From 6571b2dab4eb6c7061160490db984dbc01e5626d Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Fri, 15 Mar 2013 12:25:40 -0700 Subject: [PATCH] Drivers: hv: balloon: Execute balloon inflation in a separate context Execute the balloon inflation operation in a separate work context. This allows us to decouple the pressure reporting activity from the ballooning activity. Testing has shown that this decoupling makes the guest more reponsive. Signed-off-by: K. Y. Srinivasan Reviewed-by: Haiyang Zhang Signed-off-by: Greg Kroah-Hartman --- drivers/hv/hv_balloon.c | 34 ++++++++++++++++++++++++---------- 1 file changed, 24 insertions(+), 10 deletions(-) diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 7fb72dd05ba2..8dc406ccf10f 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -412,6 +412,11 @@ struct dm_info_msg { * End protocol definitions. */ +struct balloon_state { + __u32 num_pages; + struct work_struct wrk; +}; + static bool hot_add; static bool do_hot_add; /* @@ -459,7 +464,12 @@ struct hv_dynmem_device { unsigned int num_pages_ballooned; /* - * This thread handles both balloon/hot-add + * State to manage the ballooning (up) operation. + */ + struct balloon_state balloon_wrk; + + /* + * This thread handles hot-add * requests from the host as well as notifying * the host with regards to memory pressure in * the guest. @@ -657,9 +667,9 @@ static int alloc_balloon_pages(struct hv_dynmem_device *dm, int num_pages, -static void balloon_up(struct hv_dynmem_device *dm, struct dm_balloon *req) +static void balloon_up(struct work_struct *dummy) { - int num_pages = req->num_pages; + int num_pages = dm_device.balloon_wrk.num_pages; int num_ballooned = 0; struct dm_balloon_response *bl_resp; int alloc_unit; @@ -684,14 +694,14 @@ static void balloon_up(struct hv_dynmem_device *dm, struct dm_balloon *req) num_pages -= num_ballooned; - num_ballooned = alloc_balloon_pages(dm, num_pages, + num_ballooned = alloc_balloon_pages(&dm_device, num_pages, bl_resp, alloc_unit, &alloc_error); if ((alloc_error) || (num_ballooned == num_pages)) { bl_resp->more_pages = 0; done = true; - dm->state = DM_INITIALIZED; + dm_device.state = DM_INITIALIZED; } /* @@ -719,7 +729,7 @@ static void balloon_up(struct hv_dynmem_device *dm, struct dm_balloon *req) pr_info("Balloon response failed\n"); for (i = 0; i < bl_resp->range_count; i++) - free_balloon_pages(dm, + free_balloon_pages(&dm_device, &bl_resp->range_array[i]); done = true; @@ -775,9 +785,6 @@ static int dm_thread_func(void *dm_dev) scan_start = jiffies; switch (dm->state) { - case DM_BALLOON_UP: - balloon_up(dm, (struct dm_balloon *)recv_buffer); - break; case DM_HOT_ADD: hot_add_req(dm, (struct dm_hot_add *)recv_buffer); @@ -861,6 +868,7 @@ static void balloon_onchannelcallback(void *context) struct dm_message *dm_msg; struct dm_header *dm_hdr; struct hv_dynmem_device *dm = hv_get_drvdata(dev); + struct dm_balloon *bal_msg; memset(recv_buffer, 0, sizeof(recv_buffer)); vmbus_recvpacket(dev->channel, recv_buffer, @@ -882,8 +890,12 @@ static void balloon_onchannelcallback(void *context) break; case DM_BALLOON_REQUEST: + if (dm->state == DM_BALLOON_UP) + pr_warn("Currently ballooning\n"); + bal_msg = (struct dm_balloon *)recv_buffer; dm->state = DM_BALLOON_UP; - complete(&dm->config_event); + dm_device.balloon_wrk.num_pages = bal_msg->num_pages; + schedule_work(&dm_device.balloon_wrk.wrk); break; case DM_UNBALLOON_REQUEST: @@ -937,6 +949,7 @@ static int balloon_probe(struct hv_device *dev, dm_device.next_version = DYNMEM_PROTOCOL_VERSION_WIN7; init_completion(&dm_device.host_event); init_completion(&dm_device.config_event); + INIT_WORK(&dm_device.balloon_wrk.wrk, balloon_up); dm_device.thread = kthread_run(dm_thread_func, &dm_device, "hv_balloon"); @@ -1048,6 +1061,7 @@ static int balloon_remove(struct hv_device *dev) if (dm->num_pages_ballooned != 0) pr_warn("Ballooned pages: %d\n", dm->num_pages_ballooned); + cancel_work_sync(&dm->balloon_wrk.wrk); vmbus_close(dev->channel); kthread_stop(dm->thread); kfree(send_buffer); -- 2.30.2