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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /tools/power/pm-graph/sleepgraph.8
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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/power/pm-graph/sleepgraph.8')
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+.TH SLEEPGRAPH 8
+.SH NAME
+sleepgraph \- Suspend/Resume timing analysis
+.SH SYNOPSIS
+.ft B
+.B sleepgraph
+.RB [ OPTIONS ]
+.RB [ COMMAND ]
+.SH DESCRIPTION
+\fBsleepgraph \fP is designed to assist kernel and OS developers
+in optimizing their linux stack's suspend/resume time. Using a kernel
+image built with a few extra options enabled, the tool will execute a
+suspend and capture dmesg and ftrace data until resume is complete.
+This data is transformed into a device timeline and an optional
+callgraph to give a detailed view of which devices/subsystems are
+taking the most time in suspend/resume.
+.PP
+If no specific command is given, the default behavior is to initiate
+a suspend/resume.
+.PP
+Generates output files in subdirectory: suspend-yymmdd-HHMMSS
+ html timeline : <hostname>_<mode>.html
+ raw dmesg file : <hostname>_<mode>_dmesg.txt
+ raw ftrace file : <hostname>_<mode>_ftrace.txt
+.SH OPTIONS
+.TP
+\fB-h\fR
+Print the help text.
+.TP
+\fB-v\fR
+Print the current tool version.
+.TP
+\fB-verbose\fR
+Print extra information during execution and analysis.
+.TP
+\fB-config \fIfile\fR
+Pull arguments and config options from a file.
+.TP
+\fB-m \fImode\fR
+Mode to initiate for suspend e.g. standby, freeze, mem (default: mem).
+.TP
+\fB-o \fIname\fR
+Overrides the output subdirectory name when running a new test.
+Use {date}, {time}, {hostname} for current values.
+.sp
+e.g. suspend-{hostname}-{date}-{time}
+.TP
+\fB-rtcwake \fIt\fR | off
+Use rtcwake to autoresume after \fIt\fR seconds (default: 15). Set t to "off" to
+disable rtcwake and require a user keypress to resume.
+.TP
+\fB-addlogs\fR
+Add the dmesg and ftrace logs to the html output. They will be viewable by
+clicking buttons in the timeline.
+.TP
+\fB-noturbostat\fR
+By default, if turbostat is found and the requested mode is freeze, sleepgraph
+will execute the suspend via turbostat and collect data in the timeline log.
+This option disables the use of turbostat.
+.TP
+\fB-result \fIfile\fR
+Export a results table to a text file for parsing.
+.TP
+\fB-sync\fR
+Sync the filesystems before starting the test. This reduces the size of
+the sys_sync call which happens in the suspend_prepare phase.
+.TP
+\fB-rs \fIenable/disable\fR
+During test, enable/disable runtime suspend for all devices. The test is delayed
+by 5 seconds to allow runtime suspend changes to occur. The settings are restored
+after the test is complete.
+.TP
+\fB-display \fIon/off/standby/suspend\fR
+Switch the display to the requested mode for the test using the xset command.
+This helps maintain the consistency of test data for better comparison.
+.TP
+\fB-wifi\fR
+If a wifi connection is available, check that it reconnects after resume. Include
+the reconnect time in the total resume time calculation and treat wifi timeouts
+as resume failures.
+.TP
+\fB-wifitrace\fR
+Trace through the wifi reconnect time and include it in the timeline.
+
+.SS "advanced"
+.TP
+\fB-gzip\fR
+Gzip the trace and dmesg logs to save space. The tool can also read in gzipped
+logs for processing.
+.TP
+\fB-cmd \fIstr\fR
+Run the timeline over a custom suspend command, e.g. pm-suspend. By default
+the tool forces suspend via /sys/power/state so this allows testing over
+an OS's official suspend method. The output file will change to
+hostname_command.html and will autodetect which suspend mode was triggered.
+.TP
+\fB-filter \fI"d1,d2,..."\fR
+Filter out all but these device callbacks. These strings can be device names
+or module names. e.g. 0000:00:02.0, ata5, i915, usb, etc.
+.TP
+\fB-mindev \fIt\fR
+Discard all device callbacks shorter than \fIt\fR milliseconds (default: 0.0).
+This reduces the html file size as there can be many tiny callbacks which are barely
+visible. The value is a float: e.g. 0.001 represents 1 us.
+.TP
+\fB-proc\fR
+Add usermode process info into the timeline (default: disabled).
+.TP
+\fB-dev\fR
+Add kernel source calls and threads to the timeline (default: disabled).
+.TP
+\fB-x2\fR
+Run two suspend/resumes back to back (default: disabled).
+.TP
+\fB-x2delay \fIt\fR
+Include \fIt\fR ms delay between multiple test runs (default: 0 ms).
+.TP
+\fB-predelay \fIt\fR
+Include \fIt\fR ms delay before 1st suspend (default: 0 ms).
+.TP
+\fB-postdelay \fIt\fR
+Include \fIt\fR ms delay after last resume (default: 0 ms).
