PM: QoS: Invalidate frequency QoS requests after removal

Switching cpufreq drivers (or switching operation modes of the
intel_pstate driver from "active" to "passive" and vice versa)
does not work on some x86 systems with ACPI after commit
3000ce3c52 ("cpufreq: Use per-policy frequency QoS"), because
the ACPI _PPC and thermal code uses the same frequency QoS request
object for a given CPU every time a cpufreq driver is registered
and freq_qos_remove_request() does not invalidate the request after
removing it from its QoS list, so freq_qos_add_request() complains
and fails when that request is passed to it again.

Fix the issue by modifying freq_qos_remove_request() to clear the qos
and type fields of the frequency request pointed to by its argument
after removing it from its QoS list so as to invalidate it.

Fixes: 3000ce3c52 ("cpufreq: Use per-policy frequency QoS")
Reported-and-tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
This commit is contained in:
Rafael J. Wysocki 2019-11-20 10:33:34 +01:00
parent af42d3466b
commit 05ff1ba412

View File

@ -814,6 +814,8 @@ EXPORT_SYMBOL_GPL(freq_qos_update_request);
*/
int freq_qos_remove_request(struct freq_qos_request *req)
{
int ret;
if (!req)
return -EINVAL;
@ -821,7 +823,11 @@ int freq_qos_remove_request(struct freq_qos_request *req)
"%s() called for unknown object\n", __func__))
return -EINVAL;
return freq_qos_apply(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
ret = freq_qos_apply(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE);
req->qos = NULL;
req->type = 0;
return ret;
}
EXPORT_SYMBOL_GPL(freq_qos_remove_request);