Re: [Qemu-devel] [PATCHv2] Add compat eventfd header

[Paolo Bonzini <pbonzini@redhat.com>]

On 06/30/2011 05:57 PM, Michael S. Tsirkin wrote:
> Support build on rhel 5.X where we have syscall for eventfd but not
> userspace wrapper.
>
> (cherry-picked from commit 9e3269181e9bc56feb43bcd4e8ce0b82cd543e65
>   in qemu-kvm.git).
>
> Signed-off-by: Michael S. Tsirkin<mst@redhat.com>
> ---
>
> Changes from v1:
>    checkpatch fix
>    address comments by agraf
>    verify we are on linux
>
>   compat/sys/eventfd.h |   20 ++++++++++++++++++++
>   configure            |    6 ++++--
>   2 files changed, 24 insertions(+), 2 deletions(-)
>   create mode 100644 compat/sys/eventfd.h
>
> diff --git a/compat/sys/eventfd.h b/compat/sys/eventfd.h
> new file mode 100644
> index 0000000..1801a5f
> --- /dev/null
> +++ b/compat/sys/eventfd.h
> @@ -0,0 +1,20 @@
> +#ifndef _COMPAT_SYS_EVENTFD
> +#define _COMPAT_SYS_EVENTFD
> +
> +#ifdef CONFIG_EVENTFD
> +
> +#ifndef __linux__
> +#error __linux__ is not defined: eventfd is only supported on linux
> +#endif
> +
> +#include<unistd.h>
> +#include<syscall.h>
> +
> +static inline int eventfd(int count, int flags)
> +{
> +    return syscall(SYS_eventfd, count, flags);
> +}
> +
> +#endif
> +
> +#endif
> diff --git a/configure b/configure
> index 856b41e..6f7dd74 100755
> --- a/configure
> +++ b/configure
> @@ -822,7 +822,6 @@ esac
>
>   [ -z "$guest_base" ]&&  guest_base="$host_guest_base"
>
> -
>   default_target_list=""
>
>   # these targets are portable
> @@ -891,6 +890,9 @@ sparc64-bsd-user \
>   "
>   fi
>
> +#compat headers
> +QEMU_CFLAGS="$QEMU_CFLAGS -idirafter $source_path/compat"
> +
>   if test x"$show_help" = x"yes" ; then
>   cat<<  EOF
>
> @@ -2122,7 +2124,7 @@ int main(void)
>       return 0;
>   }
>   EOF
> -if compile_prog "" "" ; then
> +if compile_prog "-DCONFIG_EVENTFD" "" ; then
>     eventfd=yes
>   fi
>

Acked-by: Paolo Bonzini <pbonzini@redhat.com>

Paolo