Merge tag 'sound-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
[platform/adaptation/renesas_rcar/renesas_kernel.git] / kernel / sched / cputime.c
index 293b202..9857329 100644 (file)
@@ -3,6 +3,7 @@
 #include <linux/tsacct_kern.h>
 #include <linux/kernel_stat.h>
 #include <linux/static_key.h>
+#include <linux/context_tracking.h>
 #include "sched.h"
 
 
@@ -163,7 +164,7 @@ void account_user_time(struct task_struct *p, cputime_t cputime,
        task_group_account_field(p, index, (__force u64) cputime);
 
        /* Account for user time used */
-       acct_update_integrals(p);
+       acct_account_cputime(p);
 }
 
 /*
@@ -213,7 +214,7 @@ void __account_system_time(struct task_struct *p, cputime_t cputime,
        task_group_account_field(p, index, (__force u64) cputime);
 
        /* Account for system time used */
-       acct_update_integrals(p);
+       acct_account_cputime(p);
 }
 
 /*
@@ -295,6 +296,7 @@ static __always_inline bool steal_account_process_tick(void)
 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
 {
        struct signal_struct *sig = tsk->signal;
+       cputime_t utime, stime;
        struct task_struct *t;
 
        times->utime = sig->utime;
@@ -308,16 +310,15 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
 
        t = tsk;
        do {
-               times->utime += t->utime;
-               times->stime += t->stime;
+               task_cputime(tsk, &utime, &stime);
+               times->utime += utime;
+               times->stime += stime;
                times->sum_exec_runtime += task_sched_runtime(t);
        } while_each_thread(tsk, t);
 out:
        rcu_read_unlock();
 }
 
-#ifndef CONFIG_VIRT_CPU_ACCOUNTING
-
 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
 /*
  * Account a tick to a process and cpustat
@@ -382,11 +383,12 @@ static void irqtime_account_idle_ticks(int ticks)
                irqtime_account_process_tick(current, 0, rq);
 }
 #else /* CONFIG_IRQ_TIME_ACCOUNTING */
-static void irqtime_account_idle_ticks(int ticks) {}
-static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
+static inline void irqtime_account_idle_ticks(int ticks) {}
+static inline void irqtime_account_process_tick(struct task_struct *p, int user_tick,
                                                struct rq *rq) {}
 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
 
+#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 /*
  * Account a single tick of cpu time.
  * @p: the process that the cpu time gets accounted to
@@ -397,6 +399,9 @@ void account_process_tick(struct task_struct *p, int user_tick)
        cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
        struct rq *rq = this_rq();
 
+       if (vtime_accounting_enabled())
+               return;
+
        if (sched_clock_irqtime) {
                irqtime_account_process_tick(p, user_tick, rq);
                return;
@@ -438,8 +443,7 @@ void account_idle_ticks(unsigned long ticks)
 
        account_idle_time(jiffies_to_cputime(ticks));
 }
-
-#endif
+#endif /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
 
 /*
  * Use precise platform statistics if available:
@@ -461,25 +465,20 @@ void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime
        *st = cputime.stime;
 }
 
-void vtime_account_system_irqsafe(struct task_struct *tsk)
-{
-       unsigned long flags;
-
-       local_irq_save(flags);
-       vtime_account_system(tsk);
-       local_irq_restore(flags);
-}
-EXPORT_SYMBOL_GPL(vtime_account_system_irqsafe);
-
 #ifndef __ARCH_HAS_VTIME_TASK_SWITCH
 void vtime_task_switch(struct task_struct *prev)
 {
+       if (!vtime_accounting_enabled())
+               return;
+
        if (is_idle_task(prev))
                vtime_account_idle(prev);
        else
                vtime_account_system(prev);
 
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
        vtime_account_user(prev);
+#endif
        arch_vtime_task_switch(prev);
 }
 #endif
@@ -493,27 +492,40 @@ void vtime_task_switch(struct task_struct *prev)
  * vtime_account().
  */
 #ifndef __ARCH_HAS_VTIME_ACCOUNT
-void vtime_account(struct task_struct *tsk)
+void vtime_account_irq_enter(struct task_struct *tsk)
 {
-       if (in_interrupt() || !is_idle_task(tsk))
-               vtime_account_system(tsk);
-       else
-               vtime_account_idle(tsk);
+       if (!vtime_accounting_enabled())
+               return;
+
+       if (!in_interrupt()) {
+               /*
+                * If we interrupted user, context_tracking_in_user()
+                * is 1 because the context tracking don't hook
+                * on irq entry/exit. This way we know if
+                * we need to flush user time on kernel entry.
+                */
+               if (context_tracking_in_user()) {
+                       vtime_account_user(tsk);
+                       return;
+               }
+
+               if (is_idle_task(tsk)) {
+                       vtime_account_idle(tsk);
+                       return;
+               }
+       }
+       vtime_account_system(tsk);
 }
-EXPORT_SYMBOL_GPL(vtime_account);
+EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
 #endif /* __ARCH_HAS_VTIME_ACCOUNT */
 
