linux_dsm_epyc7002/include/trace/events/timer.h
Anna-Maria Gleixner f28d3d5346 timer/trace: Improve timer tracing
Timers are added to the timer wheel off by one. This is required in
case a timer is queued directly before incrementing jiffies to prevent
early timer expiry.

When reading a timer trace and relying only on the expiry time of the timer
in the timer_start trace point and on the now in the timer_expiry_entry
trace point, it seems that the timer fires late. With the current
timer_expiry_entry trace point information only now=jiffies is printed but
not the value of base->clk. This makes it impossible to draw a conclusion
to the index of base->clk and makes it impossible to examine timer problems
without additional trace points.

Therefore add the base->clk value to the timer_expire_entry trace
point, to be able to calculate the index the timer base is located at
during collecting expired timers.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: fweisbec@gmail.com
Cc: peterz@infradead.org
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20190321120921.16463-5-anna-maria@linutronix.de
2019-03-24 20:29:33 +01:00

422 lines
10 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#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>
DECLARE_EVENT_CLASS(timer_class,
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_init - called when the timer is initialized
* @timer: pointer to struct timer_list
*/
DEFINE_EVENT(timer_class, timer_init,
TP_PROTO(struct timer_list *timer),
TP_ARGS(timer)
);
#define decode_timer_flags(flags) \
__print_flags(flags, "|", \
{ TIMER_MIGRATING, "M" }, \
{ TIMER_DEFERRABLE, "D" }, \
{ TIMER_PINNED, "P" }, \
{ TIMER_IRQSAFE, "I" })
/**
* 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,
unsigned int flags),
TP_ARGS(timer, expires, flags),
TP_STRUCT__entry(
__field( void *, timer )
__field( void *, function )
__field( unsigned long, expires )
__field( unsigned long, now )
__field( unsigned int, flags )
),
TP_fast_assign(
__entry->timer = timer;
__entry->function = timer->function;
__entry->expires = expires;
__entry->now = jiffies;
__entry->flags = flags;
),
TP_printk("timer=%p function=%ps expires=%lu [timeout=%ld] cpu=%u idx=%u flags=%s",
__entry->timer, __entry->function, __entry->expires,
(long)__entry->expires - __entry->now,
__entry->flags & TIMER_CPUMASK,
__entry->flags >> TIMER_ARRAYSHIFT,
decode_timer_flags(__entry->flags & TIMER_TRACE_FLAGMASK))
);
/**
* 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, unsigned long baseclk),
TP_ARGS(timer, baseclk),
TP_STRUCT__entry(
__field( void *, timer )
__field( unsigned long, now )
__field( void *, function)
__field( unsigned long, baseclk )
),
TP_fast_assign(
__entry->timer = timer;
__entry->now = jiffies;
__entry->function = timer->function;
__entry->baseclk = baseclk;
),
TP_printk("timer=%p function=%ps now=%lu baseclk=%lu",
__entry->timer, __entry->function, __entry->now,
__entry->baseclk)
);
/**
* 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.
*/
DEFINE_EVENT(timer_class, timer_expire_exit,
TP_PROTO(struct timer_list *timer),
TP_ARGS(timer)
);
/**
* timer_cancel - called when the timer is canceled
* @timer: pointer to struct timer_list
*/
DEFINE_EVENT(timer_class, timer_cancel,
TP_PROTO(struct timer_list *timer),
TP_ARGS(timer)
);
#define decode_clockid(type) \
__print_symbolic(type, \
{ CLOCK_REALTIME, "CLOCK_REALTIME" }, \
{ CLOCK_MONOTONIC, "CLOCK_MONOTONIC" }, \
{ CLOCK_BOOTTIME, "CLOCK_BOOTTIME" }, \
{ CLOCK_TAI, "CLOCK_TAI" })
#define decode_hrtimer_mode(mode) \
__print_symbolic(mode, \
{ HRTIMER_MODE_ABS, "ABS" }, \
{ HRTIMER_MODE_REL, "REL" }, \
{ HRTIMER_MODE_ABS_PINNED, "ABS|PINNED" }, \
{ HRTIMER_MODE_REL_PINNED, "REL|PINNED" }, \
{ HRTIMER_MODE_ABS_SOFT, "ABS|SOFT" }, \
{ HRTIMER_MODE_REL_SOFT, "REL|SOFT" }, \
{ HRTIMER_MODE_ABS_PINNED_SOFT, "ABS|PINNED|SOFT" }, \
{ HRTIMER_MODE_REL_PINNED_SOFT, "REL|PINNED|SOFT" })
/**
* hrtimer_init - called when the hrtimer is initialized
* @hrtimer: pointer to struct hrtimer
* @clockid: the hrtimers clock
* @mode: the hrtimers mode
*/
TRACE_EVENT(hrtimer_init,
TP_PROTO(struct hrtimer *hrtimer, clockid_t clockid,
enum hrtimer_mode mode),
TP_ARGS(hrtimer, clockid, mode),
TP_STRUCT__entry(
__field( void *, hrtimer )
__field( clockid_t, clockid )
__field( enum hrtimer_mode, mode )
),
TP_fast_assign(
__entry->hrtimer = hrtimer;
__entry->clockid = clockid;
__entry->mode = mode;
),
