From patchwork Thu Oct 15 12:04:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Burakov, Anatoly" X-Patchwork-Id: 80896 X-Patchwork-Delegate: thomas@monjalon.net Return-Path: X-Original-To: patchwork@inbox.dpdk.org Delivered-To: patchwork@inbox.dpdk.org Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 2C95BA04DB; Thu, 15 Oct 2020 14:07:36 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 93DFB1E556; Thu, 15 Oct 2020 14:05:17 +0200 (CEST) Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by dpdk.org (Postfix) with ESMTP id 952341E559 for ; Thu, 15 Oct 2020 14:05:09 +0200 (CEST) IronPort-SDR: Z2EjlfoQo2oT98jvAtXvlOAyW8bVluO16Y2RTfBKj4Y2RzbcsLOfs1K6crARMaO+lxxKI2onsC oFTEnYvtKJ0w== X-IronPort-AV: E=McAfee;i="6000,8403,9774"; a="227977241" X-IronPort-AV: E=Sophos;i="5.77,378,1596524400"; d="scan'208";a="227977241" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Oct 2020 05:04:58 -0700 IronPort-SDR: fAHcWKu0to8ZF6Dmpl1GDnadcizF3OgS2UB+B1Mhd+na30YJYByVSQzdSBGI4ml/d+IldTHF+u 6nJ5XtUxFARA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,378,1596524400"; d="scan'208";a="314485696" Received: from silpixa00399498.ir.intel.com (HELO silpixa00399498.ger.corp.intel.com) ([10.237.222.52]) by orsmga003.jf.intel.com with ESMTP; 15 Oct 2020 05:04:55 -0700 From: Anatoly Burakov To: dev@dpdk.org Cc: Liang Ma , David Hunt , konstantin.ananyev@intel.com, jerinjacobk@gmail.com, bruce.richardson@intel.com, thomas@monjalon.net, timothy.mcdaniel@intel.com, gage.eads@intel.com, chris.macnamara@intel.com Date: Thu, 15 Oct 2020 13:04:15 +0100 Message-Id: <1b4dd60949bbada468f9fe9fcdc3f5357aaa1ec8.1602763439.git.anatoly.burakov@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: In-Reply-To: References: Subject: [dpdk-dev] [PATCH v7 10/10] doc: update programmer's guide for power library X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" From: Liang Ma Update programmer's guide to document PMD power management usage. Signed-off-by: Liang Ma Signed-off-by: Anatoly Burakov Acked-by: David Hunt --- Notes: v5: - Moved l3fwd-power update to the l3fwd-power-related commit - Some rewordings and clarifications doc/guides/prog_guide/power_man.rst | 42 +++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/doc/guides/prog_guide/power_man.rst b/doc/guides/prog_guide/power_man.rst index 0a3755a901..38c64d31e4 100644 --- a/doc/guides/prog_guide/power_man.rst +++ b/doc/guides/prog_guide/power_man.rst @@ -192,6 +192,45 @@ User Cases ---------- The mechanism can applied to any device which is based on polling. e.g. NIC, FPGA. +PMD Power Management API +------------------------ + +Abstract +~~~~~~~~ +Existing power management mechanisms require developers to change application +design or change code to make use of it. The PMD power management API provides a +convenient alternative by utilizing Ethernet PMD RX callbacks, and triggering +power saving whenever empty poll count reaches a certain number. + + * UMWAIT/UMONITOR + + This power saving scheme will put the CPU into optimized power state and use + the UMWAIT/UMONITOR instructions to monitor the Ethernet PMD RX descriptor + address, and wake the CPU up whenever there's new traffic. + + * Pause + + This power saving scheme will use the `rte_pause` function to avoid busy + polling. + + * Frequency scaling + + This power saving scheme will use existing power library functionality to + scale the core frequency up/down depending on traffic volume. + + +.. note:: + + Currently, this power management API is limited to mandatory mapping of 1 + queue to 1 core (multiple queues are supported, but they must be polled from + different cores). + +API Overview for PMD Power Management +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +* **Queue Enable**: Enable specific power scheme for certain queue/port/core + +* **Queue Disable**: Disable power scheme for certain queue/port/core + References ---------- @@ -200,3 +239,6 @@ References * The :doc:`../sample_app_ug/vm_power_management` chapter in the :doc:`../sample_app_ug/index` section. + +* The :doc:`../sample_app_ug/rxtx_callbacks` + chapter in the :doc:`../sample_app_ug/index` section.