diff options
| author | Jason Wang <jasowang@redhat.com> | 2013-06-18 13:04:23 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-06-18 11:14:18 -0700 |
| commit | 35848f68b07df3f917cb13fc3c134718669f569b (patch) | |
| tree | 6d098733bc0126ad5e133ff23d26caba0ed919e8 /drivers/hv/ring_buffer.c | |
| parent | 36dd68319c7b56a76ed450b0e470067b5d74b9b2 (diff) | |
| download | linux-35848f68b07df3f917cb13fc3c134718669f569b.tar.bz2 | |
drivers: hv: switch to use mb() instead of smp_mb()
Even if guest were compiled without SMP support, it could not assume that host
wasn't. So switch to use mb() instead of smp_mb() to force memory barriers for
UP guest.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hv/ring_buffer.c')
| -rw-r--r-- | drivers/hv/ring_buffer.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index d6fbb5772b8d..791f45dfc85d 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -32,7 +32,7 @@ void hv_begin_read(struct hv_ring_buffer_info *rbi) { rbi->ring_buffer->interrupt_mask = 1; - smp_mb(); + mb(); } u32 hv_end_read(struct hv_ring_buffer_info *rbi) @@ -41,7 +41,7 @@ u32 hv_end_read(struct hv_ring_buffer_info *rbi) u32 write; rbi->ring_buffer->interrupt_mask = 0; - smp_mb(); + mb(); /* * Now check to see if the ring buffer is still empty. @@ -71,7 +71,7 @@ u32 hv_end_read(struct hv_ring_buffer_info *rbi) static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi) { - smp_mb(); + mb(); if (rbi->ring_buffer->interrupt_mask) return false; @@ -442,7 +442,7 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info, sizeof(u64)); /* Issue a full memory barrier before updating the write index */ - smp_mb(); + mb(); /* Now, update the write location */ hv_set_next_write_location(outring_info, next_write_location); @@ -549,7 +549,7 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer, /* Make sure all reads are done before we update the read index since */ /* the writer may start writing to the read area once the read index */ /*is updated */ - smp_mb(); + mb(); /* Update the read index */ hv_set_next_read_location(inring_info, next_read_location); |