lkml.org 
[lkml]   [2004]   [Aug]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [RFC&PATCH] Alternative RCU implementation
From
Date
On Mon, 2004-08-30 at 13:38, Dipankar Sarma wrote:

> > I'm also trying to figure out if I need the call_rcu_bh() changes.
> > Since my patch will recognize a grace periods as soon as any
> > pending read-side critical sections complete, I suspect that I
> > don't need this change.
>
> Except that under a softirq flood, a reader in a different read-side
> critical section may get delayed a lot holding up RCU. Let me know
> if I am missing something here.

Hi Dipankar,

O.k. That makes sense. So the rcu_read_lock_bh(), rcu_read_unlock_bh()
and call_rcu_bh() would be the preferred interface. Are there cases
where they can't be used? How do you decide where to use the _bh
flavor?

I see that local_bh_enable() WARNS if interrupts are disabled. Is that
the issue? Are rcu_read_lock()/rcu_read_unlock() ever called from
code which disables interrupts?

Jim Houston - Concurrent Computer Corp.

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

\
 
 \ /
  Last update: 2005-03-22 14:05    [W:0.075 / U:0.332 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site