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2020-07-16Revert "net: sched: Pass root lock to Qdisc_ops.enqueue"Petr Machata
This reverts commit aebe4426ccaa4838f36ea805cdf7d76503e65117. Signed-off-by: Petr Machata <petrm@mellanox.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-07-07net/sched: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29net: sched: Pass root lock to Qdisc_ops.enqueuePetr Machata
A following patch introduces qevents, points in qdisc algorithm where packet can be processed by user-defined filters. Should this processing lead to a situation where a new packet is to be enqueued on the same port, holding the root lock would lead to deadlocks. To solve the issue, qevent handler needs to unlock and relock the root lock when necessary. To that end, add the root lock argument to the qdisc op enqueue, and propagate throughout. Signed-off-by: Petr Machata <petrm@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-30net: sched: fix `tc -s class show` no bstats on class with nolock subqueuesDust Li
When a classful qdisc's child qdisc has set the flag TCQ_F_CPUSTATS (pfifo_fast for example), the child qdisc's cpu_bstats should be passed to gnet_stats_copy_basic(), but many classful qdisc didn't do that. As a result, `tc -s class show dev DEV` always return 0 for bytes and packets in this case. Pass the child qdisc's cpu_bstats to gnet_stats_copy_basic() to fix this issue. The qstats also has this problem, but it has been fixed in 5dd431b6b9 ("net: sched: introduce and use qstats read...") and bstats still remains buggy. Fixes: 22e0f8b9322c ("net: sched: make bstats per cpu and estimator RCU safe") Signed-off-by: Dust Li <dust.li@linux.alibaba.com> Signed-off-by: Tony Lu <tonylu@linux.alibaba.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-27net: sched: multiq: don't call qdisc_put() while holding tree lockVlad Buslov
Recent changes that removed rtnl dependency from rules update path of tc also made tcf_block_put() function sleeping. This function is called from ops->destroy() of several Qdisc implementations, which in turn is called by qdisc_put(). Some Qdiscs call qdisc_put() while holding sch tree spinlock, which results sleeping-while-atomic BUG. Steps to reproduce for multiq: tc qdisc add dev ens1f0 root handle 1: multiq tc qdisc add dev ens1f0 parent 1:10 handle 50: sfq perturb 10 ethtool -L ens1f0 combined 2 tc qdisc change dev ens1f0 root handle 1: multiq Resulting dmesg: [ 5539.419344] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909 [ 5539.420945] in_atomic(): 1, irqs_disabled(): 0, pid: 27658, name: tc [ 5539.422435] INFO: lockdep is turned off. [ 5539.423904] CPU: 21 PID: 27658 Comm: tc Tainted: G W 5.3.0-rc8+ #721 [ 5539.425400] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 5539.426911] Call Trace: [ 5539.428380] dump_stack+0x85/0xc0 [ 5539.429823] ___might_sleep.cold+0xac/0xbc [ 5539.431262] __mutex_lock+0x5b/0x960 [ 5539.432682] ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 5539.434103] ? __nla_validate_parse+0x51/0x840 [ 5539.435493] ? tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 5539.436903] tcf_chain0_head_change_cb_del.isra.0+0x1b/0xf0 [ 5539.438327] tcf_block_put_ext.part.0+0x21/0x50 [ 5539.439752] tcf_block_put+0x50/0x70 [ 5539.441165] sfq_destroy+0x15/0x50 [sch_sfq] [ 5539.442570] qdisc_destroy+0x5f/0x160 [ 5539.444000] multiq_tune+0x14a/0x420 [sch_multiq] [ 5539.445421] tc_modify_qdisc+0x324/0x840 [ 5539.446841] rtnetlink_rcv_msg+0x170/0x4b0 [ 5539.448269] ? netlink_deliver_tap+0x95/0x400 [ 5539.449691] ? rtnl_dellink+0x2d0/0x2d0 [ 5539.451116] netlink_rcv_skb+0x49/0x110 [ 5539.452522] netlink_unicast+0x171/0x200 [ 5539.453914] netlink_sendmsg+0x224/0x3f0 [ 5539.455304] sock_sendmsg+0x5e/0x60 [ 5539.456686] ___sys_sendmsg+0x2ae/0x330 [ 5539.458071] ? ___sys_recvmsg+0x159/0x1f0 [ 5539.459461] ? do_wp_page+0x9c/0x790 [ 5539.460846] ? __handle_mm_fault+0xcd3/0x19e0 [ 5539.462263] __sys_sendmsg+0x59/0xa0 [ 5539.463661] do_syscall_64+0x5c/0xb0 [ 5539.465044] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 5539.466454] RIP: 0033:0x7f1fe08177b8 [ 5539.467863] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 5 4 [ 5539.470906] RSP: 002b:00007ffe812de5d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 5539.472483] RAX: ffffffffffffffda RBX: 000000005d8135e3 RCX: 00007f1fe08177b8 [ 5539.474069] RDX: 0000000000000000 RSI: 00007ffe812de640 RDI: 0000000000000003 [ 5539.475655] RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000182e9b0 [ 5539.477203] R10: 0000000000404eda R11: 0000000000000246 R12: 0000000000000001 [ 5539.478699] R13: 000000000047f640 R14: 0000000000000000 R15: 0000000000000000 Rearrange locking in multiq_tune() in following ways: - In loop that