On Thu, Aug 07, 2014 at 10:11:14AM +0800, Zhang Yanfei wrote: > Hi Joonsoo, > > On 08/06/2014 03:18 PM, Joonsoo Kim wrote: > > per cpu pages structure, aka pcp, has high and batch values to control > > how many pages we perform caching. This values could be updated > > asynchronously and updater should ensure that this doesn't make any > > problem. For this purpose, pageset_update() is implemented and do some > > memory synchronization. But, it turns out to be wrong when I implemented > > new feature using this. There is no corresponding smp_rmb() in read-side > > Out of curiosity, what new feature are you implementing?
I mean just zone_pcp_disable() and zone_pcp_enable(). :) > IIRC, pageset_update() is used to update high and batch which can be changed > during: > > system boot > sysfs > memory hot-plug > > So it seems to me that the latter two would have the problems you described > here. Yes, I think so. But I'm not sure, because I didn't look at it in detail. :) Thanks. -- 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/
