From nobody Sat Oct 11 04:11:30 2025 Received: from out-172.mta1.migadu.com (out-172.mta1.migadu.com [95.215.58.172]) (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 4649C1B043E for ; Thu, 12 Jun 2025 08:28:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749716912; cv=none; b=A7p/JMUcsCMELCwrPmYy3XjS+/viYNOakWvE4x0GqW+K/1uEbw9pg0bJ8PQQzIvwkovKbuhFEUlRPANwN45JVYMkj5vXhMh6yvYyrm4EQc0RUSGgsgYQx/i86YNumei8GdFypRy+/vKGGVJN8IuDulLenJOy4fwgdJjH6audKJU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749716912; c=relaxed/simple; bh=w5lvnxdf7nXQzABIUueKfM2G7ZWWXlgNS18Oez8SQuk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=k5bB5/9U4k2M06T2738/6Fo77lOPZHMXHTRD+0wFTQeQenzKFubmhbnwwxD3jPxdLoG48ElA8wRpWO4Rg502i3VgXCf17tZbC0ysaPwzSKYjinhXTVH0NLgdgU/z+SWjVyEwr3eTQZ1VtqMIi8bgrCZG5kas4uqiLt98T3rTkqs= 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=K/ia8tsa; arc=none smtp.client-ip=95.215.58.172 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="K/ia8tsa" 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=1749716909; 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=FK5GViGeaS0eKXb1CGklOs8Lcazv9ig1sTbfs/WnUDs=; b=K/ia8tsaN5YSVwzcZ7cSw6MtYYEdAZL9pCWwtEBdCG53ZTxJTtSEirziliq4lO65RcDcXH cWaXE6uKdHS0P0oc/dpDtfPnvsIIDISGN9MtmFylu+E8VSo1FfDvr5PMJUe8vnBkAhTP9c WNWZV4ihnhgxf5TOOu61Q2VzdSWRVoE= From: Hao Ge To: Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , Mike Rapoport , Richard Henderson , Matt Turner , Dennis Zhou , Tejun Heo , Christoph Lameter , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Kent Overstreet Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, linux-s390@vger.kernel.org, Hao Ge , Hao Ge Subject: [PATCH 5/5] mm/alloc_tag: add the CONFIG_ARCH_NEEDS_WEAK_PER_CPU macro when statically defining the percpu variable _shared_alloc_tag Date: Thu, 12 Jun 2025 16:27:30 +0800 Message-Id: In-Reply-To: References: 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" From: Hao Ge Recently discovered this entry while checking kallsyms on ARM64: ffff800083e509c0 D _shared_alloc_tag If CONFIG_ARCH_NEEDS_WEAK_PER_CPU is not defined(it is only defined for s390 and alpha architectures),there's no need to statically define the percpu variable _shared_alloc_tag. As the number of CPUs increases,the wasted memory will grow correspondingly. Enclose the definition of _shared_alloc_tag within the CONFIG_ARCH_NEEDS_WEAK_PER_CPU condition. Suggested-by: Suren Baghdasaryan Signed-off-by: Hao Ge --- lib/alloc_tag.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c index c7f602fa7b23..14fd66f26e42 100644 --- a/lib/alloc_tag.c +++ b/lib/alloc_tag.c @@ -24,8 +24,10 @@ static bool mem_profiling_support; =20 static struct codetag_type *alloc_tag_cttype; =20 +#ifdef CONFIG_ARCH_NEEDS_WEAK_PER_CPU DEFINE_PER_CPU(struct alloc_tag_counters, _shared_alloc_tag); EXPORT_SYMBOL(_shared_alloc_tag); +#endif =20 DEFINE_STATIC_KEY_MAYBE(CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT, mem_alloc_profiling_key); --=20 2.25.1