Re: [libvirt] [PATCH] cgroup: Add missing errno == ENOENT check in virCgroupRemoveRecursively
On Tue, Jun 29, 2010 at 1:41 AM, Eric Blake <eblake(a)redhat.com> wrote:
On 06/26/2010 11:21 AM, Ryota Ozaki wrote:
> ENOENT happens normally when a subsystem is enabled with any other
> subsystems and the directory of the target group has already removed
> in a prior loop. In that case, the function should just return without
> leaving an error message.
>
> NB this is the same behavior as before introducing virCgroupRemoveRecursively.
> ---
> src/util/cgroup.c | 2 ++
> 1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/src/util/cgroup.c b/src/util/cgroup.c
> index 62b1446..9fa64dc 100644
> --- a/src/util/cgroup.c
> +++ b/src/util/cgroup.c
> @@ -616,6 +616,8 @@ static int virCgroupRemoveRecursively(char *grppath)
>
> grpdir = opendir(grppath);
> if (grpdir == NULL) {
> + if (errno == ENOENT)
> + return 0;
Shouldn't this be continue instead of return 0, so as to go on to the
next readdir() in case there is anything else in the directory?
The next readdir() and mkdir() following to it are for the directory (e.g.,
/a/b/c) and its inclusions (e.g., /a/b/c/d). We cannot go on if the directory
(a/b/c) does not present. Other sibling directories of the directory (e.g,
/a/b/d) will be handled in the caller function.
Well, am I missing your question?
Also, right now, your cgroup recursive delete is breaking compilation on
mingw, which lacks d_type. Obviously, since mingw also lacks cgroup
altogether, we can make things conditional, but I haven't had time to
look into the correct fix for that yet.
If we follow the same workaround as doing for virCgroupForDriver,
it'll be like this:
#if defined _DIRENT_HAVE_D_TYPE
static int virCgroupRemoveRecursively(char *grppath)
{
...
}
#else
static int virCgroupRemoveRecursively(char *grppath ATTRIBUTE_UNUSED)
{
/* Claim no support */
return -ENXIO;
}
#endif
I'm not sure it's sane though, it'll work...
ozaki-r
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library http://libvirt.org