From 917229c24e871bbc3225a0227eb3f0faaa7aaa69 Mon Sep 17 00:00:00 2001 From: Wenwu Ma Date: Fri, 4 Mar 2022 16:24:24 +0000 Subject: [PATCH] examples/vhost: fix launch with physical port dpdk-vhost will fail to launch with a 40G i40e port because there are not enough mbufs. This patch adds a new option --total-num-mbufs, through which the user can set larger mbuf pool to avoid this problem. Fixes: 4796ad63ba1f ("examples/vhost: import userspace vhost application") Cc: stable@dpdk.org Signed-off-by: Wenwu Ma Reviewed-by: Chenbo Xia --- examples/vhost/main.c | 83 +++++++++++++++---------------------------- 1 file changed, 29 insertions(+), 54 deletions(-) diff --git a/examples/vhost/main.c b/examples/vhost/main.c index 68afd398bb..d94fabb060 100644 --- a/examples/vhost/main.c +++ b/examples/vhost/main.c @@ -33,6 +33,8 @@ #define MAX_QUEUES 128 #endif +#define NUM_MBUFS_DEFAULT 0x24000 + /* the maximum number of external ports supported */ #define MAX_SUP_PORTS 1 @@ -61,6 +63,9 @@ #define DMA_RING_SIZE 4096 +/* number of mbufs in all pools - if specified on command-line. */ +static int total_num_mbufs = NUM_MBUFS_DEFAULT; + struct dma_for_vhost dma_bind[RTE_MAX_VHOST_DEVICE]; int16_t dmas_id[RTE_DMADEV_DEFAULT_MAX]; static int dma_count; @@ -608,7 +613,8 @@ us_vhost_usage(const char *prgname) " --tx-csum [0|1] disable/enable TX checksum offload.\n" " --tso [0|1] disable/enable TCP segment offload.\n" " --client register a vhost-user socket as client mode.\n" - " --dmas register dma channel for specific vhost device.\n", + " --dmas register dma channel for specific vhost device.\n" + " --total-num-mbufs [0-N] set the number of mbufs to be allocated in mbuf pools, the default value is 147456.\n", prgname); } @@ -637,6 +643,8 @@ enum { OPT_BUILTIN_NET_DRIVER_NUM, #define OPT_DMAS "dmas" OPT_DMAS_NUM, +#define OPT_NUM_MBUFS "total-num-mbufs" + OPT_NUM_MBUFS_NUM, }; /* @@ -674,6 +682,8 @@ us_vhost_parse_args(int argc, char **argv) NULL, OPT_BUILTIN_NET_DRIVER_NUM}, {OPT_DMAS, required_argument, NULL, OPT_DMAS_NUM}, + {OPT_NUM_MBUFS, required_argument, + NULL, OPT_NUM_MBUFS_NUM}, {NULL, 0, 0, 0}, }; @@ -801,6 +811,19 @@ us_vhost_parse_args(int argc, char **argv) } break; + case OPT_NUM_MBUFS_NUM: + ret = parse_num_opt(optarg, INT32_MAX); + if (ret == -1) { + RTE_LOG(INFO, VHOST_CONFIG, + "Invalid argument for total-num-mbufs [0..N]\n"); + us_vhost_usage(prgname); + return -1; + } + + if (total_num_mbufs < ret) + total_num_mbufs = ret; + break; + case OPT_CLIENT_NUM: client_mode = 1; break; @@ -1730,57 +1753,6 @@ sigint_handler(__rte_unused int signum) exit(0); } -/* - * While creating an mbuf pool, one key thing is to figure out how - * many mbuf entries is enough for our use. FYI, here are some - * guidelines: - * - * - Each rx queue would reserve @nr_rx_desc mbufs at queue setup stage - * - * - For each switch core (A CPU core does the packet switch), we need - * also make some reservation for receiving the packets from virtio - * Tx queue. How many is enough depends on the usage. It's normally - * a simple calculation like following: - * - * MAX_PKT_BURST * max packet size / mbuf size - * - * So, we definitely need allocate more mbufs when TSO is enabled. - * - * - Similarly, for each switching core, we should serve @nr_rx_desc - * mbufs for receiving the packets from physical NIC device. - * - * - We also need make sure, for each switch core, we have allocated - * enough mbufs to fill up the mbuf cache. - */ -static void -create_mbuf_pool(uint16_t nr_port, uint32_t nr_switch_core, uint32_t mbuf_size, - uint32_t nr_queues, uint32_t nr_rx_desc, uint32_t nr_mbuf_cache) -{ - uint32_t nr_mbufs; - uint32_t nr_mbufs_per_core; - uint32_t mtu = 1500; - - if (mergeable) - mtu = 9000; - if (enable_tso) - mtu = 64 * 1024; - - nr_mbufs_per_core = (mtu + mbuf_size) * MAX_PKT_BURST / - (mbuf_size - RTE_PKTMBUF_HEADROOM); - nr_mbufs_per_core += nr_rx_desc; - nr_mbufs_per_core = RTE_MAX(nr_mbufs_per_core, nr_mbuf_cache); - - nr_mbufs = nr_queues * nr_rx_desc; - nr_mbufs += nr_mbufs_per_core * nr_switch_core; - nr_mbufs *= nr_port; - - mbuf_pool = rte_pktmbuf_pool_create("MBUF_POOL", nr_mbufs, - nr_mbuf_cache, 0, mbuf_size, - rte_socket_id()); - if (mbuf_pool == NULL) - rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n"); -} - static void reset_dma(void) { @@ -1860,8 +1832,11 @@ main(int argc, char *argv[]) * many queues here. We probably should only do allocation for * those queues we are going to use. */ - create_mbuf_pool(valid_num_ports, rte_lcore_count() - 1, MBUF_DATA_SIZE, - MAX_QUEUES, RTE_TEST_RX_DESC_DEFAULT, MBUF_CACHE_SIZE); + mbuf_pool = rte_pktmbuf_pool_create("MBUF_POOL", total_num_mbufs, + MBUF_CACHE_SIZE, 0, MBUF_DATA_SIZE, + rte_socket_id()); + if (mbuf_pool == NULL) + rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n"); if (vm2vm_mode == VM2VM_HARDWARE) { /* Enable VT loop back to let L2 switch to do it. */ -- 2.20.1