| .. | .. |
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| 1 | +// SPDX-License-Identifier: GPL-2.0-only |
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| 1 | 2 | /* |
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| 2 | 3 | * Simple CPU accounting cgroup controller |
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| 3 | 4 | */ |
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| 4 | 5 | #include <linux/cpufreq_times.h> |
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| 5 | 6 | #include "sched.h" |
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| 7 | +#include <trace/hooks/sched.h> |
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| 6 | 8 | |
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| 7 | 9 | #ifdef CONFIG_IRQ_TIME_ACCOUNTING |
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| 8 | 10 | |
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| .. | .. |
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| 18 | 20 | * compromise in place of having locks on each irq in account_system_time. |
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| 19 | 21 | */ |
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| 20 | 22 | DEFINE_PER_CPU(struct irqtime, cpu_irqtime); |
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| 23 | +EXPORT_PER_CPU_SYMBOL_GPL(cpu_irqtime); |
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| 21 | 24 | |
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| 22 | 25 | static int sched_clock_irqtime; |
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| 23 | 26 | |
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| .. | .. |
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| 70 | 73 | irqtime_account_delta(irqtime, delta, CPUTIME_IRQ); |
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| 71 | 74 | else if (in_serving_softirq() && curr != this_cpu_ksoftirqd()) |
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| 72 | 75 | irqtime_account_delta(irqtime, delta, CPUTIME_SOFTIRQ); |
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| 76 | + |
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| 77 | + trace_android_rvh_account_irq(curr, cpu, delta); |
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| 73 | 78 | } |
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| 74 | 79 | EXPORT_SYMBOL_GPL(irqtime_account_irq); |
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| 75 | 80 | |
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| .. | .. |
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| 361 | 366 | * softirq as those do not count in task exec_runtime any more. |
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| 362 | 367 | */ |
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| 363 | 368 | static void irqtime_account_process_tick(struct task_struct *p, int user_tick, |
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| 364 | | - struct rq *rq, int ticks) |
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| 369 | + int ticks) |
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| 365 | 370 | { |
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| 366 | 371 | u64 other, cputime = TICK_NSEC * ticks; |
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| 367 | 372 | |
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| .. | .. |
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| 387 | 392 | account_system_index_time(p, cputime, CPUTIME_SOFTIRQ); |
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| 388 | 393 | } else if (user_tick) { |
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| 389 | 394 | account_user_time(p, cputime); |
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| 390 | | - } else if (p == rq->idle) { |
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| 395 | + } else if (p == this_rq()->idle) { |
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| 391 | 396 | account_idle_time(cputime); |
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| 392 | 397 | } else if (p->flags & PF_VCPU) { /* System time or guest time */ |
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| 393 | 398 | account_guest_time(p, cputime); |
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| 394 | 399 | } else { |
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| 395 | 400 | account_system_index_time(p, cputime, CPUTIME_SYSTEM); |
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| 396 | 401 | } |
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| 402 | + trace_android_vh_irqtime_account_process_tick(p, this_rq(), user_tick, ticks); |
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| 397 | 403 | } |
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| 398 | 404 | |
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| 399 | 405 | static void irqtime_account_idle_ticks(int ticks) |
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| 400 | 406 | { |
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| 401 | | - struct rq *rq = this_rq(); |
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| 402 | | - |
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| 403 | | - irqtime_account_process_tick(current, 0, rq, ticks); |
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| 407 | + irqtime_account_process_tick(current, 0, ticks); |
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| 404 | 408 | } |
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| 405 | 409 | #else /* CONFIG_IRQ_TIME_ACCOUNTING */ |
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| 406 | 410 | static inline void irqtime_account_idle_ticks(int ticks) { } |
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| 407 | 411 | static inline void irqtime_account_process_tick(struct task_struct *p, int user_tick, |
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| 408 | | - struct rq *rq, int nr_ticks) { } |
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| 412 | + int nr_ticks) { } |
