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2023-06-13rtla/timerlat_hist: Add timerlat user-space supportDaniel Bristot de Oliveira
Add the support for running timerlat threads in user-space. In this mode, enabled with -u/--user-threads, timerlat dispatches user-space processes that will loop in the timerlat_fd, measuring the overhead for going to user-space and then returning to the kernel - in addition to the existing measurements. Here is one example of the tool's output with -u enabled: $ sudo timerlat hist -u -c 1-3 -d 600 # RTLA timerlat histogram # Time unit is microseconds (us) # Duration: 0 00:10:01 Index IRQ-001 Thr-001 Usr-001 IRQ-002 Thr-002 Usr-002 IRQ-003 Thr-003 Usr-003 0 477555 0 0 425287 0 0 474357 0 0 1 122385 7998 0 174616 1921 0 125412 3138 0 2 47 587376 492150 89 594717 447830 147 593463 454872 3 11 2549 101930 7 2682 145580 64 2530 138680 4 3 1954 2833 1 463 4917 11 548 4656 5 0 60 1037 0 138 1117 6 179 1130 6 0 26 1837 0 38 277 1 76 339 7 0 15 143 0 28 147 2 37 156 8 0 10 23 0 11 75 0 12 80 9 0 7 17 0 0 26 0 11 42 10 0 2 11 0 0 18 0 2 20 11 0 0 7 0 1 8 0 2 12 12 0 0 6 0 1 4 0 2 8 13 0 1 3 0 0 0 0 0 1 14 0 1 0 0 0 1 0 0 2 15 0 1 0 0 0 0 0 0 2 16 0 1 2 0 0 0 0 0 0 17 0 0 1 0 0 0 0 0 0 19 0 0 1 0 0 0 0 0 0 over: 0 0 0 0 0 0 0 0 0 count: 600001 600001 600001 600000 600000 600000 600000 600000 600000 min: 0 1 2 0 1 2 0 1 2 avg: 0 1 2 0 2 2 0 2 2 max: 4 16 19 4 12 14 7 12 15 The tuning setup like -p or -C work for the user-space threads as well. Link: https://lkml.kernel.org/r/b6a042d55003c4a67ff7dce28d96044b7044f00d.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla/timerlat_top: Add timerlat user-space supportDaniel Bristot de Oliveira
Add the support for running timerlat threads in user-space. In this mode, enabled with -u/--user-threads, timerlat dispatches user-space processes that will loop in the timerlat_fd, measuring the overhead for going to user-space and then returning to the kernel - in addition to the existing measurements. Here is one example of the tool's output with -u enabled: $ sudo timerlat top -u -d 600 -q Timer Latency 0 00:10:01 | IRQ Timer Latency (us) | Thread Timer Latency (us) | Ret user Timer Latency (us) CPU COUNT | cur min avg max | cur min avg max | cur min avg max 0 #600001 | 0 0 0 3 | 2 1 2 9 | 3 2 3 15 1 #600001 | 0 0 0 2 | 2 1 2 13 | 2 2 3 18 2 #600001 | 0 0 0 10 | 2 1 2 16 | 3 2 3 20 3 #600001 | 0 0 0 7 | 2 1 2 10 | 3 2 3 11 4 #600000 | 0 0 0 16 | 2 1 2 41 | 3 2 3 58 5 #600000 | 0 0 0 3 | 2 1 2 10 | 3 2 3 13 6 #600000 | 0 0 0 5 | 2 1 2 7 | 3 2 3 10 7 #600000 | 0 0 0 1 | 2 1 2 7 | 3 2 3 10 The tuning setup like -p or -C work for the user-space threads as well. Link: https://lkml.kernel.org/r/758ad2292a0a1d884138d08219e1a0f572d257a2.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla/hwnoise: Reduce runtime to 75%Daniel Bristot de Oliveira
osnoise runs 100% of time by default. It makes sense because osnoise is preemptive. hwnoise checks preemption once a second, so it reduces system progress. Reduce runtime to 75% to avoid problems by default. I added a Fixes as it might avoid problems for first time users as it lands on distros. Link: https://lkml.kernel.org/r/af0b7113ffc00031b9af4bb40ef5889a27dadf8c.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Fixes: 1f428356c38d ("rtla: Add hwnoise tool") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla: Start the tracers after creating all instancesDaniel Bristot de Oliveira
Group all start tracing after finishing creating all instances. The tracing instance starts first for the case of hitting a stop tracing while enabling other instances. The trace instance is the one with most valuable information. Link: https://lkml.kernel.org/r/67da7a703a56f75d7cd46568525145a65501a7e8.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla/timerlat_hist: Add auto-analysis supportDaniel Bristot de Oliveira
Add auto-analysis to timerlat hist, including the --no-aa option to reduce overhead and --dump-task. --aa-only was not added as it is already on timerlat top. Link: https://lkml.kernel.org/r/c2693f47ee83e659a7723fed8035f5d2534f528e.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla/timerlat: Give timerlat auto analysis its own instanceDaniel Bristot de Oliveira
