On Wed, Aug 24, 2011 at 12:58:36AM +0000, KY Srinivasan wrote: > > > > -----Original Message----- > > From: Greg KH [mailto:greg@xxxxxxxxx] > > Sent: Tuesday, August 23, 2011 7:10 PM > > To: KY Srinivasan > > Cc: gregkh@xxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > > devel@xxxxxxxxxxxxxxxxxxxxxx; virtualization@xxxxxxxxxxxxxx; Haiyang Zhang > > Subject: Re: [PATCH 086/117] Staging: hv: storvsc: Leverage the spinlock to > > manage ref_cnt > > > > On Fri, Jul 15, 2011 at 10:47:14AM -0700, K. Y. Srinivasan wrote: > > > Now that we have a spin lock protecting access to the stor device pointer, > > > use it manage the reference count as well. > > > > > > Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > > > Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> > > > --- > > > drivers/staging/hv/hyperv_storage.h | 8 ++++---- > > > drivers/staging/hv/storvsc.c | 10 +++++----- > > > 2 files changed, 9 insertions(+), 9 deletions(-) > > > > > > diff --git a/drivers/staging/hv/hyperv_storage.h > > b/drivers/staging/hv/hyperv_storage.h > > > index 53b65be..d946211 100644 > > > --- a/drivers/staging/hv/hyperv_storage.h > > > +++ b/drivers/staging/hv/hyperv_storage.h > > > @@ -265,7 +265,7 @@ struct storvsc_device { > > > struct hv_device *device; > > > > > > /* 0 indicates the device is being destroyed */ > > > - atomic_t ref_count; > > > + int ref_count; > > > > Is this really needed? Can't you rely on the reference count of the > > hv_device itself? > > We don't have a reference count on the hv_device Wait, why not? You shure better have a reference count on that device if you have a pointer to it, if not, you have a bug, and that needs to be fixed. Please reread Documentation/CodingStyle for details. > and this count is taken to deal with racing unloads and incoming > traffic on the channel from the host. Is this something that all other storage drivers have to do? If not, then you shouldn't be doing that as well. greg k-h _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
