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From:   Peter Zijlstra <peterz@infradead.org>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Yu Zhao <yuzhao@google.com>, Stephen Rothwell <sfr@rothwell.id.au>,
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Subject: Re: [PATCH v10 08/14] mm: multi-gen LRU: support page table walks
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References: <20220407031525.2368067-1-yuzhao@google.com>
 <20220407031525.2368067-9-yuzhao@google.com>
 <20220411191621.0378467ad99ebc822d5ad005@linux-foundation.org>
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On Mon, Apr 11, 2022 at 07:16:21PM -0700, Andrew Morton wrote:
> On Wed,  6 Apr 2022 21:15:20 -0600 Yu Zhao <yuzhao@google.com> wrote:

> > +#ifdef CONFIG_LRU_GEN
> > +static void mem_cgroup_attach(struct cgroup_taskset *tset)
> > +{
> > +	struct cgroup_subsys_state *css;
> > +	struct task_struct *task = NULL;
> > +
> > +	cgroup_taskset_for_each_leader(task, css, tset)
> > +		break;
> 
> Does this actually do anything?

Yeah, it finds the first leader if there is any, but this is indeed
quite terrible coding style.