It is useful to understand why an I/O request was failed. Add trace
events for the error paths in bdrv_aio_readv() and bdrv_aio_writev().
Signed-off-by: Stefan Hajnoczi <stefa...@linux.vnet.ibm.com>
---
block.c | 24 +++++++++++++++++++-----
trace-events | 7 +++++++
2 files changed, 26 insertions(+), 5 deletions(-)
diff --git a/block.c b/block.c
index 4da35be..816edd6 100644
--- a/block.c
+++ b/block.c
@@ -2129,10 +2129,14 @@ BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs,
int64_t sector_num,
trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque);
- if (!drv)
+ if (!drv) {
+ trace_bdrv_aio_readv_null_drv(bs, sector_num, nb_sectors, opaque);
return NULL;
- if (bdrv_check_request(bs, sector_num, nb_sectors))
+ }
+ if (bdrv_check_request(bs, sector_num, nb_sectors)) {
+ trace_bdrv_aio_readv_out_of_range(bs, sector_num, nb_sectors, opaque);
return NULL;
+ }
ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
cb, opaque);
@@ -2141,6 +2145,8 @@ BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs,
int64_t sector_num,
/* Update stats even though technically transfer has not happened. */
bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
bs->rd_ops ++;
+ } else {
+ trace_bdrv_aio_readv_failed(bs, sector_num, nb_sectors, opaque);
}
return ret;
@@ -2192,12 +2198,18 @@ BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs,
int64_t sector_num,
trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque);
- if (!drv)
+ if (!drv) {
+ trace_bdrv_aio_writev_null_drv(bs, sector_num, nb_sectors, opaque);
return NULL;
- if (bs->read_only)
+ }
+ if (bs->read_only) {
+ trace_bdrv_aio_writev_read_only(bs, sector_num, nb_sectors, opaque);
return NULL;
- if (bdrv_check_request(bs, sector_num, nb_sectors))
+ }
+ if (bdrv_check_request(bs, sector_num, nb_sectors)) {
+ trace_bdrv_aio_writev_out_of_range(bs, sector_num, nb_sectors, opaque);
return NULL;
+ }
if (bs->dirty_bitmap) {
blk_cb_data = blk_dirty_cb_alloc(bs, sector_num, nb_sectors, cb,
@@ -2216,6 +2228,8 @@ BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs,
int64_t sector_num,
if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
bs->wr_highest_sector = sector_num + nb_sectors - 1;
}
+ } else {
+ trace_bdrv_aio_writev_failed(bs, sector_num, nb_sectors, opaque);
}
return ret;
diff --git a/trace-events b/trace-events
index 10faa07..3518254 100644
--- a/trace-events
+++ b/trace-events
@@ -53,7 +53,14 @@ disable bdrv_aio_multiwrite_earlyfail(void *mcb) "mcb %p"
disable bdrv_aio_multiwrite_latefail(void *mcb, int i) "mcb %p i %d"
disable bdrv_aio_flush(void *bs, void *opaque) "bs %p opaque %p"
disable bdrv_aio_readv(void *bs, int64_t sector_num, int nb_sectors, void
*opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
+disable bdrv_aio_readv_null_drv(void *bs, int64_t sector_num, int nb_sectors,
void *opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
+disable bdrv_aio_readv_out_of_range(void *bs, int64_t sector_num, int
nb_sectors, void *opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
+disable bdrv_aio_readv_failed(void *bs, int64_t sector_num, int nb_sectors,
void *opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
disable bdrv_aio_writev(void *bs, int64_t sector_num, int nb_sectors, void
*opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
+disable bdrv_aio_writev_null_drv(void *bs, int64_t sector_num, int nb_sectors,
void *opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
+disable bdrv_aio_writev_read_only(void *bs, int64_t sector_num, int
nb_sectors, void *opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
+disable bdrv_aio_writev_out_of_range(void *bs, int64_t sector_num, int
nb_sectors, void *opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
+disable bdrv_aio_writev_failed(void *bs, int64_t sector_num, int nb_sectors,
void *opaque) "bs %p sector_num %"PRId64" nb_sectors %d opaque %p"
disable bdrv_set_locked(void *bs, int locked) "bs %p locked %d"
# hw/virtio-blk.c
--
1.7.5.3
