linux/arch/sparc/include/asm/perf_event.h
Peter Zijlstra e360adbe29 irq_work: Add generic hardirq context callbacks
Provide a mechanism that allows running code in IRQ context. It is
most useful for NMI code that needs to interact with the rest of the
system -- like wakeup a task to drain buffers.

Perf currently has such a mechanism, so extract that and provide it as
a generic feature, independent of perf so that others may also
benefit.

The IRQ context callback is generated through self-IPIs where
possible, or on architectures like powerpc the decrementer (the
built-in timer facility) is set to generate an interrupt immediately.

Architectures that don't have anything like this get to do with a
callback from the timer tick. These architectures can call
irq_work_run() at the tail of any IRQ handlers that might enqueue such
work (like the perf IRQ handler) to avoid undue latencies in
processing the work.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[ various fixes ]
Signed-off-by: Huang Ying <ying.huang@intel.com>
LKML-Reference: <1287036094.7768.291.camel@yhuang-dev>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-18 19:58:50 +02:00

34 lines
858 B
C

#ifndef __ASM_SPARC_PERF_EVENT_H
#define __ASM_SPARC_PERF_EVENT_H
#ifdef CONFIG_PERF_EVENTS
#include <asm/ptrace.h>
extern void init_hw_perf_events(void);
#define perf_arch_fetch_caller_regs(regs, ip) \
do { \
unsigned long _pstate, _asi, _pil, _i7, _fp; \
__asm__ __volatile__("rdpr %%pstate, %0\n\t" \
"rd %%asi, %1\n\t" \
"rdpr %%pil, %2\n\t" \
"mov %%i7, %3\n\t" \
"mov %%i6, %4\n\t" \
: "=r" (_pstate), \
"=r" (_asi), \
"=r" (_pil), \
"=r" (_i7), \
"=r" (_fp)); \
(regs)->tstate = (_pstate << 8) | \
(_asi << 24) | (_pil << 20); \
(regs)->tpc = (ip); \
(regs)->tnpc = (regs)->tpc + 4; \
(regs)->u_regs[UREG_I6] = _fp; \
(regs)->u_regs[UREG_I7] = _i7; \
} while (0)
#else
static inline void init_hw_perf_events(void) { }
#endif
#endif