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 X-Spam-Level: X-Spam-Status: No, score=-5.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 191C3C433E4 for ; Tue, 18 Aug 2020 07:15:13 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BD75A20738 for ; Tue, 18 Aug 2020 07:15:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WDdMh2o7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BD75A20738 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 1BF6B6B0008; Tue, 18 Aug 2020 03:15:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 170998D0005; Tue, 18 Aug 2020 03:15:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 05EE76B000C; Tue, 18 Aug 2020 03:15:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0206.hostedemail.com [216.40.44.206]) by kanga.kvack.org (Postfix) with ESMTP id E07F16B0008 for ; Tue, 18 Aug 2020 03:15:11 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 9EADC181AEF1A for ; Tue, 18 Aug 2020 07:15:11 +0000 (UTC) X-FDA: 77162828022.24.hair67_3c079a62701d Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin24.hostedemail.com (Postfix) with ESMTP id 70DED1A4A7 for ; Tue, 18 Aug 2020 07:15:11 +0000 (UTC) X-HE-Tag: hair67_3c079a62701d X-Filterd-Recvd-Size: 3208 Received: from mail-pj1-f52.google.com (mail-pj1-f52.google.com [209.85.216.52]) by imf21.hostedemail.com (Postfix) with ESMTP for ; Tue, 18 Aug 2020 07:15:11 +0000 (UTC) Received: by mail-pj1-f52.google.com with SMTP id ha11so8839380pjb.1 for ; Tue, 18 Aug 2020 00:15:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:cc:from:subject:message-id:date:user-agent:mime-version :content-language:content-transfer-encoding; bh=jF2h8tKaiRfnNJtwUujz1zyW68b7xQIOHq9yD+WIWhc=; b=WDdMh2o7Ky6orGYuIf9m1a/Dh7ThNHUlsXtCZIKxNwXafQXZFaceTJ2azjzNZOBlEt weeJC9ZPqe9II5tH9MKXoZOgzgf7l+hyjAoaF4oI+DMtUM/1Pk+g/TALo8uj1goefbps /vAkSCgy61xssqDP7IQL8LJ1Nmn7RPQUBCjJYE62c7J0eftcByxRpeXx8dAyVlA9XmEg 76x6mZ8YcRO6gGqrvNTkqIjESLMPMV1Nehtzg9skw6SBXsnTxCFnpvn569Zt0SzrV7N9 w/vaO6YbFVhyaxRAUmCPU/psQ4ldN1GKU5YUz4X26yhUXzhJBhAhFLFn2/zlJLPYwHN3 3e2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:cc:from:subject:message-id:date:user-agent :mime-version:content-language:content-transfer-encoding; bh=jF2h8tKaiRfnNJtwUujz1zyW68b7xQIOHq9yD+WIWhc=; b=hm7G9Z5Vnwv6Kx7xhiSVZhD8LBJduQM2PeNTMUY/rZveExhqCCHYWWc9/MW9Gj8fjg kf5VauW8gG75jV6LrmbUV8+zZdrBIQGzdYYjKCFfrSt3bHN1f3uKjy5ccG6RqeOzMIyD EWvcFwdUT67lqdRSxOhTun62gzsaDtFo9P3yUMNgPlRC+hQmL/+nnXUnMgJG0CalOxPB NW1UsojHNTt4V6jF6QkGlVlbGxN9Yzi3xLBihFJDmKttYgC355r4h9NtJYaPMx0ECjhk gJQquCXoGErHplU7xlZ+PBPlWwLFLCEi9/hxztaUVovSuPvnBMiEY8v5exnspWUGk1Vc F4xA== X-Gm-Message-State: AOAM530yyMdnJhwQMP1FC9er6rqMc8kwioce3o7TKdtenyhSR0AHUAMv YcHl/fA1IqeUBN172DHYku4= X-Google-Smtp-Source: ABdhPJyY3Hw8mocN4TDpq5hXbhWY0lpSAeUY6ZL7wY99AtbOxwKqLi36smq/1Mg+WMqB4w5AdpnqFg== X-Received: by 2002:a17:902:7291:: with SMTP id d17mr14053685pll.141.1597734910117; Tue, 18 Aug 2020 00:15:10 -0700 (PDT) Received: from [192.168.1.7] ([1.23.2.9]) by smtp.gmail.com with ESMTPSA id x23sm22839047pfi.60.2020.08.18.00.15.08 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 18 Aug 2020 00:15:09 -0700 (PDT) To: linux-mm@kvack.org Cc: jglisse@redhat.com From: Valmiki Subject: Regarding HMM Message-ID: Date: Tue, 18 Aug 2020 12:45:06 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 70DED1A4A7 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 X-Bogosity: Ham, tests=bogofilter, spamicity=0.197626, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi All, Im trying to understand heterogeneous memory management, i have following doubts. If HMM is being used we dont have to use DMA controller on device for memory transfers ? Without DMA if software is managing page faults and migrations, will there be any performance impacts ? Is HMM targeted for any specific use cases where DMA controller is not there on device ? Regards, Valmiki