[tip:sched/core] sched/cpuacct: Split usage accounting into user_usage and sys_usage
From: tip-bot for Dongsheng Yang
Date: Thu Mar 31 2016 - 05:28:33 EST
Commit-ID: d740037fac7052e49450f6fa1454f1144a103b55
Gitweb: http://git.kernel.org/tip/d740037fac7052e49450f6fa1454f1144a103b55
Author: Dongsheng Yang <yangds.fnst@xxxxxxxxxxxxxx>
AuthorDate: Tue, 22 Mar 2016 16:37:08 +0800
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 31 Mar 2016 10:48:54 +0200
sched/cpuacct: Split usage accounting into user_usage and sys_usage
Sometimes, cpuacct.usage is not detailed enough to see how much CPU
usage a group had. We want to know how much time it used in user mode
and how much in kernel mode.
This patch introduces more files to give this information:
# ls /sys/fs/cgroup/cpuacct/cpuacct.usage*
/sys/fs/cgroup/cpuacct/cpuacct.usage
/sys/fs/cgroup/cpuacct/cpuacct.usage_percpu
/sys/fs/cgroup/cpuacct/cpuacct.usage_user
/sys/fs/cgroup/cpuacct/cpuacct.usage_percpu_user
/sys/fs/cgroup/cpuacct/cpuacct.usage_sys
/sys/fs/cgroup/cpuacct/cpuacct.usage_percpu_sys
... while keeping the ABI with the existing counter.
Signed-off-by: Dongsheng Yang <yangds.fnst@xxxxxxxxxxxxxx>
[ Ported to newer kernels. ]
Signed-off-by: Zhao Lei <zhaolei@xxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Tejun Heo <htejun@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/aa171da036b520b51c79549e9b3215d29473f19d.1458635566.git.zhaolei@xxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
kernel/sched/cpuacct.c | 140 +++++++++++++++++++++++++++++++++++++++----------
1 file changed, 113 insertions(+), 27 deletions(-)
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index e39bd4f..df947e0 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -25,11 +25,22 @@ enum cpuacct_stat_index {
CPUACCT_STAT_NSTATS,
};
+enum cpuacct_usage_index {
+ CPUACCT_USAGE_USER, /* ... user mode */
+ CPUACCT_USAGE_SYSTEM, /* ... kernel mode */
+
+ CPUACCT_USAGE_NRUSAGE,
+};
+
+struct cpuacct_usage {
+ u64 usages[CPUACCT_USAGE_NRUSAGE];
+};
+
/* track cpu usage of a group of tasks and its child groups */
struct cpuacct {
struct cgroup_subsys_state css;
/* cpuusage holds pointer to a u64-type object on every cpu */
- u64 __percpu *cpuusage;
+ struct cpuacct_usage __percpu *cpuusage;
struct kernel_cpustat __percpu *cpustat;
};
@@ -49,7 +60,7 @@ static inline struct cpuacct *parent_ca(struct cpuacct *ca)
return css_ca(ca->css.parent);
}
-static DEFINE_PER_CPU(u64, root_cpuacct_cpuusage);
+static DEFINE_PER_CPU(struct cpuacct_usage, root_cpuacct_cpuusage);
static struct cpuacct root_cpuacct = {
.cpustat = &kernel_cpustat,
.cpuusage = &root_cpuacct_cpuusage,
@@ -68,7 +79,7 @@ cpuacct_css_alloc(struct cgroup_subsys_state *parent_css)
if (!ca)
goto out;
- ca->cpuusage = alloc_percpu(u64);
+ ca->cpuusage = alloc_percpu(struct cpuacct_usage);
if (!ca->cpuusage)
goto out_free_ca;
@@ -96,20 +107,37 @@ static void cpuacct_css_free(struct cgroup_subsys_state *css)
kfree(ca);
}
-static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
+static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu,
+ enum cpuacct_usage_index index)
{
- u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
u64 data;
+ /*
+ * We allow index == CPUACCT_USAGE_NRUSAGE here to read
+ * the sum of suages.
+ */
+ BUG_ON(index > CPUACCT_USAGE_NRUSAGE);
+
#ifndef CONFIG_64BIT
/*
* Take rq->lock to make 64-bit read safe on 32-bit platforms.
