cpufreq: intel_pstate: Adjust frequency percentage computations

Adjust frequency percentage computations in update_cpu_qos_request() to
avoid going above the exact numerical percentage in the FREQ_QOS_MAX
case.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
Link: https://patch.msgid.link/3395556.44csPzL39Z@rafael.j.wysocki
[ rjw: Rename "cpu" to "cpudata" and "cpunum" to "cpu" ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 33a3debb139f9d978e706eb411cca440df17874b..20746c35d3ba27d19a95f8225111828df2284570 100644 (file)
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1655,8 +1655,8 @@ unlock_driver:
 static void update_cpu_qos_request(int cpu, enum freq_qos_req_type type)
 {
        struct cpudata *cpudata = all_cpu_data[cpu];
+       unsigned int freq = cpudata->pstate.turbo_freq;
        struct freq_qos_request *req;
-       unsigned int freq, perf_pct;
 
        struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpu);
        if (!policy)
@@ -1670,14 +1670,12 @@ static void update_cpu_qos_request(int cpu, enum freq_qos_req_type type)
                intel_pstate_get_hwp_cap(cpudata);
 
        if (type == FREQ_QOS_MIN) {
-               perf_pct = global.min_perf_pct;
+               freq = DIV_ROUND_UP(freq * global.min_perf_pct, 100);
        } else {
                req++;
-               perf_pct = global.max_perf_pct;
+               freq = (freq * global.max_perf_pct) / 100;
        }
 
-       freq = DIV_ROUND_UP(cpudata->pstate.turbo_freq * perf_pct, 100);
-
        if (freq_qos_update_request(req, freq) < 0)
                pr_warn("Failed to update freq constraint: CPU%d\n", cpu);
 }