Hi,
thread topic was:
Re: [PATCH 3/4] scheduler: cpuacct: Enable platform callbacks for cpuacct power tracking
I mingled this patch together with a minor comment for Mike's patch.
Like this interested people in CC are kept.
Peter/Ingo: Can you pick up this cleanup if appropriate, please.
Shall I resend separately or could you cut out comments below?
On Wednesday 19 May 2010 03:30:19 Mike Chan wrote:
> Platform must register cpu power function that return power in
> milliWatt seconds.
>
> Signed-off-by: Mike Chan <mike@xxxxxxxxxxx>
> ---
> Documentation/cgroups/cpuacct.txt | 3 +++
> include/linux/cpuacct.h | 4 +++-
> kernel/sched.c | 24 ++++++++++++++++++++++--
> 3 files changed, 28 insertions(+), 3 deletions(-)
...
> diff --git a/include/linux/cpuacct.h b/include/linux/cpuacct.h
> index 9ff479e..effe842 100644
> --- a/include/linux/cpuacct.h
> +++ b/include/linux/cpuacct.h
> @@ -31,7 +31,9 @@ struct cpuacct_cpufreq_calls {
This is a general cpuacct_charge interface, not cpufreq specific?
I'd call it "struct cpuacct_charge_calls".
Platforms can account C-states, frequency, power, whatever they like?
The latter two are implemented with your patches.
> */
> void (*init) (void **cpuacct_data);
> void (*charge) (void *cpuacct_data, u64 cputime, unsigned int cpu);
> - void (*show) (void *cpuacct_data, struct cgroup_map_cb *cb);
> + void (*cpufreq_show) (void *cpuacct_data, struct cgroup_map_cb *cb);
> + /* Returns power consumed in milliWatt seconds */
> + u64 (*power_usage) (void *cpuacct_data);
> };
> int cpuacct_register_cpufreq(struct cpuacct_cpufreq_calls *fn);
Same here, why not name it cpuacct_register_charge?
Eventually at other places.
> diff --git a/kernel/sched.c b/kernel/sched.c
> index 6b6c45a..d55d8af 100644
> --- a/kernel/sched.c
> +++ b/kernel/sched.c
Nothing to do with this patch, but I wonder why this is all in kernel/sched.c.
Try a quick cleanup... works.
Whatabout below cleanup?
Not sure through which tree this should go in, but if below is accepted,
would you mind rebasing your things against it.
Then it would already show up in cgroup_cpuaccount.c git history.
Thomas
This is a cleanup against current linux-2.6 Linus tree.
Having CONFIG_CGROUP_CPUACCT code in kernel/sched.c looks wrong.
Move this out to kernel/cgroup_cpuaccount.c
Test compiled with and without CONFIG_CGROUP_CPUACCT set on x86_64.
Signed-off-by: Thomas Renninger <trenn@xxxxxxx>
CC: linux-kernel@xxxxxxxxxxxxxxx
CC: mike@xxxxxxxxxxx
CC: menage@xxxxxxxxxx
CC: lizf@xxxxxxxxxxxxxx
CC: containers@xxxxxxxxxxxxxxxxxxxxxxxxxx
CC: mingo@xxxxxxx
CC: peterz@xxxxxxxxxxxxx
---
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 8f78073..6e2c88a 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -609,6 +609,24 @@ bool css_is_ancestor(struct cgroup_subsys_state *cg,
unsigned short css_id(struct cgroup_subsys_state *css);
unsigned short css_depth(struct cgroup_subsys_state *css);
+/* Time spent by the tasks of the cpu accounting group executing in ... */
+enum cpuacct_stat_index {
+ CPUACCT_STAT_USER, /* ... user mode */
+ CPUACCT_STAT_SYSTEM, /* ... kernel mode */
+
+ CPUACCT_STAT_NSTATS,
+};
+
+#ifdef CONFIG_CGROUP_CPUACCT
+void cpuacct_charge(struct task_struct *tsk, u64 cputime);
+void cpuacct_update_stats(struct task_struct *tsk,
+ enum cpuacct_stat_index idx, cputime_t val);
+#else
+static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
+static inline void cpuacct_update_stats(struct task_struct *tsk,
+ enum cpuacct_stat_index idx, cputime_t val) {}
+#endif
+
#else /* !CONFIG_CGROUPS */
static inline int cgroup_init_early(void) { return 0; }
diff --git a/kernel/Makefile b/kernel/Makefile
index 149e18e..1df6e53 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
obj-$(CONFIG_COMPAT) += compat.o
obj-$(CONFIG_CGROUPS) += cgroup.o
+obj-$(CONFIG_CGROUP_CPUACCT) += cgroup_cpuaccount.o
obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
obj-$(CONFIG_CPUSETS) += cpuset.o
obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o
diff --git a/kernel/cgroup_cpuaccount.c b/kernel/cgroup_cpuaccount.c
new file mode 100644
index 0000000..d32b927
--- /dev/null
+++ b/kernel/cgroup_cpuaccount.c
@@ -0,0 +1,284 @@
+#include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include <linux/cgroup.h>
+#include <linux/srcu.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+
+#include <asm/cputime.h>
+
+/*
+ * CPU accounting code for task groups.
