Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752020AbbECJAh (ORCPT ); Sun, 3 May 2015 05:00:37 -0400 Received: from www.osadl.org ([62.245.132.105]:59115 "EHLO www.osadl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751598AbbECJA2 (ORCPT ); Sun, 3 May 2015 05:00:28 -0400 From: Nicholas Mc Guire To: Ingo Molnar Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, Nicholas Mc Guire Subject: [PATCH] sched/core: remove unnecessary down/up conversion Date: Sun, 3 May 2015 10:51:56 +0200 Message-Id: <1430643116-24049-1-git-send-email-hofrat@osadl.org> X-Mailer: git-send-email 1.7.10.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2123 Lines: 63 rt_period_us is automatically type converted from u64 to long and then cast back to u64 - this down/up conversion is unnecessary and can be removed to improve readability. Signed-off-by: Nicholas Mc Guire --- sched_group_set_rt_period is called in one place at kernel/sched/core.c:cpu_rt_period_write_uint:8318 static int cpu_rt_period_write_uint(struct cgroup_subsys_state *css, struct cftype *cftype, u64 rt_period_us) { return sched_group_set_rt_period(css_tg(css), rt_period_us); } here rt_period_us is automatically type converted to long and then cast back to u64 in sched_group_set_rt_period which should be equivalent to simply passing it as u64 and dropping the cast. static int sched_group_set_rt_period(struct task_group *tg, long rt_period_us) { u64 rt_runtime, rt_period; rt_period = (u64)rt_period_us * NSEC_PER_USEC; rt_runtime = tg->rt_bandwidth.rt_runtime; return tg_set_rt_bandwidth(tg, rt_period, rt_runtime); } Patch was compile tested for x86_64_defconfig Patch is against 4.1-rc1 (localversion-next is -next-20150501) kernel/sched/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fe22f75..cf7f327 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7739,11 +7739,11 @@ static long sched_group_rt_runtime(struct task_group *tg) return rt_runtime_us; } -static int sched_group_set_rt_period(struct task_group *tg, long rt_period_us) +static int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us) { u64 rt_runtime, rt_period; - rt_period = (u64)rt_period_us * NSEC_PER_USEC; + rt_period = rt_period_us * NSEC_PER_USEC; rt_runtime = tg->rt_bandwidth.rt_runtime; return tg_set_rt_bandwidth(tg, rt_period, rt_runtime); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/