diff options
| author | Mike Chan <mike@android.com> | 2011-10-01 14:16:07 +0100 |
|---|---|---|
| committer | Andy Green <andy.green@linaro.org> | 2011-10-02 09:38:29 +0100 |
| commit | f5e79b982fb58e27de02bc5cff53743122f1a902 (patch) | |
| tree | d9fc4aa47cca6d91c0c041c709c86421406bad75 /Documentation | |
| parent | e9cea122ef2eb2e6d2ede9e6e4acd18fcfff0786 (diff) | |
scheduler: cpuacct: Enable platform hooks to track cpuusage for CPU frequencies
Introduce new platform callback hooks for cpuacct for tracking CPU frequencies
Not all platforms / architectures have a set CPU_FREQ_TABLE defined
for CPU transition speeds. In order to track time spent in at various
CPU frequencies, we enable platform callbacks from cpuacct for this accounting.
Architectures that support overclock boosting, or don't have pre-defined
frequency tables can implement their own bucketing system that makes sense
given their cpufreq scaling abilities.
New file:
cpuacct.cpufreq reports the CPU time (in nanoseconds) spent at each CPU
frequency.
Change-Id: I10a80b3162e6fff3a8a2f74dd6bb37e88b12ba96
Signed-off-by: Mike Chan <mike@android.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/cgroups/cpuacct.txt | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/cgroups/cpuacct.txt b/Documentation/cgroups/cpuacct.txt index 9d73cc0cadb..ac8c648ae2b 100644 --- a/Documentation/cgroups/cpuacct.txt +++ b/Documentation/cgroups/cpuacct.txt @@ -39,6 +39,10 @@ system: Time spent by tasks of the cgroup in kernel mode. user and system are in USER_HZ unit. +cpuacct.cpufreq file gives CPU time (in nanoseconds) spent at each CPU +frequency. Platform hooks must be implemented inorder to properly track +time at each CPU frequency. + cpuacct controller uses percpu_counter interface to collect user and system times. This has two side effects: |