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 1731746EB9 for ; Wed, 10 Sep 2025 08:49:42 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 0BA4A40270; Wed, 10 Sep 2025 08:49:42 +0200 (CEST) Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com [209.85.221.50]) by mails.dpdk.org (Postfix) with ESMTP id 81C8B402C4 for ; Wed, 10 Sep 2025 08:49:40 +0200 (CEST) Received: by mail-wr1-f50.google.com with SMTP id ffacd0b85a97d-3df726ecff3so3375901f8f.3 for ; Tue, 09 Sep 2025 23:49:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind.com; s=google; t=1757486980; x=1758091780; darn=dpdk.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=ZFUuatgEI5hoLWfFMDM/uWu4qbdOiqxfJR9+iwy+o38=; b=LYX/lmkw3x+XZETbVA3mYlkq1Quae1DjGznCSsR1dY9VV7By0B0MbjtNZaUqq82XUY IwE7SIfc+IW/MjamoPJ65aW2zS32+e25NCNywx3CJ30TYE1KLHw+4O2kfocOz81VCyLn N9RqWQ2Rbxxgso23TcKQ1w1YXN8TsS+SCenx5PMLJcTQosbahmeCsBwr15PH7lqtOSM3 AcLMrOpktoZbpMW9uwO8JmLjJ1GqPtbU7kHi9CcjrEr6Fh9MzFJxVgQJII4ucE0Xme+8 MAxeSnsDlCLhbayPaLW1/nQQA6D1zrzWvg9WxZ1gsrIEMGfZlsUMjRpsJbVtFTRjA1aP tN7Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1757486980; x=1758091780; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ZFUuatgEI5hoLWfFMDM/uWu4qbdOiqxfJR9+iwy+o38=; b=BvSJzgZxKfv44huUJYxTaBL3kODfj6r9FtV/vfJljQMhF2m6lCImJlCuO85C5WBgKh l+bwx/laeQWl6pmglFS2qHyeaWcBv3RXwQYM0CLR6sCv82evBbNy3dSfFMqW//UBwhwi F+Pw4VScIF6x8UqcUquDibxUpYMqv3Z1siWIvTNDuSzx4d5ZAUBRzUTZ1YV9aezYLd6V vU+dHi2Uf8/oPBpFIdgkp8v+42oWaYeEaAMOmOdUbxZuEaTuGrb7hE3oyNRWRuRaF0sv XuQ6dejDLY9A/9eyEarWfG7f+JV28Y3BvA/qc5R98rP1gbC4+WOB5rIsvMVkeeBvrJt8 8bJQ== X-Forwarded-Encrypted: i=1; AJvYcCUyB5PFvR7CcDGMt96hJrh7xq6l9yxog/vbOJZ8wNyeksIHCectzaDUkjDnPDDGd+3oOnmLNXQ=@dpdk.org X-Gm-Message-State: AOJu0Yz2yDW1HiLbE2kylWM1/y+MSqNoPum1ZUmV2HO/S6+b00Auva2h Pp3+g12dD2nDPlKJHb0oQNZIIU3yMMxGlQYbXGEbVt3LCIGiCqT03elBWUBAp4tS6g== X-Gm-Gg: ASbGncsxshXbm3oby1mW06p5Y77DKByAR1itqlp98AkO8GhOS1L20iosnUBze4gjGk3 1C5HunKXMJ6RnxrUPd0J0VCFw/n9+QwxF5dmF64zfgCB+OALdl5At7a/OYI4LhoFLxCz89npLiH PKZiBS92wRe06XoRHUnJd+t64eYNaxxnOXAAfDB+76Fjv3fPRyDTq1gAmVNKGmCxBC8qPPyFS+w Lmvt2rN64vDqWG2t4K2XDCc2eomIcnObxxRBeyf1rFqADY1L41f6V23qSLP9PJOwbSBDsDR3qTh AxV0CJDr88mv/1O8QT21ewuBmx2Oga357bjT836ueRONJug0Eb4HvWCqlU/xuDksy8GKM0hkIZQ 2Oif3kOiuYtnj+OQZbgT5JhyD3Ic3aU0d/0HRtw== X-Google-Smtp-Source: AGHT+IGIGh785bXhJ9VRlDIpmVmlBDlLjcc/6t664fb9Q/N5OsVpyUIpScX7QulxlnWZb+IwbcoZRA== X-Received: by 2002:a05:6000:24c5:b0:3e7:458e:f69 with SMTP id ffacd0b85a97d-3e7458e1a33mr10150253f8f.56.1757486980007; Tue, 09 Sep 2025 23:49:40 -0700 (PDT) Received: from [10.17.1.39] ([185.13.181.2]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3e75224d7f5sm5822210f8f.59.2025.09.09.23.49.