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| 409 | 413 | #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ |
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| 410 | 414 | |
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| 411 | 415 | /* |
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| 412 | 416 | * Use precise platform statistics if available: |
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| 413 | 417 | */ |
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| 414 | | -#ifdef CONFIG_VIRT_CPU_ACCOUNTING |
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| 418 | +#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE |
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| 419 | + |
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| 415 | 420 | # ifndef __ARCH_HAS_VTIME_TASK_SWITCH |
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| 416 | | -void vtime_common_task_switch(struct task_struct *prev) |
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| 421 | +void vtime_task_switch(struct task_struct *prev) |
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| 417 | 422 | { |
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| 418 | 423 | if (is_idle_task(prev)) |
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| 419 | 424 | vtime_account_idle(prev); |
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| 420 | 425 | else |
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| 421 | | - vtime_account_system(prev); |
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| 426 | + vtime_account_kernel(prev); |
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| 422 | 427 | |
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| 423 | 428 | vtime_flush(prev); |
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| 424 | 429 | arch_vtime_task_switch(prev); |
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| 425 | 430 | } |
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| 426 | 431 | # endif |
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| 427 | | -#endif /* CONFIG_VIRT_CPU_ACCOUNTING */ |
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| 428 | 432 | |
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| 429 | | - |
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| 430 | | -#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE |
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| 431 | 433 | /* |
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| 432 | 434 | * Archs that account the whole time spent in the idle task |
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| 433 | 435 | * (outside irq) as idle time can rely on this and just implement |
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| 434 | | - * vtime_account_system() and vtime_account_idle(). Archs that |
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| 436 | + * vtime_account_kernel() and vtime_account_idle(). Archs that |
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| 435 | 437 | * have other meaning of the idle time (s390 only includes the |
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| 436 | 438 | * time spent by the CPU when it's in low power mode) must override |
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| 437 | 439 | * vtime_account(). |
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| .. | .. |
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| 442 | 444 | if (!in_interrupt() && is_idle_task(tsk)) |
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| 443 | 445 | vtime_account_idle(tsk); |
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| 444 | 446 | else |
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| 445 | | - vtime_account_system(tsk); |
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| 447 | + vtime_account_kernel(tsk); |
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| 446 | 448 | } |
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| 447 | 449 | EXPORT_SYMBOL_GPL(vtime_account_irq_enter); |
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| 448 | 450 | #endif /* __ARCH_HAS_VTIME_ACCOUNT */ |
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| .. | .. |
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| 470 | 472 | *ut = cputime.utime; |
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| 471 | 473 | *st = cputime.stime; |
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| 472 | 474 | } |
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| 475 | +EXPORT_SYMBOL_GPL(thread_group_cputime_adjusted); |
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| 473 | 476 | |
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| 474 | 477 | #else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE: */ |
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| 475 | 478 | |
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| .. | .. |
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| 481 | 484 | void account_process_tick(struct task_struct *p, int user_tick) |
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| 482 | 485 | { |
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| 483 | 486 | u64 cputime, steal; |
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| 484 | | - struct rq *rq = this_rq(); |
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| 485 | 487 | |
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| 486 | | - if (vtime_accounting_cpu_enabled()) |
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| 488 | + if (vtime_accounting_enabled_this_cpu()) |
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| 487 | 489 | return; |
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| 490 | + trace_android_vh_account_task_time(p, this_rq(), user_tick); |
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| 488 | 491 | |
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| 489 | 492 | if (sched_clock_irqtime) { |
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| 490 | | - irqtime_account_process_tick(p, user_tick, rq, 1); |
