forked from ~ljy/RK356X_SDK_RELEASE
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hc
2023-12-09 b22da3d8526a935aa31e086e63f60ff3246cb61c 
 kernel/kernel/sched/cputime.c
....@@ -1,8 +1,10 @@
1
+// SPDX-License-Identifier: GPL-2.0-only
12 /*
23  * Simple CPU accounting cgroup controller
34  */
45 #include <linux/cpufreq_times.h>
56 #include "sched.h"
7
+#include <trace/hooks/sched.h>
68 
79 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
810 
....@@ -18,6 +20,7 @@
1820  * compromise in place of having locks on each irq in account_system_time.
1921  */
2022 DEFINE_PER_CPU(struct irqtime, cpu_irqtime);
23
+EXPORT_PER_CPU_SYMBOL_GPL(cpu_irqtime);
2124 
2225 static int sched_clock_irqtime;
2326 
....@@ -44,12 +47,13 @@
4447 }
4548 
4649 /*
47
- * Called before incrementing preempt_count on {soft,}irq_enter
50
+ * Called after incrementing preempt_count on {soft,}irq_enter
4851  * and before decrementing preempt_count on {soft,}irq_exit.
4952  */
50
-void irqtime_account_irq(struct task_struct *curr)
53
+void irqtime_account_irq(struct task_struct *curr, unsigned int offset)
5154 {
5255 	struct irqtime *irqtime = this_cpu_ptr(&cpu_irqtime);
56
+	unsigned int pc;
5357 	s64 delta;
5458 	int cpu;
5559 
....@@ -59,6 +63,7 @@
5963 	cpu = smp_processor_id();
6064 	delta = sched_clock_cpu(cpu) - irqtime->irq_start_time;
6165 	irqtime->irq_start_time += delta;
66
+	pc = irq_count() - offset;
6267 
6368 	/*
6469 	 * We do not account for softirq time from ksoftirqd here.
....@@ -66,10 +71,12 @@
6671 	 * in that case, so as not to confuse scheduler with a special task
6772 	 * that do not consume any time, but still wants to run.
6873 	 */
69
-	if (hardirq_count())
74
+	if (pc & HARDIRQ_MASK)
7075 		irqtime_account_delta(irqtime, delta, CPUTIME_IRQ);
71
-	else if (in_serving_softirq() && curr != this_cpu_ksoftirqd())
76
+	else if ((pc & SOFTIRQ_OFFSET) && curr != this_cpu_ksoftirqd())
7277 		irqtime_account_delta(irqtime, delta, CPUTIME_SOFTIRQ);
78
+
79
+	trace_android_rvh_account_irq(curr, cpu, delta);
7380 }
7481 EXPORT_SYMBOL_GPL(irqtime_account_irq);
7582 
....@@ -361,7 +368,7 @@
361368  * softirq as those do not count in task exec_runtime any more.
362369  */
363370 static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
364
-					 struct rq *rq, int ticks)
371
+					 int ticks)
365372 {
366373 	u64 other, cputime = TICK_NSEC * ticks;
367374 
....@@ -387,65 +394,59 @@
387394 		account_system_index_time(p, cputime, CPUTIME_SOFTIRQ);
388395 	} else if (user_tick) {
389396 		account_user_time(p, cputime);
390
-	} else if (p == rq->idle) {
397
+	} else if (p == this_rq()->idle) {
391398 		account_idle_time(cputime);
392399 	} else if (p->flags & PF_VCPU) { /* System time or guest time */
393400 		account_guest_time(p, cputime);
394401 	} else {
395402 		account_system_index_time(p, cputime, CPUTIME_SYSTEM);
396403 	}
404
+	trace_android_vh_irqtime_account_process_tick(p, this_rq(), user_tick, ticks);
397405 }
398406 
399407 static void irqtime_account_idle_ticks(int ticks)
400408 {
401
-	struct rq *rq = this_rq();
402
-
403
-	irqtime_account_process_tick(current, 0, rq, ticks);
409
+	irqtime_account_process_tick(current, 0, ticks);
404410 }
405411 #else /* CONFIG_IRQ_TIME_ACCOUNTING */
406412 static inline void irqtime_account_idle_ticks(int ticks) { }
407413 static inline void irqtime_account_process_tick(struct task_struct *p, int user_tick,
408
-						struct rq *rq, int nr_ticks) { }
414
