| Message ID | 20240124074201.8239-5-philmd@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | hw/accel: Use RCU_READ macros | expand |
On Wed, 24 Jan 2024 09:41, Philippe Mathieu-Daudé <philmd@linaro.org> wrote: >Replace the manual rcu_read_(un)lock calls by the >WITH_RCU_READ_LOCK_GUARD macro (See commit ef46ae67ba >"docs/style: call out the use of GUARD macros"). > >Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> >--- > hw/scsi/virtio-scsi.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > >diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c >index 690aceec45..998227404a 100644 >--- a/hw/scsi/virtio-scsi.c >+++ b/hw/scsi/virtio-scsi.c >@@ -343,14 +343,14 @@ static void virtio_scsi_do_one_tmf_bh(VirtIOSCSIReq *req) > target = req->req.tmf.lun[1]; > qatomic_inc(&s->resetting); > >- rcu_read_lock(); >- QTAILQ_FOREACH_RCU(kid, &s->bus.qbus.children, sibling) { >- SCSIDevice *d1 = SCSI_DEVICE(kid->child); >- if (d1->channel == 0 && d1->id == target) { >- device_cold_reset(&d1->qdev); >+ WITH_RCU_READ_LOCK_GUARD() { >+ QTAILQ_FOREACH_RCU(kid, &s->bus.qbus.children, sibling) { >+ SCSIDevice *d1 = SCSI_DEVICE(kid->child); >+ if (d1->channel == 0 && d1->id == target) { >+ device_cold_reset(&d1->qdev); >+ } > } > } >- rcu_read_unlock(); > > qatomic_dec(&s->resetting); > break; >-- >2.41.0 > Unrelated to your patch: I just noticed in hw/scsi/virtio-scsi.c, s->resetting is used to flag whether the bus is resetting; but there's no check if a resetting is taking place before starting another. Is this single threaded code so it's not necessary? As for the patch: Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
On 24/1/24 10:17, Manos Pitsidianakis wrote: > On Wed, 24 Jan 2024 09:41, Philippe Mathieu-Daudé <philmd@linaro.org> > wrote: >> Replace the manual rcu_read_(un)lock calls by the >> WITH_RCU_READ_LOCK_GUARD macro (See commit ef46ae67ba >> "docs/style: call out the use of GUARD macros"). >> >> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> >> --- >> hw/scsi/virtio-scsi.c | 12 ++++++------ >> 1 file changed, 6 insertions(+), 6 deletions(-) > Unrelated to your patch: I just noticed in hw/scsi/virtio-scsi.c, > s->resetting is used to flag whether the bus is resetting; but there's > no check if a resetting is taking place before starting another. Is this > single threaded code so it's not necessary? No clue about this device, I'll let the maintainers answer you :)
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index 690aceec45..998227404a 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -343,14 +343,14 @@ static void virtio_scsi_do_one_tmf_bh(VirtIOSCSIReq *req) target = req->req.tmf.lun[1]; qatomic_inc(&s->resetting); - rcu_read_lock(); - QTAILQ_FOREACH_RCU(kid, &s->bus.qbus.children, sibling) { - SCSIDevice *d1 = SCSI_DEVICE(kid->child); - if (d1->channel == 0 && d1->id == target) { - device_cold_reset(&d1->qdev); + WITH_RCU_READ_LOCK_GUARD() { + QTAILQ_FOREACH_RCU(kid, &s->bus.qbus.children, sibling) { + SCSIDevice *d1 = SCSI_DEVICE(kid->child); + if (d1->channel == 0 && d1->id == target) { + device_cold_reset(&d1->qdev); + } } } - rcu_read_unlock(); qatomic_dec(&s->resetting); break;
Replace the manual rcu_read_(un)lock calls by the WITH_RCU_READ_LOCK_GUARD macro (See commit ef46ae67ba "docs/style: call out the use of GUARD macros"). Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> --- hw/scsi/virtio-scsi.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)