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| 493 | + irqtime_account_process_tick(p, user_tick, 1); |
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| 491 | 494 | return; |
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| 492 | 495 | } |
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| 493 | 496 | |
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| .. | .. |
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| 501 | 504 | |
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| 502 | 505 | if (user_tick) |
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| 503 | 506 | account_user_time(p, cputime); |
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| 504 | | - else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET)) |
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| 507 | + else if ((p != this_rq()->idle) || (irq_count() != HARDIRQ_OFFSET)) |
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| 505 | 508 | account_system_time(p, HARDIRQ_OFFSET, cputime); |
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| 506 | 509 | else |
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| 507 | 510 | account_idle_time(cputime); |
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| .. | .. |
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| 528 | 531 | |
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| 529 | 532 | cputime -= steal; |
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| 530 | 533 | account_idle_time(cputime); |
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| 531 | | -} |
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| 532 | | - |
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| 533 | | -/* |
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| 534 | | - * Perform (stime * rtime) / total, but avoid multiplication overflow by |
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| 535 | | - * loosing precision when the numbers are big. |
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| 536 | | - */ |
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| 537 | | -static u64 scale_stime(u64 stime, u64 rtime, u64 total) |
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| 538 | | -{ |
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| 539 | | - u64 scaled; |
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| 540 | | - |
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| 541 | | - for (;;) { |
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| 542 | | - /* Make sure "rtime" is the bigger of stime/rtime */ |
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| 543 | | - if (stime > rtime) |
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| 544 | | - swap(rtime, stime); |
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| 545 | | - |
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| 546 | | - /* Make sure 'total' fits in 32 bits */ |
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| 547 | | - if (total >> 32) |
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| 548 | | - goto drop_precision; |
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| 549 | | - |
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| 550 | | - /* Does rtime (and thus stime) fit in 32 bits? */ |
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| 551 | | - if (!(rtime >> 32)) |
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| 552 | | - break; |
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| 553 | | - |
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| 554 | | - /* Can we just balance rtime/stime rather than dropping bits? */ |
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| 555 | | - if (stime >> 31) |
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| 556 | | - goto drop_precision; |
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| 557 | | - |
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| 558 | | - /* We can grow stime and shrink rtime and try to make them both fit */ |
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| 559 | | - stime <<= 1; |
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| 560 | | - rtime >>= 1; |
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| 561 | | - continue; |
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| 562 | | - |
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| 563 | | -drop_precision: |
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| 564 | | - /* We drop from rtime, it has more bits than stime */ |
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| 565 | | - rtime >>= 1; |
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| 566 | | - total >>= 1; |
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| 567 | | - } |
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| 568 | | - |
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| 569 | | - /* |
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| 570 | | - * Make sure gcc understands that this is a 32x32->64 multiply, |
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| 571 | | - * followed by a 64/32->64 divide. |
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| 572 | | - */ |
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| 573 | | - scaled = div_u64((u64) (u32) stime * (u64) (u32) rtime, (u32)total); |
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| 574 | | - return scaled; |
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| 575 | 534 | } |
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| 576 | 535 | |
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| 577 | 536 | /* |
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| .. | .. |
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| 633 | 592 | goto update; |
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| 634 | 593 | } |
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| 635 | 594 | |
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| 636 | | - stime = scale_stime(stime, rtime, stime + utime); |
