On Mon, Jan 28, 2013 at 11:07:58PM -0200, Marcelo Tosatti wrote: > On Mon, Jan 28, 2013 at 10:07:15PM -0200, Marcelo Tosatti wrote: > > On Fri, Jan 25, 2013 at 10:46:31AM +0800, Xiao Guangrong wrote: > > > On 01/25/2013 08:15 AM, Marcelo Tosatti wrote: > > > > On Wed, Jan 23, 2013 at 06:07:20PM +0800, Xiao Guangrong wrote: > > > >> It makes set_spte more clean and reduces branch prediction > > > >> > > > >> Signed-off-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxxxxxx> > > > >> --- > > > >> arch/x86/kvm/mmu.c | 37 ++++++++++++++++++++++++++----------- > > > >> 1 files changed, 26 insertions(+), 11 deletions(-) > > > > > > > > Don't see set_spte as being a performance problem? > > > > IMO the current code is quite simple. > > > > > > Yes, this is not a performance problem. > > > > > > I just dislike this many continuous "if"-s in the function: > > > > > > if (xxx) > > > xxx > > > if (xxx) > > > xxx > > > .... > > > > > > Totally, it has 7 "if"-s before this patch. > > > > > > Okay, if you think this is unnecessary, i will drop this patch. :) > > > > Yes, please (unless you can show set_spte is a performance problem). > > Same thing for spte fast drop: is it a performance problem? > I like spte fast drop because it gets rid of "goto restart" pattern. for_each_spte_in_rmap_safe() can be the alternative. > Please try to group changes into smaller, less controversial sets with > a clear goal: > > - Debated performance improvement. > - Cleanups (eg mmu_set_spte argument removal). > - Bug fixes. > - Performance improvements. > > Thanks. -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
