Re: [PATCH v1 3/3] locking/lockdep,doc: Correct the max number of lock classes
From: Xiongwei Song
Date: Mon Jul 12 2021 - 04:39:23 EST
On Sun, Jul 11, 2021 at 11:22 PM Waiman Long <llong@xxxxxxxxxx> wrote:
>
> On 7/11/21 10:14 AM, Xiongwei Song wrote:
> > From: Xiongwei Song <sxwjean@xxxxxxxxx>
> >
> > The max number of lock classes is 8192.
> >
> > Signed-off-by: Xiongwei Song <sxwjean@xxxxxxxxx>
> > Cc: Jonathan Corbet <corbet@xxxxxxx>
> > Cc: linux-doc@xxxxxxxxxxxxxxx
> > ---
> > Documentation/locking/lockdep-design.rst | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/Documentation/locking/lockdep-design.rst b/Documentation/locking/lockdep-design.rst
> > index 82f36cab61bd..5c2dcec684ff 100644
> > --- a/Documentation/locking/lockdep-design.rst
> > +++ b/Documentation/locking/lockdep-design.rst
> > @@ -341,7 +341,7 @@ Exceeding this number will trigger the following lockdep warning::
> >
> > (DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS))
> >
> > -By default, MAX_LOCKDEP_KEYS is currently set to 8191, and typical
> > +By default, MAX_LOCKDEP_KEYS is currently set to 8192, and typical
> > desktop systems have less than 1,000 lock classes, so this warning
> > normally results from lock-class leakage or failure to properly
> > initialize locks. These two problems are illustrated below:
> > @@ -383,7 +383,7 @@ you the number of lock classes currently in use along with the maximum::
> >
> > This command produces the following output on a modest system::
> >
> > - lock-classes: 748 [max: 8191]
> > + lock-classes: 748 [max: 8192]
> >
> > If the number allocated (748 above) increases continually over time,
> > then there is likely a leak. The following command can be used to
>
> Acked-by: Waiman Long <longman@xxxxxxxxxx>
Thanks.