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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /tools/perf/Documentation/perf-trace.txt | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
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().
...
Diffstat (limited to 'tools/perf/Documentation/perf-trace.txt')
-rw-r--r-- | tools/perf/Documentation/perf-trace.txt | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf-trace.txt b/tools/perf/Documentation/perf-trace.txt new file mode 100644 index 000000000..f0da8cf63 --- /dev/null +++ b/tools/perf/Documentation/perf-trace.txt @@ -0,0 +1,347 @@ +perf-trace(1) +============= + +NAME +---- +perf-trace - strace inspired tool + +SYNOPSIS +-------- +[verse] +'perf trace' +'perf trace record' + +DESCRIPTION +----------- +This command will show the events associated with the target, initially +syscalls, but other system events like pagefaults, task lifetime events, +scheduling events, etc. + +This is a live mode tool in addition to working with perf.data files like +the other perf tools. Files can be generated using the 'perf record' command +but the session needs to include the raw_syscalls events (-e 'raw_syscalls:*'). +Alternatively, 'perf trace record' can be used as a shortcut to +automatically include the raw_syscalls events when writing events to a file. + +The following options apply to perf trace; options to perf trace record are +found in the perf record man page. + +OPTIONS +------- + +-a:: +--all-cpus:: + System-wide collection from all CPUs. + +-e:: +--expr:: +--event:: + List of syscalls and other perf events (tracepoints, HW cache events, + etc) to show. Globbing is supported, e.g.: "epoll_*", "*msg*", etc. + See 'perf list' for a complete list of events. + Prefixing with ! shows all syscalls but the ones specified. You may + need to escape it. + +--filter=<filter>:: + Event filter. This option should follow an event selector (-e) which + selects tracepoint event(s). + + +-D msecs:: +--delay msecs:: +After starting the program, wait msecs before measuring. This is useful to +filter out the startup phase of the program, which is often very different. + +-o:: +--output=:: + Output file name. + +-p:: +--pid=:: + Record events on existing process ID (comma separated list). + +-t:: +--tid=:: + Record events on existing thread ID (comma separated list). + +-u:: +--uid=:: + Record events in threads owned by uid. Name or number. + +-G:: +--cgroup:: + Record events in threads in a cgroup. + + Look for cgroups to set at the /sys/fs/cgroup/perf_event directory, then + remove the /sys/fs/cgroup/perf_event/ part and try: + + perf trace -G A -e sched:*switch + + Will set all raw_syscalls:sys_{enter,exit}, pgfault, vfs_getname, etc + _and_ sched:sched_switch to the 'A' cgroup, while: + + perf trace -e sched:*switch -G A + + will only set the sched:sched_switch event to the 'A' cgroup, all the + other events (raw_syscalls:sys_{enter,exit}, etc are left "without" + a cgroup (on the root cgroup, sys wide, etc). + + Multiple cgroups: + + perf trace -G A -e sched:*switch -G B + + the syscall ones go to the 'A' cgroup, the sched:sched_switch goes + to the 'B' cgroup. + +--filter-pids=:: + Filter out events for these pids and for 'trace' itself (comma separated list). + +-v:: +--verbose:: + Increase the verbosity level. + +--no-inherit:: + Child tasks do not inherit counters. + +-m:: +--mmap-pages=:: + Number of mmap data pages (must be a power of two) or size + specification with appended unit character - B/K/M/G. The + size is rounded up to have nearest pages power of two value. + +-C:: +--cpu:: +Collect samples only on the list of CPUs provided. Multiple CPUs can be provided as a +comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2. +In per-thread mode with inheritance mode on (default), Events are captured only when +the thread executes on the designated CPUs. Default is to monitor all CPUs. + +--duration:: + Show only events that had a duration greater than N.M ms. + +--sched:: + Accrue thread runtime and provide a summary at the end of the session. + +--failure:: + Show only syscalls that failed, i.e. that returned < 0. + +-i:: +--input:: + Process events from a given perf data file. + +-T:: +--time:: + Print full timestamp rather time relative to first sample. + +--comm:: + Show process COMM right beside its ID, on by default, disable with --no-comm. + +-s:: +--summary:: + Show only