Re: [Intel-IOMMU 02/10] Library routines for handling pre-allocated pool of objects

["Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>]

On Mon, Jun 04, 2007 at 07:43:54PM -0400, Jeff Garzik wrote:
> On Mon, Jun 04, 2007 at 04:06:49PM -0700, Keshavamurthy, Anil S wrote:
> > On Mon, Jun 04, 2007 at 06:57:14PM -0400, Jeff Garzik wrote:
> > > you should add logic to free resources here (or queue_work to free the
> > > resources), if the pool grows beyond a certain size.
> 
> > Can be added as an add on, testing showed that pool 
> > grows to a certain size and will not grow beyond that 
> > as we tend to reuse the elements.
> 
> Yes, but is it possible?  If no, what part of the code guarantees the
> pool is limited?
> 
> We should not merge code that allows the pool to grow without bound.
> In-house testing certainly never covers all the cases seen in the
> field, so I wouldn't make too many assumptions based on that.  Some
> vendor will inevitably build a $BigNum system where the IOMMU is very
> heavily used.

No problem, I can add the code to free the pool element if
the curr_count ever goes greater than (min_count + 2 * grow_count)
then bring the curr_count to min_count + grow_count by freeing 
some pool objects.

A patch which will apply to this current patch will follow soon.

Thanks Jeff for making your case stronger :)

-Anil


> 
> 	Jeff
> 
-
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/