On Thursday, September 10, 2015 06:52:22 AM Viresh Kumar wrote:
On 10-09-15, 03:41, Rafael J. Wysocki wrote:
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Passing a pointer and dereferencing it is generally less efficient than passing a number. Before the patch the core has to do the dereference before calling ->get, so it likely doesn't matter here, but the code churn from this change is quite substantial and the benefit from it is in the noise IMO.
Hmm.. Actually almost every other callback (bios_limit() is another one), passes the policy to the driver, and I thought always passing the policy will make it more symmetrical. And the expectation that the cpufreq drivers wouldn't need to use policy from the ->get() callback would be wrong. Even if there are only few users today. One is the acpi-cpufreq driver and others are the ones, that are using cpufreq_generic_get() :)
So the whole question is whether or not this is worth the whole code churn related to the exchange of callbacks.
At this point I really don't know. It depends on the design discussion I'd like to start.
Thanks, Rafael