There are two types of forced idle time: forced idle time from cookie'd task and forced idle time form uncookie'd task. The forced idle time from uncookie'd task is actually caused by the cookie'd task in runqueue indirectly, and it's more accurate to measure the capacity loss with the sum of both. This patch set accounts forced idle time for each cpu to measure how long the cpu is forced idle, which is displayed via via /proc/schedstat, and also accounts for each cgroup to measure how long it forced its SMT siblings into idle, which is displayed via /sys/fs/cgroup/cpuacct/cpuacct.forceidle and /sys/fs/cgroup/cpuacct/cpuacct.forceidle_percpu. It is worth noting that the forced idle time and the force idle time have different meanings. We can get the total system forced idle time by looking at the root cgroup, and we can get how long the cgroup forced it SMT siblings into idle. If the force idle time of a cgroup is high, that can be rectified by making some changes(ie. affinity, cpu budget, etc.) to the cgroup. Cruz Zhao (3): sched/core: Accounting forceidle time for all tasks except idle task sched/core: Forced idle accounting per-cpu sched/core: Force idle accounting per cgroup include/linux/cgroup.h | 7 +++++ kernel/sched/core.c | 10 ++++-- kernel/sched/core_sched.c | 10 ++++-- kernel/sched/cpuacct.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++ kernel/sched/sched.h | 4 +++ kernel/sched/stats.c | 17 ++++++++-- 6 files changed, 119 insertions(+), 8 deletions(-) -- 1.8.3.1
