trace: trace bdrv_open_common()

bdrv_open_common() is a useful point to trace since it reveals the
filename and block driver for a given BlockDriverState.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>

block.c

@@ -475,6 +475,8 @@ static int bdrv_open_common(BlockDriverState *bs, const char *filename,
 
     assert(drv != NULL);
 
+    trace_bdrv_open_common(bs, filename, flags, drv->format_name);
+
     bs->file = NULL;
     bs->total_sectors = 0;
     bs->encrypted = 0;

trace-events

@@ -56,6 +56,7 @@ virtio_console_chr_read(unsigned int port, int size) "port %u, size %d"
 virtio_console_chr_event(unsigned int port, int event) "port %u, event %d"
 
 # block.c
+bdrv_open_common(void *bs, const char *filename, int flags, const char *format_name) "bs %p filename \"%s\" flags %#x format_name \"%s\""
 multiwrite_cb(void *mcb, int ret) "mcb %p ret %d"
 bdrv_aio_multiwrite(void *mcb, int num_callbacks, int num_reqs) "mcb %p num_callbacks %d num_reqs %d"
 bdrv_aio_multiwrite_earlyfail(void *mcb) "mcb %p"