kernel/git/stable/linux.git/net/sched/sch_atm.c, branch master

net/sched: Retire ATM qdisc

2023-02-16T08:27:06+00:00

The ATM qdisc has served us well over the years but has not been getting much TLC due to lack of known users. Most recently it has become a shooting target for syzkaller. For this reason, we are retiring it. Signed-off-by: Jamal Hadi Salim Acked-by: Jiri Pirko Signed-off-by: Paolo Abeni

net: sched: atm: dont intepret cls results when asked to drop

2023-01-02T13:32:43+00:00

If asked to drop a packet via TC_ACT_SHOT it is unsafe to assume res.class contains a valid pointer Fixes: b0188d4dbe5f ("[NET_SCHED]: sch_atm: Lindent") Signed-off-by: Jamal Hadi Salim Signed-off-by: David S. Miller

net/sched: use tc_qdisc_stats_dump() in qdisc

2022-09-23T00:34:10+00:00

use tc_qdisc_stats_dump() in qdisc. Signed-off-by: Zhengchao Shao Reviewed-by: Victor Nogueira Tested-by: Victor Nogueira Acked-by: Toke Høiland-Jørgensen Signed-off-by: Jakub Kicinski

net: sched: delete duplicate cleanup of backlog and qlen

2022-08-25T13:10:17+00:00

qdisc_reset() is clearing qdisc->q.qlen and qdisc->qstats.backlog _after_ calling qdisc->ops->reset. There is no need to clear them again in the specific reset function. Signed-off-by: Zhengchao Shao Link: https://lore.kernel.org/r/20220824005231.345727-1-shaozhengchao@huawei.com Signed-off-by: Paolo Abeni

net: sched: Remove Qdisc::running sequence counter

2021-10-18T11:54:41+00:00

The Qdisc::running sequence counter has two uses: 1. Reliably reading qdisc's tc statistics while the qdisc is running (a seqcount read/retry loop at gnet_stats_add_basic()). 2. As a flag, indicating whether the qdisc in question is running (without any retry loops). For the first usage, the Qdisc::running sequence counter write section, qdisc_run_begin() => qdisc_run_end(), covers a much wider area than what is actually needed: the raw qdisc's bstats update. A u64_stats sync point was thus introduced (in previous commits) inside the bstats structure itself. A local u64_stats write section is then started and stopped for the bstats updates. Use that u64_stats sync point mechanism for the bstats read/retry loop at gnet_stats_add_basic(). For the second qdisc->running usage, a __QDISC_STATE_RUNNING bit flag, accessed with atomic bitops, is sufficient. Using a bit flag instead of a sequence counter at qdisc_run_begin/end() and qdisc_is_running() leads to the SMP barriers implicitly added through raw_read_seqcount() and write_seqcount_begin/end() getting removed. All call sites have been surveyed though, and no required ordering was identified. Now that the qdisc->running sequence counter is no longer used, remove it. Note, using u64_stats implies no sequence counter protection for 64-bit architectures. This can lead to the qdisc tc statistics "packets" vs. "bytes" values getting out of sync on rare occasions. The individual values will still be valid. Signed-off-by: Ahmed S. Darwish Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: David S. Miller

net: sched: Merge Qdisc::bstats and Qdisc::cpu_bstats data types

2021-10-18T11:54:41+00:00

The only factor differentiating per-CPU bstats data type (struct gnet_stats_basic_cpu) from the packed non-per-CPU one (struct gnet_stats_basic_packed) was a u64_stats sync point inside the former. The two data types are now equivalent: earlier commits added a u64_stats sync point to the latter. Combine both data types into "struct gnet_stats_basic_sync". This eliminates redundancy and simplifies the bstats read/write APIs. Use u64_stats_t for bstats "packets" and "bytes" data types. On 64-bit architectures, u64_stats sync points do not use sequence counter protection. Signed-off-by: Ahmed S. Darwish Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: David S. Miller

net: sched: Protect Qdisc::bstats with u64_stats

2021-10-18T11:54:41+00:00

The not-per-CPU variant of qdisc tc (traffic control) statistics, Qdisc::gnet_stats_basic_packed bstats, is protected with Qdisc::running sequence counter. This sequence counter is used for reliably protecting bstats reads from parallel writes. Meanwhile, the seqcount's write section covers a much wider area than bstats update: qdisc_run_begin() => qdisc_run_end(). That read/write section asymmetry can lead to needless retries of the read section. To prepare for removing the Qdisc::running sequence counter altogether, introduce a u64_stats sync point inside bstats instead. Modify _bstats_update() to start/end the bstats u64_stats write section. For bisectability, and finer commits granularity, the bstats read section is still protected with a Qdisc::running read/retry loop and qdisc_run_begin/end() still starts/ends that seqcount write section. Once all call sites are modified to use _bstats_update(), the Qdisc::running seqcount will be removed and bstats read/retry loop will be modified to utilize the internal u64_stats sync point. Note, using u64_stats implies no sequence counter protection for 64-bit architectures. This can lead to the statistics "packets" vs. "bytes" values getting out of sync on rare occasions. The individual values will still be valid. [bigeasy: Minor commit message edits, init all gnet_stats_basic_packed.] Signed-off-by: Ahmed S. Darwish Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: David S. Miller

net/sched: store the last executed chain also for clsact egress

2021-07-29T21:17:37+00:00

currently, only 'ingress' and 'clsact ingress' qdiscs store the tc 'chain id' in the skb extension. However, userspace programs (like ovs) are able to setup egress rules, and datapath gets confused in case it doesn't find the 'chain id' for a packet that's "recirculated" by tc. Change tcf_classify() to have the same semantic as tcf_classify_ingress() so that a single function can be called in ingress / egress, using the tc ingress / egress block respectively. Suggested-by: Alaa Hleilel Signed-off-by: Davide Caratti Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

net: sched: Add extack to Qdisc_class_ops.delete

2021-01-23T04:41:29+00:00

In a following commit, sch_htb will start using extack in the delete class operation to pass hardware errors in offload mode. This commit prepares for that by adding the extack parameter to this callback and converting usage of the existing qdiscs. Signed-off-by: Maxim Mikityanskiy Reviewed-by: Tariq Toukan Signed-off-by: Jakub Kicinski

net: sched: convert tasklets to use new tasklet_setup() API

2020-11-07T18:41:15+00:00

In preparation for unconditionally passing the struct tasklet_struct pointer to all tasklet callbacks, switch to using the new tasklet_setup() and from_tasklet() to pass the tasklet pointer explicitly. Signed-off-by: Romain Perier Signed-off-by: Allen Pais Signed-off-by: Jakub Kicinski