From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6B636C61CE8 for ; Thu, 12 Jun 2025 07:56:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0D7956B0093; Thu, 12 Jun 2025 03:56:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 088456B0095; Thu, 12 Jun 2025 03:56:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F06216B0096; Thu, 12 Jun 2025 03:56:04 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id D1BC46B0093 for ; Thu, 12 Jun 2025 03:56:04 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 55C271012E1 for ; Thu, 12 Jun 2025 07:56:04 +0000 (UTC) X-FDA: 83545990248.16.E862643 Received: from out-180.mta1.migadu.com (out-180.mta1.migadu.com [95.215.58.180]) by imf04.hostedemail.com (Postfix) with ESMTP id B0A9B4000D for ; Thu, 12 Jun 2025 07:56:02 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=iKgcHAeE; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf04.hostedemail.com: domain of hao.ge@linux.dev designates 95.215.58.180 as permitted sender) smtp.mailfrom=hao.ge@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1749714962; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=osSReSR8wlEOTjq5e/ERNMcEPZE3oL07rXtwliGT33w=; b=JERDCnaPiixEePYKz4oK/kQj4OLszltaoQiFtwH/IF8P3nGDWsBUpEZXexqoQPuZkYgSyx ekbpLY5AYrIyB9Bu3Mo1tGTLMUwen+L5WSjXDo3SxFM8pOvFBUA46IBjMNvSVLr7pLG+cW GfZfJrf08JEW1rXouZdOfAjyCmvMj74= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1749714962; a=rsa-sha256; cv=none; b=DNrH/OPxzfedjWN0qsUYGcMgOFSpquFjZHC3TJc5xSGPzc27hPumf3VGnd2rcTzAYcbCWr 78B3HSXzt7rY7vyoW6g8Gk1s/BG5XVl9gNacjUWLslxONuIGpFC+jQsMESjX0ue/Hmb5sr pvin+a9rA7gCsR+ks9Rw4t862Ziw3Tc= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=iKgcHAeE; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf04.hostedemail.com: domain of hao.ge@linux.dev designates 95.215.58.180 as permitted sender) smtp.mailfrom=hao.ge@linux.dev 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=1749714961; 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=osSReSR8wlEOTjq5e/ERNMcEPZE3oL07rXtwliGT33w=; b=iKgcHAeEXG1PiRchs8xEiZYE4HSrMocSps4LO+JObpwf/cheHd+GONnkkBh8Z/V8DF0gkV qJlpBXSSCxIX50TYftRSjvPj2JmRUoi+e1cyShxGwRG97OVMtym4mih1BGZGXlII1Ogtji YtEI0xGYIPB3CRphB9Sq0l2Ae/qUCw8= 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 1/5] mm/Kconfig: add ARCH_NEEDS_WEAK_PER_CPU option Date: Thu, 12 Jun 2025 15:54:24 +0800 Message-Id: <492346c5e787d639ddf6a3c86bdc14496696a498.1749702889.git.gehao@kylinos.cn> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Stat-Signature: tjg8c7tqouwm8tm39nzjgqnotedred11 X-Rspamd-Queue-Id: B0A9B4000D X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1749714962-245052 X-HE-Meta: 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 pJGb8S4K RDfOkoYBLSnaHHGbyLlkNIv1rA5JHj9R8drj/2bf3EqKj92BpBkqKnK+uNUxqKwg0N15tlHg/iUAJ6MaI9/CDqY7u7L1DM5/2fIKgdMIBdfmxWJGCg17xALM6e6s2jbJK/44NHSUDMt7LMIBX6W86sAjF09vgsI5ykMcdfxt4ONVbe71EdiREsmnCd4vwFBW5BYY/sOn4GUSsS9Pm7SGNQRtWOG3JmIHmfE8jApPK97rLT+dU7VPO8dZ6GQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Hao Ge Recently discovered this entry while checking kallsyms on ARM64: ffff800083e509c0 D _shared_alloc_tag If 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. Therefore,we need to implement isolation for this purpose. However,currently ARCH_NEEDS_WEAK_PER_CPU is a #define and is enclosed within the #if defined(MODULE) conditional block. When building the core kernel code for s390 or alpha architectures, ARCH_NEEDS_WEAK_PER_CPU remains undefined (as it is gated by #if defined(MODULE)). However,when building modules for these architectures,the macro is explicitly defined. Therefore,we need to make ARCH_NEEDS_WEAK_PER_CPU a Kconfig option. And replace all instances of ARCH_NEEDS_WEAK_PER_CPU in the kernel code with MODULE_NEEDS_WEAK_PER_CPU,gated by #ifdef CONFIG_ARCH_NEEDS_WEAK_PER_CPU. Then,when defining the percpu variable _shared_alloc_tag,wrap it with the CONFIG_ARCH_NEEDS_WEAK_PER_CPU condition. Therefore,we should add the ARCH_NEEDS_WEAK_PER_CPU option to the mm Kconfig file. Suggested-by: Suren Baghdasaryan Signed-off-by: Hao Ge --- mm/Kconfig | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/Kconfig b/mm/Kconfig index e113f713b493..36bb4d6fd360 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -929,6 +929,10 @@ config ARCH_SUPPORTS_PUD_PFNMAP def_bool y depends on ARCH_SUPPORTS_HUGE_PFNMAP && HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD +# s390 and alpha be enabled,see comments for DECLARE_PER_CPU_SECTION +config ARCH_NEEDS_WEAK_PER_CPU + bool + # # UP and nommu archs use km based percpu allocator # -- 2.25.1