From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philippe Longepe Subject: [PATCH V6 2/4] intel_pstate: Optimize calculation for max/min_perf_adj Date: Tue, 8 Mar 2016 10:31:17 +0100 Message-ID: <1457429481-13283-6-git-send-email-philippe.longepe@linux.intel.com> References: <1457429481-13283-1-git-send-email-philippe.longepe@linux.intel.com> Return-path: Received: from mga01.intel.com ([192.55.52.88]:43546 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932227AbcCHJaS (ORCPT ); Tue, 8 Mar 2016 04:30:18 -0500 In-Reply-To: <1457429481-13283-1-git-send-email-philippe.longepe@linux.intel.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: linux-pm@vger.kernel.org Cc: srinivas.pandruvada@linux.intel.com, rafael@kernel.org 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 --- drivers/cpufreq/intel_pstate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 114e4e0..c46d23a 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -828,11 +828,11 @@ 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); } -- 1.9.1