David Hildenbrand <david@xxxxxxxxxx> writes:
> On 28.10.23 02:09, Stefan Roesch wrote:
>> This adds four new knobs for the KSM advisor to influence its behaviour.
>> The knobs are:
>> - advisor_mode:
>> 0: no advisor (default)
>> 1: scan time advisor
>> - advisor_min_cpu: 15 (default, cpu usage percent)
>> - advisor_max_cpu: 70 (default, cpu usage percent)
>> - advisor_min_pages: 500 (default)
>> - advisor_max_pages: 30000 (default)
>> - advisor_target_scan_time: 200 (default in seconds)
>> The new values will take effect on the next scan round.
>> Signed-off-by: Stefan Roesch <shr@xxxxxxxxxxxx>
>> ---
>> mm/ksm.c | 154 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> 1 file changed, 154 insertions(+)
>> diff --git a/mm/ksm.c b/mm/ksm.c
>> index e18fecfb359d..042ecaeb0beb 100644
>> --- a/mm/ksm.c
>> +++ b/mm/ksm.c
>> @@ -351,6 +351,14 @@ static void init_advisor(void)
>> advisor_ctx.cpu_time = 0;
>> }
>
>
> [...]
>
>> * Use previous scan time if available, otherwise use current scan time as an
>> * approximation for the previous scan time.
>> @@ -3719,6 +3727,146 @@ static ssize_t smart_scan_store(struct kobject *kobj,
>> }
>> KSM_ATTR(smart_scan);
>> +static ssize_t advisor_mode_show(struct kobject *kobj,
>> + struct kobj_attribute *attr, char *buf)
>> +{
>> + return sysfs_emit(buf, "%u\n", ksm_advisor);
>> +}
>> +
>> +static ssize_t advisor_mode_store(struct kobject *kobj,
>> + struct kobj_attribute *attr, const char *buf,
>> + size_t count)
>> +{
>> + unsigned int mode;
>> + int err;
>> +
>> + err = kstrtouint(buf, 10, &mode);
>> + if (err)
>> + return -EINVAL;
>> + if (mode > KSM_ADVISOR_LAST)
>> + return -EINVAL;
>> +
>> + /* Set advisor default values */
>> + ksm_advisor = mode;
>> + init_advisor();
>> + set_advisor_defaults();
>> +
>> + return count;
>
> Can we instead use human-readable strings?
>
> "none" and "scan-time" should be clearer.
>
I'll change the interface to use strings instead of numbers.
