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-rw-r--r--kernel/sched.c57
1 files changed, 51 insertions, 6 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index dcf2dc2..f04aa96 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -39,6 +39,7 @@
#include <linux/completion.h>
#include <linux/kernel_stat.h>
#include <linux/debug_locks.h>
+#include <linux/perf_counter.h>
#include <linux/security.h>
#include <linux/notifier.h>
#include <linux/profile.h>
@@ -579,6 +580,7 @@ struct rq {
struct load_weight load;
unsigned long nr_load_updates;
u64 nr_switches;
+ u64 nr_migrations_in;
struct cfs_rq cfs;
struct rt_rq rt;
@@ -691,7 +693,7 @@ static inline int cpu_of(struct rq *rq)
#define task_rq(p) cpu_rq(task_cpu(p))
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
-static inline void update_rq_clock(struct rq *rq)
+inline void update_rq_clock(struct rq *rq)
{
rq->clock = sched_clock_cpu(cpu_of(rq));
}
@@ -1968,12 +1970,16 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
p->se.sleep_start -= clock_offset;
if (p->se.block_start)
p->se.block_start -= clock_offset;
+#endif
if (old_cpu != new_cpu) {
- schedstat_inc(p, se.nr_migrations);
+ p->se.nr_migrations++;
+ new_rq->nr_migrations_in++;
+#ifdef CONFIG_SCHEDSTATS
if (task_hot(p, old_rq->clock, NULL))
schedstat_inc(p, se.nr_forced2_migrations);
- }
#endif
+ perf_counter_task_migration(p, new_cpu);
+ }
p->se.vruntime -= old_cfsrq->min_vruntime -
new_cfsrq->min_vruntime;
@@ -2368,6 +2374,27 @@ static int sched_balance_self(int cpu, int flag)
#endif /* CONFIG_SMP */
+/**
+ * task_oncpu_function_call - call a function on the cpu on which a task runs
+ * @p: the task to evaluate
+ * @func: the function to be called
+ * @info: the function call argument
+ *
+ * Calls the function @func when the task is currently running. This might
+ * be on the current CPU, which just calls the function directly
+ */
+void task_oncpu_function_call(struct task_struct *p,
+ void (*func) (void *info), void *info)
+{
+ int cpu;
+
+ preempt_disable();
+ cpu = task_cpu(p);
+ if (task_curr(p))
+ smp_call_function_single(cpu, func, info, 1);
+ preempt_enable();
+}
+
/***
* try_to_wake_up - wake up a thread
* @p: the to-be-woken-up thread
@@ -2535,6 +2562,7 @@ static void __sched_fork(struct task_struct *p)
p->se.exec_start = 0;
p->se.sum_exec_runtime = 0;
p->se.prev_sum_exec_runtime = 0;
+ p->se.nr_migrations = 0;
p->se.last_wakeup = 0;
p->se.avg_overlap = 0;
p->se.start_runtime = 0;
@@ -2765,6 +2793,7 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
*/
prev_state = prev->state;
finish_arch_switch(prev);
+ perf_counter_task_sched_in(current, cpu_of(rq));
finish_lock_switch(rq, prev);
#ifdef CONFIG_SMP
if (post_schedule)
@@ -2980,6 +3009,15 @@ static void calc_load_account_active(struct rq *this_rq)
}
/*
+ * Externally visible per-cpu scheduler statistics:
+ * cpu_nr_migrations(cpu) - number of migrations into that cpu
+ */
+u64 cpu_nr_migrations(int cpu)
+{
+ return cpu_rq(cpu)->nr_migrations_in;
+}
+
+/*
* Update rq->cpu_load[] statistics. This function is usually called every
* scheduler tick (TICK_NSEC).
*/
@@ -5077,6 +5115,8 @@ void scheduler_tick(void)
curr->sched_class->task_tick(rq, curr, 0);
spin_unlock(&rq->lock);
+ perf_counter_task_tick(curr, cpu);
+
#ifdef CONFIG_SMP
rq->idle_at_tick = idle_cpu(cpu);
trigger_load_balance(rq, cpu);
@@ -5292,6 +5332,7 @@ need_resched_nonpreemptible:
if (likely(prev != next)) {
sched_info_switch(prev, next);
+ perf_counter_task_sched_out(prev, next, cpu);
rq->nr_switches++;
rq->curr = next;
@@ -7535,8 +7576,10 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
return NOTIFY_OK;
}
-/* Register at highest priority so that task migration (migrate_all_tasks)
- * happens before everything else.
+/*
+ * Register at high priority so that task migration (migrate_all_tasks)
+ * happens before everything else. This has to be lower priority than
+ * the notifier in the perf_counter subsystem, though.
*/
static struct notifier_block __cpuinitdata migration_notifier = {
.notifier_call = migration_call,
@@ -9214,7 +9257,7 @@ void __init sched_init(void)
* 1024) and two child groups A0 and A1 (of weight 1024 each),
* then A0's share of the cpu resource is:
*
- * A0's bandwidth = 1024 / (10*1024 + 1024 + 1024) = 8.33%
+ * A0's bandwidth = 1024 / (10*1024 + 1024 + 1024) = 8.33%
*
* We achieve this by letting init_task_group's tasks sit
* directly in rq->cfs (i.e init_task_group->se[] = NULL).
@@ -9319,6 +9362,8 @@ void __init sched_init(void)
alloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
#endif /* SMP */
+ perf_counter_init();
+
scheduler_running = 1;
}