Re: [PATCH 1/5] try parent numa_node at first before using default

From: Cornelia Huck
Date: Thu Jul 12 2007 - 11:23:20 EST


On Thu, 12 Jul 2007 13:30:28 +0200,
Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx> wrote:

> So, since figuring the correct DMA device out is done by drivers
> themselves, they usually can figure out the correct NUMA node as well.
> The only precondition is that each DMA device has the correct NUMA node
> set. This is the job of subsystems like PCI, but it may be reasonable
> to have simple and broadly applicable helpers for this in the driver core.
>
> So, _is_ the dev->numa_node = dev->parent.numa_node assumption, if
> implemented in device_add() and device_move(), as simple and as broadly
> applicable as we want driver core's API to be? Perhaps yes.

If making the general assumption that the device will inherit the
numa_node through its parent(s) from the responsible DMA device is
reasonable, then device_move() should certainly update the numa_node
from the new parent. (For special cases, the caller could still call
set_dev_node() itself.)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/