Currently, the auto-analysis is attached to the timerlat top instance. The idea was to avoid creating another instance just for that, so one instance could be reused. The drawback is that, by doing so, the auto-analysis run for the entire session, consuming CPU time. On my 24 box CPUs for timerlat with a 100 us period consumed 50 % with auto analysis, but only 16 % without. By creating an instance for auto-analysis, we can keep the processing stopped until a stop tracing condition is hit. Once it happens, timerlat auto-analysis can use its own trace instance to parse only the end of the trace. By doing so, auto-analysis stop consuming cpu time when it is not needed. If the --aa-only is passed, the timerlat top instance is reused for auto analysis. Link: https://lkml.kernel.org/r/346b7168c1bae552a415715ec6d23c129a43bdb7.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla: Automatically move rtla to a house-keeping cpuDaniel Bristot de Oliveira
When the user sets -c <cpu-list> try to move rtla out of the <cpu-list>, even without an -H option. This is useful to avoid having rtla interfering with the workload. This works by removing <cpu-list> from rtla's current affinity. If rtla fails to move itself away it is not that of a problem as this is an automatic measure. Link: https://lkml.kernel.org/r/c54304d90c777310fb85a3e658d1449173759aab.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla: Change monitored_cpus from char * to cpu_set_tDaniel Bristot de Oliveira
Use a cpumask instead of a char *, reducing memory footprint and code. No functional change, and in preparation for auto house-keeping. Link: https://lkml.kernel.org/r/54c46293261d13cb1042d0314486539eeb45fe5d.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla: Add --house-keeping optionDaniel Bristot de Oliveira
To avoid having rtla interfering with the measurement threads, add an option for the user to set the CPUs in which rtla should run. For instance: # rtla timerlat top -H 0 -c 1-7 Will place rtla in the CPU 0, while running the measurement threads in the CPU 1-7. Link: https://lkml.kernel.org/r/6a6c78a579a96ba8b02ae67ee1e0ba2cb5e03c4a.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Suggested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-13rtla: Add -C cgroup supportDaniel Bristot de Oliveira
The -C option sets a cgroup to the tracer's threads. If the -C option is passed without arguments, the tracer's thread will inherit rtla's cgroup. Otherwise, the threads will be placed on the cgroup passed to the option. Link: https://lkml.kernel.org/r/cb051477331d292f17c08bf1d66f0e0384bbe5a5.1686066600.git.bristot@kernel.org Cc: William White <chwhite@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25rtla/timerlat: Fix "Previous IRQ" auto analysis' lineDaniel Bristot de Oliveira
The "Previous IRQ interference" line is misaligned and without a \n, breaking the tool's output: ## CPU 12 hit stop tracing, analyzing it ## Previous IRQ interference: up to 2.22 us IRQ handler delay: 18.06 us (0.00 %) IRQ latency: 18.52 us Timerlat IRQ duration: 4.41 us (0.00 %) Blocking thread: 216.93 us (0.03 %) Fix the output: ## CPU 7 hit stop tracing, analyzing it ## Previous IRQ interference: up to 8.93 us IRQ handler delay: 0.98 us (0.00 %) IRQ latency: 2.95 us Timerlat IRQ duration: 11.26 us (0.03 %) Link: https://lore.kernel.org/linux-trace-devel/8b5819077f15ccf24745c9bf3205451e16ee32d9.1679685525.git.bristot@kernel.org Fixes: 27e348b221f6 ("rtla/timerlat: Add auto-analysis core") Cc: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-25rtla/timerlat: Add auto-analysis only optionDaniel Bristot de Oliveira
Parsing and formating timerlat data might consume a reasonable amount of CPU time on very large systems, or when timerlat has a too short period. Add an option to run timerlat with auto-analysis enabled while skipping the statistics parsing. In this mode, rtla timerlat periodically checks if the tracing is on, going to sleep waiting for the stop tracing condition to stop tracing, or for the tracing session to finish. If the stop tracing condition is hit, the tool prints the auto analysis. Otherwise, the tool prints the max observed latency and exit. The max observed latency is captured via tracing_max_latency. Link: https://lore.kernel.org/linux-trace-devel/4dc514d1d5dc353c537a466a9b5af44c266b6da2.1680106912.git.bristot@kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-13rtla: Add hwnoise toolDaniel Bristot de Oliveira
