diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-23 16:46:15 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-23 16:46:15 (GMT) |
commit | 31bbb9b58d1e8ebcf2b28c95c2250a9f8e31e397 (patch) | |
tree | 6bb0c0490d66d32eca43e73abb28d8b3ab0e7b91 | |
parent | ff830b8e5f999d1ccbd0282a666520f0b557daa4 (diff) | |
parent | 3f0a525ebf4b8ef041a332bbe4a73aee94bb064b (diff) | |
download | linux-fsl-qoriq-31bbb9b58d1e8ebcf2b28c95c2250a9f8e31e397.tar.xz |
Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
itimers: Add tracepoints for itimer
hrtimer: Add tracepoint for hrtimers
timers: Add tracepoints for timer_list timers
cputime: Optimize jiffies_to_cputime(1)
itimers: Simplify arm_timer() code a bit
itimers: Fix periodic tics precision
itimers: Merge ITIMER_VIRT and ITIMER_PROF
Trivial header file include conflicts in kernel/fork.c
-rw-r--r-- | arch/ia64/include/asm/cputime.h | 1 | ||||
-rw-r--r-- | arch/powerpc/include/asm/cputime.h | 13 | ||||
-rw-r--r-- | arch/powerpc/kernel/time.c | 4 | ||||
-rw-r--r-- | arch/s390/include/asm/cputime.h | 1 | ||||
-rw-r--r-- | include/asm-generic/cputime.h | 1 | ||||
-rw-r--r-- | include/linux/sched.h | 16 | ||||
-rw-r--r-- | include/trace/events/timer.h | 342 | ||||
-rw-r--r-- | kernel/fork.c | 9 | ||||
-rw-r--r-- | kernel/hrtimer.c | 40 | ||||
-rw-r--r-- | kernel/itimer.c | 169 | ||||
-rw-r--r-- | kernel/posix-cpu-timers.c | 155 | ||||
-rw-r--r-- | kernel/sched.c | 9 | ||||
-rw-r--r-- | kernel/timer.c | 32 |
13 files changed, 620 insertions, 172 deletions
diff --git a/arch/ia64/include/asm/cputime.h b/arch/ia64/include/asm/cputime.h index d20b998..7fa8a85 100644 --- a/arch/ia64/include/asm/cputime.h +++ b/arch/ia64/include/asm/cputime.h @@ -30,6 +30,7 @@ typedef u64 cputime_t; typedef u64 cputime64_t; #define cputime_zero ((cputime_t)0) +#define cputime_one_jiffy jiffies_to_cputime(1) #define cputime_max ((~((cputime_t)0) >> 1) - 1) #define cputime_add(__a, __b) ((__a) + (__b)) #define cputime_sub(__a, __b) ((__a) - (__b)) diff --git a/arch/powerpc/include/asm/cputime.h b/arch/powerpc/include/asm/cputime.h index f42e623..fa19f3f 100644 --- a/arch/powerpc/include/asm/cputime.h +++ b/arch/powerpc/include/asm/cputime.h @@ -18,6 +18,9 @@ #ifndef CONFIG_VIRT_CPU_ACCOUNTING #include <asm-generic/cputime.h> +#ifdef __KERNEL__ +static inline void setup_cputime_one_jiffy(void) { } +#endif #else #include <linux/types.h> @@ -49,6 +52,11 @@ typedef u64 cputime64_t; #ifdef __KERNEL__ /* + * One jiffy in timebase units computed during initialization + */ +extern cputime_t cputime_one_jiffy; + +/* * Convert cputime <-> jiffies */ extern u64 __cputime_jiffies_factor; @@ -89,6 +97,11 @@ static inline cputime_t jiffies_to_cputime(const unsigned long jif) return ct; } +static inline void setup_cputime_one_jiffy(void) +{ + cputime_one_jiffy = jiffies_to_cputime(1); +} + static inline cputime64_t jiffies64_to_cputime64(const u64 jif) { cputime_t ct; diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index df45a74..92dc844 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -193,6 +193,8 @@ EXPORT_SYMBOL(__cputime_clockt_factor); DEFINE_PER_CPU(unsigned long, cputime_last_delta); DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta); +cputime_t cputime_one_jiffy; + static void calc_cputime_factors(void) { struct div_result res; @@ -501,6 +503,7 @@ static int __init iSeries_tb_recal(void) tb_to_xs = divres.result_low; vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; vdso_data->tb_to_xs = tb_to_xs; + setup_cputime_one_jiffy(); } else { printk( "Titan recalibrate: FAILED (difference > 4 percent)\n" @@ -960,6 +963,7 @@ void __init time_init(void) tb_ticks_per_usec = ppc_tb_freq / 1000000; tb_to_us = mulhwu_scale_factor(ppc_tb_freq, 1000000); calc_cputime_factors(); + setup_cputime_one_jiffy(); /* * Calculate the length of each tick in ns. It will not be diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index 7a3817a..24b1244 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -42,6 +42,7 @@ __div(unsigned long long n, unsigned int base) #endif /* __s390x__ */ #define cputime_zero (0ULL) +#define cputime_one_jiffy jiffies_to_cputime(1) #define cputime_max ((~0UL >> 1) - 1) #define cputime_add(__a, __b) ((__a) + (__b)) #define cputime_sub(__a, __b) ((__a) - (__b)) diff --git a/include/asm-generic/cputime.h