Drivers: hv: vmbus: On the read path cleanup the logic to interrupt the host

Signal the host when we determine the host is to be signaled -
on th read path. The currrent code determines the need to signal in the
ringbuffer code and actually issues the signal elsewhere. This can result
in the host viewing this interrupt as spurious since the host may also
poll the channel. Make the necessary adjustments.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 8 insertions, 14 deletions

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 8a8148f7b842..5fb4c6d9209b 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -879,16 +879,9 @@ __vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
                    u32 bufferlen, u32 *buffer_actual_len, u64 *requestid,
                    bool raw)
 {
-        int ret;
-        bool signal = false;
-
-        ret = hv_ringbuffer_read(&channel->inbound, buffer, bufferlen,
-                                 buffer_actual_len, requestid, &signal, raw);
+        return hv_ringbuffer_read(channel, buffer, bufferlen,
+                                  buffer_actual_len, requestid, raw);
 
-        if (signal)
-                vmbus_setevent(channel);
-
-        return ret;
 }
 
 int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 2d42ebe2af6c..0675b395ce5c 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -532,9 +532,9 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
                     u32 kv_count, bool lock,
                     bool kick_q);
 
-int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
+int hv_ringbuffer_read(struct vmbus_channel *channel,
                        void *buffer, u32 buflen, u32 *buffer_actual_len,
-                       u64 *requestid, bool *signal, bool raw);
+                       u64 *requestid, bool raw);
 
 void hv_ringbuffer_get_debuginfo(struct hv_ring_buffer_info *ring_info,
                             struct hv_ring_buffer_debug_info *debug_info);
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 4af71306d0ff..cd49cb17eb7f 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -353,9 +353,9 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
         return 0;
 }
 
-int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
+int hv_ringbuffer_read(struct vmbus_channel *channel,
                        void *buffer, u32 buflen, u32 *buffer_actual_len,
-                       u64 *requestid, bool *signal, bool raw)
+                       u64 *requestid, bool raw)
 {
         u32 bytes_avail_toread;
         u32 next_read_location = 0;
@@ -364,6 +364,7 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
         u32 offset;
         u32 packetlen;
         int ret = 0;
+        struct hv_ring_buffer_info *inring_info = &channel->inbound;
 
         if (buflen <= 0)
                 return -EINVAL;
@@ -421,7 +422,7 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
         /* Update the read index */
         hv_set_next_read_location(inring_info, next_read_location);
 
-        *signal = hv_need_to_signal_on_read(inring_info);
+        hv_signal_on_read(channel);
 
         return ret;
 }