diff options
authorK. Y. Srinivasan <kys@microsoft.com>2014-07-07 16:34:24 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-07-09 14:34:35 -0700
commitaffb1aff300ddee54df307812b38f166e8a865ef (patch)
parenta497c3ba1d97fc69c1e78e7b96435ba8c2cb42ee (diff)
Drivers: hv: vmbus: Fix a bug in the channel callback dispatch code
Starting with Win8, we have implemented several optimizations to improve the scalability and performance of the VMBUS transport between the Host and the Guest. Some of the non-performance critical services cannot leverage these optimization since they only read and process one message at a time. Make adjustments to the callback dispatch code to account for the way non-performance critical drivers handle reading of the channel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index e84f4526eb3..ae22e3c1fc4 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -339,9 +339,13 @@ static void process_chn_event(u32 relid)
do {
- hv_begin_read(&channel->inbound);
+ if (read_state)
+ hv_begin_read(&channel->inbound);
- bytes_to_read = hv_end_read(&channel->inbound);
+ if (read_state)
+ bytes_to_read = hv_end_read(&channel->inbound);
+ else
+ bytes_to_read = 0;
} while (read_state && (bytes_to_read != 0));
} else {
pr_err("no channel callback for relid - %u\n", relid);