Re: [PATCH 0/4] RCU: various merge candidates

[Dipankar Sarma <dipankar@in.ibm.com>]

On Mon, Aug 28, 2006 at 06:15:48PM +0200, Arjan van de Ven wrote:
> On Mon, 2006-08-28 at 21:38 +0530, Dipankar Sarma wrote:
> > This patchset consists of various merge candidates that would
> > do well to have some testing in -mm. This patchset breaks
> > out RCU implementation from its APIs to allow multiple
> > implementations, 
> 
> 
> can you explain why we would want multiple RCU implementations?
> Isn't one going to be plenty already?

Hi Arjan,

See this for a background - http://lwn.net/Articles/129511/

Primarily, rcupreempt allows read-side critical sections to
be preempted unline classic RCU currently in mainline. It is
also a bit more aggressive in terms of grace periods by counting
the number of readers as opposed to periodic checks in classic
RCU.

The hope is that it will help mainline users who look for
better latency.

Thanks
Dipankar