a summary of syscalls by thread with min, max, and average times + (in msec) and relative stddev. + +-S:: +--with-summary:: + Show all syscalls followed by a summary by thread with min, max, and + average times (in msec) and relative stddev. + +--errno-summary:: + To be used with -s or -S, to show stats for the errnos experienced by + syscalls, using only this option will trigger --summary. + +--tool_stats:: + Show tool stats such as number of times fd->pathname was discovered thru + hooking the open syscall return + vfs_getname or via reading /proc/pid/fd, etc. + +-f:: +--force:: + Don't complain, do it. + +-F=[all|min|maj]:: +--pf=[all|min|maj]:: + Trace pagefaults. Optionally, you can specify whether you want minor, + major or all pagefaults. Default value is maj. + +--syscalls:: + Trace system calls. This options is enabled by default, disable with + --no-syscalls. + +--call-graph [mode,type,min[,limit],order[,key][,branch]]:: + Setup and enable call-graph (stack chain/backtrace) recording. + See `--call-graph` section in perf-record and perf-report + man pages for details. The ones that are most useful in 'perf trace' + are 'dwarf' and 'lbr', where available, try: 'perf trace --call-graph dwarf'. + + Using this will, for the root user, bump the value of --mmap-pages to 4 + times the maximum for non-root users, based on the kernel.perf_event_mlock_kb + sysctl. This is done only if the user doesn't specify a --mmap-pages value. + +--kernel-syscall-graph:: + Show the kernel callchains on the syscall exit path. + +--max-events=N:: + Stop after processing N events. Note that strace-like events are considered + only at exit time or when a syscall is interrupted, i.e. in those cases this + option is equivalent to the number of lines printed. + +--switch-on EVENT_NAME:: + Only consider events after this event is found. + +--switch-off EVENT_NAME:: + Stop considering events after this event is found. + +--show-on-off-events:: + Show the --switch-on/off events too. + +--max-stack:: + Set the stack depth limit when parsing the callchain, anything + beyond the specified depth will be ignored. Note that at this point + this is just about the presentation part, i.e. the kernel is still + not limiting, the overhead of callchains needs to be set via the + knobs in --call-graph dwarf. + + Implies '--call-graph dwarf' when --call-graph not present on the + command line, on systems where DWARF unwinding was built in. + + Default: /proc/sys/kernel/perf_event_max_stack when present for + live sessions (without --input/-i), 127 otherwise. + +--min-stack:: + Set the stack depth limit when parsing the callchain, anything + below the specified depth will be ignored. Disabled by default. + + Implies '--call-graph dwarf' when --call-graph not present on the + command line, on systems where DWARF unwinding was built in. + +--print-sample:: + Print the PERF_RECORD_SAMPLE PERF_SAMPLE_ info for the + raw_syscalls:sys_{enter,exit} tracepoints, for debugging. + +--proc-map-timeout:: + When processing pre-existing threads /proc/XXX/mmap, it may take a long time, + because the file may be huge. A time out is needed in such cases. + This option sets the time out limit. The default value is 500 ms. + +--sort-events:: + Do sorting on batches of events, use when noticing out of order events that + may happen, for instance, when a thread gets migrated to a different CPU + while processing a syscall. + +--libtraceevent_print:: + Use libtraceevent to print tracepoint arguments. By default 'perf trace' uses + the same beautifiers used in the strace-like enter+exit lines to augment the + tracepoint arguments. + +--map-dump:: + Dump BPF maps setup by events passed via -e, for instance the augmented_raw_syscalls + living in tools/perf/examples/bpf/augmented_raw_syscalls.c. For now this + dumps just boolean map values and integer keys, in time this will print in hex + by default and use BTF when available, as well as use functions to do pretty + printing using the existing 'perf trace' syscall arg beautifiers to map integer + arguments to strings (pid to comm, syscall id to syscall name, etc). + + +PAGEFAULTS +---------- + +When tracing pagefaults, the format of the trace is as follows: + +<min|maj>fault [<ip.symbol>+<ip.offset>] => <addr.dso@addr.offset> (<map type><addr level>). + +- min/maj indicates whether fault event is minor or major; +- ip.symbol shows symbol for instruction