Re: [PATCH 1/6] rcu,nohz: add context_tracking_user_enter/exit wrapper functions

From: Paul E. McKenney
Date: Tue Feb 10 2015 - 12:49:48 EST


On Tue, Feb 10, 2015 at 06:36:47PM +0100, Frederic Weisbecker wrote:
> On Tue, Feb 10, 2015 at 09:25:26AM -0800, Paul E. McKenney wrote:
> > On Tue, Feb 10, 2015 at 11:48:37AM -0500, Rik van Riel wrote:
> > > On 02/10/2015 10:28 AM, Frederic Weisbecker wrote:
> > > > On Tue, Feb 10, 2015 at 09:41:45AM -0500, riel@xxxxxxxxxx wrote:
> > > >> From: Rik van Riel <riel@xxxxxxxxxx>
> > > >>
> > > >> These wrapper functions allow architecture code (eg. ARM) to keep
> > > >> calling context_tracking_user_enter & context_tracking_user_exit
> > > >> the same way it always has, without error prone tricks like duplicate
> > > >> defines of argument values in assembly code.
> > > >>
> > > >> Signed-off-by: Rik van Riel <riel@xxxxxxxxxx>
> > > >
> > > > This patch alone doesn't make much sense.
> > >
> > > Agreed, my goal was to keep things super easy to review,
> > > to reduce the chance of introducing bugs.
> > >
> > > > The changelog says it's about keeping
> > > > context_tracking_user_*() functions as wrappers but fails to explain to what they
> > > > wrap, why and what are the new context_tracking_enter/exit functions for.
> > > >
> > > > Perhaps patches 1 and 2 should be merged together into something like:
> > > >
> > > > context_tracking: Generalize context tracking APIs to support user and guest
> > > >
> > > > Do that because we'll also track guest....etc And keep the old user context tracking APIs
> > > > for now to avoid painful enum parameter support in ARM assembly....
> > >
> > > Can do...
> > >
> > > Paul, would you like me to resend the whole series, or just
> > > a merged patch that replaces patches 1 & 2?
> >
> > I prefer the whole series, as it reduces my opportunity to introduce
> > human error when applying them. ;-)
> >
> > > That is assuming Paul prefers having the patches merged into
> > > one :)
> >
> > I am OK with that. I will merge the next set with the first two patches
> > merged, people have had sufficient opportunity to review.
>
> BTW, I have a few patches to make on the next cycle to fix a few context tracking
> related things. And since it's too late to push this series for the current merge window,
> now I wonder it may be easier if I take these patches. Otherwise you might experience
> unpleasant rebase conflicts. Is that ok for you?

Works for me! ;-)

Thanx, Paul

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