removes Qdiscs from disabled queues, call qdisc_purge_queue() instead of qdisc_tree_flush_backlog() on Qdisc that is being destroyed. Save the Qdisc in temporary allocated array and call qdisc_put() on each element of the array after sch tree lock is released. This is safe to do because Qdiscs have already been reset by qdisc_purge_queue() inside sch tree lock critical section. - Do the same change for second loop that initializes Qdiscs for newly enabled queues in multiq_tune() function. Since sch tree lock is obtained and released on each iteration of this loop, just call qdisc_put() directly outside of critical section. Don't verify that old Qdisc is not noop_qdisc before releasing reference to it because such check is already performed by qdisc_put*() functions. Fixes: c266f64dbfa2 ("net: sched: protect block state with mutex") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 228 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528171438.107155473@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-01net: sched: introduce and use qdisc tree flush/purge helpersPaolo Abeni
The same code to flush qdisc tree and purge the qdisc queue is duplicated in many places and in most cases it does not respect NOLOCK qdisc: the global backlog len is used and the per CPU values are ignored. This change addresses the above, factoring-out the relevant code and using the helpers introduced by the previous patch to fetch the correct backlog len. Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-01net: sched: introduce and use qstats read helpersPaolo Abeni
Classful qdiscs can't access directly the child qdiscs backlog length: if such qdisc is NOLOCK, per CPU values should be accounted instead. Most qdiscs no not respect the above. As a result, qstats fetching for most classful qdisc is currently incorrect: if the child qdisc is NOLOCK, it always reports 0 len backlog. This change introduces a pair of helpers to safely fetch both backlog and qlen and use them in stats class dumping functions, fixing the above issue and cleaning a bit the code. DRR needs also to access the child qdisc queue length, so it needs custom handling. Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-25net: sched: rename qdisc_destroy() to qdisc_put()Vlad Buslov
Current implementation of qdisc_destroy() decrements Qdisc reference counter and only actually destroy Qdisc if reference counter value reached zero. Rename qdisc_destroy() to qdisc_put() in order for it to better describe the way in which this function currently implemented and used. Extract code that deallocates Qdisc into new private qdisc_destroy() function. It is intended to be shared between regular qdisc_put() and its unlocked version that is introduced in next patch in this series. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sch: api: add extack support in qdisc_create_dfltAlexander Aring
This patch adds extack support for the function qdisc_create_dflt which is a common used function in the tc subsystem. Callers which are interested in the receiving error can assign extack to get a more detailed information why qdisc_create_dflt failed. The function qdisc_create_dflt will also call an init callback which can fail by any per-qdisc specific handling. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sch: api: add extack support in tcf_block_getAlexander Aring
This patch adds extack support for the function tcf_block_get which is a common used function in the tc subsystem. Callers which are interested in the receiving error can assign extack to get a more detailed information why tcf_block_get failed. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack for graft callbackAlexander Aring
This patch adds extack support for graft callback to prepare per-qdisc specific changes for extack. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack for block callbackAlexander Aring
This patch adds extack support for block callback to prepare per-qdisc specific changes for extack. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack for change qdisc opsAlexander Aring
This patch adds extack support for change callback for qdisc ops structtur to prepare per-qdisc specific changes for extack. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack for init callbackAlexander Aring
This patch adds extack support for init callback to prepare per-qdisc specific changes for extack. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: fix coding style issuesAlexander Aring
This patch fix checkpatch issues for upcomming patches according to the sched api file. It changes mostly how to check on null pointer. Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22net: sched: mark expected switch fall-throughsGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16net: sched: store Qdisc pointer in struct blockJiri Pirko
