blkdebug: Add BLKDBG_FLUSH_TO_OS/DISK events

Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

block.c

@@ -3186,13 +3186,11 @@ int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
 
 void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
 {
-    BlockDriver *drv = bs->drv;
-
-    if (!drv || !drv->bdrv_debug_event) {
+    if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) {
         return;
     }
 
-    drv->bdrv_debug_event(bs, event);
+    bs->drv->bdrv_debug_event(bs, event);
 }
 
 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
@@ -4024,6 +4022,7 @@ int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
     }
 
     /* Write back cached data to the OS even with cache=unsafe */
+    BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS);
     if (bs->drv->bdrv_co_flush_to_os) {
         ret = bs->drv->bdrv_co_flush_to_os(bs);
         if (ret < 0) {
@@ -4036,6 +4035,7 @@ int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
         goto flush_parent;
     }
 
+    BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_DISK);
     if (bs->drv->bdrv_co_flush_to_disk) {
         ret = bs->drv->bdrv_co_flush_to_disk(bs);
     } else if (bs->drv->bdrv_aio_flush) {

block/blkdebug.c

@@ -182,6 +182,9 @@ static const char *event_names[BLKDBG_EVENT_MAX] = {
     [BLKDBG_CLUSTER_ALLOC]                  = "cluster_alloc",
     [BLKDBG_CLUSTER_ALLOC_BYTES]            = "cluster_alloc_bytes",
     [BLKDBG_CLUSTER_FREE]                   = "cluster_free",
+
+    [BLKDBG_FLUSH_TO_OS]                    = "flush_to_os",
+    [BLKDBG_FLUSH_TO_DISK]                  = "flush_to_disk",
 };
 
 static int get_event_by_name(const char *name, BlkDebugEvent *event)

include/block/block.h

@@ -424,6 +424,9 @@ typedef enum {
     BLKDBG_CLUSTER_ALLOC_BYTES,
     BLKDBG_CLUSTER_FREE,
 
+    BLKDBG_FLUSH_TO_OS,
+    BLKDBG_FLUSH_TO_DISK,
+
     BLKDBG_EVENT_MAX,
 } BlkDebugEvent;