Check the archives, I replied to this days ago. But since I'm taking the
subject up anyway, let me expand on it a bit further.
Not using plugging is gone, blk_queue_pluggable has been removed from
the current 2.4.4-pre series if you check that. The main reason for
doing this, is that there are generally no reasons for _not_ using
plugging in the 2.4 series kernels. In 2.2 and previous, not using the
builtin plugging was generally done to disable request merging. In 2.4,
the queues have good control over what happens there with the
back/front/request merging functions -- so drivers can just use that.
Besides, the above hunk was removed because it is wrong. For devices
using plugging, we would re-call the request_fn while the device was
already active and serving requests. Not only is this a performance hit
we don't need to take, it also gave problems on some drivers.
-- Jens Axboe- 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/