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| author | Srivatsa Vaddagiri <vatsa@codeaurora.org> | 2014-04-15 14:43:57 -0700 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-23 21:25:58 -0700 |
| commit | 5796af4921425206827a6005412f43622cbfc0db (patch) | |
| tree | 3cd1cf810097e64c2c78e1ad67c9d7f487a66650 /arch/arm64 | |
| parent | 1ada6440876e3bbd2c99ce077978fda6d6ef53ca (diff) | |
arm64: topology: Define arch_get_cpu_efficiency() API for scheduler
On a HMP system, scheduler needs to know efficiency factor
(instructions-per-cycle) for various cpus. This is so that scheduler
can estimate bandwidth consumption of tasks on each cpu, based on
their efficiency factor.
This patch defines arch_get_cpu_efficiency() API in ARM64
architecture. It depends on hard-coded "efficiency" factor for
various cpu types (available in 'table_efficiency' data structure) and
device-tree providing information on cpu-type for every cpu.
Change-Id: Ied43ead650ab85b63c232bec14dde500cbcc0f7a
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
[joonwoop@codeaurora.org: s/SCHED_POWER/SCHED_CAPACITY/.]
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/kernel/topology.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 36ff723c6813..e562e0f43a42 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -209,6 +209,13 @@ static unsigned long *__cpu_capacity; static unsigned long middle_capacity = 1; +static DEFINE_PER_CPU(unsigned long, cpu_efficiency) = SCHED_CAPACITY_SCALE; + +unsigned long arch_get_cpu_efficiency(int cpu) +{ + return per_cpu(cpu_efficiency, cpu); +} + /* * Iterate all CPUs' descriptor in DT and compute the efficiency * (as per table_efficiency). Also calculate a middle efficiency @@ -288,6 +295,8 @@ static void __init parse_dt_cpu_power(void) continue; } + per_cpu(cpu_efficiency, cpu) = cpu_eff->efficiency; + rate = of_get_property(cn, "clock-frequency", &len); if (!rate || len != 4) { pr_err("%s: Missing clock-frequency property\n", |