Re: [PATCH v2 1/3] cpufreq: CPPC: Add cppc_cpufreq_search_cpu_data

From: Pierre Gondois
Date: Mon Apr 11 2022 - 06:34:05 EST




On 4/11/22 05:10, Viresh Kumar wrote:
On 07-04-22, 10:16, Pierre Gondois wrote:
From: Pierre Gondois <Pierre.Gondois@xxxxxxx>

cppc_cpufreq_get_cpu_data() allocates a new struct cppc_cpudata
for the input CPU at each call.

To search the struct associated with a cpu without allocating
a new one, add cppc_cpufreq_search_cpu_data().
Also add an early prototype.

This will be used in a later patch, when generating artificial
performance states to register an artificial Energy Model in the
cppc_cpufreq driver and enable the Energy Aware Scheduler for ACPI
based systems.

Signed-off-by: Pierre Gondois <Pierre.Gondois@xxxxxxx>
---
drivers/cpufreq/cppc_cpufreq.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index 82d370ae6a4a..ffcd9704add2 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -41,6 +41,8 @@
*/
static LIST_HEAD(cpu_data_list);
+static struct cppc_cpudata *cppc_cpufreq_search_cpu_data(unsigned int cpu);
+
static bool boost_supported;
struct cppc_workaround_oem_info {
@@ -479,6 +481,19 @@ static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)
policy->driver_data = NULL;
}
+static struct cppc_cpudata *
+cppc_cpufreq_search_cpu_data(unsigned int cpu)
+{
+ struct cppc_cpudata *iter, *tmp;
+
+ list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) {
+ if (cpumask_test_cpu(cpu, iter->shared_cpu_map))
+ return iter;
+ }
+
+ return NULL;
+}

Did you miss this in cppc_cpufreq_cpu_init() ?

policy->driver_data = cpu_data;

The data is saved inside the policy and it shouldn't be difficult to
fetch it from there, instead of going through the list.


A previous (internal) implementation required this function,
but this is not necessary anymore indeed. I will drop this patch,
Thanks for the review,
Pierre