From a158bed5dc92bd83338225135d448958e0b3745d Mon Sep 17 00:00:00 2001 From: Philippe Longepe Date: Sun, 6 Mar 2016 08:34:04 +0100 Subject: intel_pstate: Optimize calculation for max/min_perf_adj mul_fp(int_tofp(A), B) expands to: ((A << FRAC_BITS) * B) >> FRAC_BITS, so the same result can be obtained via simple multiplication A * B. Apply this observation to max_perf * limits->max_perf and max_perf * limits->min_perf in intel_pstate_get_min_max()." Signed-off-by: Philippe Longepe Acked-by: Srinivas Pandruvada Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/cpufreq') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 864214de5cdf..5b5bfc1c90f1 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -831,11 +831,11 @@ static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max) * policy, or by cpu specific default values determined through * experimentation. */ - max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits->max_perf)); + max_perf_adj = fp_toint(max_perf * limits->max_perf); *max = clamp_t(int, max_perf_adj, cpu->pstate.min_pstate, cpu->pstate.turbo_pstate); - min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits->min_perf)); + min_perf = fp_toint(max_perf * limits->min_perf); *min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf); } -- cgit v1.2.3