net/irda: Use barrier to set task state
authorPeter Hurley <peter@hurleysoftware.com>
Tue, 5 Mar 2013 06:09:06 +0000 (06:09 +0000)
committerDavid S. Miller <davem@davemloft.net>
Wed, 6 Mar 2013 07:47:04 +0000 (02:47 -0500)
commit0b176ce3a7cbfa92eceddf3896f1a504877d974a
treefe3b0e5154f51ba4a8a87dc6bd4dbd00e47270b6
parent2f7c069b96ed7b1f6236f2fa7b0bc06f4f54f2d9
net/irda: Use barrier to set task state

Without a memory and compiler barrier, the task state change
can migrate relative to the condition testing in a blocking loop.
However, the task state change must be visible across all cpus
prior to testing those conditions. Failing to do this can result
in the familiar 'lost wakeup' and this task will hang until killed.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/irda/ircomm/ircomm_tty.c