The hwnoise tool is a special mode for the osnoise top tool. hwnoise dispatches the osnoise tracer and displays a summary of the noise. The difference is that it runs the tracer with the OSNOISE_IRQ_DISABLE option set, thus only allowing only hardware-related noise, resulting in a simplified output. hwnoise has the same features of osnoise. An example of the tool's output: # rtla hwnoise -c 1-11 -T 1 -d 10m -q Hardware-related Noise duration: 0 00:10:00 | time is in us CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI 1 #599 599000000 138 99.99997 3 3 4 74 2 #599 599000000 85 99.99998 3 3 4 75 3 #599 599000000 86 99.99998 4 3 6 75 4 #599 599000000 81 99.99998 4 4 2 75 5 #599 599000000 85 99.99998 2 2 2 75 Link: https://lkml.kernel.org/r/2d6f49a6f3a4f8b51b2c806458b1cff71ad4d014.1675805361.git.bristot@kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-02rtla/timerlat: Add auto-analysis support to timerlat topDaniel Bristot de Oliveira
Currently, timerlat top displays the timerlat tracer latency results, saving the intuitive timerlat trace for the developer to analyze. This patch goes a step forward in the automaton of the scheduling latency analysis by providing a summary of the root cause of a latency higher than the passed "stop tracing" parameter if the trace stops. The output is intuitive enough for non-expert users to have a general idea of the root cause by looking at each factor's contribution percentage while keeping the technical detail in the output for more expert users to start an in dept debug or to correlate a root cause with an existing one. The terminology is in line with recent industry and academic publications to facilitate the understanding of both audiences. Here is one example of tool output: ----------------------------------------- %< ----------------------------------------------------- # taskset -c 0 timerlat -a 40 -c 1-23 -q Timer Latency 0 00:00:12 | IRQ Timer Latency (us) | Thread Timer Latency (us) CPU COUNT | cur min avg max | cur min avg max 1 #12322 | 0 0 1 15 | 10 3 9 31 2 #12322 | 3 0 1 12 | 10 3 9 23 3 #12322 | 1 0 1 21 | 8 2 8 34 4 #12322 | 1 0 1 17 | 10 2 11 33 5 #12322 | 0 0 1 12 | 8 3 8 25 6 #12322 | 1 0 1 14 | 16 3 11 35 7 #12322 | 0 0 1 14 | 9 2 8 29 8 #12322 | 1 0 1 22 | 9 3 9 34 9 #12322 | 0 0 1 14 | 8 2 8 24 10 #12322 | 1 0 0 12 | 9 3 8 24 11 #12322 | 0 0 0 15 | 6 2 7 29 12 #12321 | 1 0 0 13 | 5 3 8 23 13 #12319 | 0 0 1 14 | 9 3 9 26 14 #12321 | 1 0 0 13 | 6 2 8 24 15 #12321 | 1 0 1 15 | 12 3 11 27 16 #12318 | 0 0 1 13 | 7 3 10 24 17 #12319 | 0 0 1 13 | 11 3 9 25 18 #12318 | 0 0 0 12 | 8 2 8 20 19 #12319 | 0 0 1 18 | 10 2 9 28 20 #12317 | 0 0 0 20 | 9 3 8 34 21 #12318 | 0 0 0 13 | 8 3 8 28 22 #12319 | 0 0 1 11 | 8 3 10 22 23 #12320 | 28 0 1 28 | 41 3 11 41 rtla timerlat hit stop tracing ## CPU 23 hit stop tracing, analyzing it ## IRQ handler delay: 27.49 us (65.52 %) IRQ latency: 28.13 us Timerlat IRQ duration: 9.59 us (22.85 %) Blocking thread: 3.79 us (9.03 %) objtool:49256 3.79 us Blocking thread stacktrace -> timerlat_irq -> __hrtimer_run_queues -> hrtimer_interrupt -> __sysvec_apic_timer_interrupt -> sysvec_apic_timer_interrupt -> asm_sysvec_apic_timer_interrupt -> _raw_spin_unlock_irqrestore -> cgroup_rstat_flush_locked -> cgroup_rstat_flush_irqsafe -> mem_cgroup_flush_stats -> mem_cgroup_wb_stats -> balance_dirty_pages -> balance_dirty_pages_ratelimited_flags -> btrfs_buffered_write -> btrfs_do_write_iter -> vfs_write -> __x64_sys_pwrite64 -> do_syscall_64 -> entry_SYSCALL_64_after_hwframe ------------------------------------------------------------------------ Thread latency: 41.96 us (100%) The system has exit from idle latency! Max timerlat IRQ latency from idle: 17.48 us in cpu 4 Saving trace to timerlat_trace.txt ----------------------------------------- >% ----------------------------------------------------- In this case, the major factor was the delay suffered by the IRQ handler that handles timerlat wakeup: 65.52 %. This can be caused by the current thread masking interrupts, which can be seen in the blocking thread stacktrace: the current thread (objtool:49256) disabled interrupts via raw spin lock operations inside mem cgroup, while doing write syscall in a btrfs file system. A simple search for the function name on Google shows that this is a legit case for disabling the interrupts: cgroup: Use irqsave in cgroup_rstat_flush_locked() lore.kernel.org/linux-mm/20220301122143.1521823-2-bigeasy@linutronix.de/ The output also prints other reasons for the latency root cause, such as: - an IRQ that happened before the IRQ handler that caused delays - The interference from NMI, IRQ, Softirq, and Threads The details about how these factors affect the scheduling latency can be found here: https://bristot.me/demystifying-the-real-time-linux-latency/ Link: https://lkml.kernel.org/r/3d45f40e630317f51ac6d678e2d96d310e495729.1675179318.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-02rtla/timerlat: Add auto-analysis coreDaniel Bristot de Oliveira
