From 6795b85c6a4f690e61e7be31aa150d945c723fb5 Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Mon, 26 Oct 2009 18:49:14 +0000 Subject: powerpc: tracing: Add powerpc tracepoints for timer entry and exit We can monitor the effectiveness of our power management of both the kernel and hypervisor by probing the timer interrupt. For example, on this box we see 10.37s timer interrupts on an idle core: -0 [010] 3900.671297: timer_interrupt_entry: pt_regs=c0000000ce1e7b10 -0 [010] 3900.671302: timer_interrupt_exit: pt_regs=c0000000ce1e7b10 -0 [010] 3911.042963: timer_interrupt_entry: pt_regs=c0000000ce1e7b10 -0 [010] 3911.042968: timer_interrupt_exit: pt_regs=c0000000ce1e7b10 -0 [010] 3921.414630: timer_interrupt_entry: pt_regs=c0000000ce1e7b10 -0 [010] 3921.414635: timer_interrupt_exit: pt_regs=c0000000ce1e7b10 Since we have a 207MHz decrementer it will go negative and fire every 10.37s even if Linux is completely idle. Signed-off-by: Anton Blanchard Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/trace.h | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/trace.h b/arch/powerpc/include/asm/trace.h index 187696da5ae..b558c31d409 100644 --- a/arch/powerpc/include/asm/trace.h +++ b/arch/powerpc/include/asm/trace.h @@ -42,6 +42,40 @@ TRACE_EVENT(irq_exit, TP_printk("pt_regs=%p", __entry->regs) ); +TRACE_EVENT(timer_interrupt_entry, + + TP_PROTO(struct pt_regs *regs), + + TP_ARGS(regs), + + TP_STRUCT__entry( + __field(struct pt_regs *, regs) + ), + + TP_fast_assign( + __entry->regs = regs; + ), + + TP_printk("pt_regs=%p", __entry->regs) +); + +TRACE_EVENT(timer_interrupt_exit, + + TP_PROTO(struct pt_regs *regs), + + TP_ARGS(regs), + + TP_STRUCT__entry( + __field(struct pt_regs *, regs) + ), + + TP_fast_assign( + __entry->regs = regs; + ), + + TP_printk("pt_regs=%p", __entry->regs) +); + #endif /* _TRACE_POWERPC_H */ #undef TRACE_INCLUDE_PATH -- cgit v1.2.3-70-g09d2