+						int nr_ticks) { }
409415 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
410416 
411417 /*
412418  * Use precise platform statistics if available:
413419  */
414
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING
420
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
421
+
415422 # ifndef __ARCH_HAS_VTIME_TASK_SWITCH
416
-void vtime_common_task_switch(struct task_struct *prev)
423
+void vtime_task_switch(struct task_struct *prev)
417424 {
418425 	if (is_idle_task(prev))
419426 		vtime_account_idle(prev);
420427 	else
421
-		vtime_account_system(prev);
428
+		vtime_account_kernel(prev);
422429 
423430 	vtime_flush(prev);
424431 	arch_vtime_task_switch(prev);
425432 }
426433 # endif
427
-#endif /* CONFIG_VIRT_CPU_ACCOUNTING */
428434 
429
-
430
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
431
-/*
432
- * Archs that account the whole time spent in the idle task
433
- * (outside irq) as idle time can rely on this and just implement
434
- * vtime_account_system() and vtime_account_idle(). Archs that
435
- * have other meaning of the idle time (s390 only includes the
436
- * time spent by the CPU when it's in low power mode) must override
437
- * vtime_account().
438
- */
439
-#ifndef __ARCH_HAS_VTIME_ACCOUNT
440
-void vtime_account_irq_enter(struct task_struct *tsk)
435
+void vtime_account_irq(struct task_struct *tsk, unsigned int offset)
441436 {
442
-	if (!in_interrupt() && is_idle_task(tsk))
437
+	unsigned int pc = irq_count() - offset;
438
+
439
+	if (pc & HARDIRQ_OFFSET) {
440
+		vtime_account_hardirq(tsk);
441
+	} else if (pc & SOFTIRQ_OFFSET) {
442
+		vtime_account_softirq(tsk);
443
+	} else if (!IS_ENABLED(CONFIG_HAVE_VIRT_CPU_ACCOUNTING_IDLE) &&
444
+		   is_idle_task(tsk)) {
443445 		vtime_account_idle(tsk);
444
-	else
445
-		vtime_account_system(tsk);
446
+	} else {
447
+		vtime_account_kernel(tsk);
448
+	}
446449 }
447
-EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
448
-#endif /* __ARCH_HAS_VTIME_ACCOUNT */
449450 
450451 void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
451452 		    u64 *ut, u64 *st)
....@@ -470,6 +471,7 @@
470471 	*ut = cputime.utime;
471472 	*st = cputime.stime;
472473 }
474
+EXPORT_SYMBOL_GPL(thread_group_cputime_adjusted);
473475 
474476 #else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE: */
475477 
....@@ -481,13 +483,13 @@
481483 void account_process_tick(struct task_struct *p, int user_tick)
482484 {
483485 	u64 cputime, steal;
484
-	struct rq *rq = this_rq();
485486 
486
-	if (vtime_accounting_cpu_enabled())
487
+	if (vtime_accounting_enabled_this_cpu())
487488 		return;
489
+	trace_android_vh_account_task_time(p, this_rq(), user_tick);
488490 
489491 	if (sched_clock_irqtime) {
490
-		irqtime_account_process_tick(p, user_tick, rq, 1);
492
+		irqtime_account_process_tick(p, user_tick, 1);
491493 		return;
492494 	}
493495 
....@@ -501,7 +503,7 @@
501503 
502504 	if (user_tick)
503505 		account_user_time(p, cputime);
504
-	else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET))
506
+	else if ((p != this_rq()->idle) || (irq_count() != HARDIRQ_OFFSET))
505507 		account_system_time(p, HARDIRQ_OFFSET, cputime);
506508 	else
507509 		account_idle_time(cputime);
....@@ -528,50 +530,6 @@
528530 
529531 	cputime -= steal;
530532 	account_idle_time(cputime);
531
-}
532
-
533
-/*
534
- * Perform (stime * rtime) / total, but avoid multiplication overflow by
535
- * loosing precision when the numbers are big.