Currently, timerlat displays a summary of the timerlat tracer results saving the trace if the system hits a stop condition. While this represented a huge step forward, the root cause was not that is accessible to non-expert users. The auto-analysis fulfill this gap by parsing the trace timerlat runs, printing an intuitive auto-analysis. Link: https://lkml.kernel.org/r/1ee073822f6a2cbb33da0c817331d0d4045e837f.1675179318.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-31tools/tracing/rtla: osnoise_hist: display average with two-digit precisionAndreas Ziegler
Calculate average value in osnoise-hist summary with two-digit precision to avoid displaying too optimitic results. Link: https://lkml.kernel.org/r/20230103103400.275566-3-br015@umbiko.net Signed-off-by: Andreas Ziegler <br015@umbiko.net> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-31tools/tracing/rtla: osnoise_hist: use total duration for average calculationAndreas Ziegler
Sampled durations must be weighted by observed quantity, to arrive at a correct average duration value. Perform calculation of total duration by summing (duration * count). Link: https://lkml.kernel.org/r/20230103103400.275566-2-br015@umbiko.net Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode") Signed-off-by: Andreas Ziegler <br015@umbiko.net> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-12-09rtla: Fix exit status when returning from calls to usage()John Kacur
rtla_usage(), osnoise_usage() and timerlat_usage() all exit with an error status. However when these are called from help, they should exit with a non-error status. Fix this by passing the exit status to the functions. Note, although we remove the subsequent call to exit after calling usage, we leave it in at the end of a function to suppress the compiler warning "control reaches end of a non-void function". Link: https://lkml.kernel.org/r/20221107144313.22470-1-jkacur@redhat.com Signed-off-by: John Kacur <jkacur@redhat.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-10rtla: Fix tracer nameAlexandre Vicenzi
The correct tracer name is timerlat and not timelat. Link: https://lore.kernel.org/linux-trace-devel/20220808180343.22262-1-alexandre.vicenzi@suse.com Signed-off-by: Alexandre Vicenzi <alexandre.vicenzi@suse.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-31rtla: Define syscall numbers for riscvAndreas Schwab
RISC-V uses the same (generic) syscall numbers as ARM64. Link: https://lkml.kernel.org/r/mvma68wl2ul.fsf@suse.de Signed-off-by: Andreas Schwab <schwab@suse.de> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-31rtla: Fix double freeAndreas Schwab
Avoid double free by making trace_instance_destroy indempotent. When trace_instance_init fails, it calls trace_instance_destroy, but its only caller osnoise_destroy_tool calls it again. Link: https://lkml.kernel.org/r/mvmilnlkyzx.fsf_-_@suse.de Fixes: 0605bf009f18 ("rtla: Add osnoise tool") Signed-off-by: Andreas Schwab <schwab@suse.de> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-11rtla/utils: Use calloc and check the potential memory allocation failurejianchunfu
Replace malloc with calloc and add memory allocating check of mon_cpus before used. Link: https://lkml.kernel.org/r/20220615073348.6891-1-jianchunfu@cmss.chinamobile.com Fixes: 7d0dc9576dc3 ("rtla/timerlat: Add --dma-latency option") Signed-off-by: jianchunfu <jianchunfu@cmss.chinamobile.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26rtla: Remove procps-ng dependencyDaniel Bristot de Oliveira
Daniel Wagner reported to me that readproc.h got deprecated. Also, while the procps-ng library was available on Fedora, it was not available on RHEL, which is a piece of evidence that it was not that used. rtla uses procps-ng only to find the PID of the tracers' workload. I used the procps-ng library to avoid reinventing the wheel. But in this case, reinventing the wheel took me less time than the time we already took trying to work around problems. Implement a function that reads /proc/ entries, checking if: - the entry is a directory - the directory name is composed only of digits (PID) - the directory contains the comm file - the comm file contains a comm that matches the tracers' workload prefix. - then return true; otherwise, return false. And use it instead of procps-ng. Link: https://lkml.kernel.org/r/e8276e122ee9eb2c5a0ba8e673fb6488b924b825.1652423574.git.bristot@kernel.org Cc: John Kacur <jkacur@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tao Zhou <tao.zhou@linux.dev> Fixes: b1696371d865 ("rtla: Helper functions for rtla") Reported-by: Daniel Wagner <dwagner@suse.de> Reviewed-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26rtla: Fix __set_sched_attr error messageDaniel Bristot de Oliveira
