Re: [PATCH 08/10] clocksource/drivers/hyper-v: Handle sched_clock differences inline

From: Wei Liu
Date: Mon Feb 01 2021 - 13:56:22 EST


On Wed, Jan 27, 2021 at 12:23:43PM -0800, Michael Kelley wrote:
[...]
> +/*
> + * Reference to pv_ops must be inline so objtool
> + * detection of noinstr violations can work correctly.
> + */
> +static __always_inline void hv_setup_sched_clock(void *sched_clock)

sched_clock_register is not trivial. Having __always_inline here is
going to make the compiled object bloated.

Given this is a static function, I don't think we need to specify any
inline keyword. The compiler should be able to determine whether this
function should be inlined all by itself.

Wei.

> +{
> +#ifdef CONFIG_GENERIC_SCHED_CLOCK
> + /*
> + * We're on an architecture with generic sched clock (not x86/x64).
> + * The Hyper-V sched clock read function returns nanoseconds, not
> + * the normal 100ns units of the Hyper-V synthetic clock.
> + */
> + sched_clock_register(sched_clock, 64, NSEC_PER_SEC);
> +#else
> +#ifdef CONFIG_PARAVIRT
> + /* We're on x86/x64 *and* using PV ops */
> + pv_ops.time.sched_clock = sched_clock;
> +#endif
> +#endif
> +}
> +
> static bool __init hv_init_tsc_clocksource(void)
> {
> u64 tsc_msr;
> --
> 1.8.3.1
>