On Fri, 6 Jan 2017 09:00:23 +0100 Vlastimil Babka <[email protected]> wrote:
> On 01/06/2017 02:01 AM, Steven Rostedt wrote: > > Commit 682a3385e773 "mm, page_alloc: inline the fast path of the > > zonelist iterator" changed how next_zones_zonelist() is called, by > > adding a static inline function to do the fast path. This function adds: > > > > if (likely(!nodes && zonelist_zone_idx(z) <= highest_zoneidx)) > > Your profiling stats posted online suggested even this one was wrong: > > function.file.line correct incorrect percent > next_zones_zonelist.mmzone.h.965 216840653 25415261543 %0.85 > > Was it bogus then, or is there other explanation? I have speculated that > this might be due to multiple cpusets configured in the system. I didn't have any cpusets configured on either system. But the number is exaggerated, as it too was affected by the "constant" optimization by gcc. But when I fixed that, it still gives me about 50%. Probably best just to remove the likely() in that case. > Signed-off-by: Steven Rostedt (VMware) <[email protected]> > > Anyway this makes sense. > > Acked-by: Vlastimil Babka <[email protected]> Thanks! -- Steve
