On Fri, 22 Jan 2016 12:49:05 +0530
Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com> wrote:
> Create sysfs attributes to export throttle information in
> /sys/devices/system/cpu/cpufreq/chipN. The newly added sysfs files are as
> follows:
>
> 1)/sys/devices/system/cpu/cpufreq/chip0/throttle_frequencies
> This gives the throttle stats for each of the available frequencies.
> The throttle stat of a frequency is the total number of times the max
> frequency is reduced to that frequency.
> # cat /sys/devices/system/cpu/cpufreq/chip0/throttle_frequencies
> 4023000 0
> 3990000 0
> 3956000 1
> 3923000 0
> 3890000 0
> 3857000 2
> 3823000 0
> 3790000 0
> 3757000 2
> 3724000 1
> 3690000 1
> ...
>
> 2)/sys/devices/system/cpu/cpufreq/chip0/throttle_reasons
> This directory contains throttle reason files. Each file gives the
> total number of times the max frequency is throttled, except for
> 'throttle_reset', which gives the total number of times the max
Is reset a good name? Ideally a reset, reset's stats.
> frequency is unthrottled after being throttled.
> # cd /sys/devices/system/cpu/cpufreq/chip0/throttle_reasons
> # cat cpu_over_temperature
> 7
> # cat occ_reset
> 0
> # cat over_current
> 0
> # cat power_cap
> 0
> # cat power_supply_failure
> 0
> # cat throttle_reset
> 7
>
> 3)/sys/devices/system/cpu/cpufreq/chip0/throttle_stat
> This gives the total number of events of max frequency throttling to
> lower frequencies in the turbo range of frequencies and the sub-turbo(at
> and below nominal) range of frequencies.
> # cat /sys/devices/system/cpu/cpufreq/chip0/throttle_stat
> turbo 7
> sub-turbo 0
>
> Signed-off-by: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com>
> Reviewed-by: Gautham R. Shenoy <e...@linux.vnet.ibm.com>
snip
>
> +enum throt_reason_type {
> + NO_THROTTLE = 0,
NO is not throttled or number_throttle?
> + POWERCAP,
> + CPU_OVERTEMP,
> + POWER_SUPPLY_FAILURE,
> + OVERCURRENT,
> + OCC_RESET_THROTTLE,
> + OCC_MAX_REASON
> +};
> +
> static struct chip {
> unsigned int id;
> bool throttled;
> @@ -62,6 +72,11 @@ static struct chip {
> u8 throt_reason;
> cpumask_t mask;
> struct work_struct throttle;
> + int throt_turbo;
The enum uses _THROTTLE so why can't the struct member
be throttle_nominal? throttle_turbo?
> + int throt_nominal;
> + int reason[OCC_MAX_REASON];
> + int *pstate_stat;
> + struct kobject *kobj;
> } *chips;
>
> static int nr_chips;
> @@ -196,6 +211,128 @@ static struct freq_attr *powernv_cpu_freq_attr[] = {
> NULL,
> };
>
> +static inline int get_chip_index(unsigned int id)
> +{
> + int i;
> +
> + for (i = 0; i < nr_chips; i++)
> + if (chips[i].id == id)
> + return i;
> +
> + return -EINVAL;
> +}
> +
> +static ssize_t throttle_freq_show(struct kobject *kobj,
> + struct kobj_attribute *attr, char *buf)
> +{
> + int i, count = 0, id;
> +
> + i = kstrtoint(kobj->name + 4, 0, &id);
Why the +4 magic, make it more readable?