+ *
+ * Based on the work by Paul Menage (menage@xxxxxxxxxx) and Balbir Singh
+ * (balbir@xxxxxxxxxx).
+ */
+
+/* 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 percpu_counter cpustat[CPUACCT_STAT_NSTATS];
+ struct cpuacct *parent;
+};
+
+struct cgroup_subsys cpuacct_subsys;
+
+/* return cpu accounting group corresponding to this container */
+static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp)
+{
+ return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id),
+ struct cpuacct, css);
+}
+
+/* return cpu accounting group to which this task belongs */
+static inline struct cpuacct *task_ca(struct task_struct *tsk)
+{
+ return container_of(task_subsys_state(tsk, cpuacct_subsys_id),
+ struct cpuacct, css);
+}
+
+/* create a new cpu accounting group */
+static struct cgroup_subsys_state *cpuacct_create(
+ struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+ struct cpuacct *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
+ int i;
+
+ if (!ca)
+ goto out;
+
+ ca->cpuusage = alloc_percpu(u64);
+ if (!ca->cpuusage)
+ goto out_free_ca;
+
+ for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
+ if (percpu_counter_init(&ca->cpustat[i], 0))
+ goto out_free_counters;
+
+ if (cgrp->parent)
+ ca->parent = cgroup_ca(cgrp->parent);
+
+ return &ca->css;
+
+out_free_counters:
+ while (--i >= 0)
+ percpu_counter_destroy(&ca->cpustat[i]);
+ free_percpu(ca->cpuusage);
+out_free_ca:
+ kfree(ca);
+out:
+ return ERR_PTR(-ENOMEM);
+}
+
+/* destroy an existing cpu accounting group */
+static void
+cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+ struct cpuacct *ca = cgroup_ca(cgrp);
+ int i;
+
+ for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
+ percpu_counter_destroy(&ca->cpustat[i]);
+ free_percpu(ca->cpuusage);
+ kfree(ca);
+}
+
+static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
+{
+ u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ u64 data;
+
+#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;
+ raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
+#else
+ data = *cpuusage;
+#endif
+
+ return data;
+}
+
+static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
+{
+ u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+
+#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;
+ 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 *cgrp, struct cftype *cft)
+{
+ struct cpuacct *ca = cgroup_ca(cgrp);
+ u64 totalcpuusage = 0;
+ int i;
+
+ for_each_present_cpu(i)
+ totalcpuusage += cpuacct_cpuusage_read(ca, i);
+
+ return totalcpuusage;
+}
+
+static int cpuusage_write(struct cgroup *cgrp, struct cftype *cftype,
+ u64 reset)
+{
+ struct cpuacct *ca = cgroup_ca(cgrp);
+ int err = 0;
+ int i;
+
+ if (reset) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ for_each_present_cpu(i)
+ cpuacct_cpuusage_write(ca, i, 0);
+
+out:
+ return err;
+}
+
+static int cpuacct_percpu_seq_read(struct cgroup *cgroup, struct cftype *cft,
+ struct seq_file *m)
+{
+ struct cpuacct *ca = cgroup_ca(cgroup);
+ u64 percpu;
+ int i;
+
+ for_each_present_cpu(i) {
+ percpu = cpuacct_cpuusage_read(ca, i);
+ seq_printf(m, "%llu ", (unsigned long long) percpu);
+ }
+ seq_printf(m, "\n");
+ return 0;
+}
+
+static const char *cpuacct_stat_desc[] = {
+ [CPUACCT_STAT_USER] = "user",
+ [CPUACCT_STAT_SYSTEM] = "system",
+};
+
+static int cpuacct_stats_show(struct cgroup *cgrp, struct cftype *cft,
+ struct cgroup_map_cb *cb)
+{
+ struct cpuacct *ca = cgroup_ca(cgrp);
+ int i;
+
+ for (i = 0; i < CPUACCT_STAT_NSTATS; i++) {
+ s64 val = percpu_counter_read(&ca->cpustat[i]);
+ val = cputime64_to_clock_t(val);
+ cb->fill(cb, cpuacct_stat_desc[i], val);
+ }
+ return 0;
+}
+
+static struct cftype files[] = {
+ {
+ .name = "usage",
+ .read_u64 = cpuusage_read,
+ .write_u64 = cpuusage_write,
+ },
+ {
+ .name = "usage_percpu",
+ .read_seq_string = cpuacct_percpu_seq_read,
+ },
+ {
+ .name = "stat",
+ .read_map = cpuacct_stats_show,
+ },
+};
+
+static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+ return cgroup_add_files(cgrp, ss, files, ARRAY_SIZE(files));
+}
+
+/*
+ * charge this task's execution time to its accounting group.
+ *
+ * called with rq->lock held.
+ */
+void cpuacct_charge(struct task_struct *tsk, u64 cputime)
+{
+ struct cpuacct *ca;
+ int cpu;
+
+ if (unlikely(!cpuacct_subsys.active))
+ return;
+
+ cpu = task_cpu(tsk);
+
+ rcu_read_lock();
+
+ ca = task_ca(tsk);
+
+ for (; ca; ca = ca->parent) {
+ u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ *cpuusage += cputime;
+ }
+
+ rcu_read_unlock();
+}
+
+/*
+ * When CONFIG_VIRT_CPU_ACCOUNTING is enabled one jiffy can be very large
+ * in cputime_t units. As a result, cpuacct_update_stats calls
+ * percpu_counter_add with values large enough to always overflow the
+ * per cpu batch limit causing bad SMP scalability.
+ *
+ * To fix this we scale percpu_counter_batch by cputime_one_jiffy so we
+ * batch the same amount of time with CONFIG_VIRT_CPU_ACCOUNTING disabled
+ * and enabled. We cap it at INT_MAX which is the largest allowed batch value.
+ */
+#ifdef CONFIG_SMP
+#define CPUACCT_BATCH \
+ min_t(long, percpu_counter_batch * cputime_one_jiffy, INT_MAX)
+#else
+#define CPUACCT_BATCH 0
+#endif
+
+/*
+ * Charge the system/user time to the task's accounting group.