Prepare for removal of tp->q and store Qdisc pointer in the block structure. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Three cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-30sch_multiq: fix double free on init failureNikolay Aleksandrov
The below commit added a call to ->destroy() on init failure, but multiq still frees ->queues on error in init, but ->queues is also freed by ->destroy() thus we get double free and corrupted memory. Very easy to reproduce (eth0 not multiqueue): $ tc qdisc add dev eth0 root multiq RTNETLINK answers: Operation not supported $ ip l add dumdum type dummy (crash) Trace log: [ 3929.467747] general protection fault: 0000 [#1] SMP [ 3929.468083] Modules linked in: [ 3929.468302] CPU: 3 PID: 967 Comm: ip Not tainted 4.13.0-rc6+ #56 [ 3929.468625] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 3929.469124] task: ffff88003716a700 task.stack: ffff88005872c000 [ 3929.469449] RIP: 0010:__kmalloc_track_caller+0x117/0x1be [ 3929.469746] RSP: 0018:ffff88005872f6a0 EFLAGS: 00010246 [ 3929.470042] RAX: 00000000000002de RBX: 0000000058a59000 RCX: 00000000000002df [ 3929.470406] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff821f7020 [ 3929.470770] RBP: ffff88005872f6e8 R08: 000000000001f010 R09: 0000000000000000 [ 3929.471133] R10: ffff88005872f730 R11: 0000000000008cdd R12: ff006d75646d7564 [ 3929.471496] R13: 00000000014000c0 R14: ffff88005b403c00 R15: ffff88005b403c00 [ 3929.471869] FS: 00007f0b70480740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000 [ 3929.472286] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3929.472677] CR2: 00007ffcee4f3000 CR3: 0000000059d45000 CR4: 00000000000406e0 [ 3929.473209] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3929.474109] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3929.474873] Call Trace: [ 3929.475337] ? kstrdup_const+0x23/0x25 [ 3929.475863] kstrdup+0x2e/0x4b [ 3929.476338] kstrdup_const+0x23/0x25 [ 3929.478084] __kernfs_new_node+0x28/0xbc [ 3929.478478] kernfs_new_node+0x35/0x55 [ 3929.478929] kernfs_create_link+0x23/0x76 [ 3929.479478] sysfs_do_create_link_sd.isra.2+0x85/0xd7 [ 3929.480096] sysfs_create_link+0x33/0x35 [ 3929.480649] device_add+0x200/0x589 [ 3929.481184] netdev_register_kobject+0x7c/0x12f [ 3929.481711] register_netdevice+0x373/0x471 [ 3929.482174] rtnl_newlink+0x614/0x729 [ 3929.482610] ? rtnl_newlink+0x17f/0x729 [ 3929.483080] rtnetlink_rcv_msg+0x188/0x197 [ 3929.483533] ? rcu_read_unlock+0x3e/0x5f [ 3929.483984] ? rtnl_newlink+0x729/0x729 [ 3929.484420] netlink_rcv_skb+0x6c/0xce [ 3929.484858] rtnetlink_rcv+0x23/0x2a [ 3929.485291] netlink_unicast+0x103/0x181 [ 3929.485735] netlink_sendmsg+0x326/0x337 [ 3929.486181] sock_sendmsg_nosec+0x14/0x3f [ 3929.486614] sock_sendmsg+0x29/0x2e [ 3929.486973] ___sys_sendmsg+0x209/0x28b [ 3929.487340] ? do_raw_spin_unlock+0xcd/0xf8 [ 3929.487719] ? _raw_spin_unlock+0x27/0x31 [ 3929.488092] ? __handle_mm_fault+0x651/0xdb1 [ 3929.488471] ? check_chain_key+0xb0/0xfd [ 3929.488847] __sys_sendmsg+0x45/0x63 [ 3929.489206] ? __sys_sendmsg+0x45/0x63 [ 3929.489576] SyS_sendmsg+0x19/0x1b [ 3929.489901] entry_SYSCALL_64_fastpath+0x23/0xc2 [ 3929.490172] RIP: 0033:0x7f0b6fb93690 [ 3929.490423] RSP: 002b:00007ffcee4ed588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 3929.490881] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f0b6fb93690 [ 3929.491198] RDX: 0000000000000000 RSI: 00007ffcee4ed5d0 RDI: 0000000000000003 [ 3929.491521] RBP: ffff88005872ff98 R08: 0000000000000001 R09: 0000000000000000 [ 3929.491801] R10: 00007ffcee4ed350 R11: 0000000000000246 R12: 0000000000000002 [ 3929.492075] R13: 000000000066f1a0 R14: 00007ffcee4f5680 R15: 0000000000000000 [ 3929.492352] ? trace_hardirqs_off_caller+0xa7/0xcf [ 3929.492590] Code: 8b 45 c0 48 8b 45 b8 74 17 48 8b 4d c8 83 ca ff 44 89 ee 4c 89 f7 e8 83 ca ff ff 49 89 c4 eb 49 49 63 56 20 48 8d 48 01 4d 8b 06 <49> 8b 1c 14 48 89 c2 4c 89 e0 65 49 0f c7 08 0f 94 c0 83 f0 01 [ 3929.493335] RIP: __kmalloc_track_caller+0x117/0x1be RSP: ffff88005872f6a0 Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation") Fixes: f07d1501292b ("multiq: Further multiqueue cleanup") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25net_sched: remove tc class reference countingWANG Cong
