Merge branch 'pm-cpufreq'

Merge cpufreq updates for 7.4:

 - Minor fixes in various cpufreq drivers (Alexander Koskovich, Daniel
   Schwierzeck, Frank Zhang, Haotian Zhang, Kathiravan Thirumoorthy,
   Sumeet Pawnikar, and Xueqin Luo)

 - Fix wrong behaviors on multi-node servers in the Loongson cpufreq
   driver (Huacai Chen)

 - Reject NULL from cpufreq_cpu_get() in the Rust code (Mehmet Koseoglu)

 - Add suspend OPP to mediatek cpufreq driver and DT (Ryan Brue)

 - Fixups for a few bugs identified by Sashiko in the amd-pstate cpufreq
   driver (Mario Limoncielloi, Wentao Guan)

 - Initial support for maximum frequency capacity handling on Zen6
   client in amd-pstate (Mario Limonciello)

 - Fix for amd-pstate-ut with 'Requested CPU Min frequency' BIOS option
   (K Prateek Nayak)

 - New Zen6 tuning values for EPP in amd-pstate (Mario Limonciello,
   Vishal Badole)

 - amd-pstate documentation fix (Karl Mehltretter)

 - Restrict deferred downscaling to low load for shared policies in the
   conservative cpufreq governor to avoid undesirable CPU frequency
   reduction in some cases (Shengming Hu)

 - Serialize sugov_start() against rate limit updates in the schedutil
   cpufreq governor to avoid using a stale rate limit value (Hui Su)

* pm-cpufreq: (34 commits)
  cpufreq: loongson3: Replace IOCSR read/write with MMIO ones
  cpufreq: loongson3: Use global physical CPU ID in get/target callbacks
  cpufreq: loongson3: Replace per-package mutex with per-node
  cpufreq: loongson3: Adjust the width of id and val in smc_message
  cpufreq: loongson3: Make this driver depend on MACH_LOONGSON64
  cpufreq: schedutil: Serialize sugov_start() against rate limit updates
  arm64: dts: mediatek: mt8173: Mark the lowest CPU OPPs for suspend
  cpufreq: mediatek: Enter system sleep at the suspend OPP
  cpufreq: qcom-cpufreq-hw: fix device node refcount leak in phandle parsing
  cpufreq: qcom-nvmem: Add IPQ9650 support
  cpufreq: Add Milos to cpufreq-dt-platdev blocklist
  cpufreq: Use %pe to print error pointers symbolically
  rust: rcpufreq_dt: add module alias
  cpufreq: sti: avoid NULL dereference in dev_err()
  cpufreq: tegra194: fix double-pointer error in get_cpu_ndiv
  cpufreq: sparc-us2e: fix frequency table index copy-paste error
  rust: cpufreq: reject NULL from cpufreq_cpu_get()
  cpufreq: amd-pstate-ut: Fix max_freq and EPP test failures on Zen6
  cpufreq: amd-pstate: Propagate cppc_set_auto_sel() errors on mode change
  cpufreq: amd-pstate: Restore previous mode when changing driver mode fails
  ...

1 files changed, 13 insertions, 1 deletions

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 49ccd6f1c185..14405a614991 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -73,6 +73,18 @@ static void sugov_update_rate_limit_us(struct sugov_policy *sg_policy)
 		(s64)sg_policy->tunables->rate_limit_us * NSEC_PER_USEC;
 }
 
+static void sugov_update_rate_limit_us_sync(struct sugov_policy *sg_policy)
+{
+	/*
+	 * Serialize with rate_limit_us_store() to prevent this path from using
+	 * a stale rate limit tunable value to set the limit for the given
+	 * policy.
+	 */
+	guard(mutex)(&sg_policy->tunables->attr_set.update_lock);
+
+	sugov_update_rate_limit_us(sg_policy);
+}
+
 static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time)
 {
 	s64 delta_ns;
@@ -861,7 +873,7 @@ static int sugov_start(struct cpufreq_policy *policy)
 	void (*uu)(struct update_util_data *data, u64 time, unsigned int flags);
 	unsigned int cpu;
 
-	sugov_update_rate_limit_us(sg_policy);
+	sugov_update_rate_limit_us_sync(sg_policy);
 	sg_policy->last_freq_update_time	= 0;
 	sg_policy->next_freq			= 0;
 	sg_policy->work_in_progress		= false;