Drivers: hv: hv_balloon: Don't post pressure status from interrupt context

We currently release memory (balloon down) in the interrupt context and we also
post memory status while releasing memory. Rather than posting the status
in the interrupt context, wakeup the status posting thread to post the status.
This will address the inconsistent lock state that Sitsofe Wheeler <sitsofe@gmail.com>
reported:

http://lkml.iu.edu/hypermail/linux/kernel/1411.1/00075.html

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reported-by: Sitsofe Wheeler <sitsofe@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
K. Y. Srinivasan 2015-01-09 23:54:31 -08:00 committed by Greg Kroah-Hartman
parent 22f88475b6
commit ab3de22bb4

View file

@ -1226,7 +1226,7 @@ static void balloon_down(struct hv_dynmem_device *dm,
for (i = 0; i < range_count; i++) {
free_balloon_pages(dm, &range_array[i]);
post_status(&dm_device);
complete(&dm_device.config_event);
}
if (req->more_pages == 1)
@ -1250,19 +1250,16 @@ static void balloon_onchannelcallback(void *context);
static int dm_thread_func(void *dm_dev)
{
struct hv_dynmem_device *dm = dm_dev;
int t;
while (!kthread_should_stop()) {
t = wait_for_completion_interruptible_timeout(
wait_for_completion_interruptible_timeout(
&dm_device.config_event, 1*HZ);
/*
* The host expects us to post information on the memory
* pressure every second.
*/
if (t == 0)
post_status(dm);
reinit_completion(&dm_device.config_event);
post_status(dm);
}
return 0;