From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ... --- .../translations/zh_CN/dev-tools/gcov.rst | 264 +++++++++++++++++++++ 1 file changed, 264 insertions(+) create mode 100644 Documentation/translations/zh_CN/dev-tools/gcov.rst (limited to 'Documentation/translations/zh_CN/dev-tools/gcov.rst') diff --git a/Documentation/translations/zh_CN/dev-tools/gcov.rst b/Documentation/translations/zh_CN/dev-tools/gcov.rst new file mode 100644 index 000000000..3158c9da1 --- /dev/null +++ b/Documentation/translations/zh_CN/dev-tools/gcov.rst @@ -0,0 +1,264 @@ +.. include:: ../disclaimer-zh_CN.rst + +:Original: Documentation/dev-tools/gcov.rst +:Translator: 赵军奎 Bernard Zhao + +在Linux内核里使用gcov做代码覆盖率检查 +===================================== + +gcov分析核心支持在Linux内核中启用GCC的覆盖率测试工具 gcov_ ，Linux内核 +运行时的代码覆盖率数据会以gcov兼容的格式导出到“gcov”debugfs目录中，可 +以通过gcov的 ``-o`` 选项（如下示例）获得指定文件的代码运行覆盖率统计数据 +（需要跳转到内核编译路径下并且要有root权限）:: + + # cd /tmp/linux-out + # gcov -o /sys/kernel/debug/gcov/tmp/linux-out/kernel spinlock.c + +这将在当前目录中创建带有执行计数注释的源代码文件。 +在获得这些统计文件后，可以使用图形化的gcov前端工具（比如 lcov_ ），来实现 +自动化处理Linux内核的覆盖率运行数据，同时生成易于阅读的HTML格式文件。 + +可能的用途: + +* 调试（用来判断每一行的代码是否已经运行过） +* 测试改进（如何修改测试代码，尽可能地覆盖到没有运行过的代码） +* 内核最小化配置（对于某一个选项配置，如果关联的代码从来没有运行过， + 是否还需要这个配置） + +.. _gcov: https://gcc.gnu.org/onlinedocs/gcc/Gcov.html +.. _lcov: http://ltp.sourceforge.net/coverage/lcov.php + + +准备 +---- + +内核打开如下配置:: + + CONFIG_DEBUG_FS=y + CONFIG_GCOV_KERNEL=y + +获取整个内核的覆盖率数据，还需要打开:: + + CONFIG_GCOV_PROFILE_ALL=y + +需要注意的是，整个内核开启覆盖率统计会造成内核镜像文件尺寸的增大， +同时内核运行也会变慢一些。 +另外，并不是所有的架构都支持整个内核开启覆盖率统计。 + +代码运行覆盖率数据只在debugfs挂载完成后才可以访问:: + + mount -t debugfs none /sys/kernel/debug + + +定制化 +------ + +如果要单独针对某一个路径或者文件进行代码覆盖率统计，可以在内核相应路 +径的Makefile中增加如下的配置: + +- 单独统计单个文件（例如main.o）:: + + GCOV_PROFILE_main.o := y + +- 单独统计某一个路径:: + + GCOV_PROFILE := y + +如果要在整个内核的覆盖率统计（开启CONFIG_GCOV_PROFILE_ALL）中单独排除 +某一个文件或者路径，可以使用如下的方法:: + + GCOV_PROFILE_main.o := n + +和:: + + GCOV_PROFILE := n + +此机制仅支持链接到内核镜像或编译为内核模块的文件。 + + +相关文件 +-------- + +gcov功能需要在debugfs中创建如下文件: + +``/sys/kernel/debug/gcov`` + gcov相关功能的根路径 + +``/sys/kernel/debug/gcov/reset`` + 全局复位文件:向该文件写入数据后会将所有的gcov统计数据清0 + +``/sys/kernel/debug/gcov/path/to/compile/dir/file.gcda`` + gcov工具可以识别的覆盖率统计数据文件，向该文件写入数据后 + 会将本文件的gcov统计数据清0 + +``/sys/kernel/debug/gcov/path/to/compile/dir/file.gcno`` + gcov工具需要的软连接文件（指向编译时生成的信息统计文件），这个文件是 + 在gcc编译时如果配置了选项 ``-ftest-coverage`` 时生成的。 + + +针对模块的统计 +-------------- + +内核中的模块会动态的加载和卸载，模块卸载时对应的数据会被清除掉。 +gcov提供了一种机制，通过保留相关数据的副本来收集这部分卸载模块的覆盖率数据。 +模块卸载后这些备份数据在debugfs中会继续存在。 +一旦这个模块重新加载，模块关联的运行统计会被初始化成debugfs中备份的数据。 + +可以通过对内核参数gcov_persist的修改来停用gcov对模块的备份机制:: + + gcov_persist = 0 + +在运行时，用户还可以通过写入模块的数据文件或者写入gcov复位文件来丢弃已卸 +载模块的数据。 + + +编译机和测试机分离 +------------------ + +gcov的内核分析插桩支持内核的编译和运行是在同一台机器上，也可以编译和运 +行是在不同的机器上。 +如果内核编译和运行是不同的机器，那么需要额外的准备工作，这取决于gcov工具 +是在哪里使用的: + +.. _gcov-test_zh: + +a) 若gcov运行在测试机上 + + 测试机上面gcov工具的版本必须要跟内核编译机器使用的gcc版本相兼容， + 同时下面的文件要从编译机拷贝到测试机上: + + 从源代码中: + - 所有的C文件和头文件 + + 从编译目录中: + - 所有的C文件和头文件 + - 所有的.gcda文件和.gcno文件 + - 所有目录的链接 + + 特别需要注意，测试机器上面的目录结构跟编译机器上面的目录机构必须 + 完全一致。 + 如果文件是软链接，需要替换成真正的目录文件（这是由make的当前工作 + 目录变量CURDIR引起的）。 + +.. _gcov-build_zh: + +b) 若gcov运行在编译机上 + + 测试用例运行结束后，如下的文件需要从测试机中拷贝到编译机上: + + 从sysfs中的gcov目录中: + - 所有的.gcda文件 + - 所有的.gcno文件软链接 + + 这些文件可以拷贝到编译机的任意目录下，gcov使用-o选项指定拷贝的 + 目录。 + + 比如一个是示例的目录结构如下:: + + /tmp/linux: 内核源码目录 + /tmp/out: 内核编译文件路径（make O=指定） + /tmp/coverage: 从测试机器上面拷贝的数据文件路径 + + [user@build] cd /tmp/out + [user@build] gcov -o /tmp/coverage/tmp/out/init main.c + + +关于编译器的注意事项 +-------------------- + +GCC和LLVM gcov工具不一定兼容。 +如果编译器是GCC，使用 gcov_ 来处理.gcno和.gcda文件，如果是Clang编译器， +则使用 llvm-cov_ 。 + +.. _gcov: https://gcc.gnu.org/onlinedocs/gcc/Gcov.html +.. _llvm-cov: https://llvm.org/docs/CommandGuide/llvm-cov.html + +GCC和Clang gcov之间的版本差异由Kconfig处理的。 +kconfig会根据编译工具链的检查自动选择合适的gcov格式。 + +问题定位 +-------- + +可能出现的问题1 + 编译到链接阶段报错终止 + +问题原因 + 分析标志指定在了源文件但是没有链接到主内核，或者客制化了链接程序 + +解决方法 + 通过在相应的Makefile中使用 ``GCOV_PROFILE := n`` + 或者 ``GCOV_PROFILE_basename.o := n`` 来将链接报错的文件排除掉 + +可能出现的问题2 + 从sysfs复制的文件显示为空或不完整 + +问题原因 + 由于seq_file的工作方式，某些工具（例如cp或tar）可能无法正确地从 + sysfs复制文件。 + +解决方法 + 使用 ``cat`` 读取 ``.gcda`` 文件，使用 ``cp -d`` 复制链接，或者使用附录B + 中所示的机制。 + + +附录A：collect_on_build.sh +-------------------------- + +用于在编译机上收集覆盖率元文件的示例脚本 +（见 :ref:`编译机和测试机分离 a. ` ） + +.. code-block:: sh + + #!/bin/bash + + KSRC=$1 + KOBJ=$2 + DEST=$3 + + if [ -z "$KSRC" ] || [ -z "$KOBJ" ] || [ -z "$DEST" ]; then + echo "Usage: $0 " >&2 + exit 1 + fi + + KSRC=$(cd $KSRC; printf "all:\n\t@echo \${CURDIR}\n" | make -f -) + KOBJ=$(cd $KOBJ; printf "all:\n\t@echo \${CURDIR}\n" | make -f -) + + find $KSRC $KOBJ \( -name '*.gcno' -o -name '*.[ch]' -o -type l \) -a \ + -perm /u+r,g+r | tar cfz $DEST -P -T - + + if [ $? -eq 0 ] ; then + echo "$DEST successfully created, copy to test system and unpack with:" + echo " tar xfz $DEST -P" + else + echo "Could not create file $DEST" + fi + + +附录B：collect_on_test.sh +------------------------- + +用于在测试机上收集覆盖率数据文件的示例脚本 +（见 :ref:`编译机和测试机分离 b. ` ） + +.. code-block:: sh + + #!/bin/bash -e + + DEST=$1 + GCDA=/sys/kernel/debug/gcov + + if [ -z "$DEST" ] ; then + echo "Usage: $0 " >&2 + exit 1 + fi + + TEMPDIR=$(mktemp -d) + echo Collecting data.. + find $GCDA -type d -exec mkdir -p $TEMPDIR/\{\} \; + find $GCDA -name '*.gcda' -exec sh -c 'cat < $0 > '$TEMPDIR'/$0' {} \; + find $GCDA -name '*.gcno' -exec sh -c 'cp -d $0 '$TEMPDIR'/$0' {} \; + tar czf $DEST -C $TEMPDIR sys + rm -rf $TEMPDIR + + echo "$DEST successfully created, copy to build system and unpack with:" + echo " tar xfz $DEST" -- cgit v1.2.3