rtla's function __set_sched_attr() was borrowed from stalld, but I forgot to update the error message to something meaningful for rtla. Update the error message from: boost_with_deadline failed to boost pid PID: STRERROR to a proper one: Failed to set sched attributes to the pid PID: STRERROR Link: https://lkml.kernel.org/r/a2d19b2c53f6512aefd1ee7f8c1bd19d4fc8b99d.1651247710.git.bristot@kernel.org Link: https://lore.kernel.org/r/eeded730413e7feaa13f946924bcf2cbf7dd9561.1650617571.git.bristot@kernel.org/ Fixes: b1696371d865 ("rtla: Helper functions for rtla") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26rtla: Avoid record NULL pointer dereferenceWan Jiabing
Fix the following null/deref_null.cocci errors: ./tools/tracing/rtla/src/osnoise_hist.c:870:31-36: ERROR: record is NULL but dereferenced. ./tools/tracing/rtla/src/osnoise_top.c:650:31-36: ERROR: record is NULL but dereferenced. ./tools/tracing/rtla/src/timerlat_hist.c:905:31-36: ERROR: record is NULL but dereferenced. ./tools/tracing/rtla/src/timerlat_top.c:700:31-36: ERROR: record is NULL but dereferenced. "record" is NULL before calling osnoise_init_trace_tool. Add a tag "out_free" to avoid dereferring a NULL pointer. Link: https://lkml.kernel.org/r/ae0e4500d383db0884eb2820286afe34ca303778.1651247710.git.bristot@kernel.org Link: https://lore.kernel.org/r/20220408151406.34823-1-wanjiabing@vivo.com/ Cc: kael_w@yeah.net Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Fixes: 51d64c3a1819 ("rtla: Add -e/--event support") Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla: Tools main loop cleanupDaniel Bristot de Oliveira
I probably started using "do {} while();", but changed all but osnoise_top to "while(){};" leaving the ; behind. Cleanup the main loop code, making all tools use "while() {}" Changcheng Deng reported this problem, as reported by coccicheck: Fix the following coccicheck review: ./tools/tracing/rtla/src/timerlat_hist.c: 800: 2-3: Unneeded semicolon ./tools/tracing/rtla/src/osnoise_hist.c: 776: 2-3: Unneeded semicolon ./tools/tracing/rtla/src/timerlat_top.c: 596: 2-3: Unneeded semicolon Link: https://lkml.kernel.org/r/3c1642110aa87c396f5da4a037dabc72dbb9c601.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Reported-by: Changcheng Deng <deng.changcheng@zte.com.cn> Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/timerlat: Add --dma-latency optionDaniel Bristot de Oliveira
Add the --dma-latency to set /dev/cpu_dma_latency to the specified value, this aims to avoid having exit from idle states latencies that could be influencing the analysis. Link: https://lkml.kernel.org/r/72ddb0d913459f13217086dadafad88a7c46dd28.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/osnoise: Fix osnoise hist stop tracing messageDaniel Bristot de Oliveira
rtla osnoise hist is printing the following message when hitting stop tracing: printf("rtla timelat hit stop tracing\n"); which is obviosly wrong. s/timerlat/osnoise/ fixing the printf. Link: https://lkml.kernel.org/r/2b8f090556fe37b81d183b74ce271421f131c77b.1646247211.git.bristot@kernel.org Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode") Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla: Check for trace off also in the trace instanceDaniel Bristot de Oliveira
With the addition of --trigger option, it is also possible to stop the trace from the -t tracing instance using the traceoff trigger. Make rtla tools to check if the trace is stopped also in the trace instance, stopping the execution of the tool. Link: https://lkml.kernel.org/r/59fc7c6f23dddd5c8b7ef1782cf3da51ea2ce0f5.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/trace: Save event histogram output to a fileDaniel Bristot de Oliveira
The hist: trigger generates a histogram in the file sys/event/hist. If the hist: trigger is used, automatically save the histogram output of the event sys:event in the sys_event_hist.txt file. Link: https://lkml.kernel.org/r/b5c906af31d4e022ffe87fb0848fac5c089087c8.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla: Add --filter supportDaniel Bristot de Oliveira