For TC classes, their ->get() and ->put() are always paired, and the reference counting is completely useless, because: 1) For class modification and dumping paths, we already hold RTNL lock, so all of these ->get(),->change(),->put() are atomic. 2) For filter bindiing/unbinding, we use other reference counter than this one, and they should have RTNL lock too. 3) For ->qlen_notify(), it is special because it is called on ->enqueue() path, but we already hold qdisc tree lock there, and we hold this tree lock when graft or delete the class too, so it should not be gone or changed until we release the tree lock. Therefore, this patch removes ->get() and ->put(), but: 1) Adds a new ->find() to find the pointer to a class by classid, no refcnt. 2) Move the original class destroy upon the last refcnt into ->delete(), right after releasing tree lock. This is fine because the class is already removed from hash when holding the lock. For those who also use ->put() as ->unbind(), just rename them to reflect this change. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06net: sched: introduce a TRAP control actionJiri Pirko
There is need to instruct the HW offloaded path to push certain matched packets to cpu/kernel for further analysis. So this patch introduces a new TRAP control action to TC. For kernel datapath, this action does not make much sense. So with the same logic as in HW, new TRAP behaves similar to STOLEN. The skb is just dropped in the datapath (and virtually ejected to an upper level, which does not exist in case of kernel). Signed-off-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Yotam Gigi <yotamg@mellanox.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: introduce tcf block infractructureJiri Pirko
Currently, the filter chains are direcly put into the private structures of qdiscs. In order to be able to have multiple chains per qdisc and to allow filter chains sharing among qdiscs, there is a need for common object that would hold the chains. This introduces such object and calls it "tcf_block". Helpers to get and put the blocks are provided to be called from individual qdisc code. Also, the original filter_list pointers are left in qdisc privs to allow the entry into tcf_block processing without any added overhead of possible multiple pointer dereference on fast path. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: move tc_classify function to cls_api.cJiri Pirko
Move tc_classify function to cls_api.c where it belongs, rename it to fit the namespace. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-12net: sched: make default fifo qdiscs appear in the dumpJiri Kosina
The original reason [1] for having hidden qdiscs (potential scalability issues in qdisc_match_from_root() with single linked list in case of large amount of qdiscs) has been invalidated by 59cc1f61f0 ("net: sched: convert qdisc linked list to hashtable"). This allows us for bringing more clarity and determinism into the dump by making default pfifo qdiscs visible. We're not turning this on by default though, at it was deemed [2] too intrusive / unnecessary change of default behavior towards userspace. Instead, TCA_DUMP_INVISIBLE netlink attribute is introduced, which allows applications to request complete qdisc hierarchy dump, including the ones that have always been implicit/invisible. Singleton noop_qdisc stays invisible, as teaching the whole infrastructure about singletons would require quite some surgery with very little gain (seeing no qdisc or seeing noop qdisc in the dump is probably setting the same user expectation). [1] http://lkml.kernel.org/r/1460732328.10638.74.camel@edumazet-glaptop3.roam.corp.google.com [2] http://lkml.kernel.org/r/20161021.105935.1907696543877061916.davem@davemloft.net Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_apiJiri Pirko
Creation is done in this file, move destruction to be at the same place. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25net_sched: drop packets after root qdisc lock is releasedEric Dumazet
Qdisc performance suffers when packets are dropped at enqueue() time because drops (kfree_skb()) are done while qdisc lock is held, delaying a dequeue() draining the queue. Nominal throughput can be reduced by 50 % when this happens, at a time we would like the dequeue() to proceed as fast as possible. Even FQ is vulnerable to this problem, while one of FQ goals was to provide some flow isolation. This patch adds a 'struct sk_buff **to_free' parameter to all qdisc->enqueue(), and in qdisc_drop() helper. I measured a performance increase of up to 12 %, but this patch is a prereq so that future batches in enqueue() can fly. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08sched: remove qdisc->dropFlorian Westphal
after removal of TCA_CBQ_OVL_STRATEGY from cbq scheduler, there are no more callers of ->drop() outside of other ->drop functions, i.e. nothing calls them. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07net: sched: do not acquire qdisc spinlock in qdisc/class stats dumpEric Dumazet
