From: Jason Wang Date: Tue, 18 Jun 2013 05:04:23 +0000 (+0800) Subject: drivers: hv: switch to use mb() instead of smp_mb() X-Git-Tag: v3.2.49~56 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e4af376d04b03ff3ab2f27701bb183da6ee2aaff;p=people%2Fms%2Flinux.git drivers: hv: switch to use mb() instead of smp_mb() commit 35848f68b07df3f917cb13fc3c134718669f569b upstream. 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 Cc: Haiyang Zhang Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: - Drop changes to functions that don't exist here - hv_ringbuffer_write() has only a write memory barrier] Signed-off-by: Ben Hutchings --- diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 8af25a097d75..810658e8211a 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -383,7 +383,7 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info, sizeof(u64)); /* Make sure we flush all writes before updating the writeIndex */ - smp_wmb(); + wmb(); /* Now, update the write location */ hv_set_next_write_location(outring_info, next_write_location); diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index d2d0a2a9676d..44442d5e5a93 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -466,7 +466,7 @@ static void vmbus_on_msg_dpc(unsigned long data) * will not deliver any more messages since there is * no empty slot */ - smp_mb(); + mb(); if (msg->header.message_flags.msg_pending) { /*