[PATCH 1/4] arm: topology: remove cpu_efficiency
vincent.guittot at linaro.org
Wed Sep 6 05:40:12 PDT 2017
On 6 September 2017 at 13:43, Dietmar Eggemann <dietmar.eggemann at arm.com> wrote:
> 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)
>> 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?
yes you're right I have been confused by the layout
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