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| 595 | + stime = mul_u64_u64_div_u64(stime, rtime, stime + utime); |
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| 637 | 596 | |
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| 638 | 597 | update: |
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| 639 | 598 | /* |
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| .. | .. |
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| 684 | 643 | thread_group_cputime(p, &cputime); |
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| 685 | 644 | cputime_adjust(&cputime, &p->signal->prev_cputime, ut, st); |
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| 686 | 645 | } |
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| 646 | +EXPORT_SYMBOL_GPL(thread_group_cputime_adjusted); |
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| 647 | + |
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| 687 | 648 | #endif /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ |
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| 688 | 649 | |
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| 689 | 650 | #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN |
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| .. | .. |
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| 717 | 678 | return delta - other; |
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| 718 | 679 | } |
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| 719 | 680 | |
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| 720 | | -static void __vtime_account_system(struct task_struct *tsk, |
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| 721 | | - struct vtime *vtime) |
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| 681 | +static void vtime_account_system(struct task_struct *tsk, |
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| 682 | + struct vtime *vtime) |
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| 722 | 683 | { |
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| 723 | 684 | vtime->stime += get_vtime_delta(vtime); |
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| 724 | 685 | if (vtime->stime >= TICK_NSEC) { |
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| .. | .. |
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| 737 | 698 | } |
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| 738 | 699 | } |
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| 739 | 700 | |
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| 740 | | -void vtime_account_system(struct task_struct *tsk) |
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| 701 | +static void __vtime_account_kernel(struct task_struct *tsk, |
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| 702 | + struct vtime *vtime) |
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| 703 | +{ |
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| 704 | + /* We might have scheduled out from guest path */ |
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| 705 | + if (vtime->state == VTIME_GUEST) |
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| 706 | + vtime_account_guest(tsk, vtime); |
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| 707 | + else |
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| 708 | + vtime_account_system(tsk, vtime); |
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| 709 | +} |
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| 710 | + |
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| 711 | +void vtime_account_kernel(struct task_struct *tsk) |
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| 741 | 712 | { |
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| 742 | 713 | struct vtime *vtime = &tsk->vtime; |
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| 743 | 714 | |
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| .. | .. |
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| 745 | 716 | return; |
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| 746 | 717 | |
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| 747 | 718 | write_seqcount_begin(&vtime->seqcount); |
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| 748 | | - /* We might have scheduled out from guest path */ |
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| 749 | | - if (tsk->flags & PF_VCPU) |
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| 750 | | - vtime_account_guest(tsk, vtime); |
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| 751 | | - else |
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| 752 | | - __vtime_account_system(tsk, vtime); |
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| 719 | + __vtime_account_kernel(tsk, vtime); |
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| 753 | 720 | write_seqcount_end(&vtime->seqcount); |
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| 754 | 721 | } |
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| 755 | 722 | |
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| .. | .. |
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| 758 | 725 | struct vtime *vtime = &tsk->vtime; |
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| 759 | 726 | |
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| 760 | 727 | write_seqcount_begin(&vtime->seqcount); |
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| 761 | | - __vtime_account_system(tsk, vtime); |
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| 728 | + vtime_account_system(tsk, vtime); |
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| 762 | 729 | vtime->state = VTIME_USER; |
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| 763 | 730 | write_seqcount_end(&vtime->seqcount); |
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| 764 | 731 | } |
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| .. | .. |
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| 788 | 755 | * that can thus safely catch up with a tickless delta. |
