aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/hv/ring_buffer.c
diff options
context:
space:
mode:
authorHaiyang Zhang <haiyangz@microsoft.com>2012-03-27 13:20:45 +0000
committerDavid S. Miller <davem@davemloft.net>2012-04-03 17:47:15 -0400
commit33be96e47cc27f2f1a753a0707b02a73df8c8d46 (patch)
tree2b0361f4d39a14e2ddd0d23e66656e6174b3cb71 /drivers/hv/ring_buffer.c
parentede7193d4fdca98178240500d8684dbc139ca26f (diff)
net/hyperv: Add flow control based on hi/low watermark
In the existing code, we only stop queue when the ringbuffer is full, so the current packet has to be dropped or retried from upper layer. This patch stops the tx queue when available ringbuffer is below the low watermark. So the ringbuffer still has small amount of space available for the current packet. This will reduce the overhead of retries on sending. Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/hv/ring_buffer.c')
-rw-r--r--drivers/hv/ring_buffer.c31
1 files changed, 0 insertions, 31 deletions
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 8af25a097d75..7233c88f01b8 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -30,37 +30,6 @@
#include "hyperv_vmbus.h"
-/* #defines */
-
-
-/* Amount of space to write to */
-#define BYTES_AVAIL_TO_WRITE(r, w, z) \
- ((w) >= (r)) ? ((z) - ((w) - (r))) : ((r) - (w))
-
-
-/*
- *
- * hv_get_ringbuffer_availbytes()
- *
- * Get number of bytes available to read and to write to
- * for the specified ring buffer
- */
-static inline void
-hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi,
- u32 *read, u32 *write)
-{
- u32 read_loc, write_loc;
-
- smp_read_barrier_depends();
-
- /* Capture the read/write indices before they changed */
- read_loc = rbi->ring_buffer->read_index;
- write_loc = rbi->ring_buffer->write_index;
-
- *write = BYTES_AVAIL_TO_WRITE(read_loc, write_loc, rbi->ring_datasize);
- *read = rbi->ring_datasize - *write;
-}
-
/*
* hv_get_next_write_location()
*

Privacy Policy