Hi Anthony, How is -no-kvm-irqchip working with the patch?
On Tue, Apr 29, 2008 at 09:28:14AM -0500, Anthony Liguori wrote: > This patch eliminates the use of sigtimedwait() in the IO thread. To avoid > the > signal/select race condition, we use a pipe that we write to in the signal > handlers. This was suggested by Rusty and seems to work well. > > +static int kvm_eat_signal(CPUState *env, int timeout) > { > struct timespec ts; > int r, e, ret = 0; > siginfo_t siginfo; > + sigset_t waitset; > > + sigemptyset(&waitset); > + sigaddset(&waitset, SIG_IPI); > ts.tv_sec = timeout / 1000; > ts.tv_nsec = (timeout % 1000) * 1000000; > - r = sigtimedwait(&waitset->sigset, &siginfo, &ts); > + qemu_kvm_unlock(); > + r = sigtimedwait(&waitset, &siginfo, &ts); > + qemu_kvm_lock(env); > + cpu_single_env = env; This assignment seems redundant now. > if (r == -1 && (errno == EAGAIN || errno == EINTR) && !timeout) > return 0; > e = errno; > - pthread_mutex_lock(&qemu_mutex); > if (env && vcpu) > cpu_single_env = vcpu->env; And this one too. > > @@ -263,12 +238,8 @@ static void pause_all_threads(void) > vcpu_info[i].stop = 1; > pthread_kill(vcpu_info[i].thread, SIG_IPI); Make sure the IO thread has SIG_IPI blocked (those are for APIC vcpu initialization only). > +static void sig_aio_fd_read(void *opaque) > +{ > + int signum; > + ssize_t len; > + > + do { > + len = read(kvm_sigfd[0], &signum, sizeof(signum)); > + } while (len == -1 && errno == EINTR); What is the reason for this loop instead of a straight read? Its alright to be interrupted by a signal. > + signal(SIGUSR1, sig_aio_handler); > + signal(SIGUSR2, sig_aio_handler); > + signal(SIGALRM, sig_aio_handler); > + signal(SIGIO, sig_aio_handler); > + > + if (pipe(kvm_sigfd) == -1) > + abort(); perror() would be nice. > - kvm_eat_signal(&io_signal_table, NULL, 1000); > pthread_mutex_lock(&qemu_mutex); > - cpu_single_env = NULL; > - main_loop_wait(0); > + main_loop_wait(10); Increase that 1000 or something. Will make it easier to spot bugs. Similarly in qemu_kvm_aio_wait(). ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel