summaryrefslogtreecommitdiffstats
path: root/net/sched/sch_fq_pie.c
Commit message (Collapse)AuthorAgeFilesLines
* treewide: Remove uninitialized_var() usageKees Cook2020-07-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs Signed-off-by: Kees Cook <keescook@chromium.org>
* net/sched: fix infinite loop in sch_fq_pieDavide Caratti2020-05-271-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | this command hangs forever: # tc qdisc add dev eth0 root fq_pie flows 65536 watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [tc:1028] [...] CPU: 1 PID: 1028 Comm: tc Not tainted 5.7.0-rc6+ #167 RIP: 0010:fq_pie_init+0x60e/0x8b7 [sch_fq_pie] Code: 4c 89 65 50 48 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 85 2a 02 00 00 48 8d 7d 10 4c 89 65 58 48 89 f8 48 c1 e8 03 42 80 3c 30 00 <0f> 85 a7 01 00 00 48 8d 7d 18 48 c7 45 10 46 c3 23 00 48 89 f8 48 RSP: 0018:ffff888138d67468 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffff9200018d2b2 RBX: ffff888139c1c400 RCX: ffffffffffffffff RDX: 000000000000c5e8 RSI: ffffc900000e5000 RDI: ffffc90000c69590 RBP: ffffc90000c69580 R08: fffffbfff79a9699 R09: fffffbfff79a9699 R10: 0000000000000700 R11: fffffbfff79a9698 R12: ffffc90000c695d0 R13: 0000000000000000 R14: dffffc0000000000 R15: 000000002347c5e8 FS: 00007f01e1850e40(0000) GS:ffff88814c880000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000067c340 CR3: 000000013864c000 CR4: 0000000000340ee0 Call Trace: qdisc_create+0x3fd/0xeb0 tc_modify_qdisc+0x3be/0x14a0 rtnetlink_rcv_msg+0x5f3/0x920 netlink_rcv_skb+0x121/0x350 netlink_unicast+0x439/0x630 netlink_sendmsg+0x714/0xbf0 sock_sendmsg+0xe2/0x110 ____sys_sendmsg+0x5b4/0x890 ___sys_sendmsg+0xe9/0x160 __sys_sendmsg+0xd3/0x170 do_syscall_64+0x9a/0x370 entry_SYSCALL_64_after_hwframe+0x44/0xa9 we can't accept 65536 as a valid number for 'nflows', because the loop on 'idx' in fq_pie_init() will never end. The extack message is correct, but it doesn't say that 0 is not a valid number for 'flows': while at it, fix this also. Add a tdc selftest to check correct validation of 'flows'. CC: Ivan Vecera <ivecera@redhat.com> Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Ivan Vecera <ivecera@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* pie: remove pie_vars->accu_prob_overflowsLeslie Monis2020-03-041-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | The variable pie_vars->accu_prob is used as an accumulator for probability values. Since probabilty values are scaled using the MAX_PROB macro denoting (2^64 - 1), pie_vars->accu_prob is likely to overflow as it is of type u64. The variable pie_vars->accu_prob_overflows counts the number of times the variable pie_vars->accu_prob overflows. The MAX_PROB macro needs to be equal to at least (2^39 - 1) in order to do precise calculations without any underflow. Thus MAX_PROB can be reduced to (2^56 - 1) without affecting the precision in calculations drastically. Doing so will eliminate the need for the variable pie_vars->accu_prob_overflows as the variable pie_vars->accu_prob will never overflow. Removing the variable pie_vars->accu_prob_overflows also reduces the size of the structure pie_vars to exactly 64 bytes. Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in> Signed-off-by: Gautam Ramakrishnan <gautamramk@gmail.com> Signed-off-by: Leslie Monis <lesliemonis@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: prevent a use after freeDan Carpenter2020-02-061-1/+1
| | | | | | | | | | | | | | The bug is that we call kfree_skb(skb) and then pass "skb" to qdisc_pkt_len(skb) on the next line, which is a use after free. Also Cong Wang points out that it's better to delay the actual frees until we drop the rtnl lock so we should use rtnl_kfree_skbs() instead of kfree_skb(). Cc: Cong Wang <xiyou.wangcong@gmail.com> Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: sched: add Flow Queue PIE packet schedulerMohit P. Tahiliani2020-01-231-0/+562
Principles: - Packets are classified on flows. - This is a Stochastic model (as we use a hash, several flows might be hashed to the same slot) - Each flow has a PIE managed queue. - Flows are linked onto two (Round Robin) lists, so that new flows have priority on old ones. - For a given flow, packets are not reordered. - Drops during enqueue only. - ECN capability is off by default. - ECN threshold (if ECN is enabled) is at 10% by default. - Uses timestamps to calculate queue delay by default. Usage: tc qdisc ... fq_pie [ limit PACKETS ] [ flows NUMBER ] [ target TIME ] [ tupdate TIME ] [ alpha NUMBER ] [ beta NUMBER ] [ quantum BYTES ] [ memory_limit BYTES ] [ ecnprob PERCENTAGE ] [ [no]ecn ] [ [no]bytemode ] [ [no_]dq_rate_estimator ] defaults: limit: 10240 packets, flows: 1024 target: 15 ms, tupdate: 15 ms (in jiffies) alpha: 1/8, beta : 5/4 quantum: device MTU, memory_limit: 32 Mb ecnprob: 10%, ecn: off bytemode: off, dq_rate_estimator: off Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in> Signed-off-by: Sachin D. Patil <sdp.sachin@gmail.com> Signed-off-by: V. Saicharan <vsaicharan1998@gmail.com> Signed-off-by: Mohit Bhasi <mohitbhasi1998@gmail.com> Signed-off-by: Leslie Monis <lesliemonis@gmail.com> Signed-off-by: Gautam Ramakrishnan <gautamramk@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>