Large tc dumps (tc -s {qdisc|class} sh dev ethX) done by Google BwE host agent [1] are problematic at scale : For each qdisc/class found in the dump, we currently lock the root qdisc spinlock in order to get stats. Sampling stats every 5 seconds from thousands of HTB classes is a challenge when the root qdisc spinlock is under high pressure. Not only the dumps take time, they also slow down the fast path (queue/dequeue packets) by 10 % to 20 % in some cases. An audit of existing qdiscs showed that sch_fq_codel is the only qdisc that might need the qdisc lock in fq_codel_dump_stats() and fq_codel_dump_class_stats() In v2 of this patch, I now use the Qdisc running seqcount to provide consistent reads of packets/bytes counters, regardless of 32/64 bit arches. I also changed rate estimators to use the same infrastructure so that they no longer need to lock root qdisc lock. [1] http://static.googleusercontent.com/media/research.google.com/en//pubs/archive/43838.pdf Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Kevin Athey <kda@google.com> Cc: Xiaotian Pei <xiaotian@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-29net_sched: update hierarchical backlog tooWANG Cong
When the bottom qdisc decides to, for example, drop some packet, it calls qdisc_tree_decrease_qlen() to update the queue length for all its ancestors, we need to update the backlog too to keep the stats on root qdisc accurate. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-29net_sched: introduce qdisc_replace() helperWANG Cong
Remove nearly duplicated code and prepare for the following patch. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27net: sched: consolidate tc_classify{,_compat}Daniel Borkmann
For classifiers getting invoked via tc_classify(), we always need an extra function call into tc_classify_compat(), as both are being exported as symbols and tc_classify() itself doesn't do much except handling of reclassifications when tp->classify() returned with TC_ACT_RECLASSIFY. CBQ and ATM are the only qdiscs that directly call into tc_classify_compat(), all others use tc_classify(). When tc actions are being configured out in the kernel, tc_classify() effectively does nothing besides delegating. We could spare this layer and consolidate both functions. pktgen on single CPU constantly pushing skbs directly into the netif_receive_skb() path with a dummy classifier on ingress qdisc attached, improves slightly from 22.3Mpps to 23.1Mpps. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: enable per cpu qstatsJohn Fastabend
After previous patches to simplify qstats the qstats can be made per cpu with a packed union in Qdisc struct. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: restrict use of qstats qlenJohn Fastabend
This removes the use of qstats->qlen variable from the classifiers and makes it an explicit argument to gnet_stats_copy_queue(). The qlen represents the qdisc queue length and is packed into the qstats at the last moment before passnig to user space. By handling it explicitely we avoid, in the percpu stats case, having to figure out which per_cpu variable to put it in. It would probably be best to remove it from qstats completely but qstats is a user space ABI and can't be broken. A future patch could make an internal only qstats structure that would avoid having to allocate an additional u32 variable on the Qdisc struct. This would make the qstats struct 128bits instead of 128+32. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: implement qstat helper routinesJohn Fastabend
This adds helpers to manipulate qstats logic and replaces locations that touch the counters directly. This simplifies future patches to push qstats onto per cpu counters. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: make bstats per cpu and estimator RCU safeJohn Fastabend
In order to run qdisc's without locking statistics and estimators need to be handled correctly. To resolve bstats make the statistics per cpu. And because this is only needed for qdiscs that are running without locks which is not the case for most qdiscs in the near future only create percpu stats when qdiscs set the TCQ_F_CPUSTATS flag. Next because estimators use the bstats to calculate packets per second and bytes per second the estimator code paths are updated to use the per cpu statistics. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13net: rcu-ify tcf_protoJohn Fastabend
rcu'ify tcf_proto this allows calling tc_classify() without holding any locks. Updaters are protected by RTNL. This patch prepares the core net_sched infrastracture for running the classifier/action chains without holding the qdisc lock however it does nothing to ensure cls_xxx and act_xxx types also work without locking. Additional patches are required to address the fall out. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06net/*: Fix FSF address in file headersJeff Kirsher
