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 0EFC0A055B; Tue, 25 Feb 2020 21:15:57 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 2084B1BF8D; Tue, 25 Feb 2020 21:15:56 +0100 (CET) Received: from inbox.dpdk.org (xvm-172-178.dc0.ghst.net [95.142.172.178]) by dpdk.org (Postfix) with ESMTP id 077E51F1C for ; Tue, 25 Feb 2020 21:15:55 +0100 (CET) Received: by inbox.dpdk.org (Postfix, from userid 33) id BA9BBA055C; Tue, 25 Feb 2020 21:15:54 +0100 (CET) From: bugzilla@dpdk.org To: dev@dpdk.org Date: Tue, 25 Feb 2020 20:15:54 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: DPDK X-Bugzilla-Component: testpmd X-Bugzilla-Version: 19.11 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: cfb@hpe.com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: Normal X-Bugzilla-Assigned-To: dev@dpdk.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter target_milestone Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://bugs.dpdk.org/ Auto-Submitted: auto-generated X-Auto-Response-Suppress: All MIME-Version: 1.0 Subject: [dpdk-dev] [Bug 409] testpmd sometimes does not correctly show RX-missed on Mellanox NICs 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" https://bugs.dpdk.org/show_bug.cgi?id=3D409 Bug ID: 409 Summary: testpmd sometimes does not correctly show RX-missed on Mellanox NICs Product: DPDK Version: 19.11 Hardware: All OS: All Status: UNCONFIRMED Severity: normal Priority: Normal Component: testpmd Assignee: dev@dpdk.org Reporter: cfb@hpe.com Target Milestone: --- When running testpmd using the Mellanox driver (mlx5), the value shown for RX-missed will overflow and show an extremely large value at times. This appears to occur when /sys/devices/.../inifiband/mlx5_*/ports/*/hw_counters/out_of_buffer rolls o= ver. This value is an unsigned 32 bit and testpmd uses an unsigned 64 bit to sto= re the value. The initial value is read when testpmd is started, then a new va= lue is read while it is running. If the value read is less than the initial read (after a rollover occurs), the difference will result in a negative value (= or in the case of unsigned storage, an extremely large value). The calculation occurs in mlx5_stats_get(): mlx5_read_ib_stat(priv, "out_of_buffer", &tmp.imissed); tmp.imissed -=3D priv->stats_ctrl.imissed_base; Where the stored value, priv->stats_ctrl.imissed_base, contains a larger va= lue than the value stored in tmp.imissed. Two possible solutions are to change the Mellanox drivers to use an unsigne= d 64 bit value for out_of_buffer in sysfs (so that it doesn't rollover), or to modify the mlx5 code to account for the rollover. --=20 You are receiving this mail because: You are the assignee for the bug.=