b/include/asm-generic/cputime.h index 1c1fa42..ca0f239 100644 --- a/include/asm-generic/cputime.h +++ b/include/asm-generic/cputime.h @@ -7,6 +7,7 @@ typedef unsigned long cputime_t; #define cputime_zero (0UL) +#define cputime_one_jiffy jiffies_to_cputime(1) #define cputime_max ((~0UL >> 1) - 1) #define cputime_add(__a, __b) ((__a) + (__b)) #define cputime_sub(__a, __b) ((__a) - (__b)) diff --git a/include/linux/sched.h b/include/linux/sched.h index 3cbc6c0..cbf2a3b 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -493,6 +493,13 @@ struct pacct_struct { unsigned long ac_minflt, ac_majflt; }; +struct cpu_itimer { + cputime_t expires; + cputime_t incr; + u32 error; + u32 incr_error; +}; + /** * struct task_cputime - collected CPU time counts * @utime: time spent in user mode, in &cputime_t units @@ -587,9 +594,12 @@ struct signal_struct { struct pid *leader_pid; ktime_t it_real_incr; - /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */ - cputime_t it_prof_expires, it_virt_expires; - cputime_t it_prof_incr, it_virt_incr; + /* + * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use + * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these + * values are defined to 0 and 1 respectively + */ + struct cpu_itimer it[2]; /* * Thread group totals for process CPU timers. diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h new file mode 100644 index 0000000..1844c48 --- /dev/null +++ b/include/trace/events/timer.h @@ -0,0 +1,342 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM timer + +#if !defined(_TRACE_TIMER_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_TIMER_H + +#include <linux/tracepoint.h> +#include <linux/hrtimer.h> +#include <linux/timer.h> + +/** + * timer_init - called when the timer is initialized + * @timer: pointer to struct timer_list + */ +TRACE_EVENT(timer_init, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("timer %p", __entry->timer) +); + +/** + * timer_start - called when the timer is started + * @timer: pointer to struct timer_list + * @expires: the timers expiry time + */ +TRACE_EVENT(timer_start, + + TP_PROTO(struct timer_list *timer, unsigned long expires), + + TP_ARGS(timer, expires), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( void *, function ) + __field( unsigned long, expires ) + __field( unsigned long, now ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->function = timer->function; + __entry->expires = expires; + __entry->now = jiffies; + ), + + TP_printk("timer %p: func %pf, expires %lu, timeout %ld", + __entry->timer, __entry->function, __entry->expires, + (long)__entry->expires - __entry->now) +); + +/** + * timer_expire_entry - called immediately before the timer callback + * @timer: pointer to struct timer_list + * + * Allows to determine the timer latency. + */ +TRACE_EVENT(timer_expire_entry, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( unsigned long, now ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->now = jiffies; + ), + + TP_printk("timer %p: now %lu", __entry->timer, __entry->now) +); + +/** + * timer_expire_exit - called immediately after the timer callback returns + * @timer: pointer to struct timer_list + * + * When used in combination with the timer_expire_entry tracepoint we can + * determine the runtime of the timer callback function. + * + * NOTE: Do NOT derefernce timer in TP_fast_assign. The pointer might + * be invalid. We solely track the pointer. + */ +TRACE_EVENT(timer_expire_exit, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field(void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("timer %p", __entry->timer) +); + +/** + * timer_cancel - called when the timer is canceled + * @timer: pointer to struct timer_list + */ +TRACE_EVENT(timer_cancel, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("timer %p", __entry->timer) +); + +/** + * hrtimer_init - called when the hrtimer is initialized + * @timer: pointer to struct hrtimer + * @clockid: the hrtimers clock + * @mode: the hrtimers mode + */ +TRACE_EVENT(hrtimer_init, + + TP_PROTO(struct hrtimer *timer, clockid_t clockid, + enum hrtimer_mode mode), + + TP_ARGS(timer, clockid, mode), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( clockid_t, clockid ) + __field( enum hrtimer_mode, mode ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->clockid = clockid; + __entry->mode = mode; + ), + + TP_printk("hrtimer %p, clockid %s, mode %s", __entry->timer, + __entry->clockid == CLOCK_REALTIME ? + "CLOCK_REALTIME" : "CLOCK_MONOTONIC", + __entry->mode == HRTIMER_MODE_ABS ? + "HRTIMER_MODE_ABS" : "HRTIMER_MODE_REL") +); + +/** + * hrtimer_start - called when the hrtimer is started + * @timer: pointer to struct hrtimer + */ +TRACE_EVENT(hrtimer_start, + + TP_PROTO(struct hrtimer *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( void *, function ) + __field( s64, expires ) + __field( s64, softexpires ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->function = timer->function; + __entry->expires = hrtimer_get_expires(timer).tv64; + __entry->softexpires = hrtimer_get_softexpires(timer).tv64; + ), + + TP_printk("hrtimer %p, func %pf, expires %llu, softexpires %llu", + __entry->timer, __entry->function, + (unsigned long long)ktime_to_ns((ktime_t) { + .tv64 = __entry->expires }), + (unsigned long long)ktime_to_ns((ktime_t) { + .tv64 = __entry->softexpires })) +); + +/** + * htimmer_expire_entry - called immediately before the hrtimer callback + * @timer: pointer to struct hrtimer + * @now: pointer to variable which contains current time of the + * timers base. + * + * Allows to determine the timer latency. + */ +TRACE_EVENT(hrtimer_expire_entry, + + TP_PROTO(struct hrtimer *timer, ktime_t *now), + + TP_ARGS(timer, now), + + TP_STRUCT__entry( + __field( void *, timer ) + __field( s64, now ) + ), + + TP_fast_assign( + __entry->timer = timer; + __entry->now = now->tv64; + ), + + TP_printk("hrtimer %p, now %llu", __entry->timer, + (unsigned long long)ktime_to_ns((ktime_t) { + .tv64 = __entry->now })) + ); + +/** + * hrtimer_expire_exit - called immediately after the hrtimer callback returns + * @timer: pointer to struct hrtimer + * + * When used in combination with the hrtimer_expire_entry tracepoint we can + * determine the runtime of the callback function. + */ +TRACE_EVENT(hrtimer_expire_exit, + + TP_PROTO(struct hrtimer *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("hrtimer %p", __entry->timer) +); + +/** + * hrtimer_cancel - called when the hrtimer is canceled + * @timer: pointer to struct hrtimer + */ +TRACE_EVENT(hrtimer_cancel, + + TP_PROTO(struct hrtimer *timer), + + TP_ARGS(timer), + + TP_STRUCT__entry( + __field( void *, timer ) + ), + + TP_fast_assign( + __entry->timer = timer; + ), + + TP_printk("hrtimer %p", __entry->timer) +); + +/** + * itimer_state - called when itimer is started or canceled + * @which: name of the interval timer + * @value: the itimers value, itimer is canceled if value->it_value is + * zero, otherwise it is started + * @expires: the itimers expiry time + */ +TRACE_EVENT(itimer_state, + + TP_PROTO(int which, const struct itimerval *const value, + cputime_t expires), + + TP_ARGS(which, value, expires), + + TP_STRUCT__entry( + __field( int, which ) + __field( cputime_t, expires ) + __field( long, value_sec ) + __field( long, value_usec ) + __field( long, interval_sec ) + __field( long, interval_usec ) + ), + + TP_fast_assign( + __entry->which = which; + __entry->expires = expires; + __entry->value_sec = value->it_value.tv_sec; + __entry->value_usec = value->it_value.tv_usec; + __entry->interval_sec = value->it_interval.tv_sec; + __entry->interval_usec = value->it_interval.tv_usec; + ), + + TP_printk("which %d, expires %lu, it_value %lu.%lu, it_interval %lu.%lu", + __entry->which, __entry->expires, + __entry->value_sec, __entry->value_usec, + __entry->interval_sec, __entry->interval_usec) +); + +/** + * itimer_expire - called when itimer expires + * @which: type of the interval timer + * @pid: pid of the process which owns the timer + * @now: current time, used to calculate the latency of itimer + */ +TRACE_EVENT(itimer_expire, + + TP_PROTO(int which, struct pid *pid, cputime_t now), + + TP_ARGS(which, pid, now), + + TP_STRUCT__entry( + __field( int , which ) + __field( pid_t, pid ) + __field( cputime_t, now ) + ), + + TP_fast_assign( + __entry->which = which; + __entry->now = now; + __entry->pid = pid_nr(pid); + ), + + TP_printk("which %d, pid %d, now %lu", __entry->which, + (int) __entry->pid, __entry->now) +); + +#endif /* _TRACE_TIMER_H */ + +/* This part must be outside protection */ +#include <trace/define_trace.h> diff --git a/kernel/fork.c b/kernel/fork.c index 