Re: [PATCH V6 07/10] sched: add a macro to ref all CLONE_NEW* flags

From: Richard Guy Briggs
Date: Fri Apr 17 2015 - 18:00:49 EST


On 15/04/17, Peter Zijlstra wrote:
> On Fri, Apr 17, 2015 at 11:42:50AM -0400, Richard Guy Briggs wrote:
> > On 15/04/17, Peter Zijlstra wrote:
> > > On Fri, Apr 17, 2015 at 03:35:54AM -0400, Richard Guy Briggs wrote:
> > > > Added the macro CLONE_NEW_MASK_ALL to refer to all CLONE_NEW* flags.
> > >
> > > A wee bit about why might be nice..
> >
> > It makes the following patch much cleaner to read:
> > [PATCH V6 08/10] fork: audit on creation of new namespace(s)
> > https://lkml.org/lkml/2015/4/17/50
> >
> > I was hoping it might also make a lot of other code cleaner, but most of
> > the other places where multiple CLONE_NEW* flags are used, not all six
> > are used together, but only 5 are used. Ok, so it is helpful in 1 of 3:
> >
> > It would actually be useful in check_unshare_flags():
> > https://github.com/torvalds/linux/blob/v3.17/kernel/fork.c#L1791
> >
> > but not in copy_namespaces() or unshare_nsproxy_namespaces():
> > https://github.com/torvalds/linux/blob/v3.17/kernel/nsproxy.c#L130
> > https://github.com/torvalds/linux/blob/v3.17/kernel/nsproxy.c#L183
>
> Right, so no objections from me on this, its just that I only saw this
> one patch in isolation without context and the changelog failed on
> rationale.

I realize you only saw a small window of this patchset, but this feels
like bike shedding about the main objective of the set...

I'll add a bit more justification and context if/when I respin for the
rest of the set.

> Does it perchance make sense to fold this patch into the next patch that
> actually makes use of it?

It would if it were the only potential user. I don't want to bury a
surprise in something bigger. Is there a preferred way to use such a
macro to make the other three examples cleaner, or is that just useless
churn and obfuscation? Would there be a concise way to express all
CLONE_NEW* flags *except* user?

- RGB

--
Richard Guy Briggs <rbriggs@xxxxxxxxxx>
Senior Software Engineer, Kernel Security, AMER ENG Base Operating Systems, Red Hat
Remote, Ottawa, Canada
Voice: +1.647.777.2635, Internal: (81) 32635, Alt: +1.613.693.0684x3545
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/