On Fri, Apr 12, 2019 at 6:12 AM Jeff Moyer <[email protected]> wrote: > > Jan Kara <[email protected]> writes: > > > On Thu 11-04-19 07:51:48, Dan Williams wrote: > >> On Tue, Apr 9, 2019 at 9:09 PM Pankaj Gupta <[email protected]> wrote: > >> > + } else { > >> > + if (nd_region->flush(nd_region)) > >> > + rc = -EIO; > >> > >> Given the common case wants to be fast and synchronous I think we > >> should try to avoid retpoline overhead by default. So something like > >> this: > >> > >> if (nd_region->flush == generic_nvdimm_flush) > >> rc = generic_nvdimm_flush(...); > > > > I'd either add a comment about avoiding retpoline overhead here or just > > make ->flush == NULL mean generic_nvdimm_flush(). Just so that people don't > > get confused by the code. > > Isn't this premature optimization? I really don't like adding things > like this without some numbers to show it's worth it.
I don't think it's premature given this optimization technique is already being deployed elsewhere, see: https://lwn.net/Articles/774347/ _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