536
- */
537
-static u64 scale_stime(u64 stime, u64 rtime, u64 total)
538
-{
539
-	u64 scaled;
540
-
541
-	for (;;) {
542
-		/* Make sure "rtime" is the bigger of stime/rtime */
543
-		if (stime > rtime)
544
-			swap(rtime, stime);
545
-
546
-		/* Make sure 'total' fits in 32 bits */
547
-		if (total >> 32)
548
-			goto drop_precision;
549
-
550
-		/* Does rtime (and thus stime) fit in 32 bits? */
551
-		if (!(rtime >> 32))
552
-			break;
553
-
554
-		/* Can we just balance rtime/stime rather than dropping bits? */
555
-		if (stime >> 31)
556
-			goto drop_precision;
557
-
558
-		/* We can grow stime and shrink rtime and try to make them both fit */
559
-		stime <<= 1;
560
-		rtime >>= 1;
561
-		continue;
562
-
563
-drop_precision:
564
-		/* We drop from rtime, it has more bits than stime */
565
-		rtime >>= 1;
566
-		total >>= 1;
567
-	}
568
-
569
-	/*
570
-	 * Make sure gcc understands that this is a 32x32->64 multiply,
571
-	 * followed by a 64/32->64 divide.
572
-	 */
573
-	scaled = div_u64((u64) (u32) stime * (u64) (u32) rtime, (u32)total);
574
-	return scaled;
575533 }
576534 
577535 /*
....@@ -633,7 +591,7 @@
633591 		goto update;
634592 	}
635593 
636
-	stime = scale_stime(stime, rtime, stime + utime);
594
+	stime = mul_u64_u64_div_u64(stime, rtime, stime + utime);
637595 
638596 update:
639597 	/*
....@@ -684,6 +642,8 @@
684642 	thread_group_cputime(p, &cputime);
685643 	cputime_adjust(&cputime, &p->signal->prev_cputime, ut, st);
686644 }
645
+EXPORT_SYMBOL_GPL(thread_group_cputime_adjusted);
646
+
687647 #endif /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
688648 
689649 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
....@@ -717,8 +677,8 @@
717677 	return delta - other;
718678 }
719679 
720
-static void __vtime_account_system(struct task_struct *tsk,
721
-				   struct vtime *vtime)
680
+static void vtime_account_system(struct task_struct *tsk,
681
+				 struct vtime *vtime)
722682 {
723683 	vtime->stime += get_vtime_delta(vtime);
724684 	if (vtime->stime >= TICK_NSEC) {
....@@ -737,7 +697,17 @@
737697 	}
738698 }
739699 
740
-void vtime_account_system(struct task_struct *tsk)
700
+static void __vtime_account_kernel(struct task_struct *tsk,
701
+				   struct vtime *vtime)
702
+{
703
+	/* We might have scheduled out from guest path */
704
+	if (vtime->state == VTIME_GUEST)
705
+		vtime_account_guest(tsk, vtime);
706
+	else
707
+		vtime_account_system(tsk, vtime);
708
+}
709
+
710
+void vtime_account_kernel(struct task_struct *tsk)
741711 {
742712 	struct vtime *vtime = &tsk->vtime;
743713 
....@@ -745,11 +715,7 @@
745715 		return;
746716 
747717 	write_seqcount_begin(&vtime->seqcount);
748
-	/* We might have scheduled out from guest path */
749
-	if (tsk->flags & PF_VCPU)
750
-		vtime_account_guest(tsk, vtime);
751
-	else
752
-		__vtime_account_system(tsk, vtime);
718
+	__vtime_account_kernel(tsk, vtime);
753719 	write_seqcount_end(&vtime->seqcount);
754720 }
755721 
....@@ -758,7 +724,7 @@
758724 	struct vtime *vtime = &tsk->vtime;
759725 
760726 	write_seqcount_begin(&vtime->seqcount);
761
-	__vtime_account_system(tsk, vtime);
727
+	vtime_account_system(tsk, vtime);
762728 	vtime->state = VTIME_USER;
763729 	write_seqcount_end(&vtime->seqcount);
764730 }
....@@ -788,8 +754,9 @@
788754 	 * that can thus safely catch up with a tickless delta.
