Re: [PATCH v4 1/4] Produce system time from correlated clocksource
From: Richard Cochran
Date: Tue Oct 13 2015 - 01:26:33 EST
On Mon, Oct 12, 2015 at 11:45:19AM -0700, Christopher S. Hall wrote:
> +int get_correlated_timestamp(struct correlated_ts *crt,
> + struct correlated_cs *crs)
> +{
> + struct timekeeper *tk = &tk_core.timekeeper;
> + unsigned long seq;
> + cycles_t cycles, cycles_now, cycles_last;
> + ktime_t base;
> + s64 nsecs;
> + int ret;
> +
> + do {
> + seq = read_seqcount_begin(&tk_core.seq);
> + /*
> + * Verify that the correlated clocksoure is related to
> + * the currently installed timekeeper clocksoure
> + */
> + if (tk->tkr_mono.clock != crs->related_cs)
> + return -ENODEV;
> +
> + /*
> + * Get a timestamp from the device if get_ts is non-NULL
> + */
> + if( crt->get_ts ) {
CodingStyle.
> + ret = crt->get_ts(crt);
> + if (ret)
> + return ret;
> + }
> +
> + /*
> + * Convert the timestamp to timekeeper clock cycles
> + */
> + cycles = crs->convert(crs, crt->system_ts);
> +
> + /*
> + * If we have get_ts is valid, we know the cycles value
> + * value is up to date and we can just do the conversion
> + */
> + if( crt->get_ts )
Ditto.
> + goto do_convert;
> +
Thanks,
Richard
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