-#else
-
-#ifndef nsecs_to_cputime
-# define nsecs_to_cputime(__nsecs)     nsecs_to_jiffies(__nsecs)
-#endif
+#else /* !CONFIG_VIRT_CPU_ACCOUNTING */
 
-static cputime_t scale_utime(cputime_t utime, cputime_t rtime, cputime_t total)
+static cputime_t scale_stime(cputime_t stime, cputime_t rtime, cputime_t total)
 {
        u64 temp = (__force u64) rtime;
 
-       temp *= (__force u64) utime;
+       temp *= (__force u64) stime;
 
        if (sizeof(cputime_t) == 4)
                temp = div_u64(temp, (__force u32) total);
@@ -531,10 +543,10 @@ static void cputime_adjust(struct task_cputime *curr,
                           struct cputime *prev,
                           cputime_t *ut, cputime_t *st)
 {
-       cputime_t rtime, utime, total;
+       cputime_t rtime, stime, total;
 
-       utime = curr->utime;
-       total = utime + curr->stime;
+       stime = curr->stime;
+       total = stime + curr->utime;
 
        /*
         * Tick based cputime accounting depend on random scheduling
@@ -549,17 +561,17 @@ static void cputime_adjust(struct task_cputime *curr,
        rtime = nsecs_to_cputime(curr->sum_exec_runtime);
 
        if (total)
-               utime = scale_utime(utime, rtime, total);
+               stime = scale_stime(stime, rtime, total);
        else
-               utime = rtime;
+               stime = rtime;
 
        /*
         * If the tick based count grows faster than the scheduler one,
         * the result of the scaling may go backward.
         * Let's enforce monotonicity.
         */
-       prev->utime = max(prev->utime, utime);
-       prev->stime = max(prev->stime, rtime - prev->utime);
+       prev->stime = max(prev->stime, stime);
+       prev->utime = max(prev->utime, rtime - prev->stime);
 
        *ut = prev->utime;
        *st = prev->stime;
@@ -568,11 +580,10 @@ static void cputime_adjust(struct task_cputime *curr,
 void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
 {
        struct task_cputime cputime = {
-               .utime = p->utime,
-               .stime = p->stime,
                .sum_exec_runtime = p->se.sum_exec_runtime,
        };
 
+       task_cputime(p, &cputime.utime, &cputime.stime);
        cputime_adjust(&cputime, &p->prev_cputime, ut, st);
 }
 
