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 86240C43334 for ; Sat, 25 Jun 2022 02:27:22 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A98078E0283; Fri, 24 Jun 2022 22:27:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A48256B00EF; Fri, 24 Jun 2022 22:27:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 90F988E0283; Fri, 24 Jun 2022 22:27:21 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 825A76B00EA for ; Fri, 24 Jun 2022 22:27:21 -0400 (EDT) Received: from smtpin12.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 54C3660283 for ; Sat, 25 Jun 2022 02:27:21 +0000 (UTC) X-FDA: 79615171482.12.6A01A56 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf09.hostedemail.com (Postfix) with ESMTP id C7114140023 for ; Sat, 25 Jun 2022 02:27:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1656124040; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Ou1XEP0BPo6icwSFpk7PWKqyE25oGMYYgA4xnkE+mU8=; b=LHWYsZh6bK/787QZVaWpLKlsFdJd0aqDobZiqoI/ru+2VPNI73AXrItvcoR0W+O+S14R40 sH5Z8vOXsN9IZ8Y1EG9l+u59pHWNgN7wBh1cRK0Zo2XJo3pMUDeZyoYjEJAMiS6zpUmiG/ 7P0wNVGzLlbbx5j9Cfo+fqn2nghOjY0= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-281-cwe8s5YqPBCVDny9Z74y8Q-1; Fri, 24 Jun 2022 22:27:16 -0400 X-MC-Unique: cwe8s5YqPBCVDny9Z74y8Q-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C8637811E75; Sat, 25 Jun 2022 02:27:15 +0000 (UTC) Received: from [10.22.8.37] (unknown [10.22.8.37]) by smtp.corp.redhat.com (Postfix) with ESMTP id 252C1492CA5; Sat, 25 Jun 2022 02:27:15 +0000 (UTC) Message-ID: <0b08a52a-b348-ca3f-6ea2-4e75498a76b1@redhat.com> Date: Fri, 24 Jun 2022 22:27:14 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [Question] vmalloc latency in RT-Linux Content-Language: en-US To: Sebastian Andrzej Siewior , Baoquan He Cc: Zhipeng Shi , linux-mm@kvack.org, linux-rt-users@vger.kernel.org, tglx@linutronix.de, shengjian.xu@horizon.ai, schspa@gmail.com, peterz@infradead.org References: <20220621121547.GB37196@ubuntu20> From: Waiman Long In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=LHWYsZh6; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf09.hostedemail.com: domain of longman@redhat.com has no SPF policy when checking 170.10.129.124) smtp.mailfrom=longman@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656124041; 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-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Ou1XEP0BPo6icwSFpk7PWKqyE25oGMYYgA4xnkE+mU8=; b=AN/vKrSDWsa7FUv5RNeV3ALOUYdQC1HbWjgr3P8DIYtgnnBA4BAi6dG0KSdlfDpUmUgbTk yPz3/4+HrP+AK8Acj2kg4Tm0bn7bOmcM6HJf5+fk1xw5352fNeZ2FA99Q0kThMaNxU3CxG YB+VRJu+x5NF7d7ob9qsR2r772jRO6M= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656124041; a=rsa-sha256; cv=none; b=Pcnf+Bnn3Eed0E+urGXQH9MOtukwOC2xLTpN+fqVmW4lgoT2sb+jPCTnV80xDo0LvDmGvc Qn6+cA1uXBH0IzzBcy2ariK9as+Y/HzIuTdaCIii7y3cyZ3SQJLC24fEChchG9bJT9gZTF UzJpTx5tTJlxesvljDedL/sy8ngUiLI= X-Stat-Signature: z9b8rrrka7xwtyg8jd1kc6itmbh7rqun X-Rspamd-Queue-Id: C7114140023 X-Rspam-User: Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=LHWYsZh6; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf09.hostedemail.com: domain of longman@redhat.com has no SPF policy when checking 170.10.129.124) smtp.mailfrom=longman@redhat.com X-Rspamd-Server: rspam12 X-HE-Tag: 1656124040-883281 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 6/24/22 02:46, Sebastian Andrzej Siewior wrote: > On 2022-06-24 10:39:43 [+0800], Baoquan He wrote: >> Then this is a good chance to reconsider it, maybe with a test from Zhipeng. > I reconsidered and it was dropped purpose, see > https://lore.kernel.org/lkml/YT80AB8%2FG59QBSVq@hirez.programming.kicks-ass.net/ I do agree that is_contended may not that useful for rwlock, but it can be useful for spinlock. Will you consider a version just for rt_spinlock? Cheers, Longman