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2025-09-27tools/rtla: Consolidate code between osnoise/timerlat and hist/topCrystal Wood1-2/+2
Currently a lot of code is duplicated between the different rtla tools, making maintenance more difficult, and encouraging divergence such as features that are only implemented for certain tools even though they could be more broadly applicable. Merge the various main() functions into a common run_tool() with an ops struct for tool-specific details. Implement enough support for actions on osnoise to not need to keep the old params->trace_output path. Cc: John Kacur <jkacur@redhat.com> Cc: Costa Shulyupin <costa.shul@redhat.com> Link: https://lore.kernel.org/20250907022325.243930-5-crwood@redhat.com Reviewed-by: Tomas Glozar <tglozar@redhat.com> Signed-off-by: Crystal Wood <crwood@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-09-27tools/rtla: Move top/hist params into common structCrystal Wood1-7/+7
The hist members were very similar between timerlat and top, so just use one common hist struct. output_divisor, quiet, and pretty printing are pretty generic concepts that can go in the main struct even if not every specific tool (currently) uses them. Cc: John Kacur <jkacur@redhat.com> Cc: Costa Shulyupin <costa.shul@redhat.com> Link: https://lore.kernel.org/20250907022325.243930-3-crwood@redhat.com Reviewed-by: Tomas Glozar <tglozar@redhat.com> Signed-off-by: Crystal Wood <crwood@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-09-27tools/rtla: Consolidate common parameters into shared structureCosta Shulyupin1-2/+2
timerlat_params and osnoise_params structures contain 15 identical fields. Introduce a new header common.h and define a common_params structure to consolidate shared fields, reduce code duplication, and enhance maintainability. Cc: John Kacur <jkacur@redhat.com> Link: https://lore.kernel.org/20250907022325.243930-2-crwood@redhat.com Reviewed-by: Tomas Glozar <tglozar@redhat.com> Signed-off-by: Costa Shulyupin <costa.shul@redhat.com> Signed-off-by: Crystal Wood <crwood@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-25rtla/timerlat_bpf: Allow resuming tracingTomas Glozar1-0/+13
Currently, rtla-timerlat BPF program uses a global variable stored in a .bss section to store whether tracing has been stopped. Move the information to a separate map, so that it is easily writable from userspace, and add a function that clears the value, resuming tracing after it has been stopped. Cc: John Kacur <jkacur@redhat.com> Cc: Luis Goncalves <lgoncalv@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Chang Yin <cyin@redhat.com> Cc: Costa Shulyupin <costa.shul@redhat.com> Cc: Crystal Wood <crwood@redhat.com> Cc: Gabriele Monaco <gmonaco@redhat.com> Link: https://lore.kernel.org/20250626123405.1496931-4-tglozar@redhat.com Signed-off-by: Tomas Glozar <tglozar@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-05-07rtla: Define _GNU_SOURCE in timerlat_bpf.cTomas Glozar1-0/+1
Newer versions of glibc include a definition of struct sched_attr in bits/sched.h (included through sched.h which is included by rtla). Commit 0eecee340672 ("tools/rtla: fix collision with glibc sched_attr/sched_set_attr") has modified the definition of struct sched_attr in utils.h, so that it is only applied with older versions of glibc that do not define it, in order to prevent build failure. The definition in bits/sched.h depends on _GNU_SOURCE. timerlat_bpf.c does not define _GNU_SOURCE, making it fall back to the definition in utils.h. The latter has two fields less, leading to shifted offsets of struct timerlat_params in timerlat_bpf_init. Because of the shift, timerlat_bpf_init incorrectly reads params->entries as 0 for timerlat-hist and disables the creation of histogram maps, causing breakage in BPF sample collection mode: $ rtla timerlat hist -d 1s Error pulling BPF data Fix the issue by also defining _GNU_SOURCE in timerlat_bpf.c. Cc: John Kacur <jkacur@redhat.com> Cc: Luis Goncalves <lgoncalv@redhat.com> Link: https://lore.kernel.org/20250430144651.621766-1-tglozar@redhat.com Fixes: e34293ddcebd ("rtla/timerlat: Add BPF skeleton to collect samples") Signed-off-by: Tomas Glozar <tglozar@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-03-04rtla/timerlat: Add BPF skeleton to collect samplesTomas Glozar1-0/+166
Add BPF program that attaches to the osnoise:timerlat_sample tracepoint and collects both the summary and the histogram (if requested) into BPF maps (one map of each kind per context). The program is designed to be used for both timerlat-top and timerlat-hist. If using with timerlat-top, the "entries" parameter is set to zero, which prevents the BPF program from recording histogram entries. In that case, the maps for histograms do not have to be created, as the BPF verifier will identify the code using them as unreachable. An IRQ or thread latency threshold might be supplied to stop recording if hit, similar to the timerlat tracer threshold, which stops ftrace tracing if hit. A BPF ringbuffer is used to signal threshold overflow to userspace. In aa-only mode, this is the only function of the BPF program. Cc: John Kacur <jkacur@redhat.com> Cc: Luis Goncalves <lgoncalv@redhat.com> Cc: Gabriele Monaco <gmonaco@redhat.com> Cc: Clark Williams <williams@redhat.com> Link: https://lore.kernel.org/20250218145859.27762-5-tglozar@redhat.com Signed-off-by: Tomas Glozar <tglozar@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>