tools headers UAPI: Synch KVM's svm.h header with the kernel

[linux-2.6-microblaze.git] / kernel / delayacct.c

diff --git a/kernel/delayacct.c b/kernel/delayacct.c
index 2772575..51530d5 100644 (file)
--- a/kernel/delayacct.c
+++ b/kernel/delayacct.c
@@ -7,30 +7,64 @@
 #include <linux/sched.h>
 #include <linux/sched/task.h>
 #include <linux/sched/cputime.h>
+#include <linux/sched/clock.h>
 #include <linux/slab.h>
 #include <linux/taskstats.h>
-#include <linux/time.h>
 #include <linux/sysctl.h>
 #include <linux/delayacct.h>
 #include <linux/module.h>
 
-int delayacct_on __read_mostly = 1;    /* Delay accounting turned on/off */
-EXPORT_SYMBOL_GPL(delayacct_on);
+DEFINE_STATIC_KEY_FALSE(delayacct_key);
+int delayacct_on __read_mostly;        /* Delay accounting turned on/off */
 struct kmem_cache *delayacct_cache;
 
-static int __init delayacct_setup_disable(char *str)
+static void set_delayacct(bool enabled)
 {
-       delayacct_on = 0;
+       if (enabled) {
+               static_branch_enable(&delayacct_key);
+               delayacct_on = 1;
+       } else {
+               delayacct_on = 0;
+               static_branch_disable(&delayacct_key);
+       }
+}
+
+static int __init delayacct_setup_enable(char *str)
+{
+       delayacct_on = 1;
        return 1;
 }
-__setup("nodelayacct", delayacct_setup_disable);
+__setup("delayacct", delayacct_setup_enable);
 
 void delayacct_init(void)
 {
        delayacct_cache = KMEM_CACHE(task_delay_info, SLAB_PANIC|SLAB_ACCOUNT);
        delayacct_tsk_init(&init_task);
+       set_delayacct(delayacct_on);
 }
 
+#ifdef CONFIG_PROC_SYSCTL
+int sysctl_delayacct(struct ctl_table *table, int write, void *buffer,
+                    size_t *lenp, loff_t *ppos)
+{
+       int state = delayacct_on;
+       struct ctl_table t;
+       int err;
+
+       if (write && !capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
+       t = *table;
+       t.data = &state;
+       err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos);
+       if (err < 0)
+               return err;
+       if (write)
+               set_delayacct(state);
+       return err;
+}
+#endif
+
 void __delayacct_tsk_init(struct task_struct *tsk)
 {
        tsk->delays = kmem_cache_zalloc(delayacct_cache, GFP_KERNEL);
@@ -42,10 +76,9 @@ void __delayacct_tsk_init(struct task_struct *tsk)
  * Finish delay accounting for a statistic using its timestamps (@start),
  * accumalator (@total) and @count
  */
-static void delayacct_end(raw_spinlock_t *lock, u64 *start, u64 *total,
-                         u32 *count)
+static void delayacct_end(raw_spinlock_t *lock, u64 *start, u64 *total, u32 *count)
 {
-       s64 ns = ktime_get_ns() - *start;
+       s64 ns = local_clock() - *start;
        unsigned long flags;
 
        if (ns > 0) {
@@ -58,7 +91,7 @@ static void delayacct_end(raw_spinlock_t *lock, u64 *start, u64 *total,
 
 void __delayacct_blkio_start(void)
 {
-       current->delays->blkio_start = ktime_get_ns();
+       current->delays->blkio_start = local_clock();
 }
 
 /*
@@ -82,7 +115,7 @@ void __delayacct_blkio_end(struct task_struct *p)
        delayacct_end(&delays->lock, &delays->blkio_start, total, count);
 }
 
-int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk)
+int delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk)
 {
        u64 utime, stime, stimescaled, utimescaled;
        unsigned long long t2, t3;
@@ -117,6 +150,9 @@ int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk)
        d->cpu_run_virtual_total =
                (tmp < (s64)d->cpu_run_virtual_total) ? 0 : tmp;
 
+       if (!tsk->delays)
+               return 0;
+
        /* zero XXX_total, non-zero XXX_count implies XXX stat overflowed */
 
        raw_spin_lock_irqsave(&tsk->delays->lock, flags);
@@ -151,21 +187,20 @@ __u64 __delayacct_blkio_ticks(struct task_struct *tsk)
 
 void __delayacct_freepages_start(void)
 {
-       current->delays->freepages_start = ktime_get_ns();
+       current->delays->freepages_start = local_clock();
 }
 
 void __delayacct_freepages_end(void)
 {
-       delayacct_end(
-               &current->delays->lock,
-               &current->delays->freepages_start,
-               &current->delays->freepages_delay,
-               &current->delays->freepages_count);
+       delayacct_end(&current->delays->lock,
+                     &current->delays->freepages_start,
+                     &current->delays->freepages_delay,
+                     &current->delays->freepages_count);
 }
 
 void __delayacct_thrashing_start(void)
 {
-       current->delays->thrashing_start = ktime_get_ns();
+       current->delays->thrashing_start = local_clock();
 }
 
 void __delayacct_thrashing_end(void)