On Tue, Aug 20 2013 at 4:09am -0400, Ingo Molnar <mingo@xxxxxxxxxx> wrote: > > * Stanislaw Gruszka <sgruszka@xxxxxxxxxx> wrote: > > > On Fri, Aug 09, 2013 at 03:56:03PM -0400, Mike Snitzer wrote: > > > This reverts commit f3002134158092178be81339ec5a22ff80e6c308. > > > > > > div64_u64_rem was removed because there were no other users. > > > > > > But Device Mapper's I/O statistics support has a need for > > > div64_u64_rem; reintroduce this helper. > > > > This slows down div64_u64 operation, especially on 32-bit > > systems. > > > > Since dm statistic code is possibly not performance > > critical perhaps you could use something like below > > instead to calculate remainder: > > > > res = div64_u64(a, b); > > rem = a - b*res; > > Or introduce a separately named helper without touching the > existing methods. Thanks for the feedback. I've pushed "math64: New separate div64_u64_rem helper" to the DM tree's 'for-next' branch: https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=for-next&id=20e8125736d0e96b64c9b6127241d2a13529180a Are you OK with me carrying this patch in the DM tree for 3.12 inclusion? Mike -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