8f45b0e..51ad0b0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -63,6 +63,7 @@ #include <linux/fs_struct.h> #include <linux/magic.h> #include <linux/perf_event.h> +#include <linux/posix-timers.h> #include <asm/pgtable.h> #include <asm/pgalloc.h> @@ -805,10 +806,10 @@ static void posix_cpu_timers_init_group(struct signal_struct *sig) thread_group_cputime_init(sig); /* Expiration times and increments. */ - sig->it_virt_expires = cputime_zero; - sig->it_virt_incr = cputime_zero; - sig->it_prof_expires = cputime_zero; - sig->it_prof_incr = cputime_zero; + sig->it[CPUCLOCK_PROF].expires = cputime_zero; + sig->it[CPUCLOCK_PROF].incr = cputime_zero; + sig->it[CPUCLOCK_VIRT].expires = cputime_zero; + sig->it[CPUCLOCK_VIRT].incr = cputime_zero; /* Cached expiration times. */ sig->cputime_expires.prof_exp = cputime_zero; diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index c03f221..e5d98ce 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -48,6 +48,8 @@ #include <asm/uaccess.h> +#include <trace/events/timer.h> + /* * The timer bases: * @@ -442,6 +444,26 @@ static inline void debug_hrtimer_activate(struct hrtimer *timer) { } static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { } #endif +static inline void +debug_init(struct hrtimer *timer, clockid_t clockid, + enum hrtimer_mode mode) +{ + debug_hrtimer_init(timer); + trace_hrtimer_init(timer, clockid, mode); +} + +static inline void debug_activate(struct hrtimer *timer) +{ + debug_hrtimer_activate(timer); + trace_hrtimer_start(timer); +} + +static inline void debug_deactivate(struct hrtimer *timer) +{ + debug_hrtimer_deactivate(timer); + trace_hrtimer_cancel(timer); +} + /* High resolution timer related functions */ #ifdef CONFIG_HIGH_RES_TIMERS @@ -798,7 +820,7 @@ static int enqueue_hrtimer(struct hrtimer *timer, struct hrtimer *entry; int leftmost = 1; - debug_hrtimer_activate(timer); + debug_activate(timer); /* * Find the right place in the rbtree: @@ -884,7 +906,7 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base) * reprogramming happens in the interrupt handler. This is a * rare case and less expensive than a smp call. */ - debug_hrtimer_deactivate(timer); + debug_deactivate(timer); timer_stats_hrtimer_clear_start_info(timer); reprogram = base->cpu_base == &__get_cpu_var(hrtimer_bases); __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, @@ -1117,7 +1139,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, void hrtimer_init(struct hrtimer *timer, clockid_t clock_id, enum hrtimer_mode mode) { - debug_hrtimer_init(timer); + debug_init(timer, clock_id, mode); __hrtimer_init(timer, clock_id, mode); } EXPORT_SYMBOL_GPL(hrtimer_init); @@ -1141,7 +1163,7 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp) } EXPORT_SYMBOL_GPL(hrtimer_get_res); -static void __run_hrtimer(struct hrtimer *timer) +static void __run_hrtimer(struct hrtimer *timer, ktime_t *now) { struct hrtimer_clock_base *base = timer->base; struct hrtimer_cpu_base *cpu_base = base->cpu_base; @@ -1150,7 +1172,7 @@ static void __run_hrtimer(struct hrtimer *timer) WARN_ON(!irqs_disabled()); - debug_hrtimer_deactivate(timer); + debug_deactivate(timer); __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0); timer_stats_account_hrtimer(timer); fn = timer->function; @@ -1161,7 +1183,9 @@ static void __run_hrtimer(struct hrtimer *timer) * the timer base. */ spin_unlock(&cpu_base->lock); + trace_hrtimer_expire_entry(timer, now); restart = fn(timer); + trace_hrtimer_expire_exit(timer); spin_lock(&cpu_base->lock); /* @@ -1272,7 +1296,7 @@ void hrtimer_interrupt(struct clock_event_device *dev) break; } - __run_hrtimer(timer); + __run_hrtimer(timer, &basenow); } base++; } @@ -1394,7 +1418,7 @@ void hrtimer_run_queues(void) hrtimer_get_expires_tv64(timer)) break; - __run_hrtimer(timer); + __run_hrtimer(timer, &base->softirq_time); } spin_unlock(&cpu_base->lock); } @@ -1571,7 +1595,7 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, while ((node = rb_first(&old_base->active))) { timer = rb_entry(node, struct hrtimer, node); BUG_ON(hrtimer_callback_running(timer)); - debug_hrtimer_deactivate(timer); + debug_deactivate(timer); /* * Mark it as STATE_MIGRATE not INACTIVE otherwise the diff --git a/kernel/itimer.c b/kernel/itimer.c index 58762f7..b03451e 100644 --- a/kernel/itimer.c +++ b/kernel/itimer.c @@ -12,6 +12,7 @@ #include <linux/time.h> #include <linux/posix-timers.h> #include <linux/hrtimer.h> +#include <trace/events/timer.h> #include <asm/uaccess.h> @@ -41,10 +42,43 @@ static struct timeval itimer_get_remtime(struct hrtimer *timer) return ktime_to_timeval(rem); } +static void get_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, + struct itimerval *const value) +{ + cputime_t cval, cinterval; + struct cpu_itimer *it = &tsk->signal->it[clock_id]; + + spin_lock_irq(&tsk->sighand->siglock); + + cval = it->expires; + cinterval = it->incr; + if (!cputime_eq(cval, cputime_zero)) { + struct task_cputime cputime; + cputime_t t; + + thread_group_cputimer(tsk, &cputime); + if (clock_id == CPUCLOCK_PROF) + t = cputime_add(cputime.utime, cputime.stime); + else + /* CPUCLOCK_VIRT */ + t = cputime.utime; + + if (cputime_le(cval, t)) + /* about to fire */ + cval = cputime_one_jiffy; + else + cval = cputime_sub(cval, t); + } + + spin_unlock_irq(&tsk->sighand->siglock); + + cputime_to_timeval(cval, &value->it_value); + cputime_to_timeval(cinterval, &value->it_interval); +} + int do_getitimer(int which, struct itimerval *value) { struct task_struct *tsk = current; - cputime_t cinterval, cval; switch (which) { case ITIMER_REAL: @@ -55,44 +89,10 @@ int do_getitimer(int which, struct itimerval *value) spin_unlock_irq(&tsk->sighand->siglock); break; case ITIMER_VIRTUAL: - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_virt_expires; - cinterval = tsk->signal->it_virt_incr; - if (!cputime_eq(cval, cputime_zero)) { - struct task_cputime cputime; - cputime_t utime; - - thread_group_cputimer(tsk, &cputime); - utime = cputime.utime; - if (cputime_le(cval, utime)) { /* about to fire */ - cval = jiffies_to_cputime(1); - } else { - cval = cputime_sub(cval, utime); - } - } - spin_unlock_irq(&tsk->sighand->siglock); - cputime_to_timeval(cval, &value->it_value); - cputime_to_timeval(cinterval, &value->it_interval); + get_cpu_itimer(tsk, CPUCLOCK_VIRT, value); break; case ITIMER_PROF: - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_prof_expires; - cinterval = tsk->signal->it_prof_incr; - if (!cputime_eq(cval, cputime_zero)) { - struct task_cputime times; - cputime_t ptime; - - thread_group_cputimer(tsk, ×); - ptime = cputime_add(times.utime, times.stime); - if (cputime_le(cval, ptime)) { /* about to fire */ - cval = jiffies_to_cputime(1); - } else { - cval = cputime_sub(cval, ptime); - } - } - spin_unlock_irq(&tsk->sighand->siglock); - cputime_to_timeval(cval, &value->it_value); - cputime_to_timeval(cinterval, &value->it_interval); + get_cpu_itimer(tsk, CPUCLOCK_PROF, value); break; default: return(-EINVAL); @@ -123,11 +123,62 @@ enum hrtimer_restart it_real_fn(struct hrtimer *timer) struct signal_struct *sig = container_of(timer, struct signal_struct, real_timer); + trace_itimer_expire(ITIMER_REAL, sig->leader_pid, 0); kill_pid_info(SIGALRM, SEND_SIG_PRIV, sig->leader_pid); return HRTIMER_NORESTART; } +static inline u32 cputime_sub_ns(cputime_t ct, s64 real_ns) +{ + struct timespec ts; + s64 cpu_ns; + + cputime_to_timespec(ct, &ts); + cpu_ns = timespec_to_ns(&ts); + + return (cpu_ns <= real_ns) ? 0 : cpu_ns - real_ns; +} + +static void set_cpu_itimer(struct task_struct *tsk, unsigned int clock_id, + const struct itimerval *const value, + struct itimerval *const ovalue) +{ + cputime_t cval, nval, cinterval, ninterval; + s64 ns_ninterval, ns_nval; + struct cpu_itimer *it = &tsk->signal->it[clock_id]; + + nval = timeval_to_cputime(&value->it_value); + ns_nval = timeval_to_ns(&value->it_value); + ninterval = timeval_to_cputime(&value->it_interval); + ns_ninterval = timeval_to_ns(&value->it_interval); + + it->incr_error = cputime_sub_ns(ninterval, ns_ninterval); + it->error = cputime_sub_ns(nval, ns_nval); + + spin_lock_irq(&tsk->sighand->siglock); + + cval = it->expires; + cinterval = it->incr; + if (!cputime_eq(cval, cputime_zero) || + !cputime_eq(nval, cputime_zero)) { + if (cputime_gt(nval, cputime_zero)) + nval = cputime_add(nval, cputime_one_jiffy); + set_process_cpu_timer(tsk, clock_id, &nval, &cval); + } + it->expires = nval; + it->incr = ninterval; + trace_itimer_state(clock_id == CPUCLOCK_VIRT ? + ITIMER_VIRTUAL : ITIMER_PROF, value, nval); + + spin_unlock_irq(&tsk->sighand->siglock); + + if (ovalue) { + cputime_to_timeval(cval, &ovalue->it_value); + cputime_to_timeval(cinterval, &ovalue->it_interval); + } +} + /* * Returns