+ */
+void cpuacct_update_stats(struct task_struct *tsk,
+ enum cpuacct_stat_index idx, cputime_t val)
+{
+ struct cpuacct *ca;
+ int batch = CPUACCT_BATCH;
+
+ if (unlikely(!cpuacct_subsys.active))
+ return;
+
+ rcu_read_lock();
+ ca = task_ca(tsk);
+
+ do {
+ __percpu_counter_add(&ca->cpustat[idx], val, batch);
+ ca = ca->parent;
+ } while (ca);
+ rcu_read_unlock();
+}
+
+struct cgroup_subsys cpuacct_subsys = {
+ .name = "cpuacct",
+ .create = cpuacct_create,
+ .destroy = cpuacct_destroy,
+ .populate = cpuacct_populate,
+ .subsys_id = cpuacct_subsys_id,
+};
diff --git a/kernel/sched.c b/kernel/sched.c
index 1d93cd0..45d60dd 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1394,24 +1394,6 @@ static const u32 prio_to_wmult[40] = {
/* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
};
-/* Time spent by the tasks of the cpu accounting group executing in ... */
-enum cpuacct_stat_index {
- CPUACCT_STAT_USER, /* ... user mode */
- CPUACCT_STAT_SYSTEM, /* ... kernel mode */
-
- CPUACCT_STAT_NSTATS,
-};
-
-#ifdef CONFIG_CGROUP_CPUACCT
-static void cpuacct_charge(struct task_struct *tsk, u64 cputime);
-static void cpuacct_update_stats(struct task_struct *tsk,
- enum cpuacct_stat_index idx, cputime_t val);
-#else
-static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
-static inline void cpuacct_update_stats(struct task_struct *tsk,
- enum cpuacct_stat_index idx, cputime_t val) {}
-#endif
-
static inline void inc_cpu_load(struct rq *rq, unsigned long load)
{
update_load_add(&rq->load, load);
@@ -8617,283 +8599,6 @@ struct cgroup_subsys cpu_cgroup_subsys = {
#endif /* CONFIG_CGROUP_SCHED */
-#ifdef CONFIG_CGROUP_CPUACCT
-
-/*
- * CPU accounting code for task groups.
- *
- * Based on the work by Paul Menage (menage@xxxxxxxxxx) and Balbir Singh
- * (balbir@xxxxxxxxxx).
- */
-
-/* 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 percpu_counter cpustat[CPUACCT_STAT_NSTATS];
- struct cpuacct *parent;
-};
-
-struct cgroup_subsys cpuacct_subsys;
-
-/* return cpu accounting group corresponding to this container */
-static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp)
-{
- return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id),
- struct cpuacct, css);
-}
-
-/* return cpu accounting group to which this task belongs */
-static inline struct cpuacct *task_ca(struct task_struct *tsk)
-{
- return container_of(task_subsys_state(tsk, cpuacct_subsys_id),
- struct cpuacct, css);
-}
-
-/* create a new cpu accounting group */
-static struct cgroup_subsys_state *cpuacct_create(
- struct cgroup_subsys *ss, struct cgroup *cgrp)
-{
- struct cpuacct *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
- int i;
-
- if (!ca)
- goto out;
-
- ca->cpuusage = alloc_percpu(u64);
- if (!ca->cpuusage)
- goto out_free_ca;
-
- for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
- if (percpu_counter_init(&ca->cpustat[i], 0))
- goto out_free_counters;
-
- if (cgrp->parent)
- ca->parent = cgroup_ca(cgrp->parent);
-
- return &ca->css;
-
-out_free_counters:
- while (--i >= 0)
- percpu_counter_destroy(&ca->cpustat[i]);
- free_percpu(ca->cpuusage);
-out_free_ca:
- kfree(ca);
-out:
- return ERR_PTR(-ENOMEM);
-}
-
-/* destroy an existing cpu accounting group */
-static void
-cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
-{
- struct cpuacct *ca = cgroup_ca(cgrp);
- int i;
-
- for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
- percpu_counter_destroy(&ca->cpustat[i]);
- free_percpu(ca->cpuusage);
- kfree(ca);
-}
-
-static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
-{
- u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
- u64 data;
-
-#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;
- raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
-#else
- data = *cpuusage;
-#endif
-
- return data;
-}
-
-static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
