On Fri, May 09, 2014 at 03:41:40PM -0400, Tejun Heo wrote: > On Fri, May 09, 2014 at 12:40:21PM -0700, Kent Overstreet wrote: > > On Wed, May 07, 2014 at 11:58:10AM -0400, Tejun Heo wrote: > > > Implement percpu_ref_tryget() which fails if the refcnt already > > > reached zero. Note that this is different from the recently renamed > > > percpu_ref_tryget_live() which fails if the refcnt has been killed and > > > is draining the remaining references. percpu_ref_tryget() succeeds on > > > a killed refcnt as long as its current refcnt is above zero. > > > > I'd still kind of prefer tryget() to be labelled "deprecated, don't use > > outside > > the cgroup code" or somesuch, but it's not a huge deal :) > > Hmmm... why would it be deprecated? These are just two different > operations.
Well not so much deprecated as "bad, avoid" - IMO using tryget() almost always (I haven't seen a convincing counterexample) means you screwed up your refcounting somewhere, if you need to take a ref on something whatever made that object visible to you should have its own ref. (I think we had this debate, but that was awhile ago...) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
