Drivers: hv: balloon: Execute hot-add code in a separate context

Execute the hot-add operation in a separate work context.
This allows us to decouple the pressure reporting activity from the
"hot-add" activity. Testing has shown that this makes the guest more
responsive to hot add requests.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
K. Y. Srinivasan 2013-03-15 12:25:41 -07:00 коммит произвёл Greg Kroah-Hartman
Родитель 6571b2dab4
Коммит c51af826cf
1 изменённых файлов: 23 добавлений и 18 удалений

Просмотреть файл

@ -417,6 +417,11 @@ struct balloon_state {
struct work_struct wrk;
};
struct hot_add_wrk {
union dm_mem_page_range ha_page_range;
struct work_struct wrk;
};
static bool hot_add;
static bool do_hot_add;
/*
@ -468,6 +473,11 @@ struct hv_dynmem_device {
*/
struct balloon_state balloon_wrk;
/*
* State to execute the "hot-add" operation.
*/
struct hot_add_wrk ha_wrk;
/*
* This thread handles hot-add
* requests from the host as well as notifying
@ -486,7 +496,7 @@ struct hv_dynmem_device {
static struct hv_dynmem_device dm_device;
static void hot_add_req(struct hv_dynmem_device *dm, struct dm_hot_add *msg)
static void hot_add_req(struct work_struct *dummy)
{
struct dm_hot_add_response resp;
@ -509,8 +519,8 @@ static void hot_add_req(struct hv_dynmem_device *dm, struct dm_hot_add *msg)
resp.page_count = 0;
resp.result = 0;
dm->state = DM_INITIALIZED;
vmbus_sendpacket(dm->dev->channel, &resp,
dm_device.state = DM_INITIALIZED;
vmbus_sendpacket(dm_device.dev->channel, &resp,
sizeof(struct dm_hot_add_response),
(unsigned long)NULL,
VM_PKT_DATA_INBAND, 0);
@ -771,7 +781,6 @@ static int dm_thread_func(void *dm_dev)
{
struct hv_dynmem_device *dm = dm_dev;
int t;
unsigned long scan_start;
while (!kthread_should_stop()) {
t = wait_for_completion_timeout(&dm_device.config_event, 1*HZ);
@ -783,19 +792,6 @@ static int dm_thread_func(void *dm_dev)
if (t == 0)
post_status(dm);
scan_start = jiffies;
switch (dm->state) {
case DM_HOT_ADD:
hot_add_req(dm, (struct dm_hot_add *)recv_buffer);
break;
default:
break;
}
if (!time_in_range(jiffies, scan_start, scan_start + HZ))
post_status(dm);
}
return 0;
@ -869,6 +865,8 @@ static void balloon_onchannelcallback(void *context)
struct dm_header *dm_hdr;
struct hv_dynmem_device *dm = hv_get_drvdata(dev);
struct dm_balloon *bal_msg;
struct dm_hot_add *ha_msg;
union dm_mem_page_range *ha_pg_range;
memset(recv_buffer, 0, sizeof(recv_buffer));
vmbus_recvpacket(dev->channel, recv_buffer,
@ -905,8 +903,13 @@ static void balloon_onchannelcallback(void *context)
break;
case DM_MEM_HOT_ADD_REQUEST:
if (dm->state == DM_HOT_ADD)
pr_warn("Currently hot-adding\n");
dm->state = DM_HOT_ADD;
complete(&dm->config_event);
ha_msg = (struct dm_hot_add *)recv_buffer;
ha_pg_range = &ha_msg->range;
dm_device.ha_wrk.ha_page_range = *ha_pg_range;
schedule_work(&dm_device.ha_wrk.wrk);
break;
case DM_INFO_MESSAGE:
@ -950,6 +953,7 @@ static int balloon_probe(struct hv_device *dev,
init_completion(&dm_device.host_event);
init_completion(&dm_device.config_event);
INIT_WORK(&dm_device.balloon_wrk.wrk, balloon_up);
INIT_WORK(&dm_device.ha_wrk.wrk, hot_add_req);
dm_device.thread =
kthread_run(dm_thread_func, &dm_device, "hv_balloon");
@ -1062,6 +1066,7 @@ static int balloon_remove(struct hv_device *dev)
pr_warn("Ballooned pages: %d\n", dm->num_pages_ballooned);
cancel_work_sync(&dm->balloon_wrk.wrk);
cancel_work_sync(&dm->ha_wrk.wrk);
vmbus_close(dev->channel);
kthread_stop(dm->thread);
kfree(send_buffer);