From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hao Lee Subject: Re: [PATCH] cgroup: Delete unnecessary if statement in css_visible() Date: Thu, 1 Oct 2020 14:44:26 +0000 Message-ID: <20201001144426.GA8928@haolee.github.io> References: <20200829100202.GA855@haolee.github.io> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=zMEk1N3CPCYeqn3NdVc8YKuWmziT/BdSn/3LxjNiWOU=; b=oQQBAehJs1Sn1ReuyfeqJbYvwoxoA8y+v5MEwvM2JIUhO3ln3XX1m/RkxitRT5Va+O NZOZMTBf53KxgTUUu7JauIBYEOLXSyOmljXm2VWWePOfOdDpVQbwfGHXaN9fOAQCSq7A j1M0/gcMDuIbO/QiA6piA4mrs5YbNaVagVsf9TSbFahelXCeQnyoZr/CEvh521IVNTWz rNkogept4EfC35lmArB9frWAs8+81EqlPoW+c8wgaw3ey9v8EqB86AM4M/fH0rSIDHQF aNW79D0G9oiJTuXKtcNjugOVD5gY5PsyO76bZq2IXoGF+w22aa3auu9JsAZj+RC3nV9+ u73Q== Content-Disposition: inline In-Reply-To: <20200829100202.GA855-aLGwGs2JoHKXlosIQRE7iA@public.gmane.org> List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org Cc: lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Hi, ping... On Sat, Aug 29, 2020 at 10:03:16AM +0000, Hao Lee wrote: > css_visible() is called in either cgroup_apply_control_enable() > or cgroup_apply_control_disable(). > In cgroup_apply_control_enable(), we have checked ss_mask before calling > css_visible(), so there is no need to do the same thing again. > In cgroup_apply_control_disable(): > - If css->parent is not NULL, we have checked ss_mask in the > second condition, so there is no need to do the same thing again. > - If css->parent is NULL, dsct is root cgroup so the deleted if > statement is always false and there is no need to keep it. > > Signed-off-by: Hao Lee > --- > kernel/cgroup/cgroup.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c > index dd247747ec14..b6714166106d 100644 > --- a/kernel/cgroup/cgroup.c > +++ b/kernel/cgroup/cgroup.c > @@ -3023,8 +3023,6 @@ static bool css_visible(struct cgroup_subsys_state *css) > > if (cgroup_control(cgrp) & (1 << ss->id)) > return true; > - if (!(cgroup_ss_mask(cgrp) & (1 << ss->id))) > - return false; > return cgroup_on_dfl(cgrp) && ss->implicit_on_dfl; > } > > -- > 2.24.1 >