789755 	 */
790756 	write_seqcount_begin(&vtime->seqcount);
791
-	__vtime_account_system(tsk, vtime);
757
+	vtime_account_system(tsk, vtime);
792758 	tsk->flags |= PF_VCPU;
759
+	vtime->state = VTIME_GUEST;
793760 	write_seqcount_end(&vtime->seqcount);
794761 }
795762 EXPORT_SYMBOL_GPL(vtime_guest_enter);
....@@ -801,6 +768,7 @@
801768 	write_seqcount_begin(&vtime->seqcount);
802769 	vtime_account_guest(tsk, vtime);
803770 	tsk->flags &= ~PF_VCPU;
771
+	vtime->state = VTIME_SYS;
804772 	write_seqcount_end(&vtime->seqcount);
805773 }
806774 EXPORT_SYMBOL_GPL(vtime_guest_exit);
....@@ -810,19 +778,30 @@
810778 	account_idle_time(get_vtime_delta(&tsk->vtime));
811779 }
812780 
813
-void arch_vtime_task_switch(struct task_struct *prev)
781
+void vtime_task_switch_generic(struct task_struct *prev)
814782 {
815783 	struct vtime *vtime = &prev->vtime;
816784 
817785 	write_seqcount_begin(&vtime->seqcount);
786
+	if (vtime->state == VTIME_IDLE)
787
+		vtime_account_idle(prev);
788
+	else
789
+		__vtime_account_kernel(prev, vtime);
818790 	vtime->state = VTIME_INACTIVE;
791
+	vtime->cpu = -1;
819792 	write_seqcount_end(&vtime->seqcount);
820793 
821794 	vtime = &current->vtime;
822795 
823796 	write_seqcount_begin(&vtime->seqcount);
824
-	vtime->state = VTIME_SYS;
797
+	if (is_idle_task(current))
798
+		vtime->state = VTIME_IDLE;
799
+	else if (current->flags & PF_VCPU)
800
+		vtime->state = VTIME_GUEST;
801
+	else
802
+		vtime->state = VTIME_SYS;
825803 	vtime->starttime = sched_clock();
804
+	vtime->cpu = smp_processor_id();
826805 	write_seqcount_end(&vtime->seqcount);
827806 }
828807 
....@@ -833,8 +812,9 @@
833812 
834813 	local_irq_save(flags);
835814 	write_seqcount_begin(&vtime->seqcount);
836
-	vtime->state = VTIME_SYS;
815
+	vtime->state = VTIME_IDLE;
837816 	vtime->starttime = sched_clock();
817
+	vtime->cpu = cpu;
838818 	write_seqcount_end(&vtime->seqcount);
839819 	local_irq_restore(flags);
840820 }
....@@ -852,7 +832,7 @@
852832 		seq = read_seqcount_begin(&vtime->seqcount);
853833 
854834 		gtime = t->gtime;
855
-		if (vtime->state == VTIME_SYS && t->flags & PF_VCPU)
835
+		if (vtime->state == VTIME_GUEST)
856836 			gtime += vtime->gtime + vtime_delta(vtime);
857837 
858838 	} while (read_seqcount_retry(&vtime->seqcount, seq));
....@@ -883,20 +863,233 @@
883863 		*utime = t->utime;
884864 		*stime = t->stime;
885865 
886
-		/* Task is sleeping, nothing to add */
887
-		if (vtime->state == VTIME_INACTIVE || is_idle_task(t))
866
+		/* Task is sleeping or idle, nothing to add */
867
+		if (vtime->state < VTIME_SYS)
888868 			continue;
889869 
890870 		delta = vtime_delta(vtime);
891871 
892872 		/*
893
-		 * Task runs either in user or kernel space, add pending nohz time to
894
-		 * the right place.
873
+		 * Task runs either in user (including guest) or kernel space,
874
+		 * add pending nohz time to the right place.
