From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id D7B9FA054F; Sat, 11 Jun 2022 02:00:17 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 8F0B640222; Sat, 11 Jun 2022 02:00:17 +0200 (CEST) Received: from mail-pf1-f181.google.com (mail-pf1-f181.google.com [209.85.210.181]) by mails.dpdk.org (Postfix) with ESMTP id F3E0F40041 for ; Sat, 11 Jun 2022 02:00:15 +0200 (CEST) Received: by mail-pf1-f181.google.com with SMTP id g205so752156pfb.11 for ; Fri, 10 Jun 2022 17:00:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=8VUP7m57id7nvQkTPEJp3+8EOG62H0c474fu4xxeodU=; b=R5T8qJBmT3mJl94/Wfyo5zMjtakg+F77/VbSODB2awlloBIoosGbIOMt9F8cSRvXj6 rbMc+UFYLKEMVVM3DcSAhfxiXOvknfZLHpDt5aGbE52HE0HwFmhDpA7HS+DkknZP4HS0 uoVBPu2sLR/F0dPukXLqi8+jzhF4rJv5icLYoEkKWbUxy1jC+419S56X3ieCTnzWvrD4 zDVqhL5VZRGwtwSZBjxJJDvuS4J2wg52yI/3gWsw35V49/AIHxn2/n5MvR5YHl8UMr8j l+J8TB0kHEsqTT2u0DE9Am4bIg+37TGj3ETPPHjq9CB2LQvG4xA2Qwm/QgrPMNKml85O CDmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=8VUP7m57id7nvQkTPEJp3+8EOG62H0c474fu4xxeodU=; b=OxFmpojU/oSyfzaoznnUwAJmHDyvd+B5AjY42o7WCM9IGeCzzlfeZXkU/id4xpOf8X D/scmjFNAtbGKpkCTklepdLY153ZzTPo7M2y1YloWiIvEAEr/BO8Jxxy4UHQZgGwumv4 XLruK7MsVn5aem+PlPpT6b7gwmWLpcPr5RrpGJTNQxpia49TirbP743TzfLUdw1IANxO biVlDki2AfM3CKk5OatfkWuujK7WE98ZEhx2eP4fpcfYBbQ9+6F3DHVUJaWqfv8p7TDD OCIT+kyWnglAgjN0qFb5GxpaflflZhP5ybIrzXD2hvv2Z++HQqYqqUTqZgKEpN90A+sp DyMg== X-Gm-Message-State: AOAM533WSWg0lS1hzXppAQeoLOpYlr6smO1ODTLsvT2F5gUchHJH0ZEh U7AvmV2bqn66xtypmScHwNhytw== X-Google-Smtp-Source: ABdhPJz/zO1J4jcnMFlVDXr6ujU+2UBfXmjrIUXLXlxJtscsGSLiCHIa9F3YOjZmBt/UVpoCBFsXNg== X-Received: by 2002:a05:6a00:1c5c:b0:505:7469:134a with SMTP id s28-20020a056a001c5c00b005057469134amr48294099pfw.16.1654905615104; Fri, 10 Jun 2022 17:00:15 -0700 (PDT) Received: from hermes.local (204-195-112-199.wavecable.com. [204.195.112.199]) by smtp.gmail.com with ESMTPSA id jf17-20020a170903269100b00163f183ab76sm166411plb.152.2022.06.10.17.00.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Jun 2022 17:00:14 -0700 (PDT) Date: Fri, 10 Jun 2022 17:00:11 -0700 From: Stephen Hemminger To: Tyler Retzlaff Cc: dev@dpdk.org, anatoly.burakov@intel.com Subject: Re: [PATCH] doc/eal: add caveat about spinlocks from non-pinned threads Message-ID: <20220610170011.65272cf7@hermes.local> In-Reply-To: <20220610234815.GE14494@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net> References: <20220610152819.38737-1-stephen@networkplumber.org> <20220610234815.GE14494@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On Fri, 10 Jun 2022 16:48:15 -0700 Tyler Retzlaff wrote: > > > > ++ locking > > + > > + If a pthread, that is not pinned to an lcore acquires a lock such as a > > nit: suggest not using term pthread but instead just say thread as not > to imply a specific platform/implementation. > > > + DPDK based lock (rte_spinlock, rte_rwlock, rte_ticketlock, rte_mcslock) > > + then there is a possibility of large application delays. > > + The problem is that if a thread is scheduled off the CPU while it holds > > + a lock, then other threads will waste time spinning on the lock until > > 'until the lock holder' -> 'until the thread holding the lock' > > but i'm not really fussed, just a suggestion. Sure, that wording was from existing pthread_spin_init() man page