Hi Peter, > On Oct 10, 2018, at 3:45 AM, Peter Zijlstra <pet...@infradead.org> wrote: > > Hi all, > > There have been various issues and limitations with the way perf uses > (task) contexts to track events. Most notable is the single hardware PMU > task context, which has resulted in a number of yucky things (both > proposed and merged). > > Notably: > > - HW breakpoint PMU > - ARM big.little PMU > - Intel Branch Monitoring PMU > > Since we now track the events in RB trees, we can 'simply' add a pmu > order to them and have them grouped that way, reducing to a single > context. Of course, reality never quite works out that simple, and below > ends up adding an intermediate data structure to bridge the context -> > pmu mapping. > > Something a little like: > > ,------------------------[1:n]---------------------. > V V > perf_event_context <-[1:n]-> perf_event_pmu_context <--- perf_event > ^ ^ | | > `--------[1:n]---------' `-[n:1]-> pmu <-[1:n]-' > > This patch builds (provided you disable CGROUP_PERF), boots and survives > perf-top without the machine catching fire. > > There's still a fair bit of loose ends (look for XXX), but I think this > is the direction we should be going. > > Comments?
This might be a little off topic... What's you plan about this effort and the PMU sharing work (https://lkml.org/lkml/2018/10/4/10)? Would PMU sharing work better/simpler with this effort? Thanks, Song
