From nobody Fri Oct 10 21:10:20 2025 Received: from out-170.mta1.migadu.com (out-170.mta1.migadu.com [95.215.58.170]) (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 2D6A6248883; Fri, 13 Jun 2025 03:06:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.170 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749783990; cv=none; b=ndO80KWtQPoRIRaxB9A3A03jJcF41Uz/ATbTZUdwAuCuRe2x33+5vZwxoxCrhieF49lUWM3+CQVDd9f2EFgQen18ry00Ro00jzAUvvbte1mA/t5gaGsnVuPdeFUenhE02iI4cRFpAwND2E3JJlFJoOtH5abGLYjbG/wxpDImMwc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749783990; c=relaxed/simple; bh=w5lvnxdf7nXQzABIUueKfM2G7ZWWXlgNS18Oez8SQuk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=r3Ci+t7iGp4dOibm3EUSZx1xZjCDUPGelozPYei31Ug3FTNNQBHhqiurdQNGyfSuIgkeuU7fj0hanJLmbQw3j+oeN0KO8DAP1I22A4vUJKMLM7s9wJ/HdcC96FsSEoYRMIrKdxRHXEMFmaAsPzLQxU+DeieKqaYRIff7fya4tyc= 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=VmrD+p0k; arc=none smtp.client-ip=95.215.58.170 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="VmrD+p0k" 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=1749783986; 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=VmrD+p0k1+hGglgFMyD3kLFYXh+SMTmVlSrsl5nL5sfKCHcBwrkI++kzMSRi0v0hWA09jU Awtwc4OjwwnWnH73KWQTYi0o6jxXhNdzlAKgW0UJDfP8s6cB0zbAizCjx0Z9fBoQOYtHrV eO24fkJuo68McBVD7RaFUCIN/zpBRWU= 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 v2 3/3] mm/alloc_tag: add the CONFIG_ARCH_NEEDS_WEAK_PER_CPU macro when statically defining the percpu variable _shared_alloc_tag Date: Fri, 13 Jun 2025 11:05:07 +0800 Message-Id: <099651f46b0b57f6c7890a64608dc7ca44df7764.1749779391.git.gehao@kylinos.cn> 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