Re: [PATCH tip/core/rcu 11/12] rcu: Make RCU able to tolerate undefined CONFIG_RCU_FANOUT_LEAF

2015-04-21 Thread Pranith Kumar 
On Tue, Apr 21, 2015 at 3:55 PM, Paul E. McKenney
 wrote:

> diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
> index 2e52502bfc95..a2f64e4fdb57 100644
> --- a/kernel/rcu/tree_plugin.h
> +++ b/kernel/rcu/tree_plugin.h
> @@ -86,10 +86,10 @@ static void __init rcu_bootup_announce_oddness(void)
> pr_info("\tAdditional per-CPU info printed with stalls.\n");
> if (RCU_NUM_LVLS >= 4)
> pr_info("\tFour(or more)-level hierarchy is enabled.\n");
> -   if (CONFIG_RCU_FANOUT_LEAF != 16)
> +   if (RCU_FANOUT_LEAF != 16)

So if CONFIG_RCU_FANOUT_LEAF is either by default 32 or 64, this check
against 16 for build-time adjustment is a bit misleading, no?

-- 
Pranith
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Re: [PATCH tip/core/rcu 11/12] rcu: Make RCU able to tolerate undefined CONFIG_RCU_FANOUT_LEAF

2015-04-22 Thread Paul E. McKenney 
On Wed, Apr 22, 2015 at 01:25:07AM -0400, Pranith Kumar wrote:
> On Tue, Apr 21, 2015 at 3:55 PM, Paul E. McKenney
>  wrote:
> 
> > diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
> > index 2e52502bfc95..a2f64e4fdb57 100644
> > --- a/kernel/rcu/tree_plugin.h
> > +++ b/kernel/rcu/tree_plugin.h
> > @@ -86,10 +86,10 @@ static void __init rcu_bootup_announce_oddness(void)
> > pr_info("\tAdditional per-CPU info printed with stalls.\n");
> > if (RCU_NUM_LVLS >= 4)
> > pr_info("\tFour(or more)-level hierarchy is enabled.\n");
> > -   if (CONFIG_RCU_FANOUT_LEAF != 16)
> > +   if (RCU_FANOUT_LEAF != 16)
> 
> So if CONFIG_RCU_FANOUT_LEAF is either by default 32 or 64, this check
> against 16 for build-time adjustment is a bit misleading, no?

Indeed!

However, with the fix that puts the default back to 16, this should be
once again correct.

Thanx, Paul

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/