[PATCH 6/9] Drivers: hv: ring_buffer: remove stray smp_read_barrier_depends()

K. Y. Srinivasan kys at microsoft.com
Tue Dec 15 03:01:58 UTC 2015


From: Vitaly Kuznetsov <vkuznets at redhat.com>

smp_read_barrier_depends() does nothing on almost all arcitectures
including x86 and having it in the beginning of
hv_get_ringbuffer_availbytes() does not provide any guarantees anyway.

Signed-off-by: Vitaly Kuznetsov <vkuznets at redhat.com>
Signed-off-by: K. Y. Srinivasan <kys at microsoft.com>
---
 include/linux/hyperv.h |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index acd995b..179ff33 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -141,8 +141,6 @@ hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi,
 {
 	u32 read_loc, write_loc, dsize;
 
-	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;
-- 
1.7.4.1



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