@@ -407,10 +407,10 @@ EXPORT_SYMBOL_GPL(__hv_pkt_iter_next);
void hv_pkt_iter_close(struct vmbus_channel *channel)
{
struct hv_ring_buffer_info *rbi = &channel->inbound;
- u32 cached_write_sz, cur_write_sz, pending_sz;
+ u32 orig_write_sz;
/* Available space before read_index update */
- cached_write_sz = hv_get_bytes_to_write(rbi);
+ orig_write_sz = hv_get_bytes_to_write(rbi);
/*
* Make sure all reads are done before we update the read index since
@@ -422,6 +422,10 @@ void hv_pkt_iter_close(struct vmbus_channel *channel)
/* Update the position where ring buffer has been read from */
rbi->ring_buffer->read_index = rbi->priv_read_index;
+ /* If more data is available then no need to signal */
+ if (hv_get_bytes_to_read(rbi))
+ return;
+
/*
* If the reading of the pend_sz were to be reordered and read
* before we commit the new read index.
@@ -431,22 +435,18 @@ void hv_pkt_iter_close(struct vmbus_channel *channel)
virt_wmb();
if (rbi->ring_buffer->feature_bits.feat_pending_send_sz) {
- pending_sz = READ_ONCE(rbi->ring_buffer->pending_send_sz);
-
- /* If the other end is not blocked on write don't bother. */
- if (pending_sz == 0)
- return;
-
- /* If pending write will not fit, don't give false hope. */
- cur_write_sz = hv_get_bytes_to_write(rbi);
- if (cur_write_sz < pending_sz)
- return;
+ u32 pending_sz = READ_ONCE(rbi->ring_buffer->pending_send_sz);
/*
* If there was space before we began iteration, then
- * host was not blocked.
+ * host was not blocked. Also handles the case where
+ * pending_sz is zero because host has nothing pending.
*/
- if (cached_write_sz >= pending_sz)
+ if (orig_write_sz > pending_sz)
+ return;
+
+ /* If pending write will not fit, don't give false hope. */
+ if (hv_get_bytes_to_write(rbi) < pending_sz)
return;
}
BugLink: http://bugs.launchpad.net/bugs/1748662 This reverts commit 9ea3e22cb96dcca0d12213c12b503253ceb0e798. Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri@canonical.com> --- drivers/hv/ring_buffer.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-)