Add --filter option. This option enables a trace event filtering of the previous -e sys:event argument. This option is available for all current tools. Link: https://lkml.kernel.org/r/509d70b6348d3e5bcbf1f07ab725ce08d063149a.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/trace: Add trace event filter helpersDaniel Bristot de Oliveira
Add a set of helper functions to allow rtla tools to filter events in the trace instance. Link: https://lkml.kernel.org/r/12623b1684684549d53b90f4bf66fae44584fd14.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla: Add --trigger supportDaniel Bristot de Oliveira
Add --trigger option. This option enables a trace event trigger to the previous -e sys:event argument, allowing some advanced tracing options. For instance, in a system with CPUs 2:23 isolated, it is possible to get a stack trace of thread wakeup targeting those CPUs while running osnoise with the following command line: # osnoise top -c 2-23 -a 50 -e sched:sched_wakeup --trigger="stacktrace if target_cpu >= 2" This option is available for all current tools. Link: https://lkml.kernel.org/r/07d2983d5f71261d4da89dbaf02efcad100ab8ee.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/trace: Add trace event trigger helpersDaniel Bristot de Oliveira
Add a set of helper functions to allow rtla tools to trigger event actions in the trace instance. Link: https://lkml.kernel.org/r/e0d31abe879a78a5600b64f904d0dfa8f76e4fbb.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla: Add -e/--event supportDaniel Bristot de Oliveira
Add -e/--event option. This option enables an event in the trace (-t) session. The argument can be a specific event, e.g., -e sched:sched_switch, or all events of a system group, e.g., -e sched. Multiple -e are allowed. It is only active when -t or -a are set. This option is available for all current tools. Link: https://lkml.kernel.org/r/6a3b753be9b1e811953995f7f21a86918ad13390.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/trace: Add trace events helpersDaniel Bristot de Oliveira
Add a set of helper functions to allow the rtla tools to enable additional tracepoints in the trace instance. Link: https://lkml.kernel.org/r/932398b36c1bbaa22c7810d7a40ca9b8c5595b94.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/timerlat: Add the automatic trace optionDaniel Bristot de Oliveira
Add the -a/--auto <arg in us> option. This option sets some commonly used options while debugging the system. It aims to help users produce reports in the field, reducing the number of arguments passed to the tool in the first approach to a problem. It is equivalent to setting osnoise/stop_tracing_total_us and print_stack with the argument, and saving the trace to timerlat_trace.txt file if the trace is stopped automatically. Link: https://lkml.kernel.org/r/92438f7ef132c731f538cebdf77850300afe04a5.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/osnoise: Add the automatic trace optionDaniel Bristot de Oliveira
Add the -a/--auto <arg in us> option. This option sets some commonly used options while debugging the system. It aims to help users produce reports in the field, reducing the number of arguments passed to the tool in the first approach to a problem. It is equivalent to setting osnoise/stop_tracing_us with the argument, setting tracing_thresh to 1 us, and saving the trace to osnoise_trace.txt file if the trace is stopped automatically. Link: https://lkml.kernel.org/r/ef04c961b227eb93a83cd0b54bfca45e1a381b77.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/osnoise: Add an option to set the thresholdDaniel Bristot de Oliveira
Add the -T/--threshold option to set the minimum threshold to be considered a noise to osnoise top and hist commands. Also update the man pages. Link: https://lkml.kernel.org/r/031861200ffdb24a1df4aa72c458706889a20d5d.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15rtla/osnoise: Add support to adjust the tracing_threshDaniel Bristot de Oliveira
osnoise uses the tracing_thresh parameter to define the delta between two reads of the time to be considered a noise. Add support to get and set the tracing_thresh from osnoise tools. Link: https://lkml.kernel.org/r/715ad2a53fd40e41bab8c3f1214c1a94e12fb595.1646247211.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Clark Williams <williams@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25rtla/osnoise: Fix error message when failing to enable trace instanceDaniel Bristot de Oliveira
