summaryrefslogtreecommitdiffstats
path: root/Documentation/networking/gen_stats.rst
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2020-06-04 01:27:18 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-04 01:27:18 +0200
commitcb8e59cc87201af93dfbb6c3dccc8fcad72a09c2 (patch)
treea334db9022f89654b777bbce8c4c6632e65b9031 /Documentation/networking/gen_stats.rst
parentMerge branch 'uaccess.comedi' of git://git.kernel.org/pub/scm/linux/kernel/gi... (diff)
parentselftests: net: ip_defrag: ignore EPERM (diff)
downloadlinux-cb8e59cc87201af93dfbb6c3dccc8fcad72a09c2.tar.xz
linux-cb8e59cc87201af93dfbb6c3dccc8fcad72a09c2.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller: 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz Augusto von Dentz. 2) Add GSO partial support to igc, from Sasha Neftin. 3) Several cleanups and improvements to r8169 from Heiner Kallweit. 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a device self-test. From Andrew Lunn. 5) Start moving away from custom driver versions, use the globally defined kernel version instead, from Leon Romanovsky. 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin. 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet. 8) Add sriov and vf support to hinic, from Luo bin. 9) Support Media Redundancy Protocol (MRP) in the bridging code, from Horatiu Vultur. 10) Support netmap in the nft_nat code, from Pablo Neira Ayuso. 11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina Dubroca. Also add ipv6 support for espintcp. 12) Lots of ReST conversions of the networking documentation, from Mauro Carvalho Chehab. 13) Support configuration of ethtool rxnfc flows in bcmgenet driver, from Doug Berger. 14) Allow to dump cgroup id and filter by it in inet_diag code, from Dmitry Yakunin. 15) Add infrastructure to export netlink attribute policies to userspace, from Johannes Berg. 16) Several optimizations to sch_fq scheduler, from Eric Dumazet. 17) Fallback to the default qdisc if qdisc init fails because otherwise a packet scheduler init failure will make a device inoperative. From Jesper Dangaard Brouer. 18) Several RISCV bpf jit optimizations, from Luke Nelson. 19) Correct the return type of the ->ndo_start_xmit() method in several drivers, it's netdev_tx_t but many drivers were using 'int'. From Yunjian Wang. 20) Add an ethtool interface for PHY master/slave config, from Oleksij Rempel. 21) Add BPF iterators, from Yonghang Song. 22) Add cable test infrastructure, including ethool interfaces, from Andrew Lunn. Marvell PHY driver is the first to support this facility. 23) Remove zero-length arrays all over, from Gustavo A. R. Silva. 24) Calculate and maintain an explicit frame size in XDP, from Jesper Dangaard Brouer. 25) Add CAP_BPF, from Alexei Starovoitov. 26) Support terse dumps in the packet scheduler, from Vlad Buslov. 27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei. 28) Add devm_register_netdev(), from Bartosz Golaszewski. 29) Minimize qdisc resets, from Cong Wang. 30) Get rid of kernel_getsockopt and kernel_setsockopt in order to eliminate set_fs/get_fs calls. From Christoph Hellwig. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits) selftests: net: ip_defrag: ignore EPERM net_failover: fixed rollback in net_failover_open() Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv" Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv" vmxnet3: allow rx flow hash ops only when rss is enabled hinic: add set_channels ethtool_ops support selftests/bpf: Add a default $(CXX) value tools/bpf: Don't use $(COMPILE.c) bpf, selftests: Use bpf_probe_read_kernel s390/bpf: Use bcr 0,%0 as tail call nop filler s390/bpf: Maintain 8-byte stack alignment selftests/bpf: Fix verifier test selftests/bpf: Fix sample_cnt shared between two threads bpf, selftests: Adapt cls_redirect to call csum_level helper bpf: Add csum_level helper for fixing up csum levels bpf: Fix up bpf_skb_adjust_room helper's skb csum setting sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf() crypto/chtls: IPv6 support for inline TLS Crypto/chcr: Fixes a coccinile check error Crypto/chcr: Fixes compilations warnings ...