@@ -586,4 +597,221 @@ void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime
        thread_group_cputime(p, &cputime);
        cputime_adjust(&cputime, &p->signal->prev_cputime, ut, st);
 }
-#endif
+#endif /* !CONFIG_VIRT_CPU_ACCOUNTING */
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
+static unsigned long long vtime_delta(struct task_struct *tsk)
+{
+       unsigned long long clock;
+
+       clock = sched_clock();
+       if (clock < tsk->vtime_snap)
+               return 0;
+
+       return clock - tsk->vtime_snap;
+}
+
+static cputime_t get_vtime_delta(struct task_struct *tsk)
+{
+       unsigned long long delta = vtime_delta(tsk);
+
+       WARN_ON_ONCE(tsk->vtime_snap_whence == VTIME_SLEEPING);
+       tsk->vtime_snap += delta;
+
+       /* CHECKME: always safe to convert nsecs to cputime? */
+       return nsecs_to_cputime(delta);
+}
+
+static void __vtime_account_system(struct task_struct *tsk)
+{
+       cputime_t delta_cpu = get_vtime_delta(tsk);
+
+       account_system_time(tsk, irq_count(), delta_cpu, cputime_to_scaled(delta_cpu));
+}
+
+void vtime_account_system(struct task_struct *tsk)
+{
+       if (!vtime_accounting_enabled())
+               return;
+
+       write_seqlock(&tsk->vtime_seqlock);
+       __vtime_account_system(tsk);
+       write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_account_irq_exit(struct task_struct *tsk)
+{
+       if (!vtime_accounting_enabled())
+               return;
+
+       write_seqlock(&tsk->vtime_seqlock);
+       if (context_tracking_in_user())
+               tsk->vtime_snap_whence = VTIME_USER;
+       __vtime_account_system(tsk);
+       write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_account_user(struct task_struct *tsk)
+{
+       cputime_t delta_cpu;
+
+       if (!vtime_accounting_enabled())
+               return;
+
+       delta_cpu = get_vtime_delta(tsk);
+
+       write_seqlock(&tsk->vtime_seqlock);
+       tsk->vtime_snap_whence = VTIME_SYS;
+       account_user_time(tsk, delta_cpu, cputime_to_scaled(delta_cpu));
+       write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_user_enter(struct task_struct *tsk)
+{
+       if (!vtime_accounting_enabled())
+               return;
+
+       write_seqlock(&tsk->vtime_seqlock);
+       tsk->vtime_snap_whence = VTIME_USER;
+       __vtime_account_system(tsk);
+       write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_guest_enter(struct task_struct *tsk)
+{
+       write_seqlock(&tsk->vtime_seqlock);
+       __vtime_account_system(tsk);
+       current->flags |= PF_VCPU;
+       write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_guest_exit(struct task_struct *tsk)
+{
+       write_seqlock(&tsk->vtime_seqlock);
+       __vtime_account_system(tsk);
+       current->flags &= ~PF_VCPU;
+       write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_account_idle(struct task_struct *tsk)
+{
+       cputime_t delta_cpu = get_vtime_delta(tsk);
+
+       account_idle_time(delta_cpu);
+}
+
+bool vtime_accounting_enabled(void)
+{
+       return context_tracking_active();
+}
+
+void arch_vtime_task_switch(struct task_struct *prev)
+{
+       write_seqlock(&prev->vtime_seqlock);
+       prev->vtime_snap_whence = VTIME_SLEEPING;
+       write_sequnlock(&prev->vtime_seqlock);
+
+       write_seqlock(&current->vtime_seqlock);
+       current->vtime_snap_whence = VTIME_SYS;
+       current->vtime_snap = sched_clock();
+       write_sequnlock(&current->vtime_seqlock);
+}
+
+void vtime_init_idle(struct task_struct *t)
+{
+       unsigned long flags;
+
+       write_seqlock_irqsave(&t->vtime_seqlock, flags);
+       t->vtime_snap_whence = VTIME_SYS;
+       t->vtime_snap = sched_clock();
+       write_sequnlock_irqrestore(&t->vtime_seqlock, flags);
+}
+
+cputime_t task_gtime(struct task_struct *t)
+{
+       unsigned int seq;
+       cputime_t gtime;
+
+       do {
+               seq = read_seqbegin(&t->vtime_seqlock);
+
+               gtime = t->gtime;
+               if (t->flags & PF_VCPU)
+                       gtime += vtime_delta(t);
+
+       } while (read_seqretry(&t->vtime_seqlock, seq));
+
+       return gtime;
+}
+
+/*
+ * Fetch cputime raw values from fields of task_struct and
+ * add up the pending nohz execution time since the last
+ * cputime snapshot.
+ */
+static void
+fetch_task_cputime(struct task_struct *t,
+                  cputime_t *u_dst, cputime_t *s_dst,
+                  cputime_t *u_src, cputime_t *s_src,
+                  cputime_t *udelta, cputime_t *sdelta)
+{
+       unsigned int seq;
+       unsigned long long delta;
+
+       do {
+               *udelta = 0;
+               *sdelta = 0;
+
+               seq = read_seqbegin(&t->vtime_seqlock);
+
+               if (u_dst)
+                       *u_dst = *u_src;
+               if (s_dst)
+                       *s_dst = *s_src;
+
+               /* Task is sleeping, nothing to add */
+               if (t->vtime_snap_whence == VTIME_SLEEPING ||
+                   is_idle_task(t))
+                       continue;
+
+               delta = vtime_delta(t);
+
+               /*
+                * Task runs either in user or kernel space, add pending nohz time to
+                * the right place.
+                */
+               if (t->vtime_snap_whence == VTIME_USER || t->flags & PF_VCPU) {
+                       *udelta = delta;
+               } else {
+                       if (t->vtime_snap_whence == VTIME_SYS)
+                               *sdelta = delta;
+               }
+       } while (read_seqretry(&t->vtime_seqlock, seq));
+}
+
+
+void task_cputime(struct task_struct *t, cputime_t *utime, cputime_t *stime)
+{
+       cputime_t udelta, sdelta;
+
+       fetch_task_cputime(t, utime, stime, &t->utime,
+                          &t->stime, &udelta, &sdelta);
+       if (utime)
+               *utime += udelta;
+       if (stime)
+               *stime += sdelta;
+}
+
+void task_cputime_scaled(struct task_struct *t,
+                        cputime_t *utimescaled, cputime_t *stimescaled)
+{
+       cputime_t udelta, sdelta;
+
+       fetch_task_cputime(t, utimescaled, stimescaled,
+                          &t->utimescaled, &t->stimescaled, &udelta, &sdelta);
+       if (utimescaled)
+               *utimescaled += cputime_to_scaled(udelta);
+       if (stimescaled)
+               *stimescaled += cputime_to_scaled(sdelta);
+}
+#endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */