From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=cmpxchg-org.20230601.gappssmtp.com header.i=@cmpxchg-org.20230601.gappssmtp.com header.b="t45yazmd" Received: from mail-qt1-x82a.google.com (mail-qt1-x82a.google.com [IPv6:2607:f8b0:4864:20::82a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DDDB7C9 for ; Wed, 29 Nov 2023 07:17:27 -0800 (PST) Received: by mail-qt1-x82a.google.com with SMTP id d75a77b69052e-41cc44736f2so37888881cf.3 for ; Wed, 29 Nov 2023 07:17:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20230601.gappssmtp.com; s=20230601; t=1701271047; x=1701875847; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=Ki5eAeZpOcI54YbTPSCFwp5UJ2eI9c3pK5uL2lEEtZM=; b=t45yazmdyT7D3V75tVpLMivlCMgeR/JvS/+C/lc7BHmzaprkmFWcankS3PQr7flX5U iro9DZmFQLFpz1giKu33Gx3a0hs2o5P0fXJ3nePPDmHNHJBITL4OvksYckJlpZuq6x/t KXpt4mDsz/Men8Xe0f6AnBNSr+ipGBke/yG6hy5keISNVDeIbmnlj0iDfO6k4wEV9XwL tO4AaMXr1vXUfpzmjVkE5JkVyr0ZdvPfDf38HIbti5rcMxqkXLJsocTDGnQU0Yl0KSu2 GyQmwozT25v4QB4gsFDL0PDXLh3atKDMZbJPIKzDVL5prK9VcM1yGRM4LnUwqvYt+3N0 wOAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701271047; x=1701875847; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=Ki5eAeZpOcI54YbTPSCFwp5UJ2eI9c3pK5uL2lEEtZM=; b=WADQSwjawZuF0owN/rMVK3QtMavMGavOgQJfgH+NqOyG5/uLvQ0KDgHHjKmisdwuOK kVjIPttEKEYqDd8uPzdTKiEpmRW1leLSFQAl/qmR/l2pJ2XqAhQV18JROzXcy1efTajs nQFVYcpjy5bBhMpx6f6M2jzmITG3Kcg9Y27PyMLp1s3ZP6/NCkG8PIm/z9MnEHTIZQRn WmvbZU3dCrflqLWH4QjwrnmSLRsOzn45izrFJJvmZkmo6iBkIungQjQCd64iyfeSCmKX nxeggxdsPg33gLDq8t56O8qDPo0QXyUEXyWoD8wZhT4DCr+KfsVWmHbD+Cx26Us5WlMX i10Q== X-Gm-Message-State: AOJu0YyLA0tfwLcLXRUhzesYZAwLsLhzfDYfGX1MyMAo9vCV3DAyTTnh KoGNfvDNwX33s5HdyfwS5qIwJw== X-Google-Smtp-Source: AGHT+IEZIE1AM5E8zn+REarKZMAnlku7irhSBH7MhlpFKWn2MeAvwTjAn78X+XkDrH28XBpWMoOlEQ== X-Received: by 2002:ac8:7d12:0:b0:423:792f:d5ca with SMTP id g18-20020ac87d12000000b00423792fd5camr24998108qtb.63.1701271046994; Wed, 29 Nov 2023 07:17:26 -0800 (PST) Received: from localhost (2603-7000-0c01-2716-da5e-d3ff-fee7-26e7.res6.spectrum.com. [2603:7000:c01:2716:da5e:d3ff:fee7:26e7]) by smtp.gmail.com with ESMTPSA id ay30-20020a05622a229e00b00423a0d10d4csm4386593qtb.62.2023.11.29.07.17.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Nov 2023 07:17:26 -0800 (PST) Date: Wed, 29 Nov 2023 10:17:21 -0500 From: Johannes Weiner To: Nhat Pham Cc: akpm@linux-foundation.org, cerasuolodomenico@gmail.com, yosryahmed@google.com, sjenning@redhat.com, ddstreet@ieee.org, vitaly.wool@konsulko.com, mhocko@kernel.org, roman.gushchin@linux.dev, shakeelb@google.com, muchun.song@linux.dev, chrisl@kernel.org, linux-mm@kvack.org, kernel-team@meta.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, shuah@kernel.org Subject: Re: [PATCH v7 3/6] zswap: make shrinking memcg-aware Message-ID: <20231129151721.GC135852@cmpxchg.org> References: <20231127234600.2971029-1-nphamcs@gmail.com> <20231127234600.2971029-4-nphamcs@gmail.com> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231127234600.2971029-4-nphamcs@gmail.com> On Mon, Nov 27, 2023 at 03:45:57PM -0800, Nhat Pham wrote: > static void shrink_worker(struct work_struct *w) > { > struct zswap_pool *pool = container_of(w, typeof(*pool), > shrink_work); > + struct mem_cgroup *memcg; > int ret, failures = 0; > > + /* global reclaim will select cgroup in a round-robin fashion. */ > do { > - ret = zswap_reclaim_entry(pool); > - if (ret) { > - zswap_reject_reclaim_fail++; > - if (ret != -EAGAIN) > - break; > + spin_lock(&zswap_pools_lock); > + memcg = pool->next_shrink = > + mem_cgroup_iter_online(NULL, pool->next_shrink, NULL, true); > + > + /* full round trip */ > + if (!memcg) { > + spin_unlock(&zswap_pools_lock); > if (++failures == MAX_RECLAIM_RETRIES) > break; > + > + goto resched; > } > + > + /* > + * Acquire an extra reference to the iterated memcg in case the > + * original reference is dropped by the zswap offlining callback. > + */ > + css_get(&memcg->css); struct mem_cgroup isn't defined when !CONFIG_MEMCG. This needs a mem_cgroup_get() wrapper and a dummy function for no-memcg builds. With that fixed, though, everything else looks good to me: Acked-by: Johannes Weiner