true if the timeval is in canonical form */ @@ -139,7 +190,6 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue) struct task_struct *tsk = current; struct hrtimer *timer; ktime_t expires; - cputime_t cval, cinterval, nval, ninterval; /* * Validate the timevals in value. @@ -171,51 +221,14 @@ again: } else tsk->signal->it_real_incr.tv64 = 0; + trace_itimer_state(ITIMER_REAL, value, 0); spin_unlock_irq(&tsk->sighand->siglock); break; case ITIMER_VIRTUAL: - nval = timeval_to_cputime(&value->it_value); - ninterval = timeval_to_cputime(&value->it_interval); - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_virt_expires; - cinterval = tsk->signal->it_virt_incr; - if (!cputime_eq(cval, cputime_zero) || - !cputime_eq(nval, cputime_zero)) { - if (cputime_gt(nval, cputime_zero)) - nval = cputime_add(nval, - jiffies_to_cputime(1)); - set_process_cpu_timer(tsk, CPUCLOCK_VIRT, - &nval, &cval); - } - tsk->signal->it_virt_expires = nval; - tsk->signal->it_virt_incr = ninterval; - spin_unlock_irq(&tsk->sighand->siglock); - if (ovalue) { - cputime_to_timeval(cval, &ovalue->it_value); - cputime_to_timeval(cinterval, &ovalue->it_interval); - } + set_cpu_itimer(tsk, CPUCLOCK_VIRT, value, ovalue); break; case ITIMER_PROF: - nval = timeval_to_cputime(&value->it_value); - ninterval = timeval_to_cputime(&value->it_interval); - spin_lock_irq(&tsk->sighand->siglock); - cval = tsk->signal->it_prof_expires; - cinterval = tsk->signal->it_prof_incr; - if (!cputime_eq(cval, cputime_zero) || - !cputime_eq(nval, cputime_zero)) { - if (cputime_gt(nval, cputime_zero)) - nval = cputime_add(nval, - jiffies_to_cputime(1)); - set_process_cpu_timer(tsk, CPUCLOCK_PROF, - &nval, &cval); - } - tsk->signal->it_prof_expires = nval; - tsk->signal->it_prof_incr = ninterval; - spin_unlock_irq(&tsk->sighand->siglock); - if (ovalue) { - cputime_to_timeval(cval, &ovalue->it_value); - cputime_to_timeval(cinterval, &ovalue->it_interval); - } + set_cpu_itimer(tsk, CPUCLOCK_PROF, value, ovalue); break; default: return -EINVAL; diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index e33a21c..5c9dc22 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -8,17 +8,18 @@ #include <linux/math64.h> #include <asm/uaccess.h> #include <linux/kernel_stat.h> +#include <trace/events/timer.h> /* * Called after updating RLIMIT_CPU to set timer expiration if necessary. */ void update_rlimit_cpu(unsigned long rlim_new) { - cputime_t cputime; + cputime_t cputime = secs_to_cputime(rlim_new); + struct signal_struct *const sig = current->signal; - cputime = secs_to_cputime(rlim_new); - if (cputime_eq(current->signal->it_prof_expires, cputime_zero) || - cputime_gt(current->signal->it_prof_expires, cputime)) { + if (cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) || + cputime_gt(sig->it[CPUCLOCK_PROF].expires, cputime)) { spin_lock_irq(¤t->sighand->siglock); set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL); spin_unlock_irq(¤t->sighand->siglock); @@ -542,6 +543,17 @@ static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) now); } +static inline int expires_gt(cputime_t expires, cputime_t new_exp) +{ + return cputime_eq(expires, cputime_zero) || + cputime_gt(expires, new_exp); +} + +static inline int expires_le(cputime_t expires, cputime_t new_exp) +{ + return !cputime_eq(expires, cputime_zero) && + cputime_le(expires, new_exp); +} /* * Insert the timer on the appropriate list before any timers that * expire later. This must be called with the tasklist_lock held @@ -586,34 +598,32 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now) */ if (CPUCLOCK_PERTHREAD(timer->it_clock)) { + union cpu_time_count *exp = &nt->expires; + switch (CPUCLOCK_WHICH(timer->it_clock)) { default: BUG(); case CPUCLOCK_PROF: - if (cputime_eq(p->cputime_expires.prof_exp, - cputime_zero) || - cputime_gt(p->cputime_expires.prof_exp, - nt->expires.cpu)) - p->cputime_expires.prof_exp = - nt->expires.cpu; + if (expires_gt(p->cputime_expires.prof_exp, + exp->cpu)) + p->cputime_expires.prof_exp = exp->cpu; break; case CPUCLOCK_VIRT: - if (cputime_eq(p->cputime_expires.virt_exp, - cputime_zero) || - cputime_gt(p->cputime_expires.virt_exp, - nt->expires.cpu)) - p->cputime_expires.virt_exp = - nt->expires.cpu; + if (expires_gt(p->cputime_expires.virt_exp, + exp->cpu)) + p->cputime_expires.virt_exp = exp->cpu; break; case CPUCLOCK_SCHED: if (p->cputime_expires.sched_exp == 0 || - p->cputime_expires.sched_exp > - nt->expires.sched) + p->cputime_expires.sched_exp > exp->sched) p->cputime_expires.sched_exp = - nt->expires.sched; + exp->sched; break; } } else { + struct signal_struct *const sig = p->signal; + union cpu_time_count *exp = &timer->it.cpu.expires; + /* * For a process timer, set the cached expiration time. */ @@ -621,30 +631,23 @@ static void arm_timer(struct k_itimer *timer, union cpu_time_count now) default: BUG(); case CPUCLOCK_VIRT: - if (!cputime_eq(p->signal->it_virt_expires, - cputime_zero) && - cputime_lt(p->signal->it_virt_expires, - timer->it.cpu.expires.cpu)) + if (expires_le(sig->it[CPUCLOCK_VIRT].expires, + exp->cpu)) break; - p->signal->cputime_expires.virt_exp = - timer->it.cpu.expires.cpu; + sig->cputime_expires.virt_exp = exp->cpu; break; case CPUCLOCK_PROF: - if (!cputime_eq(p->signal->it_prof_expires, - cputime_zero) && - cputime_lt(p->signal->it_prof_expires, - timer->it.cpu.expires.cpu)) + if (expires_le(sig->it[CPUCLOCK_PROF].expires, + exp->cpu)) break; - i = p->signal->rlim[RLIMIT_CPU].rlim_cur; + i = sig->rlim[RLIMIT_CPU].rlim_cur; if (i != RLIM_INFINITY && - i <= cputime_to_secs(timer->it.cpu.expires.cpu)) + i <= cputime_to_secs(exp->cpu)) break; - p->signal->cputime_expires.prof_exp = - timer->it.cpu.expires.cpu; + sig->cputime_expires.prof_exp = exp->cpu; break; case CPUCLOCK_SCHED: - p->signal->cputime_expires.sched_exp = - timer->it.cpu.expires.sched; + sig->cputime_expires.sched_exp = exp->sched; break; } } @@ -1071,6 +1074,40 @@ static void stop_process_timers(struct task_struct *tsk) spin_unlock_irqrestore(&cputimer->lock, flags); } +static u32 onecputick; + +static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, + cputime_t *expires, cputime_t cur_time, int signo) +{ + if (cputime_eq(it->expires, cputime_zero)) + return; + + if (cputime_ge(cur_time, it->expires)) { + if (!cputime_eq(it->incr, cputime_zero)) { + it->expires = cputime_add(it->expires, it->incr); + it->error += it->incr_error; + if (it->error >= onecputick) { + it->expires = cputime_sub(it->expires, + cputime_one_jiffy); + it->error -= onecputick; + } + } else { + it->expires = cputime_zero; + } + + trace_itimer_expire(signo == SIGPROF ? + ITIMER_PROF : ITIMER_VIRTUAL, + tsk->signal->leader_pid, cur_time); + __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); + } + + if (!cputime_eq(it->expires, cputime_zero) && + (cputime_eq(*expires, cputime_zero) || + cputime_lt(it->expires, *expires))) { + *expires = it->expires; + } +} + /* * Check for any per-thread CPU timers that have fired and move them * off the tsk->*_timers list onto the firing list. Per-thread timers @@ -1090,10 +1127,10 @@ static void check_process_timers(struct task_struct *tsk, * Don't sample the current process CPU clocks if there are no timers. */ if (list_empty(&timers[CPUCLOCK_PROF]) && - cputime_eq(sig->it_prof_expires, cputime_zero) && + cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) && sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY && list_empty(&timers[CPUCLOCK_VIRT]) && - cputime_eq(sig->it_virt_expires, cputime_zero) && + cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) && list_empty(&timers[CPUCLOCK_SCHED])) { stop_process_timers(tsk); return; @@ -1153,38 +1190,11 @@ static void check_process_timers(struct task_struct *tsk, /* * Check for the special case process timers. */ - if (!cputime_eq(sig->it_prof_expires, cputime_zero)) { - if (cputime_ge(ptime, sig->it_prof_expires)) { - /* ITIMER_PROF fires and reloads. */ - sig->it_prof_expires = sig->it_prof_incr; - if (!cputime_eq(sig->it_prof_expires, cputime_zero)) { - sig->it_prof_expires = cputime_add( - sig->it_prof_expires, ptime); - } - __group_send_sig_info(SIGPROF, SEND_SIG_PRIV, tsk); - } - if (!cputime_eq(sig->it_prof_expires, cputime_zero) && - (cputime_eq(prof_expires, cputime_zero) || - cputime_lt(sig->it_prof_expires, prof_expires))) { - prof_expires = sig->it_prof_expires; - } - } - if (!cputime_eq(sig->it_virt_expires, cputime_zero)) { - if (cputime_ge(utime, sig->it_virt_expires)) { - /* ITIMER_VIRTUAL fires and reloads. */ - sig->it_virt_expires = sig->it_virt_incr; - if (!cputime_eq(sig->it_virt_expires, cputime_zero)) { - sig->it_virt_expires = cputime_add( - sig->it_virt_expires, utime); - } - __group_send_sig_info(SIGVTALRM, SEND_SIG_PRIV, tsk); - } - if (!cputime_eq(sig->it_virt_expires, cputime_zero) && - (cputime_eq(virt_expires, cputime_zero) || - cputime_lt(sig->it_virt_expires, virt_expires))) { - virt_expires = sig->it_virt_expires; - } - } + check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime, + SIGPROF); + check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime, + SIGVTALRM); + if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { unsigned long psecs = cputime_to_secs(ptime); cputime_t x; @@ -1457,7 +1467,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, if (!cputime_eq(*oldval, cputime_zero)) { if (cputime_le(*oldval, now.cpu)) { /* Just about to fire. */ - *oldval = jiffies_to_cputime(1); + *oldval = cputime_one_jiffy; } else { *oldval = cputime_sub(*oldval, now.cpu); } @@ -1703,10 +1713,15 @@ static __init int init_posix_cpu_timers(void) .nsleep = thread_cpu_nsleep, .nsleep_restart = thread_cpu_nsleep_restart, }; + struct timespec ts; register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process); register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread); + cputime_to_timespec(cputime_one_jiffy, &ts); + onecputick = ts.tv_nsec; + WARN_ON(ts.tv_sec != 0); + return 0; } __initcall(init_posix_cpu_timers); diff --git a/kernel/sched.c b/kernel/sched.c index 0ac9053..2f76e06b 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -5092,17 +5092,16 @@ void account_idle_time(cputime_t cputime) */ void account_process_tick(struct task_struct *p, int user_tick) { - cputime_t one_jiffy = jiffies_to_cputime(1); - cputime_t one_jiffy_scaled = cputime_to_scaled(one_jiffy); + cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); struct rq *rq = this_rq(); if (user_tick) - account_user_time(p, one_jiffy, one_jiffy_scaled); + 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, one_jiffy, + account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy, one_jiffy_scaled); else - account_idle_time(one_jiffy); + account_idle_time(cputime_one_jiffy); } /* diff --git a/kernel/timer.c b/kernel/timer.c index 811e5c3..5db5a8d 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -46,6 +46,9 @@ #include <asm/timex.h> #include <asm/io.h> +#define CREATE_TRACE_POINTS +#include <trace/events/timer.h> + u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES; EXPORT_SYMBOL(jiffies_64); @@ -521,6 +524,25 @@ static inline void debug_timer_activate(struct timer_list *timer) { } static inline void debug_timer_deactivate(struct timer_list *timer) { } #endif +static inline void debug_init(struct timer_list *timer) +{ + debug_timer_init(timer); + trace_timer_init(timer); +} + +static inline void +debug_activate(struct timer_list *timer, unsigned long expires) +{ + debug_timer_activate(timer); + trace_timer_start(timer, expires); +} + +static inline void debug_deactivate(struct timer_list *timer) +{ + debug_timer_deactivate(timer); + trace_timer_cancel(timer); +} + static void __init_timer(struct timer_list *timer, const char *name, struct lock_class_key *key) @@ -549,7 +571,7 @@ void init_timer_key(struct timer_list *timer, const char *name, struct lock_class_key *key) { - debug_timer_init(timer); + debug_init(timer); __init_timer(timer, name, key); } EXPORT_SYMBOL(init_timer_key); @@ -568,7 +590,7 @@ static inline void detach_timer(struct timer_list *timer, { struct list_head *entry = &timer->entry; - debug_timer_deactivate(timer); + debug_deactivate(timer); __list_del(entry->prev, entry->next); if (clear_pending) @@ -632,7 +654,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, goto out_unlock; } - debug_timer_activate(timer); + debug_activate(timer, expires); new_base = __get_cpu_var(tvec_bases); @@ -787,7 +809,7 @@ void add_timer_on(struct timer_list *timer, int cpu) BUG_ON(timer_pending(timer) || !timer->function); spin_lock_irqsave(&base->lock, flags); timer_set_base(timer, base); - debug_timer_activate(timer); + debug_activate(timer, timer->expires); if (time_before(timer->expires, base->next_timer) && !tbase_get_deferrable(timer->base)) base->next_timer = timer->expires; @@ -1000,7 +1022,9 @@ static inline void __run_timers(struct tvec_base *base) */ lock_map_acquire(&lockdep_map); + trace_timer_expire_entry(timer); fn(data); + trace_timer_expire_exit(timer); lock_map_release(&lockdep_map); |