| Message ID | 1387038700-9264-1-git-send-email-pl@kamp.de |
|---|---|
| State | New |
| Headers | show |
Il 14/12/2013 17:31, Peter Lieven ha scritto: > this fixes a potential segfault and performance regression. > > If the coroutine is reentered directly in the iscsi_co_generic_cb > iscsi_process_{read,write} are interrupted and reentered any > time later. One the one hand this could happen after an iscsi_close > where the iscsi context is already gone (segfault). On the > other hand this limits the number of processed callbacks > in each aio_dispatch to one (potential performance regression). > > Cc: qemu-stable@nongnu.org > Signed-off-by: Peter Lieven <pl@kamp.de> > --- > block/iscsi.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/block/iscsi.c b/block/iscsi.c > index fa69408..b0e6eea 100644 > --- a/block/iscsi.c > +++ b/block/iscsi.c > @@ -68,6 +68,7 @@ typedef struct IscsiTask { > int do_retry; > struct scsi_task *task; > Coroutine *co; > + QEMUBH *bh; > } IscsiTask; > > typedef struct IscsiAIOCB { > @@ -123,6 +124,13 @@ iscsi_schedule_bh(IscsiAIOCB *acb) > qemu_bh_schedule(acb->bh); > } > > +static void iscsi_co_generic_bh_cb(void *opaque) > +{ > + struct IscsiTask *iTask = opaque; > + qemu_bh_delete(iTask->bh); > + qemu_coroutine_enter(iTask->co, NULL); > +} > + > static void > iscsi_co_generic_cb(struct iscsi_context *iscsi, int status, > void *command_data, void *opaque) > @@ -147,7 +155,8 @@ iscsi_co_generic_cb(struct iscsi_context *iscsi, int status, > > out: > if (iTask->co) { > - qemu_coroutine_enter(iTask->co, NULL); > + iTask->bh = qemu_bh_new(iscsi_co_generic_bh_cb, iTask); > + qemu_bh_schedule(iTask->bh); > } > } > > Applied to scsi-next branch, thanks. Paolo
diff --git a/block/iscsi.c b/block/iscsi.c index fa69408..b0e6eea 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -68,6 +68,7 @@ typedef struct IscsiTask { int do_retry; struct scsi_task *task; Coroutine *co; + QEMUBH *bh; } IscsiTask; typedef struct IscsiAIOCB { @@ -123,6 +124,13 @@ iscsi_schedule_bh(IscsiAIOCB *acb) qemu_bh_schedule(acb->bh); } +static void iscsi_co_generic_bh_cb(void *opaque) +{ + struct IscsiTask *iTask = opaque; + qemu_bh_delete(iTask->bh); + qemu_coroutine_enter(iTask->co, NULL); +} + static void iscsi_co_generic_cb(struct iscsi_context *iscsi, int status, void *command_data, void *opaque) @@ -147,7 +155,8 @@ iscsi_co_generic_cb(struct iscsi_context *iscsi, int status, out: if (iTask->co) { - qemu_coroutine_enter(iTask->co, NULL); + iTask->bh = qemu_bh_new(iscsi_co_generic_bh_cb, iTask); + qemu_bh_schedule(iTask->bh); } }
this fixes a potential segfault and performance regression. If the coroutine is reentered directly in the iscsi_co_generic_cb iscsi_process_{read,write} are interrupted and reentered any time later. One the one hand this could happen after an iscsi_close where the iscsi context is already gone (segfault). On the other hand this limits the number of processed callbacks in each aio_dispatch to one (potential performance regression). Cc: qemu-stable@nongnu.org Signed-off-by: Peter Lieven <pl@kamp.de> --- block/iscsi.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)