diff options
-rw-r--r-- | arch/x86/include/asm/context_tracking.h | 21 | ||||
-rw-r--r-- | arch/x86/kernel/kvm.c | 8 | ||||
-rw-r--r-- | arch/x86/kernel/traps.c | 68 | ||||
-rw-r--r-- | arch/x86/mm/fault.c | 8 | ||||
-rw-r--r-- | include/linux/context_tracking.h | 24 | ||||
-rw-r--r-- | include/linux/sched.h | 4 | ||||
-rw-r--r-- | init/Kconfig | 1 | ||||
-rw-r--r-- | kernel/fork.c | 2 | ||||
-rw-r--r-- | kernel/sched/core.c | 6 | ||||
-rw-r--r-- | kernel/sched/cputime.c | 154 |
10 files changed, 163 insertions, 133 deletions
diff --git a/arch/x86/include/asm/context_tracking.h b/arch/x86/include/asm/context_tracking.h index 1616562..1fe4970 100644 --- a/arch/x86/include/asm/context_tracking.h +++ b/arch/x86/include/asm/context_tracking.h @@ -1,31 +1,10 @@ #ifndef _ASM_X86_CONTEXT_TRACKING_H #define _ASM_X86_CONTEXT_TRACKING_H -#ifndef __ASSEMBLY__ -#include <linux/context_tracking.h> -#include <asm/ptrace.h> - -static inline void exception_enter(struct pt_regs *regs) -{ - user_exit(); -} - -static inline void exception_exit(struct pt_regs *regs) -{ -#ifdef CONFIG_CONTEXT_TRACKING - if (user_mode(regs)) - user_enter(); -#endif -} - -#else /* __ASSEMBLY__ */ - #ifdef CONFIG_CONTEXT_TRACKING # define SCHEDULE_USER call schedule_user #else # define SCHEDULE_USER call schedule #endif -#endif /* !__ASSEMBLY__ */ - #endif diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index b686a90..cd6d9a5 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -20,6 +20,7 @@ * Authors: Anthony Liguori <aliguori@us.ibm.com> */ +#include <linux/context_tracking.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/kvm_para.h> @@ -43,7 +44,6 @@ #include <asm/apicdef.h> #include <asm/hypervisor.h> #include <asm/kvm_guest.h> -#include <asm/context_tracking.h> static int kvmapf = 1; @@ -254,16 +254,18 @@ EXPORT_SYMBOL_GPL(kvm_read_and_reset_pf_reason); dotraplinkage void __kprobes do_async_page_fault(struct pt_regs *regs, unsigned long error_code) { + enum ctx_state prev_state; + switch (kvm_read_and_reset_pf_reason()) { default: do_page_fault(regs, error_code); break; case KVM_PV_REASON_PAGE_NOT_PRESENT: /* page is swapped out by the host. */ - exception_enter(regs); + prev_state = exception_enter(); exit_idle(); kvm_async_pf_task_wait((u32)read_cr2()); - exception_exit(regs); + exception_exit(prev_state); break; case KVM_PV_REASON_PAGE_READY: rcu_irq_enter(); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 68bda7a..ff6d227 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -12,6 +12,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/context_tracking.h> #include <linux/interrupt.h> #include <linux/kallsyms.h> #include <linux/spinlock.h> @@ -55,8 +56,6 @@ #include <asm/i387.h> #include <asm/fpu-internal.h> #include <asm/mce.h> -#include <asm/context_tracking.h> - #include <asm/mach_traps.h> #ifdef CONFIG_X86_64 @@ -176,34 +175,38 @@ do_trap(int trapnr, int signr, char *str, struct pt_regs *regs, #define DO_ERROR(trapnr, signr, str, name) \ dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \ { \ - exception_enter(regs); \ + enum ctx_state prev_state; \ + \ + prev_state = exception_enter(); \ if (notify_die(DIE_TRAP, str, regs, error_code, \ trapnr, signr) == NOTIFY_STOP) { \ - exception_exit(regs); \ + exception_exit(prev_state); \ return; \ } \ conditional_sti(regs); \ do_trap(trapnr, signr, str, regs, error_code, NULL); \ - exception_exit(regs); \ + exception_exit(prev_state); \ } #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \ { \ siginfo_t info; \ + enum ctx_state prev_state; \ + \ info.si_signo = signr; \ info.si_errno = 0; \ info.si_code = sicode; \ info.si_addr = (void __user *)siaddr; \ - exception_enter(regs); \ + prev_state = exception_enter(); \ if (notify_die(DIE_TRAP, str, regs, error_code, \ trapnr, signr) == NOTIFY_STOP) { \ - exception_exit(regs); \ + exception_exit(prev_state); \ return; \ } \ conditional_sti(regs); \ do_trap(trapnr, signr, str, regs, error_code, &info); \ - exception_exit(regs); \ + exception_exit(prev_state); \ } DO_ERROR_INFO(X86_TRAP_DE, SIGFPE, "divide error", divide_error, FPE_INTDIV, @@ -226,14 +229,16 @@ DO_ERROR_INFO(X86_TRAP_AC, SIGBUS, "alignment check", alignment_check, /* Runs on IST stack */ dotraplinkage void do_stack_segment(struct pt_regs *regs, long error_code) { - exception_enter(regs); + enum ctx_state