----- Original Message ----- > From: "Ewan D. Milne" <[email protected]> > To: [email protected] > Sent: Friday, May 20, 2016 8:56:14 AM > Subject: [PATCH] scsi: use spinlock instead of mutex for RCU-protected VPD > inquiry data > > From: "Ewan D. Milne" <[email protected]> > > A spinlock is sufficient for this purpose, and much smaller. > > Signed-off-by: Ewan D. Milne <[email protected]> > --- > drivers/scsi/scsi.c | 8 ++++---- > drivers/scsi/scsi_scan.c | 2 +- > include/scsi/scsi_device.h | 2 +- > 3 files changed, 6 insertions(+), 6 deletions(-) > > diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c > index 1deb6ad..330d807 100644 > --- a/drivers/scsi/scsi.c > +++ b/drivers/scsi/scsi.c > @@ -829,11 +829,11 @@ retry_pg80: > kfree(vpd_buf); > goto retry_pg80; > } > - mutex_lock(&sdev->inquiry_mutex); > + spin_lock(&sdev->inquiry_lock); > orig_vpd_buf = sdev->vpd_pg80; > sdev->vpd_pg80_len = result; > rcu_assign_pointer(sdev->vpd_pg80, vpd_buf); > - mutex_unlock(&sdev->inquiry_mutex); > + spin_unlock(&sdev->inquiry_lock); > synchronize_rcu(); > if (orig_vpd_buf) { > kfree(orig_vpd_buf); > @@ -858,11 +858,11 @@ retry_pg83: > kfree(vpd_buf); > goto retry_pg83; > } > - mutex_lock(&sdev->inquiry_mutex); > + spin_lock(&sdev->inquiry_lock); > orig_vpd_buf = sdev->vpd_pg83; > sdev->vpd_pg83_len = result; > rcu_assign_pointer(sdev->vpd_pg83, vpd_buf); > - mutex_unlock(&sdev->inquiry_mutex); > + spin_unlock(&sdev->inquiry_lock); > synchronize_rcu(); > if (orig_vpd_buf) > kfree(orig_vpd_buf); > diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c > index e0a78f5..f445615 100644 > --- a/drivers/scsi/scsi_scan.c > +++ b/drivers/scsi/scsi_scan.c > @@ -240,7 +240,7 @@ static struct scsi_device *scsi_alloc_sdev(struct > scsi_target *starget, > INIT_LIST_HEAD(&sdev->starved_entry); > INIT_LIST_HEAD(&sdev->event_list); > spin_lock_init(&sdev->list_lock); > - mutex_init(&sdev->inquiry_mutex); > + spin_lock_init(&sdev->inquiry_lock); > INIT_WORK(&sdev->event_work, scsi_evt_thread); > INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue); > > diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h > index a6c346d..0410ed8 100644 > --- a/include/scsi/scsi_device.h > +++ b/include/scsi/scsi_device.h > @@ -115,7 +115,7 @@ struct scsi_device { > char type; > char scsi_level; > char inq_periph_qual; /* PQ from INQUIRY data */ > - struct mutex inquiry_mutex; > + spinlock_t inquiry_lock; > unsigned char inquiry_len; /* valid bytes in 'inquiry' */ > unsigned char * inquiry; /* INQUIRY response data */ > const char * vendor; /* [back_compat] point into 'inquiry' > ... */ > -- > 2.1.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html >
Look fine to me: Reviewed by: Laurence Oberman <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
