From nobody Wed Dec 17 18:59:50 2025 Received: from out-183.mta0.migadu.com (out-183.mta0.migadu.com [91.218.175.183]) (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 E62CA205516 for ; Sat, 15 Mar 2025 17:49:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.183 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742060993; cv=none; b=Ih7aG/qgua/J0dPdWZfqZDoXkpS3IC6Ft5YUxcFxzBKSKue4peN4SVP0+JkL6yVzusERZxLWvbSRq9oxS4ijnkUnkyFx6l5StXKuYKkmz0h4hXgHIqNDNUNleTVjYjNxa0QUSlSqMtOc4WUTyh1Tqh11iZ40fY9GYHlmoPktVIs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742060993; c=relaxed/simple; bh=0ftGgLW4/MlnZh9Fmz7q/GevfyJlJJyM4N09cbLOa4I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sx7B8pETvAxUYggL2D3ne7uE0W4ci/N33A1TShfb/6DCjTf4Ipxq4Oc1uZcVAsqTiAv8GZtFTLaN20aJe2ynuxTgELIMGsyuId2+cjcBKNIbi1et0NEk0qSPSluYq1fTWIZYSvHUbmCCdbnKN5a72Fe4WgFDW2+9TMPluoUDefc= 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=EsH21tpo; arc=none smtp.client-ip=91.218.175.183 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="EsH21tpo" 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=1742060990; 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=D9SGS5ZGVTJYUs7bi8rBcO4GG6XSRL+h8cbbja/hnd4=; b=EsH21tpoGivxemQBYrsxMd+ru7bHcE8LYPnGChI+hOtYbRl8sO0Czs0Q7Br3PmMb9k9bpa gce6M48m5W+CSQy02N7oSlHbmeiv0YDYjFi2vfK6zdqUHBTGYUDd4M1RiDkREBX83mGRH4 YD4a7IZYjimlw7tBXcpiVnolqcmcIyI= 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 3/9] memcg: introduce memcg_uncharge Date: Sat, 15 Mar 2025 10:49:24 -0700 Message-ID: <20250315174930.1769599-4-shakeel.butt@linux.dev> In-Reply-To: <20250315174930.1769599-1-shakeel.butt@linux.dev> References: <20250315174930.1769599-1-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" At multiple places in memcontrol.c, the memory and memsw page counters are being uncharged. This is error-prone. Let's move the functionality to a newly introduced memcg_uncharge and call it from all those places. Signed-off-by: Shakeel Butt Acked-by: Vlastimil Babka Reviewed-by: Roman Gushchin --- mm/memcontrol.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 28cb75b5bc66..b54e3a1d23bd 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1816,6 +1816,13 @@ static bool consume_stock(struct mem_cgroup *memcg, = unsigned int nr_pages, return ret; } =20 +static void memcg_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages) +{ + page_counter_uncharge(&memcg->memory, nr_pages); + if (do_memsw_account()) + page_counter_uncharge(&memcg->memsw, nr_pages); +} + /* * Returns stocks cached in percpu and reset cached information. */ @@ -1828,10 +1835,7 @@ static void drain_stock(struct memcg_stock_pcp *stoc= k) return; =20 if (stock_pages) { - page_counter_uncharge(&old->memory, stock_pages); - if (do_memsw_account()) - page_counter_uncharge(&old->memsw, stock_pages); - + memcg_uncharge(old, stock_pages); WRITE_ONCE(stock->nr_pages, 0); } =20 @@ -1893,9 +1897,7 @@ static void refill_stock(struct mem_cgroup *memcg, un= signed int nr_pages) * In case of unlikely failure to lock percpu stock_lock * uncharge memcg directly. */ - page_counter_uncharge(&memcg->memory, nr_pages); - if (do_memsw_account()) - page_counter_uncharge(&memcg->memsw, nr_pages); + memcg_uncharge(memcg, nr_pages); return; } __refill_stock(memcg, nr_pages); @@ -2855,12 +2857,8 @@ static struct obj_cgroup *drain_obj_stock(struct mem= cg_stock_pcp *stock) =20 mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); memcg1_account_kmem(memcg, -nr_pages); - if (!mem_cgroup_is_root(memcg)) { - page_counter_uncharge(&memcg->memory, nr_pages); - if (do_memsw_account()) - page_counter_uncharge(&memcg->memsw, - nr_pages); - } + if (!mem_cgroup_is_root(memcg)) + memcg_uncharge(memcg, nr_pages); =20 css_put(&memcg->css); } @@ -4689,9 +4687,7 @@ static inline void uncharge_gather_clear(struct uncha= rge_gather *ug) static void uncharge_batch(const struct uncharge_gather *ug) { if (ug->nr_memory) { - page_counter_uncharge(&ug->memcg->memory, ug->nr_memory); - if (do_memsw_account()) - page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory); + memcg_uncharge(ug->memcg, ug->nr_memory); if (ug->nr_kmem) { mod_memcg_state(ug->memcg, MEMCG_KMEM, -ug->nr_kmem); memcg1_account_kmem(ug->memcg, -ug->nr_kmem); --=20 2.47.1