t siginfo;
>> +    sigset_t waitset;
>> +    sigset_t chkset;
>> +    int r;
>> +
>> +    sigemptyset(&waitset);
>> +    sigaddset(&waitset, SIG_IPI);
>> +    sigaddset(&waitset, SIGBUS);
>> +
>> +    do {
>> +        r = sigtimedwait(&waitset, &siginfo, &ts);
>> +        if (r == -1 && !(errno == EAGAIN || errno == EINTR)) {
>> +            perror("sigtimedwait");
>> +            exit(1);
>> +        }
>> +
>> +        switch (r) {
>> +#ifdef CONFIG_IOTHREAD
>> +        case SIGBUS:
>> +            if (kvm_on_sigbus_vcpu(env, siginfo.si_code, siginfo.si_addr)) {
>> +                sigbus_reraise();
>> +            }
>> +            break;
>> +#endif
>> +        default:
>> +            break;
>> +        }
>> +
>> +        r = sigpending(&chkset);
>> +        if (r == -1) {
>> +            perror("sigpending");
>> +            exit(1);
>> +        }
>> +    } while (sigismember(&chkset, SIG_IPI) || sigismember(&chkset, SIGBUS));
>> +}
>> +
>>  #else /* _WIN32 */
>>  
>>  HANDLE qemu_event_handle;
>> @@ -292,6 +331,10 @@ static void qemu_event_increment(void)
>>  static void qemu_kvm_init_cpu_signals(CPUState *env)
>>  {
>>  }
>> +
>> +static void qemu_kvm_eat_signals(CPUState *env)
>> +{
>> +}
>>  #endif /* _WIN32 */
>>  
>>  #ifndef CONFIG_IOTHREAD
>> @@ -631,43 +674,6 @@ static void sigbus_handler(int n, struct qemu_signalfd_siginfo *siginfo,
>>      }
>>  }
>>  
>> -static void qemu_kvm_eat_signals(CPUState *env)
>> -{
>> -    struct timespec ts = { 0, 0 };
>> -    siginfo_t siginfo;
>> -    sigset_t waitset;
>> -    sigset_t chkset;
>> -    int r;
>> -
>> -    sigemptyset(&waitset);
>> -    sigaddset(&waitset, SIG_IPI);
>> -    sigaddset(&waitset, SIGBUS);
>> -
>> -    do {
>> -        r = sigtimedwait(&waitset, &siginfo, &ts);
>> -        if (r == -1 && !(errno == EAGAIN || errno == EINTR)) {
>> -            perror("sigtimedwait");
>> -            exit(1);
>> -        }
>> -
>> -        switch (r) {
>> -        case SIGBUS:
>> -            if (kvm_on_sigbus_vcpu(env, siginfo.si_code, siginfo.si_addr)) {
>> -                sigbus_reraise();
>> -            }
>> -            break;
>> -        default:
>> -            break;
>> -        }
>> -
>> -        r = sigpending(&chkset);
>> -        if (r == -1) {
>> -            perror("sigpending");
>> -            exit(1);
>> -        }
>> -    } while (sigismember(&chkset, SIG_IPI) || sigismember(&chkset, SIGBUS));
>> -}
>> -
>>  static void qemu_kvm_wait_io_event(CPUState *env)
>>  {
>>      while (!cpu_has_work(env))
>> @@ -932,6 +938,8 @@ static int qemu_cpu_exec(CPUState *env)
>>  
>>  bool cpu_exec_all(void)
>>  {
>> +    int r;
>> +
>>      if (next_cpu == NULL)
>>          next_cpu = first_cpu;
>>      for (; next_cpu != NULL && !exit_request; next_cpu = next_cpu->next_cpu) {
>> @@ -943,7 +951,11 @@ bool cpu_exec_all(void)
>>          if (qemu_alarm_pending())
>>              break;
>>          if (cpu_can_run(env)) {
>> -            if (qemu_cpu_exec(env) == EXCP_DEBUG) {
>> +            r = qemu_cpu_exec(env);
>> +            if (kvm_enabled()) {
>> +                qemu_kvm_eat_signals(env);
>> +            }
>> +            if (r == EXCP_DEBUG) {
>>                  break;
>>              }
> 
> As mentioned before, signal processing should be independent of
> cpu_can_run (still want to process SIGALRM if vm is stopped, for
> example).
> 

For those signals that matter, it is.

Jan

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