Commit e3b7df65 authored by ecashin@coraid.com's avatar ecashin@coraid.com Committed by Greg KH

[PATCH] aoe 9/12: add note about the need for deadlock-free sk_buff allocation

add note about the need for deadlock-free sk_buff allocation
Signed-off-by: default avatarEd L. Cashin <ecashin@coraid.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent d098840e
There is a potential for deadlock when allocating a struct sk_buff for
data that needs to be written out to aoe storage. If the data is
being written from a dirty page in order to free that page, and if
there are no other pages available, then deadlock may occur when a
free page is needed for the sk_buff allocation. This situation has
not been observed, but it would be nice to eliminate any potential for
deadlock under memory pressure.
Because ATA over Ethernet is not fragmented by the kernel's IP code,
the destructore member of the struct sk_buff is available to the aoe
driver. By using a mempool for allocating all but the first few
sk_buffs, and by registering a destructor, we should be able to
efficiently allocate sk_buffs without introducing any potential for
deadlock.
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment