Re: [PATCH v1 5/5] kvfree_rcu: Fix comments according to current code

From: Uladzislau Rezki
Date: Mon May 03 2021 - 15:34:24 EST


> On Wed, Apr 28, 2021 at 03:44:22PM +0200, Uladzislau Rezki (Sony) wrote:
> > We used to have an "emergency path" and comments related
> > to it. According to current kvfree_rcu() design that path
> > is not considered as emergency anymore.
> >
> > This patch rephrases and updates comments regarding this.
> >
> > Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
>
> Queued as follows, thank you! Please check my usual wordsmithing to
> make sure that I did not mess anything up.
>
> Thanx, Paul
>
> ------------------------------------------------------------------------
>
> commit 06c2113c4b1ce9ded69cd0ac4da9a00ed6be8834
> Author: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> Date: Wed Apr 28 15:44:22 2021 +0200
>
> kvfree_rcu: Fix comments according to current code
>
> The kvfree_rcu() function now defers allocations in the common
> case due to the fact that there is no lockless access to the
> memory-allocator caches/pools. In addition, in CONFIG_PREEMPT_NONE=y
> and in CONFIG_PREEMPT_VOLUNTARY=y kernels, there is no reliable way to
> determine if spinlocks are held. As a result, allocation is deferred in
> the common case, and the two-argument form of kvfree_rcu() thus uses the
> "channel 3" queue through all the rcu_head structures. This channel
> is called referred to as the emergency case in comments, and these
> comments are now obsolete.
>
> This commit therefore updates these comments to reflect the new
> common-case nature of such emergencies.
>
> Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
>
Looks good to me.

--
Vlad Rezki