6 files changed, 43 insertions, 27 deletions

diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index cfc7a57049e4..c8c272df7154 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -14,7 +14,6 @@
 
 #include <linux/export.h>
 #include <linux/suspend.h>
-#include <linux/syscalls.h>
 #include <linux/reboot.h>
 #include <linux/string.h>
 #include <linux/device.h>
@@ -709,9 +708,7 @@ int hibernate(void)
                 goto Exit;
         }
 
-        pr_info("Syncing filesystems ... \n");
-        ksys_sync();
-        pr_info("done.\n");
+        ksys_sync_helper();
 
         error = freeze_processes();
         if (error)
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 98e76cad128b..4f43e724f6eb 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -16,6 +16,7 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/suspend.h>
+#include <linux/syscalls.h>
 
 #include "power.h"
 
@@ -51,6 +52,19 @@ void unlock_system_sleep(void)
 }
 EXPORT_SYMBOL_GPL(unlock_system_sleep);
 
+void ksys_sync_helper(void)
+{
+        ktime_t start;
+        long elapsed_msecs;
+
+        start = ktime_get();
+        ksys_sync();
+        elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
+        pr_info("Filesystems sync: %ld.%03ld seconds\n",
+                elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
+}
+EXPORT_SYMBOL_GPL(ksys_sync_helper);
+
 /* Routines for PM-transition notifications */
 
 static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 59b6def23046..ef908c134b34 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -17,7 +17,6 @@
 #include <linux/console.h>
 #include <linux/cpu.h>
 #include <linux/cpuidle.h>
-#include <linux/syscalls.h>
 #include <linux/gfp.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
@@ -568,13 +567,11 @@ static int enter_state(suspend_state_t state)
         if (state == PM_SUSPEND_TO_IDLE)
                 s2idle_begin();
 
-#ifndef CONFIG_SUSPEND_SKIP_SYNC
-        trace_suspend_resume(TPS("sync_filesystems"), 0, true);
-        pr_info("Syncing filesystems ... ");
-        ksys_sync();
-        pr_cont("done.\n");
-        trace_suspend_resume(TPS("sync_filesystems"), 0, false);
-#endif
+        if (!IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC)) {
+                trace_suspend_resume(TPS("sync_filesystems"), 0, true);
+                ksys_sync_helper();
+                trace_suspend_resume(TPS("sync_filesystems"), 0, false);
+        }
 
         pm_pr_dbg("Preparing system for sleep (%s)\n", mem_sleep_labels[state]);
         pm_suspend_clear_flags();
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 2d8b60a3c86b..cb24e840a3e6 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -10,7 +10,6 @@
  */
 
 #include <linux/suspend.h>
-#include <linux/syscalls.h>
 #include <linux/reboot.h>
 #include <linux/string.h>
 #include <linux/device.h>
@@ -228,9 +227,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
                 if (data->frozen)
                         break;
 
-                printk("Syncing filesystems ... ");
-                ksys_sync();
-                printk("done.\n");
+                ksys_sync_helper();
 
                 error = freeze_processes();
                 if (error)
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 3638d2377e3c..5403479073b0 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -13,6 +13,8 @@
 #include <linux/sched/cpufreq.h>
 #include <trace/events/power.h>
 
+#define IOWAIT_BOOST_MIN        (SCHED_CAPACITY_SCALE / 8)
+
 struct sugov_tunables {
         struct gov_attr_set     attr_set;
         unsigned int            rate_limit_us;
@@ -51,7 +53,6 @@ struct sugov_cpu {
         u64                     last_update;
 
         unsigned long           bw_dl;
-        unsigned long           min;
         unsigned long           max;
 
         /* The field below is for single-CPU policies only: */
@@ -291,8 +292,8 @@ static unsigned long sugov_get_util(struct sugov_cpu *sg_cpu)
  *
  * The IO wait boost of a task is disabled after a tick since the last update
  * of a CPU. If a new IO wait boost is requested after more then a tick, then
- * we enable the boost starting from the minimum frequency, which improves
- * energy efficiency by ignoring sporadic wakeups from IO.
+ * we enable the boost starting from IOWAIT_BOOST_MIN, which improves energy
+ * efficiency by ignoring sporadic wakeups from IO.
  */
 static bool sugov_iowait_reset(struct sugov_cpu *sg_cpu, u64 time,
                                bool set_iowait_boost)
@@ -303,7 +304,7 @@ static bool sugov_iowait_reset(struct sugov_cpu *sg_cpu, u64 time,
         if (delta_ns <= TICK_NSEC)
                 return false;
 
-        sg_cpu->iowait_boost = set_iowait_boost ? sg_cpu->min : 0;
+        sg_cpu->iowait_boost = set_iowait_boost ? IOWAIT_BOOST_MIN : 0;
         sg_cpu->iowait_boost_pending = set_iowait_boost;
 
         return true;
@@ -317,8 +318,9 @@ static bool sugov_iowait_reset(struct sugov_cpu *sg_cpu, u64 time,
  *
  * Each time a task wakes up after an IO operation, the CPU utilization can be
  * boosted to a certain utilization which doubles at each "frequent and
- * successive" wakeup from IO, ranging from the utilization of the minimum
- * OPP to the utilization of the maximum OPP.
+ * successive" wakeup from IO, ranging from IOWAIT_BOOST_MIN to the utilization
+ * of the maximum OPP.
+ *
  * To keep doubling, an IO boost has to be requested at least once per tick,
  * otherwise we restart from the utilization of the minimum OPP.
  */
@@ -349,7 +351,7 @@ static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, u64 time,
         }
 
         /* First wakeup after IO: start with minimum boost */
-        sg_cpu->iowait_boost = sg_cpu->min;
+        sg_cpu->iowait_boost = IOWAIT_BOOST_MIN;
 }
 
 /**
@@ -389,7 +391,7 @@ static unsigned long sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
                  * No boost pending; reduce the boost value.
                  */
                 sg_cpu->iowait_boost >>= 1;
-                if (sg_cpu->iowait_boost < sg_cpu->min) {
+                if (sg_cpu->iowait_boost < IOWAIT_BOOST_MIN) {
                         sg_cpu->iowait_boost = 0;
                         return util;
                 }
@@ -827,9 +829,6 @@ static int sugov_start(struct cpufreq_policy *policy)
                 memset(sg_cpu, 0, sizeof(*sg_cpu));
                 sg_cpu->cpu                     = cpu;
                 sg_cpu->sg_policy               = sg_policy;
-                sg_cpu->min                     =
-                        (SCHED_CAPACITY_SCALE * policy->cpuinfo.min_freq) /
-                        policy->cpuinfo.max_freq;
         }
 
         for_each_cpu(cpu, policy->cpus) {
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index bdf00c763ee3..f4ee1a3428ae 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -1038,6 +1038,18 @@ bool tick_nohz_idle_got_tick(void)
 }
 
 /**
+ * tick_nohz_get_next_hrtimer - return the next expiration time for the hrtimer
+ * or the tick, whatever that expires first. Note that, if the tick has been
+ * stopped, it returns the next hrtimer.
+ *
+ * Called from power state control code with interrupts disabled
+ */
+ktime_t tick_nohz_get_next_hrtimer(void)
+{
+        return __this_cpu_read(tick_cpu_device.evtdev)->next_event;
+}
+
+/**
  * tick_nohz_get_sleep_length - return the expected length of the current sleep
  * @delta_next: duration until the next event if the tick cannot be stopped
  *