> + if (i)
> + return i;
> +
> + id = get_chip_index(id);
> + if (id < 0) {
> + pr_warn_once("%s Matching chip-id not found\n", __func__);
The pr_warn_once should also print which chip-id was not found, please
add that to the print
> + return id;
> + }
> +
> + for (i = 0; i < powernv_pstate_info.nr_pstates; i++)
> + count += sprintf(&buf[count], "%d %d\n",
> + powernv_freqs[i].frequency,
> + chips[id].pstate_stat[i]);
> +
> + return count;
> +}
> +
> +static struct kobj_attribute attr_throttle_frequencies =
> +__ATTR(throttle_frequencies, 0444, throttle_freq_show, NULL);
> +
> +static ssize_t throttle_stat_show(struct kobject *kobj,
> + struct kobj_attribute *attr, char *buf)
> +{
> + int ret, id, count = 0;
> +
> + ret = kstrtoint(kobj->name + 4, 0, &id);
> + if (ret)
> + return ret;
> +
> + id = get_chip_index(id);
> + if (id < 0) {
> + pr_warn_once("%s Matching chip-id not found\n", __func__);
> + return id;
> + }
> +
The above 9 lines look like common code, you can easily collapse it
instead of repeating it
> + count += sprintf(&buf[count], "turbo %d\n", chips[id].throt_turbo);
> + count += sprintf(&buf[count], "sub-turbo %d\n",
> + chips[id].throt_nominal);
> +
> + return count;
> +}
> +
> +static struct kobj_attribute attr_throttle_stat =
> +__ATTR(throttle_stat, 0444, throttle_stat_show, NULL);
> +
> +#define define_throttle_reason_attr(attr_name, val) \
> +static ssize_t attr_name##_show(struct kobject *kobj,
> \
> + struct kobj_attribute *attr, char *buf) \
> +{ \
> + int ret, id; \
> + \
> + ret = kstrtoint(kobj->name + 4, 0, &id); \
> + if (ret) \
> + return ret; \
> + \
> + id = get_chip_index(id); \
> + if (id < 0) { \
> + pr_warn_once("%s Matching chip-id not found\n", __func__);\
> + return id; \
> + } \
> + \
> + return sprintf(buf, "%d\n", chips[id].reason[val]); \
> +} \
> + \
> +static struct kobj_attribute attr_##attr_name =
> \
> +__ATTR(attr_name, 0444, attr_name##_show, NULL)
> +
> +define_throttle_reason_attr(throttle_reset, NO_THROTTLE);
> +define_throttle_reason_attr(power_cap, POWERCAP);
> +define_throttle_reason_attr(cpu_over_temperature, CPU_OVERTEMP);
> +define_throttle_reason_attr(power_supply_failure, POWER_SUPPLY_FAILURE);
> +define_throttle_reason_attr(over_current, OVERCURRENT);
> +define_throttle_reason_attr(occ_reset, OCC_RESET_THROTTLE);
> +
> +static struct attribute *throttle_reason_attrs[] = {
> + &attr_throttle_reset.attr,
> + &attr_power_cap.attr,
> + &attr_cpu_over_temperature.attr,
> + &attr_power_supply_failure.attr,
> + &attr_over_current.attr,
> + &attr_occ_reset.attr,
> + NULL
> +};
> +
> +static struct attribute *throttle_stat_attrs[] = {
> + &attr_throttle_frequencies.attr,
> + &attr_throttle_stat.attr,
> + NULL
> +};
> +
> +static const struct attribute_group throttle_reason_group = {
> + .name = "throttle_reasons",
> + .attrs = throttle_reason_attrs,
> +};
> +
> +static const struct attribute_group throttle_stat_group = {
> + .attrs = throttle_stat_attrs,
> +};
> +
> +static const struct attribute_group *throttle_attr_groups[] = {
> + &throttle_stat_group,
> + &throttle_reason_group,
> + NULL
> +};
> +
> /* Helper routines */
>
> /* Access helpers to power mgt SPR */
> @@ -327,13 +464,15 @@ static void powernv_cpufreq_throttle_check(void *data)
> unsigned int cpu = smp_processor_id();