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| 789 | 756 | */ |
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| 790 | 757 | write_seqcount_begin(&vtime->seqcount); |
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| 791 | | - __vtime_account_system(tsk, vtime); |
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| 758 | + vtime_account_system(tsk, vtime); |
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| 792 | 759 | tsk->flags |= PF_VCPU; |
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| 760 | + vtime->state = VTIME_GUEST; |
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| 793 | 761 | write_seqcount_end(&vtime->seqcount); |
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| 794 | 762 | } |
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| 795 | 763 | EXPORT_SYMBOL_GPL(vtime_guest_enter); |
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| .. | .. |
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| 801 | 769 | write_seqcount_begin(&vtime->seqcount); |
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| 802 | 770 | vtime_account_guest(tsk, vtime); |
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| 803 | 771 | tsk->flags &= ~PF_VCPU; |
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| 772 | + vtime->state = VTIME_SYS; |
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| 804 | 773 | write_seqcount_end(&vtime->seqcount); |
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| 805 | 774 | } |
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| 806 | 775 | EXPORT_SYMBOL_GPL(vtime_guest_exit); |
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| .. | .. |
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| 810 | 779 | account_idle_time(get_vtime_delta(&tsk->vtime)); |
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| 811 | 780 | } |
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| 812 | 781 | |
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| 813 | | -void arch_vtime_task_switch(struct task_struct *prev) |
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| 782 | +void vtime_task_switch_generic(struct task_struct *prev) |
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| 814 | 783 | { |
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| 815 | 784 | struct vtime *vtime = &prev->vtime; |
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| 816 | 785 | |
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| 817 | 786 | write_seqcount_begin(&vtime->seqcount); |
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| 787 | + if (vtime->state == VTIME_IDLE) |
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| 788 | + vtime_account_idle(prev); |
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| 789 | + else |
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| 790 | + __vtime_account_kernel(prev, vtime); |
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| 818 | 791 | vtime->state = VTIME_INACTIVE; |
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| 792 | + vtime->cpu = -1; |
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| 819 | 793 | write_seqcount_end(&vtime->seqcount); |
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| 820 | 794 | |
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| 821 | 795 | vtime = ¤t->vtime; |
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| 822 | 796 | |
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| 823 | 797 | write_seqcount_begin(&vtime->seqcount); |
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| 824 | | - vtime->state = VTIME_SYS; |
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| 798 | + if (is_idle_task(current)) |
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| 799 | + vtime->state = VTIME_IDLE; |
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| 800 | + else if (current->flags & PF_VCPU) |
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| 801 | + vtime->state = VTIME_GUEST; |
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| 802 | + else |
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| 803 | + vtime->state = VTIME_SYS; |
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| 825 | 804 | vtime->starttime = sched_clock(); |
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| 805 | + vtime->cpu = smp_processor_id(); |
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| 826 | 806 | write_seqcount_end(&vtime->seqcount); |
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| 827 | 807 | } |
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| 828 | 808 | |
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| .. | .. |
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| 833 | 813 | |
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| 834 | 814 | local_irq_save(flags); |
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| 835 | 815 | write_seqcount_begin(&vtime->seqcount); |
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| 836 | | - vtime->state = VTIME_SYS; |
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| 816 | + vtime->state = VTIME_IDLE; |
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| 837 | 817 | vtime->starttime = sched_clock(); |
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| 818 | + vtime->cpu = cpu; |
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| 838 | 819 | write_seqcount_end(&vtime->seqcount); |
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| 839 | 820 | local_irq_restore(flags); |
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| 840 | 821 | } |
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| .. | .. |
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| 852 | 833 | seq = read_seqcount_begin(&vtime->seqcount); |
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| 853 | 834 | |
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| 854 | 835 | gtime = t->gtime; |
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| 855 | | - if (vtime->state == VTIME_SYS && t->flags & PF_VCPU) |