prev_state; + + prev_state = exception_enter(); if (notify_die(DIE_TRAP, "stack segment", regs, error_code, X86_TRAP_SS, SIGBUS) != NOTIFY_STOP) { preempt_conditional_sti(regs); do_trap(X86_TRAP_SS, SIGBUS, "stack segment", regs, error_code, NULL); preempt_conditional_cli(regs); } - exception_exit(regs); + exception_exit(prev_state); } dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) @@ -241,7 +246,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) static const char str[] = "double fault"; struct task_struct *tsk = current; - exception_enter(regs); + exception_enter(); /* Return not checked because double check cannot be ignored */ notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV); @@ -261,8 +266,9 @@ dotraplinkage void __kprobes do_general_protection(struct pt_regs *regs, long error_code) { struct task_struct *tsk; + enum ctx_state prev_state; - exception_enter(regs); + prev_state = exception_enter(); conditional_sti(regs); #ifdef CONFIG_X86_32 @@ -300,12 +306,14 @@ do_general_protection(struct pt_regs *regs, long error_code) force_sig(SIGSEGV, tsk); exit: - exception_exit(regs); + exception_exit(prev_state); } /* May run on IST stack. */ dotraplinkage void __kprobes notrace do_int3(struct pt_regs *regs, long error_code) { + enum ctx_state prev_state; + #ifdef CONFIG_DYNAMIC_FTRACE /* * ftrace must be first, everything else may cause a recursive crash. @@ -315,7 +323,7 @@ dotraplinkage void __kprobes notrace do_int3(struct pt_regs *regs, long error_co ftrace_int3_handler(regs)) return; #endif - exception_enter(regs); + prev_state = exception_enter(); #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP, SIGTRAP) == NOTIFY_STOP) @@ -336,7 +344,7 @@ dotraplinkage void __kprobes notrace do_int3(struct pt_regs *regs, long error_co preempt_conditional_cli(regs); debug_stack_usage_dec(); exit: - exception_exit(regs); + exception_exit(prev_state); } #ifdef CONFIG_X86_64 @@ -393,11 +401,12 @@ asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code) { struct task_struct *tsk = current; + enum ctx_state prev_state; int user_icebp = 0; unsigned long dr6; int si_code; - exception_enter(regs); + prev_state = exception_enter(); get_debugreg(dr6, 6); @@ -467,7 +476,7 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code) debug_stack_usage_dec(); exit: - exception_exit(regs); + exception_exit(prev_state); } /* @@ -561,17 +570,21 @@ void math_error(struct pt_regs *regs, int error_code, int trapnr) dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code) { - exception_enter(regs); + enum ctx_state prev_state; + + prev_state = exception_enter(); math_error(regs, error_code, X86_TRAP_MF); - exception_exit(regs); + exception_exit(prev_state); } dotraplinkage void do_simd_coprocessor_error(struct pt_regs *regs, long error_code) { - exception_enter(regs); + enum ctx_state prev_state; + + prev_state = exception_enter(); math_error(regs, error_code, X86_TRAP_XF); - exception_exit(regs); + exception_exit(prev_state); } dotraplinkage void @@ -639,7 +652,9 @@ EXPORT_SYMBOL_GPL(math_state_restore); dotraplinkage void __kprobes do_device_not_available(struct pt_regs *regs, long error_code) { - exception_enter(regs); + enum ctx_state prev_state; + + prev_state = exception_enter(); BUG_ON(use_eager_fpu()); #ifdef CONFIG_MATH_EMULATION @@ -650,7 +665,7 @@ do_device_not_available(struct pt_regs *regs, long error_code) info.regs = regs; math_emulate(&info); - exception_exit(regs); + exception_exit(prev_state); return; } #endif @@ -658,15 +673,16 @@ do_device_not_available(struct pt_regs *regs, long error_code) #ifdef CONFIG_X86_32 conditional_sti(regs); #endif - exception_exit(regs); + exception_exit(prev_state); } #ifdef CONFIG_X86_32 dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code) { siginfo_t info; + enum ctx_state prev_state; - exception_enter(regs); + prev_state = exception_enter(); local_irq_enable(); info.si_signo = SIGILL; @@ -678,7 +694,7 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code) do_trap(X86_TRAP_IRET, SIGILL, "iret exception", regs, error_code, &info); } - exception_exit(regs); + exception_exit(prev_state); } #endif diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 2b97525..fa8c02d 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -13,12 +13,12 @@ #include <linux/perf_event.h> /* perf_sw_event */ #include <linux/hugetlb.h> /* hstate_index_to_shift */ #include <linux/prefetch.h> /* prefetchw */ +#include <linux/context_tracking.h> /* exception_enter(), ... */ #include <asm/traps.h> /* dotraplinkage, ... */ #include <asm/pgalloc.h> /* pgd_*(), ... */ #include <asm/kmemcheck.h> /* kmemcheck_*(), ... */ #include <asm/fixmap.h> /* VSYSCALL_START */ -#include <asm/context_tracking.h> /* exception_enter(), ... */ /* * Page fault error code bits: @@ -1222,7 +1222,9 @@ good_area: dotraplinkage void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) { - exception_enter(regs); + enum ctx_state prev_state; + + prev_state = exception_enter(); __do_page_fault(regs, error_code); - exception_exit(regs); + exception_exit(prev_state); } diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h index b28d161..365f4a6 100644 --- a/include/linux/context_tracking.h +++ b/include/linux/context_tracking.h @@ -1,9 +1,9 @@ #ifndef _LINUX_CONTEXT_TRACKING_H #define _LINUX_CONTEXT_TRACKING_H -#ifdef CONFIG_CONTEXT_TRACKING #include <linux/sched.h> #include <linux/percpu.h> +#include <asm/ptrace.h> struct context_tracking { /* @@ -13,12 +13,13 @@ struct context_tracking { * may be further optimized using static keys. */ bool active; - enum { + enum ctx_state { IN_KERNEL = 0, IN_USER, } state; }; +#ifdef CONFIG_CONTEXT_TRACKING DECLARE_PER_CPU(struct context_tracking, context_tracking); static inline bool context_tracking_in_user(void) @@ -33,12 +34,31 @@ static inline bool context_tracking_active(void) extern void user_enter(void); extern void user_exit(void); + +static inline enum ctx_state exception_enter(void) +{ + enum ctx_state prev_ctx; + + prev_ctx = this_cpu_read(context_tracking.state); + user_exit(); + + return prev_ctx; +} + +static inline void exception_exit(enum ctx_state prev_ctx) +{ + if (prev_ctx == IN_USER) + user_enter(); +} + extern void context_tracking_task_switch(struct task_struct *prev, struct task_struct *next); #else static inline bool context_tracking_in_user(void) { return false; } static inline void user_enter(void) { } static inline void user_exit(void) { } +static inline enum ctx_state exception_enter(void) { return 0; } +static inline void exception_exit(enum ctx_state prev_ctx) { } static inline void context_tracking_task_switch(struct task_struct *prev, struct task_struct *next) { } #endif /* !CONFIG_CONTEXT_TRACKING */ diff --git a/include/linux/sched.h b/include/linux/sched.h index fc039ce..9004f6e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -558,7 +558,7 @@ struct signal_struct { cputime_t utime, stime, cutime, cstime; cputime_t gtime; cputime_t cgtime; -#ifndef CONFIG_VIRT_CPU_ACCOUNTING +#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE struct cputime prev_cputime; #endif unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; @@ -1158,7 +1158,7 @@ struct task_struct { cputime_t utime, stime, utimescaled, stimescaled; cputime_t gtime; -#ifndef CONFIG_VIRT_CPU_ACCOUNTING +#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE struct cputime prev_cputime; #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN diff --git a/init/Kconfig b/init/Kconfig index 22616cd..8a1dac2 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -509,6 +509,7 @@ config RCU_USER_QS config CONTEXT_TRACKING_FORCE bool "Force context tracking" depends on CONTEXT_TRACKING + default CONTEXT_TRACKING help Probe on user/kernel boundaries by default in order to test the features that rely on it such as userspace RCU extended diff --git a/kernel/fork.c b/kernel/fork.c index 8d932b1..f3146ed 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1230,7 +1230,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->utime = p->stime = p->gtime = 0; p->utimescaled = p->stimescaled = 0; -#ifndef CONFIG_VIRT_CPU_ACCOUNTING +#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE p->prev_cputime.utime = p->prev_cputime.stime = 0; #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 42ecbcb..b36635e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3082,11 +3082,13 @@ EXPORT_SYMBOL(preempt_schedule); asmlinkage void __sched preempt_schedule_irq(void) { struct thread_info *ti = current_thread_info(); + enum ctx_state prev_state; /* Catch callers which need to be fixed */ BUG_ON(ti->preempt_count || !irqs_disabled()); - user_exit(); + prev_state = exception_enter(); + do { add_preempt_count(PREEMPT_ACTIVE); local_irq_enable(); @@ -3100,6 +3102,8 @@ asmlinkage void __sched preempt_schedule_irq(void) */ barrier(); } while (need_resched()); + + exception_exit(prev_state); } #endif /* CONFIG_PREEMPT */ diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index ed12cbb..024fe19 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -388,82 +388,10 @@ static inline void irqtime_account_process_tick(struct task_struct *p, int user_ 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 - * @user_tick: indicates if the tick is a user or a system tick - */ -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; - } - - if (steal_account_process_tick()) - return; - - if (user_tick) - account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); - else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET)) - account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy, - one_jiffy_scaled); - else - account_idle_time(cputime_one_jiffy); -} - -/* - * Account multiple ticks of steal time. - * @p: the process from which the cpu time has been stolen - * @ticks: number of stolen ticks - */ -void account_steal_ticks(unsigned long ticks) -{ - account_steal_time(jiffies_to_cputime(ticks)); -} - -/* - * Account multiple ticks of idle time. - * @ticks: number of stolen ticks - */ -void account_idle_ticks(unsigned long ticks) -{ - - if (sched_clock_irqtime) { - irqtime_account_idle_ticks(ticks); - return; - } - - account_idle_time(jiffies_to_cputime(ticks)); -} -#endif /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ - /* * Use precise platform statistics if available: */ #ifdef CONFIG_VIRT_CPU_ACCOUNTING -void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) -{ - *ut = p->utime; - *st = p->stime; -} - -void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) -{ - struct task_cputime cputime; - - thread_group_cputime(p, &cputime); - - *ut = cputime.utime; - *st = cputime.stime; -} #ifndef __ARCH_HAS_VTIME_TASK_SWITCH void vtime_task_switch(struct task_struct *prev) @@ -518,8 +446,80 @@ void vtime_account_irq_enter(struct task_struct *tsk) } EXPORT_SYMBOL_GPL(vtime_account_irq_enter); #endif /* __ARCH_HAS_VTIME_ACCOUNT */ +#endif /* CONFIG_VIRT_CPU_ACCOUNTING */ + + +#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE +void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) +{ + *ut = p->utime; + *st = p->stime; +} -#else /* !CONFIG_VIRT_CPU_ACCOUNTING */ +void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) +{ + struct task_cputime cputime; + + thread_group_cputime(p, &cputime); + + *ut = cputime.utime; + *st = cputime.stime; +} +#else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ +/* + * Account a single tick of cpu time. + * @p: the process that the cpu time gets accounted to + * @user_tick: indicates if the tick is a user or a system tick + */ +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; + } + + if (steal_account_process_tick()) + return; + + if (user_tick) + account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); + else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET)) + account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy, + one_jiffy_scaled); + else + account_idle_time(cputime_one_jiffy); +} + +/* + * Account multiple ticks of steal time. + * @p: the process from which the cpu time has been stolen + * @ticks: number of stolen ticks + */ +void account_steal_ticks(unsigned long ticks) +{ + account_steal_time(jiffies_to_cputime(ticks)); +} + +/* + * Account multiple ticks of idle time. + * @ticks: number of stolen ticks + */ +void account_idle_ticks(unsigned long ticks) +{ + + if (sched_clock_irqtime) { + irqtime_account_idle_ticks(ticks); + return; + } + + account_idle_time(jiffies_to_cputime(ticks)); +} static cputime_t scale_stime(cputime_t stime, cputime_t rtime, cputime_t total) { @@ -545,6 +545,12 @@ static void cputime_adjust(struct task_cputime *curr, { cputime_t rtime, stime, total; + if (vtime_accounting_enabled()) { + *ut = curr->utime; + *st = curr->stime; + return; + } + stime = curr->stime; total = stime + curr->utime; @@ -597,7 +603,7 @@ 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 /* !CONFIG_VIRT_CPU_ACCOUNTING */ +#endif /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN static unsigned long long vtime_delta(struct task_struct *tsk) |