From: Dirk Brandewie <dirk.j.brande...@intel.com>

Change to use ->exit_prepare() callback to do clean up during CPU
hotplug. The requested P state for an offline core will be used by the
hardware coordination function to select the package P state. If the
core is under load when it is offlined it will fix the package P state
floor to the requested P state of offline core.

Reported-by: Patrick Marlier <patrick.marl...@gmail.com>
Signed-off-by: Dirk Brandewie <dirk.j.brande...@intel.com>
---
 drivers/cpufreq/intel_pstate.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 2cd36b9..fe32a8c 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -447,7 +447,7 @@ static void core_set_pstate(struct cpudata *cpudata, int 
pstate)
        if (limits.no_turbo)
                val |= (u64)1 << 32;
 
-       wrmsrl(MSR_IA32_PERF_CTL, val);
+       wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
 }
 
 static struct cpu_defaults core_params = {
@@ -773,16 +773,22 @@ static int intel_pstate_verify_policy(struct 
cpufreq_policy *policy)
        return 0;
 }
 
-static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
+static int intel_pstate_cpu_exit_prepare(struct cpufreq_policy *policy)
 {
-       int cpu = policy->cpu;
+       int cpu_num = policy->cpu;
+       struct cpudata *cpu = all_cpu_data[cpu_num];
+
+       pr_info("intel_pstate CPU %d exiting\n", cpu_num);
+
+       del_timer(&all_cpu_data[cpu_num]->timer);       
+       intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
+       kfree(all_cpu_data[cpu_num]);
+       all_cpu_data[cpu_num] = NULL;
 
-       del_timer(&all_cpu_data[cpu]->timer);
-       kfree(all_cpu_data[cpu]);
-       all_cpu_data[cpu] = NULL;
        return 0;
 }
 
+
 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
 {
        struct cpudata *cpu;
@@ -818,7 +824,7 @@ static struct cpufreq_driver intel_pstate_driver = {
        .setpolicy      = intel_pstate_set_policy,
        .get            = intel_pstate_get,
        .init           = intel_pstate_cpu_init,
-       .exit           = intel_pstate_cpu_exit,
+       .exit_prepare   = intel_pstate_cpu_exit_prepare,
        .name           = "intel_pstate",
 };
 
-- 
1.8.3.1

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