TP_printk("hrtimer=%p clockid=%s mode=%s", __entry->hrtimer,
decode_clockid(__entry->clockid),
decode_hrtimer_mode(__entry->mode))
);
/**
* hrtimer_start - called when the hrtimer is started
* @hrtimer: pointer to struct hrtimer
*/
TRACE_EVENT(hrtimer_start,
TP_PROTO(struct hrtimer *hrtimer, enum hrtimer_mode mode),
TP_ARGS(hrtimer, mode),
TP_STRUCT__entry(
__field( void *, hrtimer )
__field( void *, function )
__field( s64, expires )
__field( s64, softexpires )
__field( enum hrtimer_mode, mode )
),
TP_fast_assign(
__entry->hrtimer = hrtimer;
__entry->function = hrtimer->function;
__entry->expires = hrtimer_get_expires(hrtimer);
__entry->softexpires = hrtimer_get_softexpires(hrtimer);
__entry->mode = mode;
),
TP_printk("hrtimer=%p function=%ps expires=%llu softexpires=%llu "
"mode=%s", __entry->hrtimer, __entry->function,
(unsigned long long) __entry->expires,
(unsigned long long) __entry->softexpires,
decode_hrtimer_mode(__entry->mode))
);
/**
* hrtimer_expire_entry - called immediately before the hrtimer callback
* @hrtimer: 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 *hrtimer, ktime_t *now),
TP_ARGS(hrtimer, now),
TP_STRUCT__entry(
__field( void *, hrtimer )
__field( s64, now )
__field( void *, function)
),
TP_fast_assign(
__entry->hrtimer = hrtimer;
__entry->now = *now;
__entry->function = hrtimer->function;
),
TP_printk("hrtimer=%p function=%ps now=%llu",
__entry->hrtimer, __entry->function,
(unsigned long long) __entry->now)
);
DECLARE_EVENT_CLASS(hrtimer_class,
TP_PROTO(struct hrtimer *hrtimer),
TP_ARGS(hrtimer),
TP_STRUCT__entry(
__field( void *, hrtimer )
),
TP_fast_assign(
__entry->hrtimer = hrtimer;
),
TP_printk("hrtimer=%p", __entry->hrtimer)
);
/**
* hrtimer_expire_exit - called immediately after the hrtimer callback returns
* @hrtimer: pointer to struct hrtimer
*
* When used in combination with the hrtimer_expire_entry tracepoint we can
* determine the runtime of the callback function.
*/
DEFINE_EVENT(hrtimer_class, hrtimer_expire_exit,
TP_PROTO(struct hrtimer *hrtimer),
TP_ARGS(hrtimer)
);
/**
* hrtimer_cancel - called when the hrtimer is canceled
* @hrtimer: pointer to struct hrtimer
*/
DEFINE_EVENT(hrtimer_class, hrtimer_cancel,
TP_PROTO(struct hrtimer *hrtimer),
TP_ARGS(hrtimer)
);
/**
* 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,
unsigned long long expires),
TP_ARGS(which, value, expires),
TP_STRUCT__entry(
__field( int, which )
__field( unsigned long long, 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=%llu it_value=%ld.%ld it_interval=%ld.%ld",
__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, unsigned long long now),
TP_ARGS(which, pid, now),
TP_STRUCT__entry(
__field( int , which )
__field( pid_t, pid )
__field( unsigned long long, now )
),
TP_fast_assign(
__entry->which = which;
__entry->now = now;
__entry->pid = pid_nr(pid);
),
TP_printk("which=%d pid=%d now=%llu", __entry->which,
(int) __entry->pid, __entry->now)
);
#ifdef CONFIG_NO_HZ_COMMON
#define TICK_DEP_NAMES \
tick_dep_mask_name(NONE) \
tick_dep_name(POSIX_TIMER) \
tick_dep_name(PERF_EVENTS) \
tick_dep_name(SCHED) \
tick_dep_name_end(CLOCK_UNSTABLE)
#undef tick_dep_name
#undef tick_dep_mask_name
#undef tick_dep_name_end
/* The MASK will convert to their bits and they need to be processed too */
#define tick_dep_name(sdep) TRACE_DEFINE_ENUM(TICK_DEP_BIT_##sdep); \
TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
#define tick_dep_name_end(sdep) TRACE_DEFINE_ENUM(TICK_DEP_BIT_##sdep); \
TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
/* NONE only has a mask defined for it */
#define tick_dep_mask_name(sdep) TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
TICK_DEP_NAMES
#undef tick_dep_name
#undef tick_dep_mask_name
#undef tick_dep_name_end
#define tick_dep_name(sdep) { TICK_DEP_MASK_##sdep, #sdep },
#define tick_dep_mask_name(sdep) { TICK_DEP_MASK_##sdep, #sdep },
#define tick_dep_name_end(sdep) { TICK_DEP_MASK_##sdep, #sdep }
#define show_tick_dep_name(val) \
__print_symbolic(val, TICK_DEP_NAMES)
TRACE_EVENT(tick_stop,
TP_PROTO(int success, int dependency),
TP_ARGS(success, dependency),
TP_STRUCT__entry(
__field( int , success )
__field( int , dependency )
),
TP_fast_assign(
__entry->success = success;
__entry->dependency = dependency;
),
TP_printk("success=%d dependency=%s", __entry->success, \
show_tick_dep_name(__entry->dependency))
);
#endif
#endif /* _TRACE_TIMER_H */
/* This part must be outside protection */
#include <trace/define_trace.h>