This is a tool that is intended to work around the fact that the preemptoff, irqsoff, and preemptirqsoff tracers only work in overwrite mode. The idea is to act randomly in such a way that we do not systematically lose any latencies, so that if enough testing is done, all latencies will be captured. If the same burst of latencies is repeated, then sooner or later we will have captured all the latencies. It also works with the wakeup_dl, wakeup_rt, and wakeup tracers. However, in that case it is probably not useful to use the random sleep functionality. The reason why it may be desirable to catch all latencies with a long test campaign is that for some organizations, it's necessary to test the kernel in the field and not practical for developers to work iteratively with field testers. Because of cost and project schedules it is not possible to start a new test campaign every time a latency problem has been fixed. It uses inotify to detect changes to /sys/kernel/tracing/trace. When a latency is detected, it will either sleep or print immediately, depending on a function that act as an unfair coin toss. If immediate print is chosen, it means that we open /sys/kernel/tracing/trace and thereby cause a blackout period that will hide any subsequent latencies. If sleep is chosen, it means that we wait before opening /sys/kernel/tracing/trace, by default for 1000 ms, to see if there is another latency during this period. If there is, then we will lose the previous latency. The coin will be tossed again with a different probability, and we will either print the new latency, or possibly a subsequent one. The probability for the unfair coin toss is chosen so that there is equal probability to obtain any of the latencies in a burst. However, this assumes that we make an assumption of how many latencies there can be. By default the program assumes that there are no more than 2 latencies in a burst, the probability of immediate printout will be: 1/2 and 1 Thus, the probability of getting each of the two latencies will be 1/2. If we ever find that there is more than one latency in a series, meaning that we reach the probability of 1, then the table will be expanded to: 1/3, 1/2, and 1 Thus, we assume that there are no more than three latencies and each with a probability of 1/3 of being captured. If the probability of 1 is reached in the new table, that is we see more than two closely occurring latencies, then the table will again be extended, and so on. On my systems, it seems like this scheme works fairly well, as long as the latencies we trace are long enough, 300 us seems to be enough. This userspace program receive the inotify event at the end of a latency, and it has time until the end of the next latency to react, that is to open /sys/kernel/tracing/trace. Thus, if we trace latencies that are >300 us, then we have at least 300 us to react. The minimum latency will of course not be 300 us on all systems, it will depend on the hardware, kernel version, workload and configuration. Example usage: In one shell, give the following command: sudo latency-collector -rvv -t preemptirqsoff -s 2000 -a 3 This will trace latencies > 2000us with the preemptirqsoff tracer, using random sleep with maximum verbosity, with a probability table initialized to a size of 3. In another shell, generate a few bursts of latencies: root@host:~# modprobe preemptirq_delay_test delay=3000 test_mode=alternate burst_size=3 root@host:~# echo 1 > /sys/kernel/preemptirq_delay_test/trigger root@host:~# echo 1 > /sys/kernel/preemptirq_delay_test/trigger root@host:~# echo 1 > /sys/kernel/preemptirq_delay_test/trigger root@host:~# echo 1 > /sys/kernel/preemptirq_delay_test/trigger If all goes well, you should be getting stack traces that shows all the different latencies, i.e. you should see all the three functions preemptirqtest_0, preemptirqtest_1, preemptirqtest_2 in the stack traces. Link: https://lkml.kernel.org/r/20210212134421.172750-2-Viktor.Rosendahl@bmw.de Signed-off-by: Viktor Rosendahl <Viktor.Rosendahl@bmw.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The resolve_btfids tool will be used during the vmlinux linking, so it's necessary it's ready for it. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200711215329.41165-3-jolsa@kernel.org
