Il 09/01/2014 22:14, thomas knych ha scritto:
> Upstreaming this change from Android
> (https://android-review.googlesource.com/54211).
>
> On heavily loaded machines with many VM instances we see KVM_CREATE_VM
> failing with EINTR/EAGAIN retrying the system call greatly improves
> reliability.
>
> Signed-off-by: thomas knych <thoma...@google.com>
> ---
> kvm-all.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/kvm-all.c b/kvm-all.c
> index 3937754..29787ae 100644
> --- a/kvm-all.c
> +++ b/kvm-all.c
> @@ -1442,8 +1442,14 @@ int kvm_init(void)
> nc++;
> }
>
> - s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
> + do {
> + s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
> + } while (s->vmfd < 0 && (-EINTR == s->vmfd || -EAGAIN == s->vmfd));
No yoda conditionals---please write "s->vmfd == -EINTR".
However, I would like to understand where in the KVM module the error
originates and is propagated from. Especially EAGAIN seems weird.
Paolo
> +
> if (s->vmfd < 0) {
> + fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %d %s\n", -s->vmfd,
> + strerror(-s->vmfd));
> +
> #ifdef TARGET_S390X
> fprintf(stderr, "Please add the 'switch_amode' kernel parameter to "
> "your host kernel command line\n");
>
