From nobody Wed Dec 17 19:00:27 2025 Received: from out-187.mta1.migadu.com (out-187.mta1.migadu.com [95.215.58.187]) (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 A6C701CD3F for ; Fri, 4 Apr 2025 01:39:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.187 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743730777; cv=none; b=ERGUIHp8Eu8KAPm2DWGnHujSWz5JafoptwcqONy4PIGMEfoySmAANEkOsjo8t3gLxcR5O6bKm07YTl1mAYESi9MwStxDi9WcE5/4x9Ob/Vi0Xh5ji2ypMCJo1uZsqHP5318MbNZgCjW5uL+iWz8zntBT3F8YIFt++nygPCie89w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743730777; c=relaxed/simple; bh=Wt9frfyEWA8VJjXPXQvYvV1auqH17c8eWrrofBDNj+w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bsnsbbvPyIXrXZ/8OF6zYUPD/TyARXMaI0yfKd/8w5v/hhBtHU9t1IlHcptCIKMrLvMlF6YXr73kq+Ut/zTMmZqc6drrui0FAOLN0qkYc14MuOs309GG6HeSfxqogTGbQ4WXUiBXoiMrKAoTSM2Kg0NNWimf037B5TTVR3IsB1c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Gtp/lT7A; arc=none smtp.client-ip=95.215.58.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Gtp/lT7A" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1743730773; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Umv4btRy/nEoNx2OIY9ZLc4o2g+KibZrAp3iooZEy6Y=; b=Gtp/lT7ARKgjwmrfUuMxwEW+dvted/jx4y+oaBXV12gQbAtjbE8JtTP3C+4yGfOpV4rVeI zGYBza0gUb2vsRxmh6rV2dHte5ZmqbcQmI0Clp8KzTFduq0UEOnqRA/K9SlVURO2f6fy75 aLWZys/FK/LwV7mCWlcNJVI/EbRZjuk= From: Shakeel Butt To: Andrew Morton Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Muchun Song , Vlastimil Babka , Sebastian Andrzej Siewior , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Meta kernel team Subject: [PATCH v2 1/9] memcg: remove root memcg check from refill_stock Date: Thu, 3 Apr 2025 18:39:05 -0700 Message-ID: <20250404013913.1663035-2-shakeel.butt@linux.dev> In-Reply-To: <20250404013913.1663035-1-shakeel.butt@linux.dev> References: <20250404013913.1663035-1-shakeel.butt@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" refill_stock can not be called with root memcg, so there is no need to check it. Instead add a warning if root is ever passed to it. Reviewed-by: Roman Gushchin Acked-by: Vlastimil Babka Signed-off-by: Shakeel Butt --- mm/memcontrol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index b16b5b807d7c..ae1e953cead7 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1893,13 +1893,13 @@ static void refill_stock(struct mem_cgroup *memcg, = unsigned int nr_pages) { unsigned long flags; =20 + VM_WARN_ON_ONCE(mem_cgroup_is_root(memcg)); + if (!local_trylock_irqsave(&memcg_stock.stock_lock, flags)) { /* * In case of unlikely failure to lock percpu stock_lock * uncharge memcg directly. */ - if (mem_cgroup_is_root(memcg)) - return; page_counter_uncharge(&memcg->memory, nr_pages); if (do_memsw_account()) page_counter_uncharge(&memcg->memsw, nr_pages); --=20 2.47.1