From: Wyes Karny wyes.karny@amd.com
commit 3bf8c6307bad5c0cc09cde982e146d847859b651 upstream.
Driver should update policy->cur after updating the frequency. Currently amd_pstate doesn't update policy->cur when `adjust_perf` is used. Which causes /proc/cpuinfo to show wrong cpu frequency. Fix this by updating policy->cur with correct frequency value in adjust_perf function callback.
- Before the fix: (setting min freq to 1.5 MHz)
[root@amd]# cat /proc/cpuinfo | grep "cpu MHz" | sort | uniq --count 1 cpu MHz : 1777.016 1 cpu MHz : 1797.160 1 cpu MHz : 1797.270 189 cpu MHz : 400.000
- After the fix: (setting min freq to 1.5 MHz)
[root@amd]# cat /proc/cpuinfo | grep "cpu MHz" | sort | uniq --count 1 cpu MHz : 1753.353 1 cpu MHz : 1756.838 1 cpu MHz : 1776.466 1 cpu MHz : 1776.873 1 cpu MHz : 1777.308 1 cpu MHz : 1779.900 183 cpu MHz : 1805.231 1 cpu MHz : 1956.815 1 cpu MHz : 2246.203 1 cpu MHz : 2259.984
Fixes: 1d215f0319c2 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State") Signed-off-by: Wyes Karny wyes.karny@amd.com [ rjw: Subject edits ] Cc: 5.17+ stable@vger.kernel.org # 5.17+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/cpufreq/amd-pstate.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -284,12 +284,14 @@ static void amd_pstate_adjust_perf(unsig unsigned long capacity) { unsigned long max_perf, min_perf, des_perf, - cap_perf, lowest_nonlinear_perf; + cap_perf, lowest_nonlinear_perf, max_freq; struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); struct amd_cpudata *cpudata = policy->driver_data; + unsigned int target_freq;
cap_perf = READ_ONCE(cpudata->highest_perf); lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf); + max_freq = READ_ONCE(cpudata->max_freq);
des_perf = cap_perf; if (target_perf < capacity) @@ -306,6 +308,10 @@ static void amd_pstate_adjust_perf(unsig if (max_perf < min_perf) max_perf = min_perf;
+ des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf); + target_freq = div_u64(des_perf * max_freq, max_perf); + policy->cur = target_freq; + amd_pstate_update(cpudata, min_perf, des_perf, max_perf, true); cpufreq_cpu_put(policy); }