ANDROID: cpufreq: track per-task time in state
Add time in state data to task structs, and create
/proc/<pid>/time_in_state files to show how long each individual task
has run at each frequency.
Create a CONFIG_CPU_FREQ_TIMES option to enable/disable this tracking.
Bug: 72339335
Bug: 127641090
Test: Read /proc/<pid>/time_in_state
Change-Id: Ia6456754f4cb1e83b2bc35efa8fbe9f8696febc8
Signed-off-by: Connor O'Brien <connoro@google.com>
[astrachan: Folded the following changes into this patch:
a6d3de6a7fba ("ANDROID: Reduce use of #ifdef CONFIG_CPU_FREQ_TIMES")
b89ada5d9c09 ("ANDROID: Fix massive cpufreq_times memory leaks")]
Signed-off-by: Alistair Strachan <astrachan@google.com>
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 608af20..e131237 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -37,6 +37,13 @@
If in doubt, say N.
+config CPU_FREQ_TIMES
+ bool "CPU frequency time-in-state statistics"
+ help
+ Export CPU time-in-state information through procfs.
+
+ If in doubt, say N.
+
choice
prompt "Default CPUFreq governor"
default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index c1ffeab..648beca 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -5,7 +5,10 @@
# CPUfreq stats
obj-$(CONFIG_CPU_FREQ_STAT) += cpufreq_stats.o
-# CPUfreq governors
+# CPUfreq times
+obj-$(CONFIG_CPU_FREQ_TIMES) += cpufreq_times.o
+
+# CPUfreq governors
obj-$(CONFIG_CPU_FREQ_GOV_PERFORMANCE) += cpufreq_performance.o
obj-$(CONFIG_CPU_FREQ_GOV_POWERSAVE) += cpufreq_powersave.o
obj-$(CONFIG_CPU_FREQ_GOV_USERSPACE) += cpufreq_userspace.o
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index f53fb41..98b5bac 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -19,6 +19,7 @@
#include <linux/cpu.h>
#include <linux/cpufreq.h>
+#include <linux/cpufreq_times.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/init.h>
@@ -349,6 +350,7 @@ static void cpufreq_notify_transition(struct cpufreq_policy *policy,
}
cpufreq_stats_record_transition(policy, freqs->new);
+ cpufreq_times_record_transition(freqs);
policy->cur = freqs->new;
}
}
@@ -1295,6 +1297,7 @@ static int cpufreq_online(unsigned int cpu)
goto out_destroy_policy;
cpufreq_stats_create_table(policy);
+ cpufreq_times_create_policy(policy);
write_lock_irqsave(&cpufreq_driver_lock, flags);
list_add(&policy->policy_list, &cpufreq_policy_list);
diff --git a/drivers/cpufreq/cpufreq_times.c b/drivers/cpufreq/cpufreq_times.c
new file mode 100644
index 0000000..339a3e9
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_times.c
@@ -0,0 +1,207 @@
+/* drivers/cpufreq/cpufreq_times.c
+ *
+ * Copyright (C) 2018 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/cpufreq.h>
+#include <linux/cpufreq_times.h>
+#include <linux/jiffies.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/threads.h>
+
+static DEFINE_SPINLOCK(task_time_in_state_lock); /* task->time_in_state */
+
+/**
+ * struct cpu_freqs - per-cpu frequency information
+ * @offset: start of these freqs' stats in task time_in_state array
+ * @max_state: number of entries in freq_table
+ * @last_index: index in freq_table of last frequency switched to
+ * @freq_table: list of available frequencies
+ */
+struct cpu_freqs {
+ unsigned int offset;
+ unsigned int max_state;
+ unsigned int last_index;
+ unsigned int freq_table[0];
+};
+
+static struct cpu_freqs *all_freqs[NR_CPUS];
+
+static unsigned int next_offset;
+
+void cpufreq_task_times_init(struct task_struct *p)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&task_time_in_state_lock, flags);
+ p->time_in_state = NULL;
+ spin_unlock_irqrestore(&task_time_in_state_lock, flags);
+ p->max_state = 0;
+}
+
+void cpufreq_task_times_alloc(struct task_struct *p)
+{
+ void *temp;
+ unsigned long flags;
+ unsigned int max_state = READ_ONCE(next_offset);
+
+ /* We use one array to avoid multiple allocs per task */
+ temp = kcalloc(max_state, sizeof(p->time_in_state[0]), GFP_ATOMIC);
+ if (!temp)
+ return;
+
+ spin_lock_irqsave(&task_time_in_state_lock, flags);
+ p->time_in_state = temp;
+ spin_unlock_irqrestore(&task_time_in_state_lock, flags);