Several files refer to an old address for the Free Software Foundation in the file header comment. Resolve by replacing the address with the URL <http://www.gnu.org/licenses/> so that we do not have to keep updating the header comments anytime the address changes. CC: John Fastabend <john.r.fastabend@intel.com> CC: Alex Duyck <alexander.h.duyck@intel.com> CC: Marcel Holtmann <marcel@holtmann.org> CC: Gustavo Padovan <gustavo@padovan.org> CC: Johan Hedberg <johan.hedberg@gmail.com> CC: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-01pkt_sched: Stop using NLA_PUT*().David S. Miller
These macros contain a hidden goto, and are thus extremely error prone and make code hard to audit. Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-29net: Add queue state xoff flag for stackTom Herbert
Create separate queue state flags so that either the stack or drivers can turn on XOFF. Added a set of functions used in the stack to determine if a queue is really stopped (either by stack or driver) Signed-off-by: Tom Herbert <therbert@google.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-24Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: net/sched/sch_hfsc.c net/sched/sch_htb.c net/sched/sch_tbf.c
2011-01-20net_sched: accurate bytes/packets stats/ratesEric Dumazet
In commit 44b8288308ac9d (net_sched: pfifo_head_drop problem), we fixed a problem with pfifo_head drops that incorrectly decreased sch->bstats.bytes and sch->bstats.packets Several qdiscs (CHOKe, SFQ, pfifo_head, ...) are able to drop a previously enqueued packet, and bstats cannot be changed, so bstats/rates are not accurate (over estimated) This patch changes the qdisc_bstats updates to be done at dequeue() time instead of enqueue() time. bstats counters no longer account for dropped frames, and rates are more correct, since enqueue() bursts dont have effect on dequeue() rate. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-19net_sched: cleanupsEric Dumazet
Cleanup net/sched code to current CodingStyle and practices. Reduce inline abuse Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-10net_sched: factorize qdisc stats handlingEric Dumazet
HTB takes into account skb is segmented in stats updates. Generalize this to all schedulers. They should use qdisc_bstats_update() helper instead of manipulating bstats.bytes and bstats.packets Add bstats_update() helper too for classes that use gnet_stats_basic_packed fields. Note : Right now, TCQ_F_CAN_BYPASS shortcurt can be taken only if no stab is setup on qdisc. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-21net_sched: remove the unused parameter of qdisc_create_dflt()Changli Gao
The first parameter dev isn't in use in qdisc_create_dflt(). Signed-off-by: Changli Gao <xiaosuo@gmail.com> Acked-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-17net: Remove unnecessary returns from void function()sJoe Perches
This patch removes from net/ (but not any netfilter files) all the unnecessary return; statements that precede the last closing brace of void functions. It does not remove the returns that are immediately preceded by a label as gcc doesn't like that. Done via: $ grep -rP --include=*.[ch] -l "return;\n}" net/ | \ xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }' Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-09-17pkt_sched: Fix qstats.qlen updating in dump_statsJarek Poplawski
Some classful qdiscs miss qstats.qlen updating with q.qlen of their child qdiscs in dump_stats methods. Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06net_sched: remove some unnecessary checks in classful schedulersPatrick McHardy
The class argument to the ->graft(), ->leaf(), ->dump(), ->dump_stats() all originate from either ->get() or ->walk() and are always valid. Remove unnecessary checks. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-06net_sched: make cls_ops->change and cls_ops->delete optionalPatrick McHardy
Some schedulers don't support creating, changing or deleting classes. Make the respective callbacks optionally and consistently return -EOPNOTSUPP for unsupported operations, instead of currently either -EOPNOTSUPP, -ENOSYS or no error. In case of sch_prio and sch_multiq, the removed operations additionally checked for an invalid class. This is not necessary since the class argument can only orginate from ->get() or in case of ->change is 0 for creation of new classes, in which case ->change() incorrectly returned -ENOENT. As a side-effect, this patch fixes a possible (root-only) NULL pointer function call in sch_ingress, which didn't implement a so far mandatory ->delete() operation. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>