On Thu, 2015-03-19 at 10:59 -0700, Linus Torvalds wrote: > On Thu, Mar 19, 2015 at 10:21 AM, Jason Low <[email protected]> wrote: > > > > I tested this patch on a 32 bit ARM system with 4 cores. Using the > > generic 64 bit atomics, I did not see any performance change with this > > patch, and the relevant functions (account_group_*_time(), ect...) don't > > show up in perf reports. > > Ok. > > > One factor might be because locking/cacheline contention isn't as > > apparent on smaller systems to begin with, and lib/atomic64.c also > > mentions that "this is expected to used on systems with small numbers of > > CPUs (<= 4 or so)". > > Yeah, that's probably a valid argument anyway - 32-bit systems aren't > really going to be multi-node big systems any more. > > So I'm ok with the patch,
Okay, I will be sending out a v3 patch which will also mention a bit about its effect on 32 bit systems in the changelog, in addition to the changes that were discussed about in this thread (using WRITE_ONCE(), ect...). Thanks, Jason -- 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/
