2 files changed, 39 insertions, 36 deletions

diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index ea0ea1a4c36f..e752d973fa21 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -48,12 +48,11 @@ extern struct fs_struct init_fs;
         .posix_timers    = LIST_HEAD_INIT(sig.posix_timers),            \
         .cpu_timers     = INIT_CPU_TIMERS(sig.cpu_timers),              \
         .rlim           = INIT_RLIMITS,                                 \
-        .cputime        = { .totals = {                                 \
-                .utime = cputime_zero,                                  \
-                .stime = cputime_zero,                                  \
-                .sum_exec_runtime = 0,                                  \
-                .lock = __SPIN_LOCK_UNLOCKED(sig.cputime.totals.lock),  \
-        }, },                                                           \
+        .cputimer       = {                                             \
+                .cputime = INIT_CPUTIME,                                \
+                .running = 0,                                           \
+                .lock = __SPIN_LOCK_UNLOCKED(sig.cputimer.lock),        \
+        },                                                              \
 }
 
 extern struct nsproxy init_nsproxy;
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 2127e959e0f4..8981e52c714f 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -443,7 +443,6 @@ struct pacct_struct {
  * @utime:              time spent in user mode, in &cputime_t units
  * @stime:              time spent in kernel mode, in &cputime_t units
  * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
- * @lock:               lock for fields in this struct
  *
  * This structure groups together three kinds of CPU time that are
  * tracked for threads and thread groups.  Most things considering
@@ -454,23 +453,33 @@ struct task_cputime {
         cputime_t utime;
         cputime_t stime;
         unsigned long long sum_exec_runtime;
-        spinlock_t lock;
 };
 /* Alternate field names when used to cache expirations. */
 #define prof_exp        stime
 #define virt_exp        utime
 #define sched_exp       sum_exec_runtime
 
+#define INIT_CPUTIME    \
+        (struct task_cputime) {                                 \
+                .utime = cputime_zero,                          \
+                .stime = cputime_zero,                          \
+                .sum_exec_runtime = 0,                          \
+        }
+
 /**
- * struct thread_group_cputime - thread group interval timer counts
- * @totals:             thread group interval timers; substructure for
- *                      uniprocessor kernel, per-cpu for SMP kernel.
+ * struct thread_group_cputimer - thread group interval timer counts
+ * @cputime:            thread group interval timers.
+ * @running:            non-zero when there are timers running and
+ *                      @cputime receives updates.
+ * @lock:               lock for fields in this struct.
  *
  * This structure contains the version of task_cputime, above, that is
- * used for thread group CPU clock calculations.
+ * used for thread group CPU timer calculations.
  */
-struct thread_group_cputime {
-        struct task_cputime totals;
+struct thread_group_cputimer {
+        struct task_cputime cputime;
+        int running;
+        spinlock_t lock;
 };
 
 /*
@@ -519,10 +528,10 @@ struct signal_struct {
         cputime_t it_prof_incr, it_virt_incr;
 
         /*
-         * Thread group totals for process CPU clocks.
-         * See thread_group_cputime(), et al, for details.
+         * Thread group totals for process CPU timers.
+         * See thread_group_cputimer(), et al, for details.
          */
-        struct thread_group_cputime cputime;
+        struct thread_group_cputimer cputimer;
 
         /* Earliest-expiration cache. */
         struct task_cputime cputime_expires;
@@ -559,7 +568,7 @@ struct signal_struct {
          * Live threads maintain their own counters and add to these
          * in __exit_signal, except for the group leader.
          */
-        cputime_t cutime, cstime;
+        cputime_t utime, stime, cutime, cstime;
         cputime_t gtime;
         cputime_t cgtime;
         unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
@@ -568,6 +577,14 @@ struct signal_struct {
         struct task_io_accounting ioac;
 
         /*
+         * Cumulative ns of schedule CPU time fo dead threads in the
+         * group, not including a zombie group leader, (This only differs
+         * from jiffies_to_ns(utime + stime) if sched_clock uses something
+         * other than jiffies.)
+         */
+        unsigned long long sum_sched_runtime;
+
+        /*
          * We don't bother to synchronize most readers of this at all,
          * because there is no reader checking a limit that actually needs
          * to get both rlim_cur and rlim_max atomically, and either one
@@ -2183,27 +2200,14 @@ static inline int spin_needbreak(spinlock_t *lock)
 /*
  * Thread group CPU time accounting.
  */
-
-static inline
-void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
-{
-        struct task_cputime *totals = &tsk->signal->cputime.totals;
-        unsigned long flags;
-
-        spin_lock_irqsave(&totals->lock, flags);
-        *times = *totals;
-        spin_unlock_irqrestore(&totals->lock, flags);
-}
+void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
+void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
 
 static inline void thread_group_cputime_init(struct signal_struct *sig)
 {
-        sig->cputime.totals = (struct task_cputime){
-                .utime = cputime_zero,
-                .stime = cputime_zero,
-                .sum_exec_runtime = 0,
-        };
-
-        spin_lock_init(&sig->cputime.totals.lock);
+        sig->cputimer.cputime = INIT_CPUTIME;
+        spin_lock_init(&sig->cputimer.lock);
+        sig->cputimer.running = 0;
 }
 
 static inline void thread_group_cputime_free(struct signal_struct *sig)