Re: [patch 9/9] x86, bts, ftrace: a BTS ftrace plug-in prototype

[Andi Kleen <andi@firstfloor.org>]

Markus Metzger <markus.t.metzger@intel.com> writes:

Basic idea looks very useful. Thanks.

> +static void bts_trace_cpuinit(struct cpuinfo_x86 *c)

That should be somewhere generic I think. Doesn't ptrace have it too?

-Andi


> +{
> +	switch (c->x86) {
> +	case 0x6:
> +		switch (c->x86_model) {
> +		case 0x0 ... 0xC:
> +			break;
> +		case 0xD:
> +		case 0xE: /* Pentium M */
> +			sizeof_field = sizeof(long);
> +			debugctl_mask = (1<<6)|(1<<7);
> +			break;
> +		default:
> +			sizeof_field = 8;
> +			debugctl_mask = (1<<6)|(1<<7);
> +			break;
> +		}
> +		break;
> +	case 0xF:
> +		switch (c->x86_model) {
> +		case 0x0:
> +		case 0x1:
> +		case 0x2: /* Netburst */
> +			sizeof_field = sizeof(long);
> +			debugctl_mask = (1<<2)|(1<<3);
> +			break;
> +		default:
> +			/* sorry, don't know about them */
> +			break;
> +		}
> +		break;
> +	default:
> +		/* sorry, don't know about them */
> +		break;
> +	}
> +}
> +
> +static inline void bts_enable(void)
> +{
> +	unsigned long debugctl;
> +
> +	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);
> +	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl | debugctl_mask);
> +}
> +
> +static inline void bts_disable(void)
> +{
> +	unsigned long debugctl;
> +
> +	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);
> +	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl & ~debugctl_mask);
> +}
> +
> +static void bts_trace_reset(struct trace_array *tr)
> +{
> +	int cpu;
> +
> +	tr->time_start = ftrace_now(tr->cpu);
> +

-- 
ak@linux.intel.com