AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

Drivers: hv: vmbus: Fix a siganlling host signalling issue

Browse Source 
Handle the case when the write to the ringbuffer fails. In this case,
unconditionally signal the host. Since we may have deferred signalling
the host based on the kick_q parameter, signalling the host
unconditionally in this case deals with the issue.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
K. Y. Srinivasan 2015-03-18 12:29:30 -07:00 committed by Greg Kroah-Hartman
parent b3a19b36ad
commit 5f5cc81733
1 changed files with 26 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
drivers/hv/channel.c
View File

@ -611,7 +611,19 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
if ((ret == 0) && kick_q && signal)
/*
* Signalling the host is conditional on many factors:
* 1. The ring state changed from being empty to non-empty.
* This is tracked by the variable "signal".
* 2. The variable kick_q tracks if more data will be placed
* on the ring. We will not signal if more data is
* to be placed.
*
* If we cannot write to the ring-buffer; signal the host
* even if we may not have written anything. This is a rare
* enough condition that it should not matter.
*/
if (((ret == 0) && kick_q && signal) || (ret))
vmbus_setevent(channel);
return ret;
@ -702,7 +714,19 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
if ((ret == 0) && kick_q && signal)
/*
* Signalling the host is conditional on many factors:
* 1. The ring state changed from being empty to non-empty.
* This is tracked by the variable "signal".
* 2. The variable kick_q tracks if more data will be placed
* on the ring. We will not signal if more data is
* to be placed.
*
* If we cannot write to the ring-buffer; signal the host
* even if we may not have written anything. This is a rare
* enough condition that it should not matter.
*/
if (((ret == 0) && kick_q && signal) || (ret))
vmbus_setevent(channel);
return ret;