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| 836 | + if (vtime->state == VTIME_GUEST) |
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| 856 | 837 | gtime += vtime->gtime + vtime_delta(vtime); |
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| 857 | 838 | |
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| 858 | 839 | } while (read_seqcount_retry(&vtime->seqcount, seq)); |
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| .. | .. |
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| 883 | 864 | *utime = t->utime; |
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| 884 | 865 | *stime = t->stime; |
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| 885 | 866 | |
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| 886 | | - /* Task is sleeping, nothing to add */ |
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| 887 | | - if (vtime->state == VTIME_INACTIVE || is_idle_task(t)) |
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| 867 | + /* Task is sleeping or idle, nothing to add */ |
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| 868 | + if (vtime->state < VTIME_SYS) |
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| 888 | 869 | continue; |
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| 889 | 870 | |
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| 890 | 871 | delta = vtime_delta(vtime); |
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| 891 | 872 | |
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| 892 | 873 | /* |
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| 893 | | - * Task runs either in user or kernel space, add pending nohz time to |
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| 894 | | - * the right place. |
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| 874 | + * Task runs either in user (including guest) or kernel space, |
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| 875 | + * add pending nohz time to the right place. |
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| 895 | 876 | */ |
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| 896 | | - if (vtime->state == VTIME_USER || t->flags & PF_VCPU) |
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| 897 | | - *utime += vtime->utime + delta; |
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| 898 | | - else if (vtime->state == VTIME_SYS) |
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| 877 | + if (vtime->state == VTIME_SYS) |
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| 899 | 878 | *stime += vtime->stime + delta; |
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| 879 | + else |
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| 880 | + *utime += vtime->utime + delta; |
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| 900 | 881 | } while (read_seqcount_retry(&vtime->seqcount, seq)); |
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| 901 | 882 | } |
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| 883 | + |
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| 884 | +static int vtime_state_fetch(struct vtime *vtime, int cpu) |
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| 885 | +{ |
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| 886 | + int state = READ_ONCE(vtime->state); |
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| 887 | + |
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| 888 | + /* |
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| 889 | + * We raced against a context switch, fetch the |
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| 890 | + * kcpustat task again. |
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| 891 | + */ |
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| 892 | + if (vtime->cpu != cpu && vtime->cpu != -1) |
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| 893 | + return -EAGAIN; |
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| 894 | + |
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| 895 | + /* |
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| 896 | + * Two possible things here: |
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| 897 | + * 1) We are seeing the scheduling out task (prev) or any past one. |
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| 898 | + * 2) We are seeing the scheduling in task (next) but it hasn't |
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| 899 | + * passed though vtime_task_switch() yet so the pending |
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| 900 | + * cputime of the prev task may not be flushed yet. |
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| 901 | + * |
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| 902 | + * Case 1) is ok but 2) is not. So wait for a safe VTIME state. |
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| 903 | + */ |
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| 904 | + if (state == VTIME_INACTIVE) |
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| 905 | + return -EAGAIN; |
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| 906 | + |
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| 907 | + return state; |
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| 908 | +} |
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| 909 | + |
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| 910 | +static u64 kcpustat_user_vtime(struct vtime *vtime) |
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| 911 | +{ |
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| 912 | + if (vtime->state == VTIME_USER) |
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| 913 | + return vtime->utime + vtime_delta(vtime); |
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| 914 | + else if (vtime->state == VTIME_GUEST) |
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| 915 | + return vtime->gtime + vtime_delta(vtime); |
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| 916 | + return 0; |
