From 62f64aed622b6055b5fc447e3e421c9351563fc8 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 7 May 2015 16:35:32 +0200 Subject: [PATCH] pktgen: introduce xmit_mode '' Introduce xmit_mode 'netif_receive' for pktgen which generates the packets using familiar pktgen commands, but feeds them into netif_receive_skb() instead of ndo_start_xmit(). Default mode is called 'start_xmit'. It is designed to test netif_receive_skb and ingress qdisc performace only. Make sure to understand how it works before using it for other rx benchmarking. Sample script 'pktgen.sh': \#!/bin/bash function pgset() { local result echo $1 > $PGDEV result=`cat $PGDEV | fgrep "Result: OK:"` if [ "$result" = "" ]; then cat $PGDEV | fgrep Result: fi } [ -z "$1" ] && echo "Usage: $0 DEV" && exit 1 ETH=$1 PGDEV=/proc/net/pktgen/kpktgend_0 pgset "rem_device_all" pgset "add_device $ETH" PGDEV=/proc/net/pktgen/$ETH pgset "xmit_mode netif_receive" pgset "pkt_size 60" pgset "dst 198.18.0.1" pgset "dst_mac 90:e2:ba:ff:ff:ff" pgset "count 10000000" pgset "burst 32" PGDEV=/proc/net/pktgen/pgctrl echo "Running... ctrl^C to stop" pgset "start" echo "Done" cat /proc/net/pktgen/$ETH Usage: $ sudo ./pktgen.sh eth2 ... Result: OK: 232376(c232372+d3) usec, 10000000 (60byte,0frags) 43033682pps 20656Mb/sec (20656167360bps) errors: 10000000 Raw netif_receive_skb speed should be ~43 million packet per second on 3.7Ghz x86 and 'perf report' should look like: 37.69% kpktgend_0 [kernel.vmlinux] [k] __netif_receive_skb_core 25.81% kpktgend_0 [kernel.vmlinux] [k] kfree_skb 7.22% kpktgend_0 [kernel.vmlinux] [k] ip_rcv 5.68% kpktgend_0 [pktgen] [k] pktgen_thread_worker If fib_table_lookup is seen on top, it means skb was processed by the stack. To benchmark netif_receive_skb only make sure that 'dst_mac' of your pktgen script is different from receiving device mac and it will be dropped by ip_rcv Signed-off-by: Alexei Starovoitov Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- Documentation/networking/pktgen.txt | 7 +++ net/core/pktgen.c | 82 +++++++++++++++++++++++++++-- 2 files changed, 84 insertions(+), 5 deletions(-) diff --git a/Documentation/networking/pktgen.txt b/Documentation/networking/pktgen.txt index 6199ee6a040b..747faccc4120 100644 --- a/Documentation/networking/pktgen.txt +++ b/Documentation/networking/pktgen.txt @@ -193,6 +193,10 @@ Examples: pgset "rate 300M" set rate to 300 Mb/s pgset "ratep 1000000" set rate to 1Mpps + pgset "xmit_mode netif_receive" RX inject into stack netif_receive_skb() + Works with "burst" but not with "clone_skb". + Default xmit_mode is "start_xmit". + Sample scripts ============== @@ -310,6 +314,9 @@ flowlen rate ratep +xmit_mode + + References: ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/ ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/ diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 43bb21507373..8f2687da058e 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -210,6 +210,10 @@ #define T_REMDEVALL (1<<2) /* Remove all devs */ #define T_REMDEV (1<<3) /* Remove one dev */ +/* Xmit modes */ +#define M_START_XMIT 0 /* Default normal TX */ +#define M_NETIF_RECEIVE 1 /* Inject packets into stack */ + /* If lock -- protects updating of if_list */ #define if_lock(t) spin_lock(&(t->if_lock)); #define if_unlock(t) spin_unlock(&(t->if_lock)); @@ -251,13 +255,14 @@ struct pktgen_dev { * we will do a random selection from within the range. */ __u32 flags; - int removal_mark; /* non-zero => the device is marked for - * removal by worker