/* * Mausezahn - A fast versatile traffic generator * Copyright (C) 2008-2010 Herbert Haas * * This program is free software; you can redistribute it and/or modify it under * the terms of the GNU General Public License version 2 as published by the * Free Software Foundation. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License along with * this program; if not, see http://www.gnu.org/licenses/gpl-2.0.html * */ #include "mz.h" #include "cli.h" int tx_switch(struct cli_def *cli) { // These handles are only used when creating L3 and above packets. libnet_t *l; // the context libnet_ptag_t t2=0, t3=0, t4=0; // handles to layers double cpu_time_used; switch (mode) { case BYTE_STREAM: send_eth(); break; case ARP: if (send_arp()==-1) return 0; break; case BPDU: if (send_bpdu()==-1) return 0; break; case CDP: if (send_cdp()==-1) return 0; break; case IP: // From now on a new much more modular method is used: l = get_link_context(); t3 = create_ip_packet(l); // t3 can be used for later header changes if (!quiet) complexity(); if (tx.packet_mode==0) // Ethernet manipulation features does NOT use ARP to determine eth_dst t2 = create_eth_frame(l, t3, t4); // t2 can be used for later header changes else send_frame (l, t3, t4); // NOTE: send_frame also destroys context finaly break; case ICMP: tx.ip_proto = 1; l = get_link_context(); t4 = create_icmp_packet(l); // t4 can be used for later header changes if (t4==-1) return 0; t3 = create_ip_packet(l); // t3 can be used for later header changes if (!quiet) complexity(); if (tx.packet_mode==0) // Ethernet manipulation features does NOT use ARP to determine eth_dst t2 = create_eth_frame(l, t3, t4); // t2 can be used for later header changes else send_frame (l, t3, t4); // NOTE: send_frame also destroys context finaly break; case UDP: tx.ip_proto = 17; l = get_link_context(); t4 = create_udp_packet(l); // t4 can be used for later header changes if (t4==-1) return 0; t3 = create_ip_packet(l); // t3 can be used for later header changes if (!quiet) complexity(); if (tx.packet_mode==0) // Ethernet manipulation features does NOT use ARP to determine eth_dst t2 = create_eth_frame(l, t3, t4); // t2 can be used for later header changes else send_frame (l, t3, t4); // NOTE: send_frame also destroys context finaly break; case TCP: tx.ip_proto = 6; l = get_link_context(); t4 = create_tcp_packet(l); // t4 can be used for later header changes if (t4==-1) return 0; t3 = create_ip_packet(l); // t3 can be used for later header changes if (!quiet) complexity(); if (tx.packet_mode==0) // Ethernet manipulation features does NOT use ARP to determine eth_dst t2 = create_eth_frame(l, t3, t4); // t2 can be used for later header changes else send_frame (l, t3, t4); // NOTE: send_frame also destroys context finaly break; case DNS: tx.ip_proto = 17; l = get_link_context(); if (create_dns_packet()==-1) return 0; t4 = create_udp_packet(l); // t4 can be used for later header changes t3 = create_ip_packet(l); // t3 can be used for later header changes if (!quiet) complexity(); if (tx.packet_mode==0) // Ethernet manipulation features does NOT use ARP to determine eth_dst t2 = create_eth_frame(l, t3, t4); // t2 can be used for later header changes else send_frame (l, t3, t4); // NOTE: send_frame also destroys context finaly break; case RTP: tx.ip_proto = 17; l = get_link_context(); if (create_rtp_packet()==-1) return 0; cli_print(cli, "RTP mode! (count=%u, delay=%u usec)\n", tx.count, tx.delay); t4 = create_udp_packet(l); // t4 can be used for later header changes t3 = create_ip_packet(l); // t3 can be used for later header changes if (!quiet) complexity(); if (tx.packet_mode==0) // Ethernet manipulation features does NOT use ARP to determine eth_dst t2 = create_eth_frame(l, t3, t4); // t2 can be used for later header changes else send_frame (l, t3, t4); // NOTE: send_frame also destroys context finaly break; case RX_RTP: // Receive RTP packets rcv_rtp_init(); rcv_rtp(); break; case SYSLOG: tx.ip_proto = 17; l = get_link_context(); if (create_syslog_packet()==-1) return 0; t4 = create_udp_packet(l); // t4 can be used for later header changes t3 = create_ip_packet(l); // t3 can be used for later header changes if (!quiet) complexity(); if (tx.packet_mode==0) // Ethernet manipulation features does NOT use ARP to determine eth_dst t2 = create_eth_frame(l, t3, t4); // t2 can be used for later header changes else send_frame (l, t3, t4); // NOTE: send_frame also destroys context finaly break; case LLDP: // start with a new concept here //l = get_link_context(); //(void) create_lldp_packet(); // // // printf("SIZE=%lu\n",sizeof(struct tx_struct)); break; default: cli_print(cli,"Unknown mode!\n"); return (1); } // ***** Re-init packet functions: ***** tx.ip_payload_s = 0; tx.udp_len = 0; tx.tcp_payload_s = 0; tx.icmp_payload_s = 0; tx.cdp_sum = 0; mode = 0; // ************************************** mz_stop = clock(); cpu_time_used = ((double) (mz_stop - mz_start)) / CLOCKS_PER_SEC; if (cpu_time_used > 0) { total_d /= cpu_time_used; cli_print(cli, "%.2f seconds (%.Lf packets per second)\n",cpu_time_used,total_d); } return 0; } ion
percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'drivers/usb/Makefile')