From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 31544A2F6B for ; Tue, 8 Oct 2019 17:15:51 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id F28BD1C08E; Tue, 8 Oct 2019 17:15:50 +0200 (CEST) Received: from mail-pl1-f195.google.com (mail-pl1-f195.google.com [209.85.214.195]) by dpdk.org (Postfix) with ESMTP id 1D9091C07E for ; Tue, 8 Oct 2019 17:15:49 +0200 (CEST) Received: by mail-pl1-f195.google.com with SMTP id s17so8583873plp.6 for ; Tue, 08 Oct 2019 08:15:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=jUfxRy4IVJdTeivla5PpiDDwXyhR1lc2SO51q2LY+4s=; b=ARyOQeP7kXHZ4Rm9k9K8NwqnDapM0QIYVyV0XBO2GmRtFf88HsBpA8ysqa6jsAAht2 N+/RWXxz90uVyH0+Kaw81dqkG2h9o3ki3PrU3aEv6YJNDVokY/zwAuWZJcIJ06W+9paA +Vska13hzsOiXhI9ogKQElDPe+3YRIibrIbtfAk0BMJALdc+fgSP8pzKCPidR7E61FFz ALdUjgBlzL6wwlMcllf0p4b23QdrOWZiGxDg8iSNmmeIF4OyDNAcEkbVR0PAA4ROQaBn 2A1BmSlym1PXpc2E23VGg7mBKhxqlaNJXClKVmvCNOYvsVwdIbvE01wNwUWlQ4Y8u6Ow KuHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=jUfxRy4IVJdTeivla5PpiDDwXyhR1lc2SO51q2LY+4s=; b=ujisagXO0IIQc3urTDkQQ+4JNVcJvDPJZyZZP4J58ePgyqOHkBRB4qHWmUa8UrbNtU IVuA5AC7ppShR2J/qcT+7l/g0pWOLCmwFQ9lkgPpdqK3hGPcc56hmc0DaM1edJdwYFdi 3vtKgiZQbUbEe4l0LfcHsY89GYrxTxB8TnrT5b8/xKE6FXT/oUsdnmzCbZYaflzTY3ne nCzhg4veFQk9TupIsGgBCprayexT2g1N7P3WYo1ICpj2gIKPNWD7MGf8VY2ia1e/XTdW 1IQO871ojOTgJ4tuXH+J1fggrKJZF7P+Vlp7p4GEtFifc+rBLR1cqKA7g/9PfjEUsKdS n3YQ== X-Gm-Message-State: APjAAAUL3pdGc8HttVItEGfGQaCo3Ojd2iNCHBTuw2UbiygnKoniQvpX bBwlp1Xmt71NiNUyTm0V5JNpug== X-Google-Smtp-Source: APXvYqxtTEI+SVqOK6mc3BnAZDxTnV0KMtA2cv0ZJJwKMtrHu9gd6XCgvL9C8Ze7imaLlVzO9fHWnA== X-Received: by 2002:a17:902:a586:: with SMTP id az6mr36196695plb.12.1570547749179; Tue, 08 Oct 2019 08:15:49 -0700 (PDT) Received: from hermes.lan (204-195-22-127.wavecable.com. [204.195.22.127]) by smtp.gmail.com with ESMTPSA id q15sm5088856pgl.12.2019.10.08.08.15.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Oct 2019 08:15:49 -0700 (PDT) Date: Tue, 8 Oct 2019 08:15:47 -0700 From: Stephen Hemminger To: Bruce Richardson Cc: Jim Harris , dev@dpdk.org, anatoly.burakov@intel.com Message-ID: <20191008081547.2b002519@hermes.lan> In-Reply-To: <20191008083649.GA1856@bricha3-MOBL.ger.corp.intel.com> References: <156638268505.9344.18339364696357608254.stgit@jrharri1-skx> <157046280565.10885.5236700707414855268.stgit@jrharri1-skx> <20191007161854.0d4bbad0@hermes.lan> <20191008083649.GA1856@bricha3-MOBL.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH v2 RESEND] timer: remove check_tsc_flags() 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" On Tue, 8 Oct 2019 09:36:49 +0100 Bruce Richardson wrote: > On Mon, Oct 07, 2019 at 04:18:54PM -0700, Stephen Hemminger wrote: > > On Mon, 07 Oct 2019 08:40:05 -0700 Jim Harris > > wrote: > > > > > This code was added 7+ years ago: > > > > > > commit fb022b85bae4 ("timer: check TSC reliability") > > > > > > presumably when variant TSCs were still somewhat common? But this code > > > doesn't do anything except print a warning, and the warning doesn't > > > give any kind of advice to the user, so let's just remove it. > > > > > > While the warning has no functional meaning, the /proc/cpuinfo parsing > > > consumes a non-trivial amount of time which is especially noticeable in > > > secondary processes. On my test system, it consumes 21ms out of the > > > 66ms total execution time for rte_eal_init() in a secondary process. > > > > > > Signed-off-by: Jim Harris > > > > Yes this code is dead. > > > > Acked-by: Stephen Hemminger > > > > +1 for this. Even if it was needed, we should never parse /proc/cpuinfo, > since we have a DPDK function to query cpuid directly anyway. > > Acked-by: Bruce Richardson It also turns out that Hyper-V/Azure report unstable TSC because when VM is migrated there are blips in TSC. There upcoming changes to handle that in Hypervisor and Linux drivers.