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 00774A0524; Wed, 5 May 2021 08:52:52 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 0DE4141161; Wed, 5 May 2021 08:51:36 +0200 (CEST) Received: from wout4-smtp.messagingengine.com (wout4-smtp.messagingengine.com [64.147.123.20]) by mails.dpdk.org (Postfix) with ESMTP id 4E3F6410F9 for ; Wed, 5 May 2021 08:51:31 +0200 (CEST) Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailout.west.internal (Postfix) with ESMTP id 23CAB10E2; Wed, 5 May 2021 02:51:30 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute2.internal (MEProxy); Wed, 05 May 2021 02:51:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s=fm1; bh= nGaZR7yKomPcOP/TX/h2YeVlDoTnlpAogPTi4iZo5aM=; b=ISC0mEtHN2k2m2a4 5Ds4QQVgel5IMmcbCoFAVFnhWSPOfoqf8kQKUPiN88APcE1brZiiSXU6bYPRGHP6 2cbb7AbVe076RNharhg+lqWniOSc3J2iRK9IKLtseIt0XirEmRaz/ci4azjE3t+r 7xAeH+Hp2ysM9r1Qyq1H+zh/X1enCKY0lps9eQ4lUegDvdwhwu/afqWmwVOVCRhU dnI7bDAymP5y6FDfNVVglFL3neHdN5dfxT5+fCOL5A2NzqefZGtWE0GD8Gt4k5Js PcgD9rMOTIimJ7/tjmnVZoZw/FtL4GAozWqLYWIDliIhR0ky3T8d6HjStv1akyl+ jKNsEA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm2; bh=nGaZR7yKomPcOP/TX/h2YeVlDoTnlpAogPTi4iZo5 aM=; b=kfVAe1+E7e/hE3hhnlpqt3HfvGmCNH3FxE9fyivD1PEHCKKsovLfC+WAv C4kpElxQjU1h3mNd/k67hovU5z76+Jskr2kZ6k7aOTk7+S4YbLlWrm6MrhogPQvo +DSo23pnCVB6+iUr3XKtaznPGhCylhMQg+l3e4isIJoq7Z0VImrkpGzDSGH/oubH UwLUJ2gSzaensint03By2tjdpFC4Xjv6LGyJ2feyB7AmbvFmNhI1F6wuQmmnQVCc cH6Xv5DyHkOYhAhps8yqj286V7U1YKvui+2aAlVI4CyUAhDPHDlvHcYKcN94OMwm +xJrFhxIfY090emRnvIdZiytq3yfw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledrvdefjedguddtjecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enucfjughrpefhvffufffkjghfggfgtgesthhqredttddtudenucfhrhhomhepvfhhohhm rghsucfoohhnjhgrlhhonhcuoehthhhomhgrshesmhhonhhjrghlohhnrdhnvghtqeenuc ggtffrrghtthgvrhhnpeehhefffffguefhveetueehveeggedtgeegieeuveefhfduiedt uefhjedthedtheenucffohhmrghinhepughivgdrnhgvthdpfhhrvggvsghsugdrohhrgh enucfkphepjeejrddufeegrddvtdefrddukeegnecuvehluhhsthgvrhfuihiivgeptden ucfrrghrrghmpehmrghilhhfrhhomhepthhhohhmrghssehmohhnjhgrlhhonhdrnhgvth X-ME-Proxy: Received: from xps.localnet (184.203.134.77.rev.sfr.net [77.134.203.184]) by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 5 May 2021 02:51:28 -0400 (EDT) From: Thomas Monjalon To: "Min Hu (Connor)" , Morten =?ISO-8859-1?Q?Br=F8rup?= Cc: dev@dpdk.org, ferruh.yigit@intel.com, skori@marvell.com, jerinj@marvell.com Date: Wed, 05 May 2021 08:51:27 +0200 Message-ID: <15286141.XL2fGeQaG1@thomas> In-Reply-To: <98CBD80474FA8B44BF855DF32C47DC35C61747@smartserver.smartshare.dk> References: <1619597563-56716-1-git-send-email-humin29@huawei.com> <8952614.77jy4Yh1ug@thomas> <98CBD80474FA8B44BF855DF32C47DC35C61747@smartserver.smartshare.dk> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" Subject: Re: [dpdk-dev] [PATCH v2] eal: fix use wrong time API 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 Sender: "dev" 05/05/2021 08:26, Morten Br=F8rup: > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Thomas Monjalon > > Sent: Wednesday, May 5, 2021 8:14 AM > >=20 > > 04/05/2021 21:12, Morten Br=F8rup: > > > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Thomas > > Monjalon > > > > Sent: Tuesday, May 4, 2021 6:50 PM > > > > > > > > 29/04/2021 04:10, Min Hu (Connor): > > > > > Currently, the mp uses gettimeofday() API to get the time, and > > used > > > > as > > > > > timeout parameter. > > > > > > > > > > But the time which gets from gettimeofday() API isn't > > monotonically > > > > > increasing. The process may fail if the system time is changed. > > > > > > > > > > This fixes it by using clock_gettime() API with monotonic > > > > attribution. > > > > > > > > > > Fixes: 783b6e54971d ("eal: add synchronous multi-process > > > > communication") > > > > > Fixes: f05e26051c15 ("eal: add IPC asynchronous request") > > > > > Cc: stable@dpdk.org > > > > > > > > > > Signed-off-by: Chengwen Feng > > > > > Signed-off-by: Min Hu (Connor) > > > > > --- > > > > [...] > > > > > --- a/lib/eal/common/eal_common_proc.c > > > > > +++ b/lib/eal/common/eal_common_proc.c > > > > > - if (gettimeofday(&now, NULL) < 0) { > > > > > - RTE_LOG(ERR, EAL, "Cannot get current time\n"); > > > > > - goto no_trigger; > > > > > - } > > > > > - ts_now.tv_nsec =3D now.tv_usec * 1000; > > > > > - ts_now.tv_sec =3D now.tv_sec; > > > > > + clock_gettime(CLOCK_MONOTONIC, &ts_now); > > > > > > > > Why not testing the return value? > > > > > > Because it is guaranteed not to fail. Ref: > > > https://linux.die.net/man/3/clock_gettime > > > https://www.freebsd.org/cgi/man.cgi?query=3Dclock_gettime > >=20 > > I see "return 0 for success, or -1 for failure". > > Where is it said it cannot fail? >=20 > I'm sorry about being unclear. Referring to the "Errors" chapter in the f= unction's man page, this function call is guaranteed not to fail with these= parameters. So there is no need to check the return value. I don't agree. Especially for this error: "The clk_id specified is not supported on this system." How can you be sure it is always supported for any system we try to run this code now and in future experiments?