vmbus: make hv_get_ringbuffer_availbytes local

The last use of hv_get_ringbuffer_availbytes in drivers is now
gone. Only used by the debug info routine so make it static. Also, add
READ_ONCE() to avoid any possible issues with potentially volatile
index values.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger 2017-12-01 11:01:49 -08:00 committed by David S. Miller
parent f5a2255010
commit 0487426fed
2 changed files with 23 additions and 22 deletions

View File

@ -140,6 +140,29 @@ static u32 hv_copyto_ringbuffer(
return start_write_offset;
}
/*
*
* hv_get_ringbuffer_availbytes()
*
* Get number of bytes available to read and to write to
* for the specified ring buffer
*/
static void
hv_get_ringbuffer_availbytes(const struct hv_ring_buffer_info *rbi,
u32 *read, u32 *write)
{
u32 read_loc, write_loc, dsize;
/* Capture the read/write indices before they changed */
read_loc = READ_ONCE(rbi->ring_buffer->read_index);
write_loc = READ_ONCE(rbi->ring_buffer->write_index);
dsize = rbi->ring_datasize;
*write = write_loc >= read_loc ? dsize - (write_loc - read_loc) :
read_loc - write_loc;
*read = dsize - *write;
}
/* Get various debug metrics for the specified ring buffer. */
void hv_ringbuffer_get_debuginfo(const struct hv_ring_buffer_info *ring_info,
struct hv_ring_buffer_debug_info *debug_info)

View File

@ -127,28 +127,6 @@ struct hv_ring_buffer_info {
u32 priv_read_index;
};
/*
*
* 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(const struct hv_ring_buffer_info *rbi,
u32 *read, u32 *write)
{
u32 read_loc, write_loc, dsize;
/* Capture the read/write indices before they changed */
read_loc = rbi->ring_buffer->read_index;
write_loc = rbi->ring_buffer->write_index;
dsize = rbi->ring_datasize;
*write = write_loc >= read_loc ? dsize - (write_loc - read_loc) :
read_loc - write_loc;
*read = dsize - *write;
}
static inline u32 hv_get_bytes_to_read(const struct hv_ring_buffer_info *rbi)
{