> unsigned int chip_id = core_to_chip_map[cpu_core_index_of_thread(cpu)];
> unsigned long pmsr;
> - int pmsr_pmax, i;
> + int pmsr_pmax, i, index;
>
> pmsr = get_pmspr(SPRN_PMSR);
>
> - for (i = 0; i < nr_chips; i++)
> - if (chips[i].id == chip_id)
> - break;
> + i = get_chip_index(chip_id);
> + if (unlikely(i < 0)) {
> + pr_warn_once("%s Matching chip-id not found\n", __func__);
> + return;
> + }
>
> /* Check for Pmax Capping */
> pmsr_pmax = (s8)PMSR_MAX(pmsr);
> @@ -341,10 +480,19 @@ static void powernv_cpufreq_throttle_check(void *data)
> if (chips[i].throttled)
> goto next;
> chips[i].throttled = true;
> - if (pmsr_pmax < powernv_pstate_info.nominal)
> + if (pmsr_pmax < powernv_pstate_info.nominal) {
> pr_warn_once("CPU %d on Chip %u has Pmax reduced below
> nominal frequency (%d < %d)\n",
> cpu, chips[i].id, pmsr_pmax,
> powernv_pstate_info.nominal);
> + chips[i].throt_nominal++;
> + } else {
> + chips[i].throt_turbo++;
> + }
> +
> + index = powernv_pstate_info.max - pmsr_pmax;
> + if (index >= 0 && index < powernv_pstate_info.nr_pstates)
> + chips[i].pstate_stat[index]++;
> +
> trace_powernv_throttle(chips[i].id,
> throttle_reason[chips[i].throt_reason],
> pmsr_pmax);
> @@ -512,13 +660,18 @@ static int powernv_cpufreq_occ_msg(struct
> notifier_block *nb,
> return 0;
> }
>
> - for (i = 0; i < nr_chips; i++)
> - if (chips[i].id == omsg.chip)
> - break;
> + i = get_chip_index(omsg.chip);
> + if (i < 0) {
> + pr_warn_once("%s Matching chip-id not found\n",
> + __func__);
> + return i;
> + }
>
> if (omsg.throttle_status >= 0 &&
> - omsg.throttle_status <= OCC_MAX_THROTTLE_STATUS)
> + omsg.throttle_status <= OCC_MAX_THROTTLE_STATUS) {
> chips[i].throt_reason = omsg.throttle_status;
> + chips[i].reason[omsg.throttle_status]++;
> + }
>
> if (!omsg.throttle_status)
> chips[i].restore = true;
> @@ -583,12 +736,38 @@ static int init_chip_info(void)
> goto free_chip_map;
>
> for (i = 0; i < nr_chips; i++) {
> + char name[10];
> +
> chips[i].id = chip[i];
> cpumask_copy(&chips[i].mask, cpumask_of_node(chip[i]));
> INIT_WORK(&chips[i].throttle, powernv_cpufreq_work_fn);
> + chips[i].pstate_stat = kcalloc(powernv_pstate_info.nr_pstates,
> + sizeof(int), GFP_KERNEL);
> + if (!chips[i].pstate_stat)
> + goto free;
> +
> + sprintf(name, "chip%d", chips[i].id);
> + chips[i].kobj = kobject_create_and_add(name,
> + cpufreq_global_kobject);
> + if (!chips[i].kobj)
> + goto free;
> +
> + ret = sysfs_create_groups(chips[i].kobj, throttle_attr_groups);
> + if (ret) {
> + pr_info("Chip %d failed to create throttle sysfs
> group\n",
> + chips[i].id);
> + goto free;
> + }
> }
>
> return 0;
> +free:
> + nr_chips = i;
> + for (i = 0; i <= nr_chips; i++) {
> + kobject_put(chips[i].kobj);
> + kfree(chips[i].pstate_stat);
> + }
> + kfree(chips);
> free_chip_map:
> kfree(core_to_chip_map);
> out:
> @@ -623,9 +802,17 @@ module_init(powernv_cpufreq_init);
>
> static void __exit powernv_cpufreq_exit(void)
> {
> + int i;
> +
> unregister_reboot_notifier(&powernv_cpufreq_reboot_nb);
> opal_message_notifier_unregister(OPAL_MSG_OCC,
> &powernv_cpufreq_opal_nb);
> +
> + for (i = 0; i < nr_chips; i++) {
> + kobject_put(chips[i].kobj);
> + kfree(chips[i].pstate_stat);
> + }
> +
> kfree(chips);
> kfree(core_to_chip_map);
> cpufreq_unregister_driver(&powernv_cpufreq_driver);
