From 8a6a5920d3286eb0eae9f36a4ec4fc9df511eccb Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Wed, 2 Dec 2020 12:57:30 +0100 Subject: [PATCH] sched/vtime: Consolidate IRQ time accounting The 3 architectures implementing CONFIG_VIRT_CPU_ACCOUNTING_NATIVE all have their own version of irq time accounting that dispatch the cputime to the appropriate index: hardirq, softirq, system, idle, guest... from an all-in-one function. Instead of having these ad-hoc versions, move the cputime destination dispatch decision to the core code and leave only the actual per-index cputime accounting to the architecture. Signed-off-by: Frederic Weisbecker Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20201202115732.27827-4-frederic@kernel.org --- arch/ia64/kernel/time.c | 20 ++++++++++---- arch/powerpc/kernel/time.c | 56 +++++++++++++++++++++++++++----------- arch/s390/kernel/vtime.c | 45 +++++++++++++++++++++--------- include/linux/vtime.h | 16 ++++------- kernel/sched/cputime.c | 13 ++++++--- 5 files changed, 102 insertions(+), 48 deletions(-) diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c index 7abc5f37bfaf..733e0e3324b8 100644 --- a/arch/ia64/kernel/time.c +++ b/arch/ia64/kernel/time.c @@ -138,12 +138,8 @@ void vtime_account_kernel(struct task_struct *tsk) struct thread_info *ti = task_thread_info(tsk); __u64 stime = vtime_delta(tsk); - if ((tsk->flags & PF_VCPU) && !irq_count()) + if (tsk->flags & PF_VCPU) ti->gtime += stime; - else if (hardirq_count()) - ti->hardirq_time += stime; - else if (in_serving_softirq()) - ti->softirq_time += stime; else ti->stime += stime; } @@ -156,6 +152,20 @@ void vtime_account_idle(struct task_struct *tsk) ti->idle_time += vtime_delta(tsk); } +void vtime_account_softirq(struct task_struct *tsk) +{ + struct thread_info *ti = task_thread_info(tsk); + + ti->softirq_time += vtime_delta(tsk); +} + +void vtime_account_hardirq(struct task_struct *tsk) +{ + struct thread_info *ti = task_thread_info(tsk); + + ti->hardirq_time += vtime_delta(tsk); +} + #endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ static irqreturn_t diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 74efe46f5532..cf3f8db7e0e3 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -311,12 +311,11 @@ static unsigned long vtime_delta_scaled(struct cpu_accounting_data *acct, return stime_scaled; } -static unsigned long vtime_delta(struct task_struct *tsk, +static unsigned long vtime_delta(struct cpu_accounting_data *acct, unsigned long *stime_scaled, unsigned long *steal_time) { unsigned long now, stime; - struct cpu_accounting_data *acct = get_accounting(tsk); WARN_ON_ONCE(!irqs_disabled()); @@ -331,29 +330,30 @@ static unsigned long vtime_delta(struct task_struct *tsk, return stime; } +static void vtime_delta_kernel(struct cpu_accounting_data *acct, + unsigned long *stime, unsigned long *stime_scaled) +{ + unsigned long steal_time; + + *stime = vtime_delta(acct, stime_scaled, &steal_time); + *stime -= min(*stime, steal_time); + acct->steal_time += steal_time; +} + void vtime_account_kernel(struct task_struct *tsk) { - unsigned long stime, stime_scaled, steal_time; struct cpu_accounting_data *acct = get_accounting(tsk); + unsigned long stime, stime_scaled; - stime = vtime_delta(tsk, &stime_scaled, &steal_time); + vtime_delta_kernel(acct, &stime, &stime_scaled); - stime -= min(stime, steal_time); - acct->steal_time += steal_time; - - if ((tsk->flags & PF_VCPU) && !irq_count()) { + if (tsk->flags & PF_VCPU) { acct->gtime += stime; #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME acct->utime_scaled += stime_scaled; #endif } else { - if (hardirq_count()) - acct->hardirq_time += stime; - else if (in_serving_softirq()) - acct->softirq_time += stime; - else - acct->stime += stime; - + acct->stime += stime; #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME acct->stime_scaled += stime_scaled; #endif @@ -366,10 +366,34 @@ void vtime_account_idle(struct task_struct *tsk) unsigned long stime, stime_scaled, steal_time; struct cpu_accounting_data *acct = get_accounting(tsk); - stime = vtime_delta(tsk, &stime_scaled, &steal_time); + stime = vtime_delta(acct, &stime_scaled, &steal_time); acct->idle_time += stime + steal_time; } +static void vtime_account_irq_field(struct cpu_accounting_data *acct, + unsigned long *field) +{ + unsigned long stime, stime_scaled; + + vtime_delta_kernel(acct, &stime, &stime_scaled); + *field += stime; +#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME + acct->stime_scaled += stime_scaled; +#endif +} + +void vtime_account_softirq(struct task_struct *tsk) +{ + struct cpu_accounting_data *acct = get_accounting(tsk); + vtime_account_irq_field(acct, &acct->softirq_time); +} + +void vtime_account_hardirq(struct task_struct *tsk) +{ + struct cpu_accounting_data *acct = get_accounting(tsk); + vtime_account_irq_field(acct, &acct->hardirq_time); +} + static void vtime_flush_scaled(struct task_struct *tsk, struct cpu_accounting_data *acct) { diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c index ebd8e5655789..5aaa2ca6a928 100644 --- a/arch/s390/kernel/vtime.c +++ b/arch/s390/kernel/vtime.c @@ -222,31 +222,50 @@ void vtime_flush(struct task_struct *tsk) S390_lowcore.avg_steal_timer = avg_steal; } +static u64 vtime_delta(void) +{ + u64 timer = S390_lowcore.last_update_timer; + + S390_lowcore.last_update_timer = get_vtimer(); + + return timer - S390_lowcore.last_update_timer; +} + /* * Update process times based on virtual cpu times stored by entry.S * to the lowcore fields user_timer, system_timer & steal_clock. */ void vtime_account_kernel(struct task_struct *tsk) { - u64 timer; + u64 delta = vtime_delta(); - timer = S390_lowcore.last_update_timer; - S390_lowcore.last_update_timer = get_vtimer(); - timer -= S390_lowcore.last_update_timer; - - if ((tsk->flags & PF_VCPU) && (irq_count() == 0)) - S390_lowcore.guest_timer += timer; - else if (hardirq_count()) - S390_lowcore.hardirq_timer += timer; - else if (in_serving_softirq()) - S390_lowcore.softirq_timer += timer; + if (tsk->flags & PF_VCPU) + S390_lowcore.guest_timer += delta; else - S390_lowcore.system_timer += timer; + S390_lowcore.system_timer += delta; - virt_timer_forward(timer); + virt_timer_forward(delta); } EXPORT_SYMBOL_GPL(vtime_account_kernel); +void vtime_account_softirq(struct task_struct *tsk) +{ + u64 delta = vtime_delta(); + + S390_lowcore.softirq_timer += delta; + + virt_timer_forward(delta); +} + +void vtime_account_hardirq(struct task_struct *tsk) +{ + u64 delta = vtime_delta(); + + S390_lowcore.hardirq_timer += delta; + + virt_timer_forward(delta); +} + /* * Sorted add to a list. List is linear searched until first bigger * element is found. diff --git a/include/linux/vtime.h b/include/linux/vtime.h index 2cdeca062db3..6c9867419615 100644 --- a/include/linux/vtime.h +++ b/include/linux/vtime.h @@ -83,16 +83,12 @@ static inline void vtime_init_idle(struct task_struct *tsk, int cpu) { } #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE -extern void vtime_account_irq_enter(struct task_struct *tsk); -static inline void vtime_account_irq_exit(struct task_struct *tsk) -{ - /* On hard|softirq exit we always account to hard|softirq cputime */ - vtime_account_kernel(tsk); -} +extern void vtime_account_irq(struct task_struct *tsk); +extern void vtime_account_softirq(struct task_struct *tsk); +extern void vtime_account_hardirq(struct task_struct *tsk); extern void vtime_flush(struct task_struct *tsk); #else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ -static inline void vtime_account_irq_enter(struct task_struct *tsk) { } -static inline void vtime_account_irq_exit(struct task_struct *tsk) { } +static inline void vtime_account_irq(struct task_struct *tsk) { } static inline void vtime_flush(struct task_struct *tsk) { } #endif @@ -105,13 +101,13 @@ static inline void irqtime_account_irq(struct task_struct *tsk) { } static inline void account_irq_enter_time(struct task_struct *tsk) { - vtime_account_irq_enter(tsk); + vtime_account_irq(tsk); irqtime_account_irq(tsk); } static inline void account_irq_exit_time(struct task_struct *tsk) { - vtime_account_irq_exit(tsk); + vtime_account_irq(tsk); irqtime_account_irq(tsk); } diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index 2783162542b1..02163d4260d7 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -417,13 +417,18 @@ void vtime_task_switch(struct task_struct *prev) } # endif -void vtime_account_irq_enter(struct task_struct *tsk) +void vtime_account_irq(struct task_struct *tsk) { - if (!IS_ENABLED(CONFIG_HAVE_VIRT_CPU_ACCOUNTING_IDLE) && - !in_interrupt() && is_idle_task(tsk)) + if (hardirq_count()) { + vtime_account_hardirq(tsk); + } else if (in_serving_softirq()) { + vtime_account_softirq(tsk); + } else if (!IS_ENABLED(CONFIG_HAVE_VIRT_CPU_ACCOUNTING_IDLE) && + is_idle_task(tsk)) { vtime_account_idle(tsk); - else + } else { vtime_account_kernel(tsk); + } } void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,