Drivers: hv: vmbus: Enable explicit signaling policy for NIC channels
For synthetic NIC channels, enable explicit signaling policy as netvsc wants to
explicitly control when the host is to be signaled.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index e47d37d..9a49505 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -650,7 +650,7 @@
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
ret = hv_ringbuffer_write(&channel->outbound, bufferlist, num_vecs,
- &signal, lock);
+ &signal, lock, channel->signal_policy);
/*
* Signalling the host is conditional on many factors:
@@ -671,11 +671,6 @@
* mechanism which can hurt the performance otherwise.
*/
- if (channel->signal_policy)
- signal = true;
- else
- kick_q = true;
-
if (((ret == 0) && kick_q && signal) ||
(ret && !is_hvsock_channel(channel)))
vmbus_setevent(channel);
@@ -768,7 +763,7 @@
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3,
- &signal, lock);
+ &signal, lock, channel->signal_policy);
/*
* Signalling the host is conditional on many factors:
@@ -786,11 +781,6 @@
* enough condition that it should not matter.
*/
- if (channel->signal_policy)
- signal = true;
- else
- kick_q = true;
-
if (((ret == 0) && kick_q && signal) || (ret))
vmbus_setevent(channel);
@@ -852,7 +842,7 @@
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3,
- &signal, lock);
+ &signal, lock, channel->signal_policy);
if (ret == 0 && signal)
vmbus_setevent(channel);
@@ -917,7 +907,7 @@
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3,
- &signal, lock);
+ &signal, lock, channel->signal_policy);
if (ret == 0 && signal)
vmbus_setevent(channel);
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 8818b92..d8b64ba 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -426,6 +426,8 @@
}
dev_type = hv_get_dev_type(&newchannel->offermsg.offer.if_type);
+ if (dev_type == HV_NIC)
+ set_channel_signal_state(newchannel, HV_SIGNAL_POLICY_EXPLICIT);
init_vp_index(newchannel, dev_type);
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index dfa9fac..ddcc348 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -529,7 +529,8 @@
int hv_ringbuffer_write(struct hv_ring_buffer_info *ring_info,
struct kvec *kv_list,
- u32 kv_count, bool *signal, bool lock);
+ u32 kv_count, bool *signal, bool lock,
+ enum hv_signal_policy policy);
int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
void *buffer, u32 buflen, u32 *buffer_actual_len,
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index fe586bf..e3edcae 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -66,12 +66,20 @@
* arrived.
*/
-static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi)
+static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi,
+ enum hv_signal_policy policy)
{
virt_mb();
if (READ_ONCE(rbi->ring_buffer->interrupt_mask))
return false;
+ /*
+ * When the client wants to control signaling,
+ * we only honour the host interrupt mask.
+ */
+ if (policy == HV_SIGNAL_POLICY_EXPLICIT)
+ return true;
+
/* check interrupt_mask before read_index */
virt_rmb();
/*
@@ -264,7 +272,8 @@
/* Write to the ring buffer. */
int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
- struct kvec *kv_list, u32 kv_count, bool *signal, bool lock)
+ struct kvec *kv_list, u32 kv_count, bool *signal, bool lock,
+ enum hv_signal_policy policy)
{
int i = 0;
u32 bytes_avail_towrite;
@@ -326,7 +335,7 @@
if (lock)
spin_unlock_irqrestore(&outring_info->ring_lock, flags);
- *signal = hv_need_to_signal(old_write, outring_info);
+ *signal = hv_need_to_signal(old_write, outring_info, policy);
return 0;
}