When a trace instance creation fails, tools are printing: Could not enable -> osnoiser <- tracer for tracing Print the actual (and correct) name of the tracer it fails to enable. Link: https://lkml.kernel.org/r/53ef0582605af91eca14b19dba9fc9febb95d4f9.1645206561.git.bristot@kernel.org Fixes: b1696371d865 ("rtla: Helper functions for rtla") Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25rtla/osnoise: Free params at the exitDaniel Bristot de Oliveira
The variable that stores the parsed command line arguments are not being free()d at the rtla osnoise top exit path. Free params variable before exiting. Link: https://lkml.kernel.org/r/0be31d8259c7c53b98a39769d60cfeecd8421785.1645206561.git.bristot@kernel.org Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode") Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25rtla/hist: Make -E the short version of --entriesDaniel Bristot de Oliveira
Currently, --entries uses -e as the short version in the hist mode of timerlat and osnoise tools. But as -e is already used to enable events on trace sessions by other tools, thus let's keep it available for the same usage for all rtla tools. Make -E the short version of --entries for hist mode on all tools. Note: rtla was merged in this merge window, so rtla was not released yet. Link: https://lkml.kernel.org/r/5dbf0cbe7364d3a05e708926b41a097c59a02b1e.1645206561.git.bristot@kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-08rtla: Fix segmentation fault when failing to enable -tDaniel Bristot de Oliveira
rtla osnoise and timerlat are causing a segmentation fault when running with the --trace option on a kernel that does not support multiple instances. For example: [root@f34 rtla]# rtla osnoise top -t failed to enable the tracer osnoise Could not enable osnoiser tracer for tracing Failed to enable the trace instance Segmentation fault (core dumped) This error happens because the exit code of the tools is trying to destroy the trace instance that failed to be created. Make osnoise_destroy_tool() aware of possible NULL osnoise_tool *, and do not attempt to destroy it. This also simplifies the exit code. Link: https://lkml.kernel.org/r/5660a2b6bf66c2655842360f2d7f6b48db5dba23.1644327249.git.bristot@kernel.org Suggested-by: Steven Rostedt <rostedt@goodmis.org> Fixes: 1eceb2fc2ca5 ("rtla/osnoise: Add osnoise top mode") Fixes: 829a6c0b5698 ("rtla/osnoise: Add the hist mode") Fixes: a828cd18bc4a ("rtla: Add timerlat tool and timelart top mode") Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-04rtla/trace: Error message fixupDaniel Bristot de Oliveira
Use capital and change "tracer %s" to "%s tracer". No functional change. Link: https://lkml.kernel.org/r/361697d27431afefa64c67c323564205385c418d.1643990447.git.bristot@kernel.org Fixes: b1696371d865 ("rtla: Helper functions for rtla") Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-04rtla/utils: Fix session duration parsingDaniel Bristot de Oliveira
Use gmtime to format the duration time. This avoids problems when the system uses local time different of Pisa's Local Time. Link: https://lkml.kernel.org/r/a2f0a37bc006c2561bb8ecd871cd70532b4a9f2d.1643990447.git.bristot@kernel.org Fixes: b1696371d865 ("rtla: Helper functions for rtla") Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-01-13rtla/timerlat: Add timerlat hist modeDaniel Bristot de Oliveira
The rtla hist hist mode displays a histogram of each tracer event occurrence, both for IRQ and timer latencies. The tool also allows many configurations of the timerlat tracer and the collection of the tracer output. Here is one example of the rtla timerlat hist mode output: ---------- %< ---------- [root@alien ~]# rtla timerlat hist -c 0-3 -d 1M # RTLA timerlat histogram # Time unit is microseconds (us) # Duration: 0 00:01:00 Index IRQ-000 Thr-000 IRQ-001 Thr-001 IRQ-002 Thr-002 IRQ-003 Thr-003 0 58572 0 59373 0 58691 0 58895 0 1 1422 57021 628 57241 1310 56160 1102 56805 2 6 2931 0 2695 0 3567 4 3031 3 1 40 0 53 0 260 0 142 4 0 7 0 5 0 6 0 17 5 0 2 0 5 0 7 0 4 6 0 0 0 2 0 1 0 1 8 0 0 0 0 0 0 0 1 over: 0 0 0 0 0 0 0 0 count: 60001 60001 60001 60001 60001 60001 60001 60001 min: 0 1 0 1 0 1 0 1 avg: 0 1 0 1 0 1 0 1 max: 3 5 1 6 1 6 2 8 ---------- >% ---------- Running - rtla timerlat hist --help provides information about the available options. Link: https://lkml.kernel.org/r/7049ed3c46b7d6aceab18ffe7770003dfc4ddceb.1639158831.git.bristot@kernel.org Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: linux-rt-users@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-13rtla: Add timerlat tool and timelart top modeDaniel Bristot de Oliveira