thread */ - + int xmit_mode; int min_pkt_size; int max_pkt_size; int pkt_overhead; /* overhead for MPLS, VLANs, IPSEC etc */ int nfrags; + int removal_mark; /* non-zero => the device is marked for + * removal by worker thread */ + struct page *page; u64 delay; /* nano-seconds */ @@ -620,6 +625,9 @@ static int pktgen_if_show(struct seq_file *seq, void *v) if (pkt_dev->node >= 0) seq_printf(seq, " node: %d\n", pkt_dev->node); + if (pkt_dev->xmit_mode == M_NETIF_RECEIVE) + seq_puts(seq, " xmit_mode: netif_receive\n"); + seq_puts(seq, " Flags: "); if (pkt_dev->flags & F_IPV6) @@ -1081,7 +1089,8 @@ static ssize_t pktgen_if_write(struct file *file, if (len < 0) return len; if ((value > 0) && - (!(pkt_dev->odev->priv_flags & IFF_TX_SKB_SHARING))) + ((pkt_dev->xmit_mode == M_NETIF_RECEIVE) || + !(pkt_dev->odev->priv_flags & IFF_TX_SKB_SHARING))) return -ENOTSUPP; i += len; pkt_dev->clone_skb = value; @@ -1134,7 +1143,7 @@ static ssize_t pktgen_if_write(struct file *file, return len; i += len; - if ((value > 1) && + if ((value > 1) && (pkt_dev->xmit_mode == M_START_XMIT) && (!(pkt_dev->odev->priv_flags & IFF_TX_SKB_SHARING))) return -ENOTSUPP; pkt_dev->burst = value < 1 ? 1 : value; @@ -1160,6 +1169,35 @@ static ssize_t pktgen_if_write(struct file *file, sprintf(pg_result, "ERROR: node not possible"); return count; } + if (!strcmp(name, "xmit_mode")) { + char f[32]; + + memset(f, 0, 32); + len = strn_len(&user_buffer[i], sizeof(f) - 1); + if (len < 0) + return len; + + if (copy_from_user(f, &user_buffer[i], len)) + return -EFAULT; + i += len; + + if (strcmp(f, "start_xmit") == 0) { + pkt_dev->xmit_mode = M_START_XMIT; + } else if (strcmp(f, "netif_receive") == 0) { + /* clone_skb set earlier, not supported in this mode */ + if (pkt_dev->clone_skb > 0) + return -ENOTSUPP; + + pkt_dev->xmit_mode = M_NETIF_RECEIVE; + } else { + sprintf(pg_result, + "xmit_mode -:%s:- unknown\nAvailable modes: %s", + f, "start_xmit, netif_receive\n"); + return count; + } + sprintf(pg_result, "OK: xmit_mode=%s", f); + return count; + } if (!strcmp(name, "flag")) { char f[32]; memset(f, 0, 32); @@ -3320,6 +3358,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) unsigned int burst = ACCESS_ONCE(pkt_dev->burst); struct net_device *odev = pkt_dev->odev; struct netdev_queue *txq; + struct sk_buff *skb; int ret; /* If device is offline, then don't send */ @@ -3357,6 +3396,38 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) if (pkt_dev->delay && pkt_dev->last_ok) spin(pkt_dev, pkt_dev->next_tx); + if (pkt_dev->xmit_mode == M_NETIF_RECEIVE) { + skb = pkt_dev->skb; + skb->protocol = eth_type_trans(skb, skb->dev); + atomic_add(burst, &skb->users); + local_bh_disable(); + do { + ret = netif_receive_skb(skb); + if (ret == NET_RX_DROP) + pkt_dev->errors++; + pkt_dev->sofar++; + pkt_dev->seq_num++; + if (atomic_read(&skb->users) != burst) { + /* skb was queued by rps/rfs or taps, + * so cannot reuse this skb + */ + atomic_sub(burst - 1, &skb->users); + /* get out of the loop and wait + * until skb is consumed + */ + pkt_dev->last_ok = 1; + break; + } + /* skb was 'freed' by stack, so clean few + * bits and reuse it + */ +#ifdef CONFIG_NET_CLS_ACT + skb->tc_verd = 0; /* reset reclass/redir ttl */ +#endif + } while (--burst > 0); + goto out; /* Skips xmit_mode M_START_XMIT */ + } + txq = skb_get_tx_queue(odev, pkt_dev->skb); local_bh_disable(); @@ -3404,6 +3475,7 @@ xmit_more: unlock: HARD_TX_UNLOCK(odev, txq); +out: local_bh_enable(); /* If pkt_dev->count is zero, then run forever */