+ p->max_state = max_state;
+}
+
+/* Caller must hold task_time_in_state_lock */
+static int cpufreq_task_times_realloc_locked(struct task_struct *p)
+{
+ void *temp;
+ unsigned int max_state = READ_ONCE(next_offset);
+
+ temp = krealloc(p->time_in_state, max_state * sizeof(u64), GFP_ATOMIC);
+ if (!temp)
+ return -ENOMEM;
+ p->time_in_state = temp;
+ memset(p->time_in_state + p->max_state, 0,
+ (max_state - p->max_state) * sizeof(u64));
+ p->max_state = max_state;
+ return 0;
+}
+
+void cpufreq_task_times_exit(struct task_struct *p)
+{
+ unsigned long flags;
+ void *temp;
+
+ spin_lock_irqsave(&task_time_in_state_lock, flags);
+ temp = p->time_in_state;
+ p->time_in_state = NULL;
+ spin_unlock_irqrestore(&task_time_in_state_lock, flags);
+ kfree(temp);
+}
+
+int proc_time_in_state_show(struct seq_file *m, struct pid_namespace *ns,
+ struct pid *pid, struct task_struct *p)
+{
+ unsigned int cpu, i;
+ u64 cputime;
+ unsigned long flags;
+ struct cpu_freqs *freqs;
+ struct cpu_freqs *last_freqs = NULL;
+
+ spin_lock_irqsave(&task_time_in_state_lock, flags);
+ for_each_possible_cpu(cpu) {
+ freqs = all_freqs[cpu];
+ if (!freqs || freqs == last_freqs)
+ continue;
+ last_freqs = freqs;
+
+ seq_printf(m, "cpu%u\n", cpu);
+ for (i = 0; i < freqs->max_state; i++) {
+ if (freqs->freq_table[i] == CPUFREQ_ENTRY_INVALID)
+ continue;
+ cputime = 0;
+ if (freqs->offset + i < p->max_state &&
+ p->time_in_state)
+ cputime = p->time_in_state[freqs->offset + i];
+ seq_printf(m, "%u %lu\n", freqs->freq_table[i],
+ (unsigned long)nsec_to_clock_t(cputime));
+ }
+ }
+ spin_unlock_irqrestore(&task_time_in_state_lock, flags);
+ return 0;
+}
+
+void cpufreq_acct_update_power(struct task_struct *p, u64 cputime)
+{
+ unsigned long flags;
+ unsigned int state;
+ struct cpu_freqs *freqs = all_freqs[task_cpu(p)];
+
+ if (!freqs || p->flags & PF_EXITING)
+ return;
+
+ state = freqs->offset + READ_ONCE(freqs->last_index);
+
+ spin_lock_irqsave(&task_time_in_state_lock, flags);
+ if ((state < p->max_state || !cpufreq_task_times_realloc_locked(p)) &&
+ p->time_in_state)
+ p->time_in_state[state] += cputime;
+ spin_unlock_irqrestore(&task_time_in_state_lock, flags);
+}
+
+void cpufreq_times_create_policy(struct cpufreq_policy *policy)
+{
+ int cpu, index;
+ unsigned int count = 0;
+ struct cpufreq_frequency_table *pos, *table;
+ struct cpu_freqs *freqs;
+ void *tmp;
+
+ if (all_freqs[policy->cpu])
+ return;
+
+ table = policy->freq_table;
+ if (!table)
+ return;
+
+ cpufreq_for_each_entry(pos, table)
+ count++;
+
+ tmp = kzalloc(sizeof(*freqs) + sizeof(freqs->freq_table[0]) * count,
+ GFP_KERNEL);
+ if (!tmp)
+ return;
+
+ freqs = tmp;
+ freqs->max_state = count;
+
+ index = cpufreq_frequency_table_get_index(policy, policy->cur);
+ if (index >= 0)
+ WRITE_ONCE(freqs->last_index, index);
+
+ cpufreq_for_each_entry(pos, table)
+ freqs->freq_table[pos - table] = pos->frequency;
+
+ freqs->offset = next_offset;
+ WRITE_ONCE(next_offset, freqs->offset + count);
+ for_each_cpu(cpu, policy->related_cpus)
+ all_freqs[cpu] = freqs;
+}
+
+void cpufreq_times_record_transition(struct cpufreq_freqs *freq)
+{
+ int index;
+ struct cpu_freqs *freqs = all_freqs[freq->cpu];
+ struct cpufreq_policy *policy;
+
+ if (!freqs)
+ return;
+
+ policy = cpufreq_cpu_get(freq->cpu);
+ if (!policy)
+ return;
+
+ index = cpufreq_frequency_table_get_index(policy, freq->new);
+ if (index >= 0)
+ WRITE_ONCE(freqs->last_index, index);
+
+ cpufreq_cpu_put(policy);
+}
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 7e9f07bf..b51e81e 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -94,6 +94,7 @@
#include <linux/sched/stat.h>
#include <linux/flex_array.h>
#include <linux/posix-timers.h>
+#include <linux/cpufreq_times.h>
#include <trace/events/oom.h>
#include "internal.h"
#include "fd.h"
@@ -3006,6 +3007,9 @@ static const struct pid_entry tgid_base_stuff[] = {
#ifdef CONFIG_LIVEPATCH
ONE("patch_state", S_IRUSR, proc_pid_patch_state),
#endif
+#ifdef CONFIG_CPU_FREQ_TIMES
+ ONE("time_in_state", 0444, proc_time_in_state_show),
+#endif
};