The rtla timerlat tool is an interface for the timerlat tracer. The timerlat tracer dispatches a kernel thread per-cpu. These threads set a periodic timer to wake themselves up and go back to sleep. After the wakeup, they collect and generate useful information for the debugging of operating system timer latency. The timerlat tracer outputs information in two ways. It periodically prints the timer latency at the timer IRQ handler and the Thread handler. It also provides information for each noise via the osnoise tracepoints. The rtla timerlat top mode displays a summary of the periodic output from the timerlat tracer. Here is one example of the rtla timerlat tool output: ---------- %< ---------- [root@alien ~]# rtla timerlat top -c 0-3 -d 1m Timer Latency 0 00:01:00 | IRQ Timer Latency (us) | Thread Timer Latency (us) CPU COUNT | cur min avg max | cur min avg max 0 #60001 | 0 0 0 3 | 1 1 1 6 1 #60001 | 0 0 0 3 | 2 1 1 5 2 #60001 | 0 0 1 6 | 1 1 2 7 3 #60001 | 0 0 0 7 | 1 1 1 11 ---------- >% ---------- Running: # rtla timerlat --help # rtla timerlat top --help provides information about the available options. Link: https://lkml.kernel.org/r/e95032e20c2b88c962195bf7693bb53c9ebcced8.1639158831.git.bristot@kernel.org Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: linux-rt-users@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-13rtla/osnoise: Add the hist modeDaniel Bristot de Oliveira
The rtla osnoise hist tool collects all osnoise:sample_threshold occurrence in a histogram, displaying the results in a user-friendly way. The tool also allows many configurations of the osnoise tracer and the collection of the tracer output. Here is one example of the rtla osnoise hist tool output: ---------- %< ---------- [root@f34 ~]# rtla osnoise hist --bucket-size 10 --entries 100 -c 0-8 -d 1M -r 9000 -P F:1 # RTLA osnoise histogram # Time unit is microseconds (us) # Duration: 0 00:01:00 Index CPU-000 CPU-001 CPU-002 CPU-003 CPU-004 CPU-005 CPU-006 CPU-007 CPU-008 0 430 434 352 455 440 463 467 436 484 10 88 88 92 141 120 100 126 166 100 20 19 7 12 22 8 8 13 13 16 30 6 0 2 0 1 2 2 1 0 50 0 0 0 0 0 0 1 0 0 over: 0 0 0 0 0 0 0 0 0 count: 543 529 458 618 569 573 609 616 600 min: 0 0 0 0 0 0 0 0 0 avg: 0 0 0 0 0 0 0 0 0 max: 30 20 30 20 30 30 50 30 20 ---------- >% ---------- Running - rtla osnoise hist --help provides information about the available options. Link: https://lkml.kernel.org/r/c68060544de89b8b62510ed91c7369f162eb465b.1639158831.git.bristot@kernel.org Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: linux-rt-users@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-13rtla/osnoise: Add osnoise top modeDaniel Bristot de Oliveira
The rtla osnoise tool is an interface for the osnoise tracer. The osnoise tracer dispatches a kernel thread per-cpu. These threads read the time in a loop while with preemption, softirqs and IRQs enabled, thus allowing all the sources of osnoise during its execution. The osnoise threads take note of the entry and exit point of any source of interferences, increasing a per-cpu interference counter. The osnoise tracer also saves an interference counter for each source of interference. The rtla osnoise top mode displays information about the periodic summary from the osnoise tracer. One example of rtla osnoise top output is: [root@alien ~]# rtla osnoise top -c 0-3 -d 1m -q -r 900000 -P F:1 Operating System Noise duration: 0 00:01:00 | time is in us CPU Period Runtime Noise % CPU Aval Max Noise Max Single HW NMI IRQ Softirq Thread 0 #58 52200000 1031 99.99802 91 60 0 0 52285 0 101 1 #59 53100000 5 99.99999 5 5 0 9 53122 0 18 2 #59 53100000 7 99.99998 7 7 0 8 53115 0 18 3 #59 53100000 8274 99.98441 277 23 0 9 53778 0 660 "rtla osnoise top --help" works and provide information about the available options. Link: https://lkml.kernel.org/r/0d796993abf587ae5a170bb8415c49368d4999e1.1639158831.git.bristot@kernel.org Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Ingo Molnar <mingo@redhat.com> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: linux-rt-users@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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