Hello, again. On Thu, Feb 07, 2013 at 02:02:27PM -0800, Tejun Heo wrote: > I do like work items pointing back to workers instead of pools, so I > think I'll try that differently.
I tried to convert work->data to point to the last worker and having tried it I'm not too sure about it anymore. * work->data points to cwq while queued which basically is the current pool + target workqueue. Making work->data point to worker off queue makes the two modes further apart, which is a bit uncomfortable. * Also, as it currently stands, we can't remove busy_hash because on-queue work->data can't point to the last worker and thus we need to look up busy_hash before actually executing it. If we're gonna have to keep busy_hash, we might as well use it consistently. * With pending idr changes, idr lookups become very efficient if the ID range is limited. The range currently is 256 which should be enough to cover all the pools in most configurations. The idr lookup essentially becomes if (prefix matches) return hint[offset], so I don't think it would save anything measureable from removing that look up. Replacing the idr + busy_hash lookup with single idr last worker lookup could still be nicer, I think, but probably not by too much. So, I'm not really seeing too much benefit in converting work->data to point to the last worker. If we can remove busy_hash, maybe, but short of that, I think I'm gonna keep things the way they're now. Thanks! -- tejun -- 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/