Add "bootconfig" command which operates the bootconfig config-data on initrd image. User can add/delete/verify the boot config on initrd image using this command. e.g. Add a boot config to initrd image # bootconfig -a myboot.conf /boot/initrd.img Remove it. # bootconfig -d /boot/initrd.img Or verify (and show) it. # bootconfig /boot/initrd.img Link: http://lkml.kernel.org/r/157867223582.17873.14342161849213219982.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [ Removed extra blank line at end of bootconfig.c ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When `make help` is executed it lists the possible tools to build, though couple of entries is kept unordered. Fix it here. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Song Liu <songliubraving@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Yonghong Song <yhs@fb.com> Link: https://lkml.kernel.org/n/tip-0ke3p64ksa0hnbueh52n3v3q@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The Intel(R) Speed select technologies contains four features. Performance profile:An non architectural mechanism that allows multiple optimized performance profiles per system via static and/or dynamic adjustment of core count, workload, Tjmax, and TDP, etc. aka ISS in the documentation. Base Frequency: Enables users to increase guaranteed base frequency on certain cores (high priority cores) in exchange for lower base frequency on remaining cores (low priority cores). aka PBF in the documenation. Turbo frequency: Enables the ability to set different turbo ratio limits to cores based on priority. aka FACT in the documentation. Core power: An Interface that allows user to define per core/tile priority. There is a multi level help for commands and options. This can be used to check required arguments for each feature and commands for the feature. To start navigating the features start with $sudo intel-speed-select --help For help on a specific feature for example $sudo intel-speed-select perf-profile --help To get help for a command for a feature for example $sudo intel-speed-select perf-profile get-lock-status --help Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Acked-by: Len Brown <len.brown@intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Add a script to the tools/ directory that shows if or why the running kernel was tainted. The script was mostly written by Randy Dunlap; I enhanced the script a bit. There does not appear to be a good home for this script. so create tools/debugging for tools of this nature. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info> [ jc: fixed conflicts, rewrote changelog ] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Commit 5620a0d1aacd ("firmware: delete in-kernel firmware") removed
ihex2fw tool together with the rest of the contents of firmware/
folder. Since that tool is quite useful for doing .ihex -> .fw
converstion, restore its original source code to tools/firmware
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change tool compiling process in order to be build using the same mechanism used in other linux tools (e.g. iio, perf, etc). This will allow in future the buildroot tool to build and integrate this tool in a more expeditious way. Update documentation accordingly. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com>
Pull x86 platform driver updates from Andy Shevchenko: "Here is the collected material against Platform Drivers x86 subsystem. It's rather bit busy cycle for PDx86, mostly due to Dell SMBIOS driver activity For this cycle we have quite an update for the Dell SMBIOS driver including WMI work to provide an interface for SMBIOS tokens via sysfs and WMI support for 2017+ Dell laptop models. SMM dispatcher code is split into a separate driver followed by a new WMI dispatcher. The latter provides a character device interface to user space. The git history also contains a merge of immutable branch from Wolfram Sang in order to apply a dependent fix to the Intel CherryTrail Battery Management driver. Other Intel drivers got a lot of cleanups. The Turbo Boost Max 3.0 support is added for Intel Skylake. Peaq WMI hotkeys driver gets its own maintainer and white list of supported models. Silead DMI is expanded to support few additional platforms. Tablet mode via GMMS ACPI method is added to support some ThinkPad tablets. new driver: - Add driver to force WMI Thunderbolt controller power status asus-wmi: - Add lightbar led support dell-laptop: - Allocate buffer before rfkill use dell-smbios: - fix string overflow - Add