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 09 Sep 2025 23:49:39 -0700 (PDT) Message-ID: <151c401a-87dc-423c-8bae-89d325dc8c90@6wind.com> Date: Wed, 10 Sep 2025 08:49:38 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [V3] net/qede: reduce the optimization level for gcc > 11 To: Stephen Hemminger Cc: dev@dpdk.org, Thomas Monjalon , Devendra Singh Rawat , Alok Prasad , Jerin Jacob , Olivier Matz , Edwin Brossette , stable@dpdk.org References: <20250908070414.1297844-1-thierry.herbelot@6wind.com> <20250909054023.3263401-1-thierry.herbelot@6wind.com> <20250909091724.2ea0615e@hermes.local> Content-Language: en-US From: Thierry Herbelot In-Reply-To: <20250909091724.2ea0615e@hermes.local> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: stable-bounces@dpdk.org Hello Stephen, On 9/9/25 18:17, Stephen Hemminger wrote: > On Tue, 9 Sep 2025 07:40:23 +0200 > Thierry Herbelot wrote: > >> The qede PMD stopped working under Ubuntu-24.04 (using gcc-13) when >> compiled with -O3 (default level for all DPDK code). A bug is opened >> for this issue (see Link). The same issue is also seen with gcc-12 >> and gcc-14. The issue is not seen with clang-20. >> >> A first workaround is to just disable all optimizations (-O0), which >> restores packet Rx with Qlogic NICs. However, the performance impact >> is not acceptable (around 50% drop). >> >> A better compromise is to use -O1 for the qede PMD: >> - there is some perf impact, >> - but the PMD is working as expected (packets are correctly received). >> >> When compiling with both -O2 and -O3 and gcc > 11, there is no packet >> reception when using the qede PMD. The root cause could be missing >> 'volatile' keywords or missing memory barriers in the qede PMD code. >> >> Link: https://bugs.dpdk.org/show_bug.cgi?id=1379 >> Signed-off-by: Thierry Herbelot > > Which rx_burst gets used on that hardware? > > Is there any indication of errors (like rx_mbuf_alloc_failed) in the stats. > > The driver does not appear to have any write barrier after updating the consumed packets. > > Would this help? > diff --git a/drivers/net/qede/qede_rxtx.c b/drivers/net/qede/qede_rxtx.c > index 25e28fd9f6..1b5109d966 100644 > --- a/drivers/net/qede/qede_rxtx.c > +++ b/drivers/net/qede/qede_rxtx.c > @@ -1295,6 +1295,8 @@ static inline void qede_rx_bd_ring_consume(struct qede_rx_queue *rxq) > { > ecore_chain_consume(&rxq->rx_bd_ring); > rxq->sw_rx_cons++; > + > + rte_wmb(); > } > I just checked with this patch, but the error is still present: testpmd> show fwd stats all ---------------------- Forward statistics for port 0 ---------------------- RX-packets: 0 RX-dropped: 10 RX-total: 10 RX-error: 0 RX-nombufs: 10 TX-packets: 0 TX-dropped: 0 TX-total: 0 ---------------------------------------------------------------------------- The error chain is: RX-nombufs => (testpmd) stats.rx_nombuf => (qede) p_stats->common.no_buff_discards => (qede/base) HILO_64_REGPAIR(mstats.no_buff_discard) (internal to the NIC) Best regards Thierry > > > -- Thierry Herbelot