kernel/linux.git/tools/tracing/rtla/src/utils.h, branch v7.1-rc5

rtla: Add str_has_prefix() helper function

2026-03-11T14:29:50+00:00

Add a str_has_prefix() helper function that tests whether a string starts with a given prefix. This function provides a cleaner interface for prefix matching compared to using strncmp() with strlen() directly. The function returns a boolean value indicating whether the string starts with the specified prefix. This helper will be used in subsequent changes to simplify prefix matching code throughout rtla. Also add the missing string.h include which is needed for the strlen() and strncmp() functions used by str_has_prefix() and the existing strncmp_static() macro. Signed-off-by: Wander Lairson Costa Link: https://lore.kernel.org/r/20260309195040.1019085-11-wander@redhat.com Signed-off-by: Tomas Glozar

rtla/actions: Simplify argument parsing

2026-03-10T09:32:37+00:00

The actions_parse() function uses open-coded logic to extract arguments from a string. This includes manual length checks and strncmp() calls, which can be verbose and error-prone. To simplify and improve the robustness of argument parsing, introduce a new extract_arg() helper macro. This macro extracts the value from a "key=value" pair, making the code more concise and readable. Also, introduce STRING_LENGTH() and strncmp_static() macros to perform compile-time calculations of string lengths and safer string comparisons. Refactor actions_parse() to use these new helpers, resulting in cleaner and more maintainable code. Signed-off-by: Wander Lairson Costa Link: https://lore.kernel.org/r/20260309195040.1019085-4-wander@redhat.com Signed-off-by: Tomas Glozar

rtla: Exit on memory allocation failures during initialization

2026-03-10T09:32:37+00:00

Most memory allocations in rtla happen during early initialization before any resources are acquired that would require cleanup. In these cases, propagating allocation errors just adds complexity without any benefit. There's nothing to clean up, and the program must exit anyway. This patch introduces fatal allocation wrappers (calloc_fatal, reallocarray_fatal, strdup_fatal) that call fatal() on allocation failure. These wrappers simplify the code by eliminating unnecessary error propagation paths. The patch converts early allocations to use these wrappers in actions_init() and related action functions, osnoise_context_alloc() and osnoise_init_tool(), trace_instance_init() and trace event functions, and parameter structure allocations in main functions. This simplifies the code while maintaining the same behavior: immediate exit on allocation failure during initialization. Allocations that require cleanup, such as those in histogram allocation functions with goto cleanup paths, are left unchanged and continue to return errors. Signed-off-by: Wander Lairson Costa Link: https://lore.kernel.org/r/20260309195040.1019085-2-wander@redhat.com Signed-off-by: Tomas Glozar

rtla/timerlat: Add --stack-format option

2026-03-04T14:51:56+00:00

In the current implementation, the auto-analysis code for printing the stack captured in the tracefs buffer of the aa instance stops at the first encountered address that cannot be resolved into a function symbol. This is not always the desired behavior on all platforms; sometimes, there might be resolvable entries after unresolvable ones, and sometimes, the user might want to inspect the raw pointers for the unresolvable entries. Add a new option, --stack-format, with three values: - truncate: stop at first unresolvable entry. This is the current behavior, and is kept as the default. - skip: skip unresolvable entries, but do not stop on them. - full: print all entries, including unresolvable ones. To make this work, the "size" field of the stack entry is now also read and used as the maximum number of entries to print, capped at 64, since that is the fixed length of the "caller" field. Link: https://lore.kernel.org/r/20260119115222.744150-1-tglozar@redhat.com Signed-off-by: Tomas Glozar

rtla: Use standard exit codes for result enum

2026-01-07T14:57:55+00:00

The result enum defines custom values for PASSED, ERROR, and FAILED. These values correspond to standard exit codes EXIT_SUCCESS and EXIT_FAILURE. Update the enum to use the standard macros EXIT_SUCCESS and EXIT_FAILURE to improve readability and adherence to standard C practices. The FAILED value is implicitly assigned EXIT_FAILURE + 1, so there is no need to assign an explicit value. Signed-off-by: Wander Lairson Costa Link: https://lore.kernel.org/r/20260106133655.249887-9-wander@redhat.com Signed-off-by: Tomas Glozar

rtla: Replace atoi() with a robust strtoi()

2026-01-07T14:57:55+00:00

The atoi() function does not perform error checking, which can lead to undefined behavior when parsing invalid or out-of-range strings. This can cause issues when parsing user-provided numerical inputs, such as signal numbers, PIDs, or CPU lists. To address this, introduce a new strtoi() helper function that safely converts a string to an integer. This function validates the input and checks for overflows, returning a negative value on failure. Replace all calls to atoi() with the new strtoi() function and add proper error handling to make the parsing more robust and prevent potential issues. Signed-off-by: Wander Lairson Costa Link: https://lore.kernel.org/r/20260106133655.249887-5-wander@redhat.com Signed-off-by: Tomas Glozar

tools/rtla: Remove unused function declarations

2026-01-06T09:11:59+00:00

Historically four function declarations remain orphaned or duplicated. Remove them to keep the source clean. Signed-off-by: Costa Shulyupin Link: https://lore.kernel.org/r/20251012071133.290225-1-costa.shul@redhat.com Signed-off-by: Tomas Glozar

rtla: Fix -C/--cgroup interface

2025-11-21T09:30:27+00:00

Currently, user can only specify cgroup to the tracer's thread the following ways: `-C[cgroup]` `-C[=cgroup]` `--cgroup[=cgroup]` If user tries to specify cgroup as `-C [cgroup]` or `--cgroup [cgroup]`, the parser silently fails and rtla's cgroup is used for the tracer threads. To make interface more user-friendly, allow user to specify cgroup in the aforementioned way, i.e. `-C [cgroup]` and `--cgroup [cgroup]`. Refactor identical logic between -t/--trace and -C/--cgroup into a common function. Change documentation to reflect this user interface change. Fixes: a957cbc02531 ("rtla: Add -C cgroup support") Signed-off-by: Ivan Pravdin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/16132f1565cf5142b5fbd179975be370b529ced7.1762186418.git.ipravdin.official@gmail.com [ use capital letter in subject, as required by tracing subsystem ] Signed-off-by: Tomas Glozar

tools/rtla: Add fatal() and replace error handling pattern

2025-11-21T09:30:27+00:00

The code contains some technical debt in error handling, which complicates the consolidation of duplicated code. Introduce an fatal() function to replace the common pattern of err_msg() followed by exit(EXIT_FAILURE), reducing the length of an already long function. Further patches using fatal() follow. Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Link: https://lore.kernel.org/r/20251011082738.173670-2-costa.shul@redhat.com Signed-off-by: Tomas Glozar

rtla: Set distinctive exit value for failed tests

2025-05-07T19:36:19+00:00

A test is considered failed when a sample trace exceeds the threshold. Failed tests return the same exit code as passed tests, requiring test frameworks to determine the result by searching for "hit stop tracing" in the output. Assign a distinct exit code for failed tests to enable the use of shell expressions and seamless integration with testing frameworks without the need to parse output. Add enum type for return value. Update `make check`. Cc: Daniel Bristot de Oliveira Cc: John Kacur Cc: "Luis Claudio R. Goncalves" Cc: Eder Zulian Cc: Dan Carpenter Cc: Jan Stancek Link: https://lore.kernel.org/20250417185757.2194541-1-costa.shul@redhat.com Signed-off-by: Costa Shulyupin Reviewed-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)