895875 		 */
896
-		if (vtime->state == VTIME_USER || t->flags & PF_VCPU)
897
-			*utime += vtime->utime + delta;
898
-		else if (vtime->state == VTIME_SYS)
876
+		if (vtime->state == VTIME_SYS)
899877 			*stime += vtime->stime + delta;
878
+		else
879
+			*utime += vtime->utime + delta;
900880 	} while (read_seqcount_retry(&vtime->seqcount, seq));
901881 }
882
+
883
+static int vtime_state_fetch(struct vtime *vtime, int cpu)
884
+{
885
+	int state = READ_ONCE(vtime->state);
886
+
887
+	/*
888
+	 * We raced against a context switch, fetch the
889
+	 * kcpustat task again.
890
+	 */
891
+	if (vtime->cpu != cpu && vtime->cpu != -1)
892
+		return -EAGAIN;
893
+
894
+	/*
895
+	 * Two possible things here:
896
+	 * 1) We are seeing the scheduling out task (prev) or any past one.
897
+	 * 2) We are seeing the scheduling in task (next) but it hasn't
898
+	 *    passed though vtime_task_switch() yet so the pending
899
+	 *    cputime of the prev task may not be flushed yet.
900
+	 *
901
+	 * Case 1) is ok but 2) is not. So wait for a safe VTIME state.
902
+	 */
903
+	if (state == VTIME_INACTIVE)
904
+		return -EAGAIN;
905
+
906
+	return state;
907
+}
908
+
909
+static u64 kcpustat_user_vtime(struct vtime *vtime)
910
+{
911
+	if (vtime->state == VTIME_USER)
912
+		return vtime->utime + vtime_delta(vtime);
913
+	else if (vtime->state == VTIME_GUEST)
914
+		return vtime->gtime + vtime_delta(vtime);
915
+	return 0;
916
+}
917
+
918
+static int kcpustat_field_vtime(u64 *cpustat,
919
+				struct task_struct *tsk,
920
+				enum cpu_usage_stat usage,
921
+				int cpu, u64 *val)
922
+{
923
+	struct vtime *vtime = &tsk->vtime;
924
+	unsigned int seq;
925
+
926
+	do {
927
+		int state;
928
+
929
+		seq = read_seqcount_begin(&vtime->seqcount);
930
+
931
+		state = vtime_state_fetch(vtime, cpu);
932
+		if (state < 0)
933
+			return state;
934
+
935
+		*val = cpustat[usage];
936
+
937
+		/*
938
+		 * Nice VS unnice cputime accounting may be inaccurate if
939
+		 * the nice value has changed since the last vtime update.
940
+		 * But proper fix would involve interrupting target on nice
941
+		 * updates which is a no go on nohz_full (although the scheduler
942
+		 * may still interrupt the target if rescheduling is needed...)
943
+		 */
944
+		switch (usage) {
945
+		case CPUTIME_SYSTEM:
946
+			if (state == VTIME_SYS)
947
+				*val += vtime->stime + vtime_delta(vtime);
948
+			break;
949
+		case CPUTIME_USER:
950
+			if (task_nice(tsk) <= 0)
951
+				*val += kcpustat_user_vtime(vtime);
952
+			break;
953
+		case CPUTIME_NICE:
954
+			if (task_nice(tsk) > 0)
955
+				*val += kcpustat_user_vtime(vtime);
956
+			break;
957
+		case CPUTIME_GUEST:
958
+			if (state == VTIME_GUEST && task_nice(tsk) <= 0)
959
+				*val += vtime->gtime + vtime_delta(vtime);
960
+			break;
961
+		case CPUTIME_GUEST_NICE:
962
+			if (state == VTIME_GUEST && task_nice(tsk) > 0)
963
+				*val += vtime->gtime + vtime_delta(vtime);
964
+			break;
965
+		default:
966
+			break;
967
+		}
968
+	} while (read_seqcount_retry(&vtime->seqcount, seq));
969
+
970
+	return 0;
971
+}
972
+
973
+u64 kcpustat_field(struct kernel_cpustat *kcpustat,
974
+		   enum cpu_usage_stat usage, int cpu)