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| 917 | +} |
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| 918 | + |
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| 919 | +static int kcpustat_field_vtime(u64 *cpustat, |
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| 920 | + struct task_struct *tsk, |
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| 921 | + enum cpu_usage_stat usage, |
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| 922 | + int cpu, u64 *val) |
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| 923 | +{ |
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| 924 | + struct vtime *vtime = &tsk->vtime; |
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| 925 | + unsigned int seq; |
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| 926 | + |
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| 927 | + do { |
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| 928 | + int state; |
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| 929 | + |
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| 930 | + seq = read_seqcount_begin(&vtime->seqcount); |
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| 931 | + |
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| 932 | + state = vtime_state_fetch(vtime, cpu); |
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| 933 | + if (state < 0) |
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| 934 | + return state; |
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| 935 | + |
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| 936 | + *val = cpustat[usage]; |
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| 937 | + |
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| 938 | + /* |
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| 939 | + * Nice VS unnice cputime accounting may be inaccurate if |
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| 940 | + * the nice value has changed since the last vtime update. |
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| 941 | + * But proper fix would involve interrupting target on nice |
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| 942 | + * updates which is a no go on nohz_full (although the scheduler |
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| 943 | + * may still interrupt the target if rescheduling is needed...) |
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| 944 | + */ |
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| 945 | + switch (usage) { |
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| 946 | + case CPUTIME_SYSTEM: |
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| 947 | + if (state == VTIME_SYS) |
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| 948 | + *val += vtime->stime + vtime_delta(vtime); |
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| 949 | + break; |
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| 950 | + case CPUTIME_USER: |
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| 951 | + if (task_nice(tsk) <= 0) |
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| 952 | + *val += kcpustat_user_vtime(vtime); |
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| 953 | + break; |
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| 954 | + case CPUTIME_NICE: |
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| 955 | + if (task_nice(tsk) > 0) |
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| 956 | + *val += kcpustat_user_vtime(vtime); |
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| 957 | + break; |
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| 958 | + case CPUTIME_GUEST: |
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| 959 | + if (state == VTIME_GUEST && task_nice(tsk) <= 0) |
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| 960 | + *val += vtime->gtime + vtime_delta(vtime); |
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| 961 | + break; |
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| 962 | + case CPUTIME_GUEST_NICE: |
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| 963 | + if (state == VTIME_GUEST && task_nice(tsk) > 0) |
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| 964 | + *val += vtime->gtime + vtime_delta(vtime); |
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| 965 | + break; |
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| 966 | + default: |
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| 967 | + break; |
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| 968 | + } |
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| 969 | + } while (read_seqcount_retry(&vtime->seqcount, seq)); |
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| 970 | + |
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| 971 | + return 0; |
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| 972 | +} |
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| 973 | + |
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| 974 | +u64 kcpustat_field(struct kernel_cpustat *kcpustat, |
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| 975 | + enum cpu_usage_stat usage, int cpu) |
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| 976 | +{ |
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| 977 | + u64 *cpustat = kcpustat->cpustat; |
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| 978 | + u64 val = cpustat[usage]; |
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| 979 | + struct rq *rq; |
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| 980 | + int err; |
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| 981 | + |
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| 982 | + if (!vtime_accounting_enabled_cpu(cpu)) |
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| 983 | + return val; |
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| 984 | + |
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| 985 | + rq = cpu_rq(cpu); |
