| Message ID | 20230504235052.4423-2-bvanassche@acm.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ufs: Do not requeue while ungating the clock | expand |
On 5/4/23 6:50 PM, Bart Van Assche wrote: > Make scsi_host_block() easier to read by converting it to the widely used > early-return style. This patch reworks code introduced by commit > f983622ae605 ("scsi: core: Avoid calling synchronize_rcu() for each device > in scsi_host_block()"). > > Cc: Ming Lei <ming.lei@redhat.com> > Cc: Ye Bin <yebin10@huawei.com> > Cc: Hannes Reinecke <hare@suse.de> > Signed-off-by: Bart Van Assche <bvanassche@acm.org> > --- > drivers/scsi/scsi_lib.c | 18 +++++++++++++----- > 1 file changed, 13 insertions(+), 5 deletions(-) > > diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c > index b7c569a42aa4..758a57616dd3 100644 > --- a/drivers/scsi/scsi_lib.c > +++ b/drivers/scsi/scsi_lib.c > @@ -2939,11 +2939,20 @@ scsi_target_unblock(struct device *dev, enum scsi_device_state new_state) > } > EXPORT_SYMBOL_GPL(scsi_target_unblock); > > +/** > + * scsi_host_block - Try to transition all logical units to the SDEV_BLOCK state > + * @shost: device to block > + * > + * Pause SCSI command processing for all logical units associated with the SCSI > + * host and wait until pending scsi_queue_rq() calls have finished. > + * > + * Returns zero if successful or a negative error code upon failure. > + */ > int > scsi_host_block(struct Scsi_Host *shost) > { > struct scsi_device *sdev; > - int ret = 0; > + int ret; > > /* > * Call scsi_internal_device_block_nowait so we can avoid > @@ -2955,7 +2964,7 @@ scsi_host_block(struct Scsi_Host *shost) > mutex_unlock(&sdev->state_mutex); > if (ret) { > scsi_device_put(sdev); > - break; > + return ret; > } > } > > @@ -2965,10 +2974,9 @@ scsi_host_block(struct Scsi_Host *shost) > */ > WARN_ON_ONCE(shost->tag_set.flags & BLK_MQ_F_BLOCKING); > > - if (!ret) > - synchronize_rcu(); > + synchronize_rcu(); > > - return ret; > + return 0; > } > EXPORT_SYMBOL_GPL(scsi_host_block); > Reviewed-by: Mike Christie <michael.christie@oracle.com>
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index b7c569a42aa4..758a57616dd3 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2939,11 +2939,20 @@ scsi_target_unblock(struct device *dev, enum scsi_device_state new_state) } EXPORT_SYMBOL_GPL(scsi_target_unblock); +/** + * scsi_host_block - Try to transition all logical units to the SDEV_BLOCK state + * @shost: device to block + * + * Pause SCSI command processing for all logical units associated with the SCSI + * host and wait until pending scsi_queue_rq() calls have finished. + * + * Returns zero if successful or a negative error code upon failure. + */ int scsi_host_block(struct Scsi_Host *shost) { struct scsi_device *sdev; - int ret = 0; + int ret; /* * Call scsi_internal_device_block_nowait so we can avoid @@ -2955,7 +2964,7 @@ scsi_host_block(struct Scsi_Host *shost) mutex_unlock(&sdev->state_mutex); if (ret) { scsi_device_put(sdev); - break; + return ret; } } @@ -2965,10 +2974,9 @@ scsi_host_block(struct Scsi_Host *shost) */ WARN_ON_ONCE(shost->tag_set.flags & BLK_MQ_F_BLOCKING); - if (!ret) - synchronize_rcu(); + synchronize_rcu(); - return ret; + return 0; } EXPORT_SYMBOL_GPL(scsi_host_block);
Make scsi_host_block() easier to read by converting it to the widely used early-return style. This patch reworks code introduced by commit f983622ae605 ("scsi: core: Avoid calling synchronize_rcu() for each device in scsi_host_block()"). Cc: Ming Lei <ming.lei@redhat.com> Cc: Ye Bin <yebin10@huawei.com> Cc: Hannes Reinecke <hare@suse.de> Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- drivers/scsi/scsi_lib.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)