[PATCH 1/4] arm: topology: remove cpu_efficiency
Dietmar Eggemann
dietmar.eggemann at arm.com
Wed Sep 6 04:43:31 PDT 2017
Hi Vincent,
On 04/09/17 08:49, Vincent Guittot wrote:
> Hi Dietmar,
>
> Removing cpu effificiency table looks good to me. Nevertheless, i have
> some comments below for this patch.
Thanks for the review!
> On 30 August 2017 at 16:41, Dietmar Eggemann <dietmar.eggemann at arm.com> wrote:
>> Remove the 'cpu_efficiency/clock-frequency dt property' based solution
>> to set cpu capacity which was only working for Cortex-A15/A7 arm
>> big.LITTLE systems.
>>
>> I.e. the 'capacity-dmips-mhz' based solution is now the only one. It is
>> shared between arm and arm64 and works for every big.LITTLE system no
>> matter which core types it consists of.
>>
>> Cc: Russell King <linux at arm.linux.org.uk>
>> Cc: Vincent Guittot <vincent.guittot at linaro.org>
>> Cc: Juri Lelli <juri.lelli at arm.com>
>> Signed-off-by: Dietmar Eggemann <dietmar.eggemann at arm.com>
>> ---
>> arch/arm/kernel/topology.c | 113 ++-------------------------------------------
>> 1 file changed, 3 insertions(+), 110 deletions(-)
[...]
>> @@ -115,73 +70,13 @@ static void __init parse_dt_topology(void)
>> of_node_put(cn);
>> continue;
>
> AFAICT, this continue is now useless as it was there to skipe the cpu
> table efficiency method
You're right ... will remove it.
[...]
>> - if (cap_from_dt)
>> - topology_normalize_cpu_scale();
>
> Why have you moved the call to topology_normalize_cpu_scale() from
> parse_dt_topology() to update_cpu_capacity() ?
Didn't move it ? It's still called from parse_dt_topology().
> You should keep it in parse_dt_topology() as itis part of the dt
> parsing sequence
Yes, this should be the case.
[...]
>> -/*
>> - * Look for a customed capacity of a CPU in the cpu_capacity table during the
>> - * boot. The update of all CPUs is in O(n^2) for heteregeneous system but the
>> - * function returns directly for SMP system.
>> - */
>> -static void update_cpu_capacity(unsigned int cpu)
>> -{
>> - if (!cpu_capacity(cpu) || cap_from_dt)
>> - return;
>> -
>> - topology_set_cpu_scale(cpu, cpu_capacity(cpu) / middle_capacity);
>> -
>> - pr_info("CPU%u: update cpu_capacity %lu\n",
>> - cpu, topology_get_cpu_scale(NULL, cpu));
>> + topology_normalize_cpu_scale();
>> }
>
> You can probably just removed update_cpu_capacity()
I did remove update_cpu_capacity(). Maybe the patch layout is confusing?
[...]
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