When the hvsock channel's outbound ringbuffer is full (i.e., hv_ringbuffer_write() returns -EAGAIN), we should avoid the unnecessary signaling the host. Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> --- drivers/hv/channel.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 1161d68..3f04533 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -659,6 +659,9 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer, * 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. + * NOTE: in this case, the hvsock channel is an exception, because + * it looks the host side's hvsock implementation has a throttling + * mechanism which can hurt the performance otherwise. */ if (channel->signal_policy) @@ -666,7 +669,8 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer, else kick_q = true; - if (((ret == 0) && kick_q && signal) || (ret)) + if (((ret == 0) && kick_q && signal) || + (ret && !is_hvsock_channel(channel))) vmbus_setevent(channel); return ret; -- 2.1.0 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