*/
raw_spin_lock_irq(&cpu_rq(cpu)->lock);
- data = *cpuusage;
+#endif
+
+ if (index == CPUACCT_USAGE_NRUSAGE) {
+ int i = 0;
+
+ data = 0;
+ for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++)
+ data += cpuusage->usages[i];
+ } else {
+ data = cpuusage->usages[index];
+ }
+
+#ifndef CONFIG_64BIT
raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
-#else
- data = *cpuusage;
#endif
return data;
@@ -117,69 +145,103 @@ static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
{
- u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ int i;
#ifndef CONFIG_64BIT
/*
* Take rq->lock to make 64-bit write safe on 32-bit platforms.
*/
raw_spin_lock_irq(&cpu_rq(cpu)->lock);
- *cpuusage = val;
+#endif
+
+ for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++)
+ cpuusage->usages[i] = val;
+
+#ifndef CONFIG_64BIT
raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
-#else
- *cpuusage = val;
#endif
}
/* return total cpu usage (in nanoseconds) of a group */
-static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
+static u64 __cpuusage_read(struct cgroup_subsys_state *css,
+ enum cpuacct_usage_index index)
{
struct cpuacct *ca = css_ca(css);
u64 totalcpuusage = 0;
int i;
for_each_possible_cpu(i)
- totalcpuusage += cpuacct_cpuusage_read(ca, i);
+ totalcpuusage += cpuacct_cpuusage_read(ca, i, index);
return totalcpuusage;
}
+static u64 cpuusage_user_read(struct cgroup_subsys_state *css,
+ struct cftype *cft)
+{
+ return __cpuusage_read(css, CPUACCT_USAGE_USER);
+}
+
+static u64 cpuusage_sys_read(struct cgroup_subsys_state *css,
+ struct cftype *cft)
+{
+ return __cpuusage_read(css, CPUACCT_USAGE_SYSTEM);
+}
+
+static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
+{
+ return __cpuusage_read(css, CPUACCT_USAGE_NRUSAGE);
+}
+
static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
u64 val)
{
struct cpuacct *ca = css_ca(css);
- int err = 0;
- int i;
+ int cpu;
/*
* Only allow '0' here to do a reset.
*/
- if (val) {
- err = -EINVAL;
- goto out;
- }
+ if (val)
+ return -EINVAL;
- for_each_possible_cpu(i)
- cpuacct_cpuusage_write(ca, i, 0);
+ for_each_possible_cpu(cpu)
+ cpuacct_cpuusage_write(ca, cpu, 0);
-out:
- return err;
+ return 0;
}
-static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
+static int __cpuacct_percpu_seq_show(struct seq_file *m,
+ enum cpuacct_usage_index index)
{
struct cpuacct *ca = css_ca(seq_css(m));
u64 percpu;
int i;
for_each_possible_cpu(i) {
- percpu = cpuacct_cpuusage_read(ca, i);
+ percpu = cpuacct_cpuusage_read(ca, i, index);
seq_printf(m, "%llu ", (unsigned long long) percpu);
}
seq_printf(m, "\n");
return 0;
}
+static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V)
+{
+ return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_USER);
+}
+
+static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V)
+{
+ return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_SYSTEM);
+}
+
+static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
+{
+ return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_NRUSAGE);
+}
+
static const char * const cpuacct_stat_desc[] = {
[CPUACCT_STAT_USER] = "user",
[CPUACCT_STAT_SYSTEM] = "system",
@@ -220,10 +282,26 @@ static struct cftype files[] = {
.write_u64 = cpuusage_write,
},
{
+ .name = "usage_user",
+ .read_u64 = cpuusage_user_read,
+ },
+ {
+ .name = "usage_sys",
+ .read_u64 = cpuusage_sys_read,
+ },
+ {
.name = "usage_percpu",
.seq_show = cpuacct_percpu_seq_show,
},
{
+ .name = "usage_percpu_user",
+ .seq_show = cpuacct_percpu_user_seq_show,
+ },
+ {
+ .name = "usage_percpu_sys",
+ .seq_show = cpuacct_percpu_sys_seq_show,
+ },
+ {
.name = "stat",
.seq_show = cpuacct_stats_show,
},
@@ -238,10 +316,18 @@ static struct cftype files[] = {
void cpuacct_charge(struct task_struct *tsk, u64 cputime)
{
struct cpuacct *ca;
+ int index;
+
+ if (user_mode(task_pt_regs(tsk)))
+ index = CPUACCT_USAGE_USER;
+ else
+ index = CPUACCT_USAGE_SYSTEM;
rcu_read_lock();
+
for (ca = task_ca(tsk); ca; ca = parent_ca(ca))
- *this_cpu_ptr(ca->cpuusage) += cputime;
+ this_cpu_ptr(ca->cpuusage)->usages[index] += cputime;
+
rcu_read_unlock();
}