advisor_ctx
static struct advisor_ctx advisor_ctx;
advisor_ctx = (const struct advisor_ctx){ 0 };
advisor_ctx.start_scan = ktime_get();
static inline unsigned long prev_scan_time(struct advisor_ctx *ctx,
scan_time = div_s64(ktime_ms_delta(ktime_get(), advisor_ctx.start_scan),
cpu_time_diff = cpu_time - advisor_ctx.cpu_time;
last_scan_time = prev_scan_time(&advisor_ctx, scan_time);
change = ewma(advisor_ctx.change, change);
advisor_ctx.change = change;
advisor_ctx.scan_time = scan_time;
advisor_ctx.cpu_time = cpu_time;