From: Rafael J. Wysocki <[email protected]>
When sugov_update_single_perf() falls back to the "frequency"
path due to the missing scale-invariance, it will call
cpufreq_driver_fast_switch() via sugov_fast_switch()
and the driver's ->fast_switch() callback will be invoked,
so it must not be NULL.
However, after commit a365ab6b9dfb ("cpufreq: intel_pstate: Implement
the ->adjust_perf() callback") intel_pstate sets ->fast_switch() to
NULL when it is going to use intel_cpufreq_adjust_perf(), which is a
mistake, because on x86 the scale-invariance may be turned off
dynamically, so modify it to retain the original ->adjust_perf()
callback pointer.
Fixes: a365ab6b9dfb ("cpufreq: intel_pstate: Implement the ->adjust_perf() callback")
Reported-by: Kenneth R. Crudup <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
---
drivers/cpufreq/intel_pstate.c | 1 -
1 file changed, 1 deletion(-)
Index: linux-pm/drivers/cpufreq/intel_pstate.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/intel_pstate.c
+++ linux-pm/drivers/cpufreq/intel_pstate.c
@@ -3088,7 +3088,6 @@ static int __init intel_pstate_init(void
intel_pstate.attr = hwp_cpufreq_attrs;
intel_cpufreq.attr = hwp_cpufreq_attrs;
intel_cpufreq.flags |= CPUFREQ_NEED_UPDATE_LIMITS;
- intel_cpufreq.fast_switch = NULL;
intel_cpufreq.adjust_perf = intel_cpufreq_adjust_perf;
if (!default_driver)
default_driver = &intel_pstate;