static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
@@ -3384,6 +3388,9 @@ static const struct pid_entry tid_base_stuff[] = {
#ifdef CONFIG_LIVEPATCH
ONE("patch_state", S_IRUSR, proc_pid_patch_state),
#endif
+#ifdef CONFIG_CPU_FREQ_TIMES
+ ONE("time_in_state", 0444, proc_time_in_state_show),
+#endif
};
static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
diff --git a/include/linux/cpufreq_times.h b/include/linux/cpufreq_times.h
new file mode 100644
index 0000000..bfef6e6
--- /dev/null
+++ b/include/linux/cpufreq_times.h
@@ -0,0 +1,41 @@
+/* drivers/cpufreq/cpufreq_times.c
+ *
+ * Copyright (C) 2018 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef _LINUX_CPUFREQ_TIMES_H
+#define _LINUX_CPUFREQ_TIMES_H
+
+#include <linux/cpufreq.h>
+#include <linux/pid.h>
+
+#ifdef CONFIG_CPU_FREQ_TIMES
+void cpufreq_task_times_init(struct task_struct *p);
+void cpufreq_task_times_alloc(struct task_struct *p);
+void cpufreq_task_times_exit(struct task_struct *p);
+int proc_time_in_state_show(struct seq_file *m, struct pid_namespace *ns,
+ struct pid *pid, struct task_struct *p);
+void cpufreq_acct_update_power(struct task_struct *p, u64 cputime);
+void cpufreq_times_create_policy(struct cpufreq_policy *policy);
+void cpufreq_times_record_transition(struct cpufreq_freqs *freq);
+#else
+static inline void cpufreq_task_times_init(struct task_struct *p) {}
+static inline void cpufreq_task_times_alloc(struct task_struct *p) {}
+static inline void cpufreq_task_times_exit(struct task_struct *p) {}
+static inline void cpufreq_acct_update_power(struct task_struct *p,
+ u64 cputime) {}
+static inline void cpufreq_times_create_policy(struct cpufreq_policy *policy) {}
+static inline void cpufreq_times_record_transition(
+ struct cpufreq_freqs *freq) {}
+#endif /* CONFIG_CPU_FREQ_TIMES */
+#endif /* _LINUX_CPUFREQ_TIMES_H */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 977cb57..97f4d64 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -799,6 +799,10 @@ struct task_struct {
u64 stimescaled;
#endif
u64 gtime;
+#ifdef CONFIG_CPU_FREQ_TIMES
+ u64 *time_in_state;
+ unsigned int max_state;
+#endif
struct prev_cputime prev_cputime;
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
struct vtime vtime;
diff --git a/kernel/fork.c b/kernel/fork.c
index f0b5847..65acaa2 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -91,6 +91,7 @@
#include <linux/kcov.h>
#include <linux/livepatch.h>
#include <linux/thread_info.h>
+#include <linux/cpufreq_times.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
@@ -394,6 +395,8 @@ void put_task_stack(struct task_struct *tsk)
void free_task(struct task_struct *tsk)
{
+ cpufreq_task_times_exit(tsk);
+
#ifndef CONFIG_THREAD_INFO_IN_TASK
/*
* The task is finally done with both the stack and thread_info,
@@ -1708,6 +1711,8 @@ static __latent_entropy struct task_struct *copy_process(
if (!p)
goto fork_out;
+ cpufreq_task_times_init(p);
+
/*
* This _must_ happen before we call free_task(), i.e. before we jump
* to any of the bad_fork_* labels. This is to avoid freeing
@@ -2170,6 +2175,8 @@ long _do_fork(unsigned long clone_flags,
if (IS_ERR(p))
return PTR_ERR(p);
+ cpufreq_task_times_alloc(p);
+
/*
* Do this prior waking up the new thread - the thread pointer
* might get invalid after that point, if the thread exits quickly.
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 0796f93..ca4208d 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -1,6 +1,7 @@
/*
* Simple CPU accounting cgroup controller
*/
+#include <linux/cpufreq_times.h>
#include "sched.h"
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -128,6 +129,9 @@ void account_user_time(struct task_struct *p, u64 cputime)
/* Account for user time used */
acct_account_cputime(p);
+
+ /* Account power usage for user time */
+ cpufreq_acct_update_power(p, cputime);
}
/*
@@ -172,6 +176,9 @@ void account_system_index_time(struct task_struct *p,
/* Account for system time used */
acct_account_cputime(p);
+
+ /* Account power usage for system time */
+ cpufreq_acct_update_power(p, cputime);
}
/*