filtering support - Introduce dispatcher for SMM calls - Add a sysfs interface for SMBIOS tokens - only run if proper oem string is detected - Prefix class/select with cmd_ - Add pr_fmt definition to driver dell-smbios-smm: - test for WSMT dell-smbios-wmi: - release mutex lock on WMI call failure - introduce userspace interface - Add new WMI dispatcher driver dell-smo8800: - remove redundant assignments to byte_data dell-wmi: - don't check length returned - clean up wmi descriptor check - increase severity of some failures - Do not match on descriptor GUID modalias - Label driver as handling notifications dell-*wmi*: - Relay failed initial probe to dependent drivers dell-wmi-descriptor: - check if memory was allocated - split WMI descriptor into it's own driver fujitsu-laptop: - Fix radio LED detection - Don't oops when FUJ02E3 is not presnt hp_accel: - Add quirk for HP ProBook 440 G4 hp-wmi: - Fix tablet mode detection for convertibles ideapad-laptop: - Add Lenovo Yoga 920-13IKB to no_hw_rfkill dmi list intel_cht_int33fe: - Update fusb302 type string, add properties - make a couple of local functions static - Work around BIOS bug on some devices intel-hid: - Power button suspend on Dell Latitude 7275 intel_ips: - Convert timers to use timer_setup() - Remove FSF address from GPL notice - Remove unneeded fields and label - Keep pointer to struct device - Use PCI_VDEVICE() macro - Switch to new PCI IRQ allocation API - Simplify error handling via devres API intel_pmc_ipc: - Revert Use MFD framework to create dependent devices - Use MFD framework to create dependent devices - Use spin_lock to protect GCR updates - Use devm_* calls in driver probe function intel_punit_ipc: - Fix resource ioremap warning intel_telemetry: - Remove useless default in Kconfig - Add needed inclusion - cleanup redundant headers - Fix typos - Fix load failure info intel_telemetry_debugfs: - Use standard ARRAY_SIZE() macro intel_turbo_max_3: - Add Skylake platform intel-wmi-thunderbolt: - Silence error cases mlx-platform: - make a couple of structures static peaq_wmi: - Fix missing terminating entry for peaq_dmi_table peaq-wmi: - Remove unnecessary checks from peaq_wmi_exit - Add DMI check before binding to the WMI interface - Revert Blacklist Lenovo ideapad 700-15ISK - Blacklist Lenovo ideapad 700-15ISK silead_dmi: - Add silead, home-button property to some tablets - Add entry for the Digma e200 tablet - Fix GP-electronic T701 entry - Add entry for the Chuwi Hi8 Pro tablet sony-laptop: - Drop variable assignment in sony_nc_setup_rfkill() - Fix error handling in sony_nc_setup_rfkill() thinkpad_acpi: - Implement tablet mode using GMMS method tools/wmi: - add a sample for dell smbios communication over WMI wmi: - release mutex on module acquistion failure - create userspace interface for drivers - Don't allow drivers to get each other's GUIDs - Add new method wmidev_evaluate_method - Destroy on cleanup rather than unregister - Cleanup exit routine in reverse order of init - Sort include list" * tag 'platform-drivers-x86-v4.15-1' of git://git.infradead.org/linux-platform-drivers-x86: (74 commits) platform/x86: silead_dmi: Add silead, home-button property to some tablets platform/x86: dell-laptop: Allocate buffer before rfkill use platform/x86: dell-*wmi*: Relay failed initial probe to dependent drivers platform/x86: dell-wmi-descriptor: check if memory was allocated platform/x86: Revert intel_pmc_ipc: Use MFD framework to create dependent devices platform/x86: dell-smbios-wmi: release mutex lock on WMI call failure platform/x86: wmi: release mutex on module acquistion failure platform/x86: dell-smbios: fix string overflow platform/x86: intel_pmc_ipc: Use MFD framework to create dependent devices platform/x86: intel_punit_ipc: Fix resource ioremap warning platform/x86: dell-smo8800: remove redundant assignments to byte_data platform/x86: hp-wmi: Fix tablet mode detection for convertibles platform/x86: intel_ips: Convert timers to use timer_setup() platform/x86: sony-laptop: Drop variable assignment in sony_nc_setup_rfkill() platform/x86: sony-laptop: Fix error handling in sony_nc_setup_rfkill() tools/wmi: add a sample for dell smbios communication over WMI platform/x86: dell-smbios-wmi: introduce userspace interface platform/x86: wmi: create userspace interface for drivers platform/x86: dell-smbios: Add filtering support platform/x86: dell-smbios-smm: test for WSMT ...