pointer (the code that generated the + fault); if no debug symbols available, perf trace will print raw IP; +- addr.dso shows DSO for the faulted address; +- map type is either 'd' for non-executable maps or 'x' for executable maps; +- addr level is either 'k' for kernel dso or '.' for user dso. + +For symbols resolution you may need to install debugging symbols. + +Please be aware that duration is currently always 0 and doesn't reflect actual +time it took for fault to be handled! + +When --verbose specified, perf trace tries to print all available information +for both IP and fault address in the form of dso@symbol+offset. + +EXAMPLES +-------- + +Trace only major pagefaults: + + $ perf trace --no-syscalls -F + +Trace syscalls, major and minor pagefaults: + + $ perf trace -F all + + 1416.547 ( 0.000 ms): python/20235 majfault [CRYPTO_push_info_+0x0] => /lib/x86_64-linux-gnu/libcrypto.so.1.0.0@0x61be0 (x.) + + As you can see, there was major pagefault in python process, from + CRYPTO_push_info_ routine which faulted somewhere in libcrypto.so. + +Trace the first 4 open, openat or open_by_handle_at syscalls (in the future more syscalls may match here): + + $ perf trace -e open* --max-events 4 + [root@jouet perf]# trace -e open* --max-events 4 + 2272.992 ( 0.037 ms): gnome-shell/1370 openat(dfd: CWD, filename: /proc/self/stat) = 31 + 2277.481 ( 0.139 ms): gnome-shell/3039 openat(dfd: CWD, filename: /proc/self/stat) = 65 + 3026.398 ( 0.076 ms): gnome-shell/3039 openat(dfd: CWD, filename: /proc/self/stat) = 65 + 4294.665 ( 0.015 ms): sed/15879 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC) = 3 + $ + +Trace the first minor page fault when running a workload: + + # perf trace -F min --max-stack=7 --max-events 1 sleep 1 + 0.000 ( 0.000 ms): sleep/18006 minfault [__clear_user+0x1a] => 0x5626efa56080 (?k) + __clear_user ([kernel.kallsyms]) + load_elf_binary ([kernel.kallsyms]) + search_binary_handler ([kernel.kallsyms]) + __do_execve_file.isra.33 ([kernel.kallsyms]) + __x64_sys_execve ([kernel.kallsyms]) + do_syscall_64 ([kernel.kallsyms]) + entry_SYSCALL_64 ([kernel.kallsyms]) + # + +Trace the next min page page fault to take place on the first CPU: + + # perf trace -F min --call-graph=dwarf --max-events 1 --cpu 0 + 0.000 ( 0.000 ms): Web Content/17136 minfault [js::gc::Chunk::fetchNextDecommittedArena+0x4b] => 0x7fbe6181b000 (?.) + js::gc::FreeSpan::initAsEmpty (inlined) + js::gc::Arena::setAsNotAllocated (inlined) + js::gc::Chunk::fetchNextDecommittedArena (/usr/lib64/firefox/libxul.so) + js::gc::Chunk::allocateArena (/usr/lib64/firefox/libxul.so) + js::gc::GCRuntime::allocateArena (/usr/lib64/firefox/libxul.so) + js::gc::ArenaLists::allocateFromArena (/usr/lib64/firefox/libxul.so) + js::gc::GCRuntime::tryNewTenuredThing<JSString, (js::AllowGC)1> (inlined) + js::AllocateString<JSString, (js::AllowGC)1> (/usr/lib64/firefox/libxul.so) + js::Allocate<JSThinInlineString, (js::AllowGC)1> (inlined) + JSThinInlineString::new_<(js::AllowGC)1> (inlined) + AllocateInlineString<(js::AllowGC)1, unsigned char> (inlined) + js::ConcatStrings<(js::AllowGC)1> (/usr/lib64/firefox/libxul.so) + [0x18b26e6bc2bd] (/tmp/perf-17136.map) + # + +Trace the next two sched:sched_switch events, four block:*_plug events, the +next block:*_unplug and the next three net:*dev_queue events, this last one +with a backtrace of at most 16 entries, system wide: + + # perf trace -e sched:*switch/nr=2/,block:*_plug/nr=4/,block:*_unplug/nr=1/,net:*dev_queue/nr=3,max-stack=16/ + 0.000 :0/0 sched:sched_switch:swapper/2:0 [120] S ==> rcu_sched:10 [120] + 0.015 rcu_sched/10 sched:sched_switch:rcu_sched:10 [120] R ==> swapper/2:0 [120] + 254.198 irq/50-iwlwifi/680 net:net_dev_queue:dev=wlp3s0 skbaddr=0xffff93498051f600 len=66 + __dev_queue_xmit ([kernel.kallsyms]) + 273.977 :0/0 net:net_dev_queue:dev=wlp3s0 skbaddr=0xffff93498051f600 len=78 + __dev_queue_xmit ([kernel.kallsyms]) + 274.007 :0/0 net:net_dev_queue:dev=wlp3s0 skbaddr=0xffff93498051ff00 len=78 + __dev_queue_xmit ([kernel.kallsyms]) + 2930.140 kworker/u16:58/2722 block:block_plug:[kworker/u16:58] + 2930.162 kworker/u16:58/2722 block:block_unplug:[kworker/u16:58] 1 + 4466.094 jbd2/dm-2-8/748 block:block_plug:[jbd2/dm-2-8] + 8050.123 kworker/u16:30/2694 block:block_plug:[kworker/u16:30] + 8050.271 kworker/u16:30/2694 block:block_plug:[kworker/u16:30] + # + +SEE ALSO +-------- +linkperf:perf-record[1], linkperf:perf-script[1] |