From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v2 net-next 06/12] qed: Add LL2 slowpath handling Date: Sun, 08 Oct 2017 21:40:28 -0700 (PDT) Message-ID: <20171008.214028.221318843312741195.davem@davemloft.net> References: <1507020902-4952-7-git-send-email-Michal.Kalderon@cavium.com> <20171003.101712.715882117516958741.davem@davemloft.net> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Ariel.Elior-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org To: Michal.Kalderon-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org Return-path: In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org From: "Kalderon, Michal" Date: Tue, 3 Oct 2017 18:05:32 +0000 > From: David Miller > Sent: Tuesday, October 3, 2017 8:17 PM >>> @@ -423,6 +423,41 @@ static void qed_ll2_rxq_parse_reg(struct qed_hwfn *p_hwfn, >>> } >>> >>> static int >>> +qed_ll2_handle_slowpath(struct qed_hwfn *p_hwfn, >>> + struct qed_ll2_info *p_ll2_conn, >>> + union core_rx_cqe_union *p_cqe, >>> + unsigned long *p_lock_flags) >>> +{ >>... >>> + spin_unlock_irqrestore(&p_rx->lock, *p_lock_flags); >>> + >> >>You can't drop this lock. >> >>Another thread can enter the loop of our caller and process RX queue >>entries, then we would return from here and try to process the same >>entries again. > > The lock is there to synchronize access to chains between qed_ll2_rxq_completion > and qed_ll2_post_rx_buffer. qed_ll2_rxq_completion can't be called from > different threads, the light l2 uses the single sp status block we have. > The reason we release the lock is to avoid a deadlock where as a result of calling > upper-layer driver it will potentially post additional rx-buffers. Ok, please repost this patch series. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html