Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0487426f authored by Stephen Hemminger's avatar Stephen Hemminger Committed by David S. Miller
Browse files

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: default avatarStephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f5a22550

drivers/hv/ring_buffer.c

+23 −0
Original line number Diff line number Diff line
@@ -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)

include/linux/hyperv.h

+0 −22
Original line number Diff line number Diff line
@@ -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)

{