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ovs/lib/dpif-netdev.h

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/*
* Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2015 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef DPIF_NETDEV_H
#define DPIF_NETDEV_H 1
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include "dpif.h"
#include "openvswitch/types.h"
#include "dp-packet.h"
#include "packets.h"
#ifdef __cplusplus
extern "C" {
#endif
/* Enough headroom to add a vlan tag, plus an extra 2 bytes to allow IP
* headers to be aligned on a 4-byte boundary. */
enum { DP_NETDEV_HEADROOM = 2 + VLAN_HEADER_LEN };
bool dpif_is_netdev(const struct dpif *);
#define NR_QUEUE 1
netdev-dpdk: Fix race condition with DPDK mempools in non pmd threads DPDK mempools rely on rte_lcore_id() to implement a thread-local cache. Our non pmd threads had rte_lcore_id() == 0. This allowed concurrent access to the "thread-local" cache, causing crashes. This commit resolves the issue with the following changes: - Every non pmd thread has the same lcore_id (0, for management reasons), which is not shared with any pmd thread (lcore_id for pmd threads now start from 1) - DPDK mbufs must be allocated/freed in pmd threads. When there is the need to use mempools in non pmd threads, like in dpdk_do_tx_copy(), a mutex must be held. - The previous change does not allow us anymore to pass DPDK mbufs to handler threads: therefore this commit partially revert 143859ec63d45e. Now packets are copied for upcall processing. We can remove the extra memcpy by processing upcalls in the pmd thread itself. With the introduction of the extra locking, the packet throughput will be lower in the following cases: - When using internal (tap) devices with DPDK devices on the same datapath. Anyway, to support internal devices efficiently, we needed DPDK KNI devices, which will be proper pmd devices and will not need this locking. - When packets are processed in the slow path by non pmd threads. This overhead can be avoided by handling the upcalls directly in pmd threads (a change that has already been proposed by Ryan Wilson) Also, the following two fixes have been introduced: - In dpdk_free_buf() use rte_pktmbuf_free_seg() instead of rte_mempool_put(). This allows OVS to run properly with CONFIG_RTE_LIBRTE_MBUF_DEBUG DPDK option - Do not bulk free mbufs in a transmission queue. They may belong to different mempools Signed-off-by: Daniele Di Proietto <ddiproietto@vmware.com> Acked-by: Pravin B Shelar <pshelar@nicira.com>
2014-07-17 14:29:36 -07:00
#define NR_PMD_THREADS 1
#ifdef __cplusplus
}
#endif
#endif /* netdev.h */