975
+{
976
+	u64 *cpustat = kcpustat->cpustat;
977
+	u64 val = cpustat[usage];
978
+	struct rq *rq;
979
+	int err;
980
+
981
+	if (!vtime_accounting_enabled_cpu(cpu))
982
+		return val;
983
+
984
+	rq = cpu_rq(cpu);
985
+
986
+	for (;;) {
987
+		struct task_struct *curr;
988
+
989
+		rcu_read_lock();
990
+		curr = rcu_dereference(rq->curr);
991
+		if (WARN_ON_ONCE(!curr)) {
992
+			rcu_read_unlock();
993
+			return cpustat[usage];
994
+		}
995
+
996
+		err = kcpustat_field_vtime(cpustat, curr, usage, cpu, &val);
997
+		rcu_read_unlock();
998
+
999
+		if (!err)
1000
+			return val;
1001
+
1002
+		cpu_relax();
1003
+	}
1004
+}
1005
+EXPORT_SYMBOL_GPL(kcpustat_field);
1006
+
1007
+static int kcpustat_cpu_fetch_vtime(struct kernel_cpustat *dst,
1008
+				    const struct kernel_cpustat *src,
1009
+				    struct task_struct *tsk, int cpu)
1010
+{
1011
+	struct vtime *vtime = &tsk->vtime;
1012
+	unsigned int seq;
1013
+
1014
+	do {
1015
+		u64 *cpustat;
1016
+		u64 delta;
1017
+		int state;
1018
+
1019
+		seq = read_seqcount_begin(&vtime->seqcount);
1020
+
1021
+		state = vtime_state_fetch(vtime, cpu);
1022
+		if (state < 0)
1023
+			return state;
1024
+
1025
+		*dst = *src;
1026
+		cpustat = dst->cpustat;
1027
+
1028
+		/* Task is sleeping, dead or idle, nothing to add */
1029
+		if (state < VTIME_SYS)
1030
+			continue;
1031
+
1032
+		delta = vtime_delta(vtime);
1033
+
1034
+		/*
1035
+		 * Task runs either in user (including guest) or kernel space,
1036
+		 * add pending nohz time to the right place.
1037
+		 */
1038
+		if (state == VTIME_SYS) {
1039
+			cpustat[CPUTIME_SYSTEM] += vtime->stime + delta;
1040
+		} else if (state == VTIME_USER) {
1041
+			if (task_nice(tsk) > 0)
1042
+				cpustat[CPUTIME_NICE] += vtime->utime + delta;
1043
+			else
1044
+				cpustat[CPUTIME_USER] += vtime->utime + delta;
1045
+		} else {
1046
+			WARN_ON_ONCE(state != VTIME_GUEST);
1047
+			if (task_nice(tsk) > 0) {
1048
+				cpustat[CPUTIME_GUEST_NICE] += vtime->gtime + delta;
1049
+				cpustat[CPUTIME_NICE] += vtime->gtime + delta;
1050
+			} else {
1051
+				cpustat[CPUTIME_GUEST] += vtime->gtime + delta;
1052
+				cpustat[CPUTIME_USER] += vtime->gtime + delta;
1053
+			}
1054
+		}
1055
+	} while (read_seqcount_retry(&vtime->seqcount, seq));
1056
+
1057
+	return 0;
1058
+}
1059
+
1060
+void kcpustat_cpu_fetch(struct kernel_cpustat *dst, int cpu)
1061
+{
1062
+	const struct kernel_cpustat *src = &kcpustat_cpu(cpu);
1063
+	struct rq *rq;
1064
+	int err;
1065
+
1066
+	if (!vtime_accounting_enabled_cpu(cpu)) {
1067
+		*dst = *src;
1068
+		return;
1069
+	}
1070
+
1071
+	rq = cpu_rq(cpu);
1072
+
1073
+	for (;;) {
1074
+		struct task_struct *curr;
1075
+
1076
+		rcu_read_lock();
1077
+		curr = rcu_dereference(rq->curr);
1078
+		if (WARN_ON_ONCE(!curr)) {
1079
+			rcu_read_unlock();
1080
+			*dst = *src;
1081
+			return;
1082
+		}
1083
+
1084
+		err = kcpustat_cpu_fetch_vtime(dst, src, curr, cpu);
1085
+		rcu_read_unlock();
1086
+
1087
+		if (!err)
1088
+			return;
1089
+
1090
+		cpu_relax();
1091
+	}
1092
+}
1093
+EXPORT_SYMBOL_GPL(kcpustat_cpu_fetch);
1094
+
9021095 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */