| Message ID | 20140204165819.GA28066@aepfle.de |
|---|---|
| State | New |
| Headers | show |
On Tue, 4 Feb 2014, Olaf Hering wrote: > On Tue, Feb 04, Olaf Hering wrote: > > > On Tue, Feb 04, Kevin Wolf wrote: > > > > > Now you call bdrv_acct_done() in the callback without having a matching > > > bdrv_acct_start(). You need to make it conditional in the callback. > > > Stefano, > > Is ioreq_runio_qemu_aio symetric in this regard anyway? In case of > > BLKIF_OP_WRITE|BLKIF_OP_FLUSH_DISKCACHE and no ioreq->req.nr_segments > > then qemu_aio_complete is called anyway. Will qemu_aio_complete get down > > to the bdrv_acct_done call at all in this case? Right, you spotted a bug there: if !ioreq->req.nr_segments, qemu_aio_complete is called without bdrv_acct_start being called first. > What I have in mind is something like the (not compile tested) change below. > > diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c > index e74efc7..99d36b8 100644 > --- a/hw/block/xen_disk.c > +++ b/hw/block/xen_disk.c > @@ -486,7 +486,16 @@ static void qemu_aio_complete(void *opaque, int ret) > ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY; > ioreq_unmap(ioreq); > ioreq_finish(ioreq); > - bdrv_acct_done(ioreq->blkdev->bs, &ioreq->acct); > + switch (ioreq->req.operation) { > + case BLKIF_OP_DISCARD: > + break; > + case BLKIF_OP_WRITE: > + case BLKIF_OP_FLUSH_DISKCACHE: What about BLKIF_OP_READ? > + if (!ioreq->req.nr_segments) { > + break; > + } > + bdrv_acct_done(ioreq->blkdev->bs, &ioreq->acct); > + } > qemu_bh_schedule(ioreq->blkdev->bh); > } > >
diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c index e74efc7..99d36b8 100644 --- a/hw/block/xen_disk.c +++ b/hw/block/xen_disk.c @@ -486,7 +486,16 @@ static void qemu_aio_complete(void *opaque, int ret) ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY; ioreq_unmap(ioreq); ioreq_finish(ioreq); - bdrv_acct_done(ioreq->blkdev->bs, &ioreq->acct); + switch (ioreq->req.operation) { + case BLKIF_OP_DISCARD: + break; + case BLKIF_OP_WRITE: + case BLKIF_OP_FLUSH_DISKCACHE: + if (!ioreq->req.nr_segments) { + break; + } + bdrv_acct_done(ioreq->blkdev->bs, &ioreq->acct); + } qemu_bh_schedule(ioreq->blkdev->bh); }