From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Wang, Yipeng1" Subject: Re: [PATCH v3 4/7] hash: add memory ordering to avoid race conditions Date: Sat, 13 Oct 2018 01:56:15 +0000 Message-ID: References: <1539325918-125438-1-git-send-email-honnappa.nagarahalli@arm.com> <1539325918-125438-5-git-send-email-honnappa.nagarahalli@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Cc: "dev@dpdk.org" , "dharmik.thakkar@arm.com" , "gavin.hu@arm.com" , "nd@arm.com" , "Gobriel, Sameh" To: Honnappa Nagarahalli , "Richardson, Bruce" , "De Lara Guarch, Pablo" Return-path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id F22E31B3B1 for ; Sat, 13 Oct 2018 03:56:18 +0200 (CEST) In-Reply-To: <1539325918-125438-5-git-send-email-honnappa.nagarahalli@arm.com> Content-Language: en-US List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" When I applied this commit: fatal: sha1 information is lacking or useless (lib/librte_hash/rte_cuckoo_h= ash.c). Please double check. >-----Original Message----- >From: Honnappa Nagarahalli [mailto:honnappa.nagarahalli@arm.com] >Sent: Thursday, October 11, 2018 11:32 PM >To: Richardson, Bruce ; De Lara Guarch, Pablo = >Cc: dev@dpdk.org; Wang, Yipeng1 ; honnappa.nagarah= alli@arm.com; dharmik.thakkar@arm.com; >gavin.hu@arm.com; nd@arm.com >Subject: [PATCH v3 4/7] hash: add memory ordering to avoid race conditions > >Only race condition that can occur is - using the key store element >before the key write is completed. Hence, while inserting the element >the release memory order is used. Any other race condition is caught >by the key comparison. Memory orderings are added only where needed. >For ex: reads in the writer's context do not need memory ordering >as there is a single writer. [Wang, Yipeng]=20 I remember we discussed that this commit itself does not fix any bug/issue,= or enabling feature, it is supposed to work with the following patches to enable lock-free read-write concurrency. You separated the commits for e= asier review. If you plan to merge these commits and change the commit message it would b= e fine. Otherwise the current message title and content Is misleading. It sounds like a bug fix but actually not.