+.TP
+\fB-multi \fIn d\fR
+Used for endurance testing. If \fIn\fR is entirely numeric, it's treated as a count:
+Execute \fIn\fR consecutive tests at \fId\fR second intervals.
+If \fIn\fR is an integer followed by a "d", "h", or "m", it's treated as a duration:
+Execute tests continuously over \fIn\fR days, hours, or minutes at \fId\fR second intervals.
+The outputs will be created in a new subdirectory, for count: suspend-{date}-{time}-xN,
+for duration: suspend-{date}-{time}-Nm. When the multitest run is done, the \fI-summary\fR
+command is called automatically to create summary html files for all the data (unless you
+use \fI-skiphtml\fR). \fI-skiphtml\fR will speed up the testing by not creating timelines
+or summary html files. You can then run the tool again at a later time with \fI-summary\fR
+and \fI-genhtml\fR to create the timelines.
+.TP
+\fB-maxfail \fIn\fR
+Abort a -multi run after \fIn\fR consecutive fails. 0 means never abort (default = 0).
+.TP
+\fB-skiphtml\fR
+Run the test and capture the trace logs, but skip the timeline generation.
+You can generate the html timelines later with \fI-dmesg\fR & \fI-ftrace\fR, or
+by running \fI-summary\fR and \fI-genhtml\fR.
+
+.SS "ftrace debug"
+.TP
+\fB-f\fR
+Use ftrace to create device callgraphs (default: disabled). This can produce
+very large outputs, i.e. 10MB - 100MB.
+.TP
+\fB-ftop\fR
+Use ftrace on the top level call: "suspend_devices_and_enter" only (default: disabled).
+This option implies -f and creates a single callgraph covering all of suspend/resume.
+.TP
+\fB-maxdepth \fIlevel\fR
+limit the callgraph trace depth to \fIlevel\fR (default: 0=all). This is
+the best way to limit the output size when using callgraphs via -f.
+.TP
+\fB-expandcg\fR
+pre-expand the callgraph data in the html output (default: disabled)
+.TP
+\fB-fadd \fIfile\fR
+Add functions to be graphed in the timeline from a list in a text file
+.TP
+\fB-mincg \fIt\fR
+Discard all callgraphs shorter than \fIt\fR milliseconds (default: 0.0).
+This reduces the html file size as there can be many tiny callgraphs
+which are barely visible in the timeline.
+The value is a float: e.g. 0.001 represents 1 us.
+.TP
+\fB-cgfilter \fI"func1,func2,..."\fR
+Reduce callgraph output in the timeline by limiting it certain devices. The
+argument can be a single device name or a comma delimited list.
+(default: none)
+.TP
+\fB-cgskip \fIfile\fR
+Reduce callgraph timeline size by skipping over uninteresting functions
+in the trace, e.g. printk or console_unlock. The functions listed
+in this file will show up as empty leaves in the callgraph with only the start/end
+times displayed. cgskip.txt is used automatically if found in the path, so
+use "off" to disable completely (default: cgskip.txt)
+.TP
+\fB-cgphase \fIp\fR
+Only show callgraph data for phase \fIp\fR (e.g. suspend_late).
+.TP
+\fB-cgtest \fIn\fR
+In an x2 run, only show callgraph data for test \fIn\fR (e.g. 0 or 1).
+.TP
+\fB-timeprec \fIn\fR
+Number of significant digits in timestamps (0:S, [3:ms], 6:us).
+.TP
+\fB-bufsize \fIN\fR
+Set trace buffer size to N kilo-bytes (default: all of free memory up to 3GB)
+
+.SH COMMANDS
+.TP
+\fB-summary \fIindir\fR
+Create a set of summary pages for all tests in \fIindir\fR recursively.
+Creates summary.html, summary-issues.html, and summary-devices.html in the current folder.
+summary.html is a table of tests with relevant info sorted by kernel/host/mode,
+and links to the test html files. It identifies the minimum, maximum, and median
+suspend and resume times for you with highlights and links in the header.
+summary-issues.html is a list of kernel issues found in dmesg from all the tests.
+summary-devices.html is a list of devices and times from all the tests.
+
+Use \fI-genhtml\fR to regenerate any tests with missing html.
+.TP
+\fB-genhtml\fR
+Used with \fI-summary\fR to regenerate any missing html timelines from their
+dmesg and ftrace logs. This will require a significant amount of time if there
+are thousands of tests.
+.TP
+\fB-modes\fR
+List available suspend modes.
+.TP
+\fB-status\fR
+Test to see if the system is able to run this tool. Use this along
+with any options you intend to use to see if they will work.
+.TP
+\fB-fpdt\fR
+Print out the contents of the ACPI Firmware Performance Data Table.
+.TP
+\fB-wificheck\fR
+Print out wifi status and connection details.
+.TP
+\fB-xon/-xoff/-xstandby/-xsuspend\fR
+Test xset by attempting to switch the display to the given mode. This
+is the same command which will be issued by \fB-display \fImode\fR.
