Re: [RFC v8 PATCH 08/20] memory-hotplug: remove /sys/firmware/memmap/X sysfs

At 09/05/2012 07:16 AM, Andrew Morton Wrote:

On Mon, 03 Sep 2012 13:51:10 +0800
Wen Congyang [off-list ref] wrote:

quoted

quoted

quoted

+static void release_firmware_map_entry(struct kobject *kobj)
+{
+	struct firmware_map_entry *entry = to_memmap_entry(kobj);
+	struct page *page;
+
+	page = virt_to_page(entry);
+	if (PageSlab(page) || PageCompound(page))

That PageCompound() test looks rather odd.  Why is this done?

Liu Jiang and Christoph Lameter discussed how to find slab page
in this mail:
https://lkml.org/lkml/2012/7/6/333.

Well, please add a code comment to release_firmware_map_entry() which
fully explains these things.

I see that Christoph and I agree: "It would be cleaner if memory
hotplug had an indicator which allocation mechanism was used and would
use the corresponding free action".  You didn't respond to this
suggestion when he made it, nor when I made it.  What are your thoughts
on this?

Hmm, I think it is better to use an indicator which allocation mechanism was
used. I will do it in the next version.

Thanks
Wen Congyang