From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E0C05239E8B; Tue, 26 Aug 2025 13:59:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756216795; cv=none; b=CpHVwGGEFHXDlgbSOWp7wFlNl58bKHPRHudRFVT+mfFcLMLalZIdyKfvq7nprMAqBsiX7jvSt4JswLecfv0fjZ0BSDLYwnRF/0TnEoxM7EpXIuhX9VmVm3NBWYpga0JNfp1LXDr71evd+4FEFhO5p/LpTZk0/ZsGs+NE3s2uuZE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756216795; c=relaxed/simple; bh=C6rgaEU+UlTNFdzQaQi3/gufCXB8uaY1dSzljFSY/Oo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZSzgIMNDHI8Ir4fqIHBYTEgM1hKM2LNSexaq6J5trmfzjZ3BRns2jiaSHGQkE6n+C5qcEf9t36BM0AbL0wYIU2hE2jb4+l8Lt+VDdc34XPz1gzRk/Dk6Lf7bQ5BMeu8qGumdwOW7ZFCNAibX8g2rYGCiQYqC6VJT+LR7QCrEWfQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SbsSZWvh; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="SbsSZWvh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 33F93C113CF; Tue, 26 Aug 2025 13:59:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756216794; bh=C6rgaEU+UlTNFdzQaQi3/gufCXB8uaY1dSzljFSY/Oo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SbsSZWvhEyQdFyJ4QKEKlfbm/YlSpVmTOPfGo6jHw+eAe9AuGC3sioFHtCcxkrAvO kQQJzpEkT4r8awx/p2aoo7HVvKAIE1C4Pg30mlkAw0hIcUEHCmQZTKm1mlKSvR4QYs bT8S7E4LOicyDCmnJP4wcaDvrnt3ZTOEsdAh+PQA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gerrard Tai , Cong Wang , Simon Horman , Jamal Hadi Salim , Paolo Abeni , Siddh Raman Pant Subject: [PATCH 5.15 547/644] codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog() Date: Tue, 26 Aug 2025 13:10:38 +0200 Message-ID: <20250826111000.082239565@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250826110946.507083938@linuxfoundation.org> References: <20250826110946.507083938@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cong Wang commit 342debc12183b51773b3345ba267e9263bdfaaef upstream. After making all ->qlen_notify() callbacks idempotent, now it is safe to remove the check of qlen!=0 from both fq_codel_dequeue() and codel_qdisc_dequeue(). Reported-by: Gerrard Tai Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Signed-off-by: Cong Wang Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250403211636.166257-1-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim Signed-off-by: Paolo Abeni Signed-off-by: Siddh Raman Pant Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_codel.c | 5 +---- net/sched/sch_fq_codel.c | 6 ++---- 2 files changed, 3 insertions(+), 8 deletions(-) --- a/net/sched/sch_codel.c +++ b/net/sched/sch_codel.c @@ -95,10 +95,7 @@ static struct sk_buff *codel_qdisc_deque &q->stats, qdisc_pkt_len, codel_get_enqueue_time, drop_func, dequeue_func); - /* We cant call qdisc_tree_reduce_backlog() if our qlen is 0, - * or HTB crashes. Defer it for next round. - */ - if (q->stats.drop_count && sch->q.qlen) { + if (q->stats.drop_count) { qdisc_tree_reduce_backlog(sch, q->stats.drop_count, q->stats.drop_len); q->stats.drop_count = 0; q->stats.drop_len = 0; --- a/net/sched/sch_fq_codel.c +++ b/net/sched/sch_fq_codel.c @@ -314,10 +314,8 @@ begin: } qdisc_bstats_update(sch, skb); flow->deficit -= qdisc_pkt_len(skb); - /* We cant call qdisc_tree_reduce_backlog() if our qlen is 0, - * or HTB crashes. Defer it for next round. - */ - if (q->cstats.drop_count && sch->q.qlen) { + + if (q->cstats.drop_count) { qdisc_tree_reduce_backlog(sch, q->cstats.drop_count, q->cstats.drop_len); q->cstats.drop_count = 0;