[PATCH 07/15] cpufreq/amd-pstate: Only update the cached value in msr_set_epp() on success

From: Mario Limonciello
Date: Thu Dec 05 2024 - 17:30:08 EST


If writing the MSR MSR_AMD_CPPC_REQ fails then the cached value in the
amd_cpudata structure should not be updated.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
drivers/cpufreq/amd-pstate.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 14bd6faa3d730..ce70d1bfa55d0 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -278,11 +278,15 @@ static int msr_set_epp(struct amd_cpudata *cpudata, u32 epp)

value &= ~AMD_PSTATE_EPP_PERF_MASK;
value |= FIELD_PREP(AMD_PSTATE_EPP_PERF_MASK, epp);
- WRITE_ONCE(cpudata->cppc_req_cached, value);

ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
- if (!ret)
- cpudata->epp_cached = epp;
+ if (ret) {
+ pr_err("failed to set energy perf value (%d)\n", ret);
+ return ret;
+ }
+
+ cpudata->epp_cached = epp;
+ WRITE_ONCE(cpudata->cppc_req_cached, value);

return ret;
}
--
2.43.0