6f5f3ec34f
In https://github.com/torvalds/linux/commit/5ca3726 (released in v4.7-rc1) the content of the `cpuacct.usage_percpu` file in sysfs was changed to include both online and offline cpus. This broke the arithmetic in the stats helpers used by `docker stats`, since it was using the length of the PerCPUUsage array as a proxy for the number of online CPUs. Add current number of online CPUs to types.StatsJSON and use it in the calculation. Keep a fallback to `len(v.CPUStats.CPUUsage.PercpuUsage)` so this code continues to work when talking to an older daemon. An old client talking to a new daemon will ignore the new field and behave as before. Fixes #28941. Signed-off-by: Ian Campbell <ian.campbell@docker.com> Upstream-commit: 115f91d7575d6de6c7781a96a082f144fd17e400 Component: engine