+.TP
+\fB-xstat\fR
+Get the current DPMS display mode.
+.TP
+\fB-sysinfo\fR
+Print out system info extracted from BIOS. Reads /dev/mem directly instead of going through dmidecode.
+.TP
+\fB-devinfo\fR
+Print out the pm settings of all devices which support runtime suspend.
+.TP
+\fB-cmdinfo\fR
+Print out all the platform data collected from the system that makes it into the logs.
+.TP
+\fB-flist\fR
+Print the list of ftrace functions currently being captured. Functions
+that are not available as symbols in the current kernel are shown in red.
+By default, the tool traces a list of important suspend/resume functions
+in order to better fill out the timeline. If the user has added their own
+with -fadd they will also be checked.
+.TP
+\fB-flistall\fR
+Print all ftrace functions capable of being captured. These are all the
+possible values you can add to trace via the -fadd argument.
+.SS "rebuild"
+.TP
+\fB-ftrace \fIfile\fR
+Create HTML output from an existing ftrace file.
+.TP
+\fB-dmesg \fIfile\fR
+Create HTML output from an existing dmesg file.
+
+.SH EXAMPLES
+.SS "simple commands"
+Check which suspend modes are currently supported.
+.IP
+\f(CW$ sleepgraph -modes\fR
+.PP
+Read the Firmware Performance Data Table (FPDT)
+.IP
+\f(CW$ sudo sleepgraph -fpdt\fR
+.PP
+Print out the current USB power topology
+.IP
+\f(CW$ sleepgraph -usbtopo
+.PP
+Verify that you can run a command with a set of arguments
+.IP
+\f(CW$ sudo sleepgraph -f -rtcwake 30 -status
+.PP
+Generate a summary of all timelines in a particular folder.
+.IP
+\f(CW$ sleepgraph -summary ~/workspace/myresults/\fR
+.PP
+
+.SS "capturing basic timelines"
+Execute a mem suspend with a 15 second wakeup. Include the logs in the html.
+.IP
+\f(CW$ sudo sleepgraph -rtcwake 15 -addlogs\fR
+.PP
+Execute a standby with a 15 second wakeup. Change the output folder name.
+.IP
+\f(CW$ sudo sleepgraph -m standby -rtcwake 15 -o "standby-{host}-{date}-{time}"\fR
+.PP
+Execute a freeze with no wakeup (require keypress). Change output folder name.
+.IP
+\f(CW$ sudo sleepgraph -m freeze -rtcwake off -o "freeze-{hostname}-{date}-{time}"\fR
+.PP
+
+.SS "capturing advanced timelines"
+Execute a suspend & include dev mode source calls, limit callbacks to 5ms or larger.
+.IP
+\f(CW$ sudo sleepgraph -m mem -rtcwake 15 -dev -mindev 5\fR
+.PP
+Run two suspends back to back, include a 500ms delay before, after, and in between runs.
+.IP
+\f(CW$ sudo sleepgraph -m mem -rtcwake 15 -x2 -predelay 500 -x2delay 500 -postdelay 500\fR
+.PP
+Execute a suspend using a custom command.
+.IP
+\f(CW$ sudo sleepgraph -cmd "echo mem > /sys/power/state" -rtcwake 15\fR
+.PP
+
+.SS "endurance testing using -multi"
+.PP
+Do a batch run of 10 freezes with 30 seconds delay between runs.
+.IP
+\f(CW$ sudo sleepgraph -m freeze -rtcwake 15 -multi 10 30\fR
+.PP
+Do a batch run of freezes for 24 hours.
+.IP
+\f(CW$ sudo sleepgraph -m freeze -rtcwake 15 -multi 24h 0\fR
+
+.SS "adding callgraph data"
+Add device callgraphs. Limit the trace depth and only show callgraphs 10ms or larger.
+.IP
+\f(CW$ sudo sleepgraph -m mem -rtcwake 15 -f -maxdepth 5 -mincg 10\fR
+.PP
+Capture a full callgraph across all suspend, then filter the html by a single phase.
+.IP
+\f(CW$ sudo sleepgraph -m mem -rtcwake 15 -f\fR
+.IP
+\f(CW$ sleepgraph -dmesg host_mem_dmesg.txt -ftrace host_mem_ftrace.txt -f -cgphase resume
+.PP
+
+.SS "rebuild timeline from logs"
+.PP
+Rebuild the html from a previous run's logs, using the same options.
+.IP
+\f(CW$ sleepgraph -dmesg dmesg.txt -ftrace ftrace.txt -callgraph\fR
+.PP
+Rebuild the html with different options.
+.IP
+\f(CW$ sleepgraph -dmesg dmesg.txt -ftrace ftrace.txt -addlogs -srgap\fR
+
+.SH "SEE ALSO"
+dmesg(1)
+.PP
+.SH AUTHOR
+.nf
+Written by Todd Brandt <todd.e.brandt@linux.intel.com>