-{
- u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
-
-#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;
- 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 *cgrp, struct cftype *cft)
-{
- struct cpuacct *ca = cgroup_ca(cgrp);
- u64 totalcpuusage = 0;
- int i;
-
- for_each_present_cpu(i)
- totalcpuusage += cpuacct_cpuusage_read(ca, i);
-
- return totalcpuusage;
-}
-
-static int cpuusage_write(struct cgroup *cgrp, struct cftype *cftype,
- u64 reset)
-{
- struct cpuacct *ca = cgroup_ca(cgrp);
- int err = 0;
- int i;
-
- if (reset) {
- err = -EINVAL;
- goto out;
- }
-
- for_each_present_cpu(i)
- cpuacct_cpuusage_write(ca, i, 0);
-
-out:
- return err;
-}
-
-static int cpuacct_percpu_seq_read(struct cgroup *cgroup, struct cftype *cft,
- struct seq_file *m)
-{
- struct cpuacct *ca = cgroup_ca(cgroup);
- u64 percpu;
- int i;
-
- for_each_present_cpu(i) {
- percpu = cpuacct_cpuusage_read(ca, i);
- seq_printf(m, "%llu ", (unsigned long long) percpu);
- }
- seq_printf(m, "\n");
- return 0;
-}
-
-static const char *cpuacct_stat_desc[] = {
- [CPUACCT_STAT_USER] = "user",
- [CPUACCT_STAT_SYSTEM] = "system",
-};
-
-static int cpuacct_stats_show(struct cgroup *cgrp, struct cftype *cft,
- struct cgroup_map_cb *cb)
-{
- struct cpuacct *ca = cgroup_ca(cgrp);
- int i;
-
- for (i = 0; i < CPUACCT_STAT_NSTATS; i++) {
- s64 val = percpu_counter_read(&ca->cpustat[i]);
- val = cputime64_to_clock_t(val);
- cb->fill(cb, cpuacct_stat_desc[i], val);
- }
- return 0;
-}
-
-static struct cftype files[] = {
- {
- .name = "usage",
- .read_u64 = cpuusage_read,
- .write_u64 = cpuusage_write,
- },
- {
- .name = "usage_percpu",
- .read_seq_string = cpuacct_percpu_seq_read,
- },
- {
- .name = "stat",
- .read_map = cpuacct_stats_show,
- },
-};
-
-static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
-{
- return cgroup_add_files(cgrp, ss, files, ARRAY_SIZE(files));
-}
-
-/*
- * charge this task's execution time to its accounting group.
- *
- * called with rq->lock held.
- */
-static void cpuacct_charge(struct task_struct *tsk, u64 cputime)
-{
- struct cpuacct *ca;
- int cpu;
-
- if (unlikely(!cpuacct_subsys.active))
- return;
-
- cpu = task_cpu(tsk);
-
- rcu_read_lock();
-
- ca = task_ca(tsk);
-
- for (; ca; ca = ca->parent) {
- u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
- *cpuusage += cputime;
- }
-
- rcu_read_unlock();
-}
-
-/*
- * When CONFIG_VIRT_CPU_ACCOUNTING is enabled one jiffy can be very large
- * in cputime_t units. As a result, cpuacct_update_stats calls
- * percpu_counter_add with values large enough to always overflow the
- * per cpu batch limit causing bad SMP scalability.
- *
- * To fix this we scale percpu_counter_batch by cputime_one_jiffy so we
- * batch the same amount of time with CONFIG_VIRT_CPU_ACCOUNTING disabled
- * and enabled. We cap it at INT_MAX which is the largest allowed batch value.
- */
-#ifdef CONFIG_SMP
-#define CPUACCT_BATCH \
- min_t(long, percpu_counter_batch * cputime_one_jiffy, INT_MAX)
-#else
-#define CPUACCT_BATCH 0
-#endif
-
-/*
- * Charge the system/user time to the task's accounting group.
- */
-static void cpuacct_update_stats(struct task_struct *tsk,
- enum cpuacct_stat_index idx, cputime_t val)
-{
- struct cpuacct *ca;
- int batch = CPUACCT_BATCH;
-
- if (unlikely(!cpuacct_subsys.active))
- return;
-
- rcu_read_lock();
- ca = task_ca(tsk);
-
- do {
- __percpu_counter_add(&ca->cpustat[idx], val, batch);
- ca = ca->parent;
- } while (ca);
- rcu_read_unlock();
-}
-
-struct cgroup_subsys cpuacct_subsys = {
- .name = "cpuacct",
- .create = cpuacct_create,
- .destroy = cpuacct_destroy,
- .populate = cpuacct_populate,
- .subsys_id = cpuacct_subsys_id,
-};
-#endif /* CONFIG_CGROUP_CPUACCT */
-
#ifndef CONFIG_SMP
void synchronize_sched_expedited(void)
--
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