From patchwork Mon Apr 15 09:48:21 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dawei Li X-Patchwork-Id: 789146 Received: from smtpbgeu2.qq.com (smtpbgeu2.qq.com [18.194.254.142]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8888059178; Mon, 15 Apr 2024 09:48:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=18.194.254.142 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713174539; cv=none; b=h1SDrksle7+Q+KCxG++z5V6ZLi54xjsbwkPpzAZvcNwcYPA5DW0yuBkD3iBQIhtI1li8Wgzez+S51fccJIoipZYDCgZ8afN+l+dkJIO8y/QPAtFPtN7Kt/gH7tSiU3Qsrai3hq+sJ/T6jD0SzON+2kNjhilh244I3AY/k+LW/No= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713174539; c=relaxed/simple; bh=B1hg7pDwSLKfgIcaXOtyaNyjw7ZjJf4j7FTIwgWeOBI=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=VmiaPAmpanpgNa8KbKv79lPUlYbHzspzKrxxtGQfVCyZGjxJlUzAy79A25A7B1Lt14HE23wiEyell+7XNNlNXLQwF7mIPm1u+Zc3WcErJr4Ow3Mly2aE7qDL95woC3FhN5GyHmebNxgyR3p5YAEruwP2gDEDQZOGG5DSjmjyeMw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=shingroup.cn; spf=pass smtp.mailfrom=shingroup.cn; arc=none smtp.client-ip=18.194.254.142 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=shingroup.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=shingroup.cn X-QQ-mid: bizesmtp91t1713174505tqb1fvlq X-QQ-Originating-IP: Mg2qhqrNmZ4DabM2cVzkXEFBLfsGGq0/bsCi8GmCGA8= Received: from localhost ( [112.0.147.129]) by bizesmtp.qq.com (ESMTP) with id ; Mon, 15 Apr 2024 17:48:23 +0800 (CST) X-QQ-SSF: 01400000000000903000000A0000000 X-QQ-FEAT: 5EQLibG9+Dhd65WhHLcwzoaQdGDyW3R0enkqqtQ1Ltc3ObGMGL+5hVXPVJCU/ YqkAQCvRovbfEeki8TEO1E84nUhnEEPW724dbC47yzz+rP9NhpeZVlcpFVx10rzybAT2No/ LIJY7OZxPUnEsS7ufuy1Kk2CA6RxuKQDFK+4lq45tvBvd00qAamsXDx6LPzLz5awqyPPcpK YQbycxYKmcMzCMAJEYeQ1IEO7hjhqjdCBIR+vOb+mMV/Z8D3lklHLISOqGv3O1wgt74lkKr A11CELi1hyoVzot4n5jQSeq5+vStcEmqHIY+23YcJpidqCn4jkLrz9X5NmbY0WSUN3dwrdv MvSvVywWBAbNEjvsgeUOUiKkDWY5Fa5WbHydfPBZGRCnaA0PFLJEU3lkRVYc3e8O+oQhhNY X-QQ-GoodBg: 2 X-BIZMAIL-ID: 5948653929054549873 From: Dawei Li To: daniel.lezcano@kernel.org, rafael@kernel.org Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Dawei Li Subject: [PATCH] powercap: Avoid explicit cpumask allocation on stack Date: Mon, 15 Apr 2024 17:48:21 +0800 Message-Id: <20240415094821.3060892-1-dawei.li@shingroup.cn> X-Mailer: git-send-email 2.27.0 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:shingroup.cn:qybglogicsvrgz:qybglogicsvrgz5a-1 In general it's preferable to avoid placing cpumasks on the stack, as for large values of NR_CPUS these can consume significant amounts of stack space and make stack overflows more likely. Use cpumask_weight_and() to avoid the need for a temporary cpumask on the stack. Signed-off-by: Dawei Li --- drivers/powercap/dtpm_cpu.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c index bc90126f1b5f..6b6f51b21550 100644 --- a/drivers/powercap/dtpm_cpu.c +++ b/drivers/powercap/dtpm_cpu.c @@ -43,13 +43,11 @@ static u64 set_pd_power_limit(struct dtpm *dtpm, u64 power_limit) struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); struct em_perf_domain *pd = em_cpu_get(dtpm_cpu->cpu); struct em_perf_state *table; - struct cpumask cpus; unsigned long freq; u64 power; int i, nr_cpus; - cpumask_and(&cpus, cpu_online_mask, to_cpumask(pd->cpus)); - nr_cpus = cpumask_weight(&cpus); + nr_cpus = cpumask_weight_and(cpu_online_mask, to_cpumask(pd->cpus)); rcu_read_lock(); table = em_perf_state_from_pd(pd); @@ -123,11 +121,9 @@ static int update_pd_power_uw(struct dtpm *dtpm) struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); struct em_perf_domain *em = em_cpu_get(dtpm_cpu->cpu); struct em_perf_state *table; - struct cpumask cpus; int nr_cpus; - cpumask_and(&cpus, cpu_online_mask, to_cpumask(em->cpus)); - nr_cpus = cpumask_weight(&cpus); + nr_cpus = cpumask_weight_and(cpu_online_mask, to_cpumask(em->cpus)); rcu_read_lock(); table = em_perf_state_from_pd(em);