Diffstat (limited to 'Documentation/networking/gen_stats.rst')
-rw-r--r--Documentation/networking/gen_stats.rst129
1 files changed, 129 insertions, 0 deletions
diff --git a/Documentation/networking/gen_stats.rst b/Documentation/networking/gen_stats.rst
new file mode 100644
index 000000000000..595a83b9a61b
--- /dev/null
+++ b/Documentation/networking/gen_stats.rst
@@ -0,0 +1,129 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===============================================
+Generic networking statistics for netlink users
+===============================================
+
+Statistic counters are grouped into structs:
+
+==================== ===================== =====================
+Struct TLV type Description
+==================== ===================== =====================
+gnet_stats_basic TCA_STATS_BASIC Basic statistics
+gnet_stats_rate_est TCA_STATS_RATE_EST Rate estimator
+gnet_stats_queue TCA_STATS_QUEUE Queue statistics
+none TCA_STATS_APP Application specific
+==================== ===================== =====================
+
+
+Collecting:
+-----------
+
+Declare the statistic structs you need::
+
+ struct mystruct {
+ struct gnet_stats_basic bstats;
+ struct gnet_stats_queue qstats;
+ ...
+ };
+
+Update statistics, in dequeue() methods only, (while owning qdisc->running)::
+
+ mystruct->tstats.packet++;
+ mystruct->qstats.backlog += skb->pkt_len;
+
+
+Export to userspace (Dump):
+---------------------------
+
+::
+
+ my_dumping_routine(struct sk_buff *skb, ...)
+ {
+ struct gnet_dump dump;
+
+ if (gnet_stats_start_copy(skb, TCA_STATS2, &mystruct->lock, &dump,
+ TCA_PAD) < 0)
+ goto rtattr_failure;
+
+ if (gnet_stats_copy_basic(&dump, &mystruct->bstats) < 0 ||
+ gnet_stats_copy_queue(&dump, &mystruct->qstats) < 0 ||
+ gnet_stats_copy_app(&dump, &xstats, sizeof(xstats)) < 0)
+ goto rtattr_failure;
+
+ if (gnet_stats_finish_copy(&dump) < 0)
+ goto rtattr_failure;
+ ...
+ }
+
+TCA_STATS/TCA_XSTATS backward compatibility:
+--------------------------------------------
+
+Prior users of struct tc_stats and xstats can maintain backward
+compatibility by calling the compat wrappers to keep providing the
+existing TLV types::
+
+ my_dumping_routine(struct sk_buff *skb, ...)
+ {
+ if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS,
+ TCA_XSTATS, &mystruct->lock, &dump,
+ TCA_PAD) < 0)
+ goto rtattr_failure;
+ ...
+ }
+
+A struct tc_stats will be filled out during gnet_stats_copy_* calls
+and appended to the skb. TCA_XSTATS is provided if gnet_stats_copy_app
+was called.
+
+
+Locking:
+--------
+
+Locks are taken before writing and released once all statistics have
+been written. Locks are always released in case of an error. You
+are responsible for making sure that the lock is initialized.
+
+
+Rate Estimator:
+---------------
+
+0) Prepare an estimator attribute. Most likely this would be in user
+ space. The value of this TLV should contain a tc_estimator structure.
+ As usual, such a TLV needs to be 32 bit aligned and therefore the
+ length needs to be appropriately set, etc. The estimator interval
+ and ewma log need to be converted to the appropriate values.
+ tc_estimator.c::tc_setup_estimator() is advisable to be used as the
+ conversion routine. It does a few clever things. It takes a time
+ interval in microsecs, a time constant also in microsecs and a struct
+ tc_estimator to be populated. The returned tc_estimator can be
+ transported to the kernel. Transfer such a structure in a TLV of type
+ TCA_RATE to your code in the kernel.
+
+In the kernel when setting up:
+
+1) make sure you have basic stats and rate stats setup first.
+2) make sure you have initialized stats lock that is used to setup such
+ stats.
+3) Now initialize a new estimator::
+
+ int ret = gen_new_estimator(my_basicstats,my_rate_est_stats,
+ mystats_lock, attr_with_tcestimator_struct);
+
+ if ret == 0
+ success
+ else
+ failed
+
+From now on, every time you dump my_rate_est_stats it will contain
+up-to-date info.
+
+Once you are done, call gen_kill_estimator(my_basicstats,
+my_rate_est_stats) Make sure that my_basicstats and my_rate_est_stats
+are still valid (i.e still exist) at the time of making this call.
+
+
+Authors:
+--------
+- Thomas Graf <tgraf@suug.ch>
+- Jamal Hadi Salim <hadi@cyberus.ca>