Archived
14
0
Fork 0
This repository has been archived on 2022-02-17. You can view files and clone it, but cannot push or open issues or pull requests.
linux-2.6/include/linux/irqflags.h
Steven Rostedt 6cd8a4bb2f ftrace: trace preempt off critical timings
Add preempt off timings. A lot of kernel core code is taken from the RT patch
latency trace that was written by Ingo Molnar.

This adds "preemptoff" and "preemptirqsoff" to /debugfs/tracing/available_tracers

Now instead of just tracing irqs off, preemption off can be selected
to be recorded.

When this is selected, it shares the same files as irqs off timings.
One can either trace preemption off, irqs off, or one or the other off.

By echoing "preemptoff" into /debugfs/tracing/current_tracer, recording
of preempt off only is performed. "irqsoff" will only record the time
irqs are disabled, but "preemptirqsoff" will take the total time irqs
or preemption are disabled. Runtime switching of these options is now
supported by simpling echoing in the appropriate trace name into
/debugfs/tracing/current_tracer.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:32:54 +02:00

106 lines
3.5 KiB
C

/*
* include/linux/irqflags.h
*
* IRQ flags tracing: follow the state of the hardirq and softirq flags and
* provide callbacks for transitions between ON and OFF states.
*
* This file gets included from lowlevel asm headers too, to provide
* wrapped versions of the local_irq_*() APIs, based on the
* raw_local_irq_*() macros from the lowlevel headers.
*/
#ifndef _LINUX_TRACE_IRQFLAGS_H
#define _LINUX_TRACE_IRQFLAGS_H
#ifdef CONFIG_TRACE_IRQFLAGS
extern void trace_softirqs_on(unsigned long ip);
extern void trace_softirqs_off(unsigned long ip);
extern void trace_hardirqs_on(void);
extern void trace_hardirqs_off(void);
# define trace_hardirq_context(p) ((p)->hardirq_context)
# define trace_softirq_context(p) ((p)->softirq_context)
# define trace_hardirqs_enabled(p) ((p)->hardirqs_enabled)
# define trace_softirqs_enabled(p) ((p)->softirqs_enabled)
# define trace_hardirq_enter() do { current->hardirq_context++; } while (0)
# define trace_hardirq_exit() do { current->hardirq_context--; } while (0)
# define trace_softirq_enter() do { current->softirq_context++; } while (0)
# define trace_softirq_exit() do { current->softirq_context--; } while (0)
# define INIT_TRACE_IRQFLAGS .softirqs_enabled = 1,
#else
# define trace_hardirqs_on() do { } while (0)
# define trace_hardirqs_off() do { } while (0)
# define trace_softirqs_on(ip) do { } while (0)
# define trace_softirqs_off(ip) do { } while (0)
# define trace_hardirq_context(p) 0
# define trace_softirq_context(p) 0
# define trace_hardirqs_enabled(p) 0
# define trace_softirqs_enabled(p) 0
# define trace_hardirq_enter() do { } while (0)
# define trace_hardirq_exit() do { } while (0)
# define trace_softirq_enter() do { } while (0)
# define trace_softirq_exit() do { } while (0)
# define INIT_TRACE_IRQFLAGS
#endif
#if defined(CONFIG_IRQSOFF_TRACER) || \
defined(CONFIG_PREEMPT_TRACER)
extern void stop_critical_timings(void);
extern void start_critical_timings(void);
#else
# define stop_critical_timings() do { } while (0)
# define start_critical_timings() do { } while (0)
#endif
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
#include <asm/irqflags.h>
#define local_irq_enable() \
do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0)
#define local_irq_disable() \
do { raw_local_irq_disable(); trace_hardirqs_off(); } while (0)
#define local_irq_save(flags) \
do { raw_local_irq_save(flags); trace_hardirqs_off(); } while (0)
#define local_irq_restore(flags) \
do { \
if (raw_irqs_disabled_flags(flags)) { \
raw_local_irq_restore(flags); \
trace_hardirqs_off(); \
} else { \
trace_hardirqs_on(); \
raw_local_irq_restore(flags); \
} \
} while (0)
#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
/*
* The local_irq_*() APIs are equal to the raw_local_irq*()
* if !TRACE_IRQFLAGS.
*/
# define raw_local_irq_disable() local_irq_disable()
# define raw_local_irq_enable() local_irq_enable()
# define raw_local_irq_save(flags) local_irq_save(flags)
# define raw_local_irq_restore(flags) local_irq_restore(flags)
#endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
#define safe_halt() \
do { \
trace_hardirqs_on(); \
raw_safe_halt(); \
} while (0)
#define local_save_flags(flags) raw_local_save_flags(flags)
#define irqs_disabled() \
({ \
unsigned long _flags; \
\
raw_local_save_flags(_flags); \
raw_irqs_disabled_flags(_flags); \
})
#define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
#endif /* CONFIG_X86 */
#endif