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| 986 | + |
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| 987 | + for (;;) { |
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| 988 | + struct task_struct *curr; |
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| 989 | + |
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| 990 | + rcu_read_lock(); |
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| 991 | + curr = rcu_dereference(rq->curr); |
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| 992 | + if (WARN_ON_ONCE(!curr)) { |
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| 993 | + rcu_read_unlock(); |
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| 994 | + return cpustat[usage]; |
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| 995 | + } |
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| 996 | + |
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| 997 | + err = kcpustat_field_vtime(cpustat, curr, usage, cpu, &val); |
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| 998 | + rcu_read_unlock(); |
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| 999 | + |
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| 1000 | + if (!err) |
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| 1001 | + return val; |
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| 1002 | + |
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| 1003 | + cpu_relax(); |
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| 1004 | + } |
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| 1005 | +} |
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| 1006 | +EXPORT_SYMBOL_GPL(kcpustat_field); |
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| 1007 | + |
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| 1008 | +static int kcpustat_cpu_fetch_vtime(struct kernel_cpustat *dst, |
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| 1009 | + const struct kernel_cpustat *src, |
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| 1010 | + struct task_struct *tsk, int cpu) |
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| 1011 | +{ |
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| 1012 | + struct vtime *vtime = &tsk->vtime; |
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| 1013 | + unsigned int seq; |
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| 1014 | + |
|---|
| 1015 | + do { |
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| 1016 | + u64 *cpustat; |
|---|
| 1017 | + u64 delta; |
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| 1018 | + int state; |
|---|
| 1019 | + |
|---|
| 1020 | + seq = read_seqcount_begin(&vtime->seqcount); |
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| 1021 | + |
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| 1022 | + state = vtime_state_fetch(vtime, cpu); |
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| 1023 | + if (state < 0) |
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| 1024 | + return state; |
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| 1025 | + |
|---|
| 1026 | + *dst = *src; |
|---|
| 1027 | + cpustat = dst->cpustat; |
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| 1028 | + |
|---|
| 1029 | + /* Task is sleeping, dead or idle, nothing to add */ |
|---|
| 1030 | + if (state < VTIME_SYS) |
|---|
| 1031 | + continue; |
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| 1032 | + |
|---|
| 1033 | + delta = vtime_delta(vtime); |
|---|
| 1034 | + |
|---|
| 1035 | + /* |
|---|
| 1036 | + * Task runs either in user (including guest) or kernel space, |
|---|
| 1037 | + * add pending nohz time to the right place. |
|---|
| 1038 | + */ |
|---|
| 1039 | + if (state == VTIME_SYS) { |
|---|
| 1040 | + cpustat[CPUTIME_SYSTEM] += vtime->stime + delta; |
|---|
| 1041 | + } else if (state == VTIME_USER) { |
|---|
| 1042 | + if (task_nice(tsk) > 0) |
|---|
| 1043 | + cpustat[CPUTIME_NICE] += vtime->utime + delta; |
|---|
| 1044 | + else |
|---|
| 1045 | + cpustat[CPUTIME_USER] += vtime->utime + delta; |
|---|
| 1046 | + } else { |
|---|
| 1047 | + WARN_ON_ONCE(state != VTIME_GUEST); |
|---|
| 1048 | + if (task_nice(tsk) > 0) { |
|---|
| 1049 | + cpustat[CPUTIME_GUEST_NICE] += vtime->gtime + delta; |
|---|
| 1050 | + cpustat[CPUTIME_NICE] += vtime->gtime + delta; |
|---|
| 1051 | + } else { |
|---|
| 1052 | + cpustat[CPUTIME_GUEST] += vtime->gtime + delta; |
|---|
| 1053 | + cpustat[CPUTIME_USER] += vtime->gtime + delta; |
|---|
| 1054 | + } |
|---|
| 1055 | + } |
|---|
| 1056 | + } while (read_seqcount_retry(&vtime->seqcount, seq)); |
|---|
| 1057 | + |
|---|
| 1058 | + return 0; |
|---|
| 1059 | +} |
|---|
| 1060 | + |
|---|
| 1061 | +void kcpustat_cpu_fetch(struct kernel_cpustat *dst, int cpu) |
|---|
| 1062 | +{ |
|---|
| 1063 | + const struct kernel_cpustat *src = &kcpustat_cpu(cpu); |
|---|
| 1064 | + struct rq *rq; |
|---|
| 1065 | + int err; |
|---|
| 1066 | + |
|---|
| 1067 | + if (!vtime_accounting_enabled_cpu(cpu)) { |
|---|
| 1068 | + *dst = *src; |
|---|
| 1069 | + return; |
|---|
| 1070 | + } |
|---|
| 1071 | + |
|---|
| 1072 | + rq = cpu_rq(cpu); |
|---|
| 1073 | + |
|---|
| 1074 | + for (;;) { |
|---|
| 1075 | + struct task_struct *curr; |
|---|
| 1076 | + |
|---|
| 1077 | + rcu_read_lock(); |
|---|
| 1078 | + curr = rcu_dereference(rq->curr); |
|---|
| 1079 | + if (WARN_ON_ONCE(!curr)) { |
|---|
| 1080 | + rcu_read_unlock(); |
|---|
| 1081 | + *dst = *src; |
|---|
| 1082 | + return; |
|---|
| 1083 | + } |
|---|
| 1084 | + |
|---|
| 1085 | + err = kcpustat_cpu_fetch_vtime(dst, src, curr, cpu); |
|---|
| 1086 | + rcu_read_unlock(); |
|---|
| 1087 | + |
|---|
| 1088 | + if (!err) |
|---|
| 1089 | + return; |
|---|
| 1090 | + |
|---|
| 1091 | + cpu_relax(); |
|---|
| 1092 | + } |
|---|
| 1093 | +} |
|---|
| 1094 | +EXPORT_SYMBOL_GPL(kcpustat_cpu_fetch); |
|---|
| 1095 | + |
|---|
| 902 | 1096 | #endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */ |
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