kernel/linux.git/tools/tracing/rtla/src/utils.c, branch v6.19.11

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: Define __NR_sched_setattr for LoongArch

2025-05-07T20:35:31+00:00

When executing "make -C tools/tracing/rtla" on LoongArch, there exists the following error: src/utils.c:237:24: error: '__NR_sched_setattr' undeclared Just define __NR_sched_setattr for LoongArch if not exist. Link: https://lore.kernel.org/20250422074917.25771-1-yangtiezhu@loongson.cn Reported-by: Haiyong Sun Signed-off-by: Tiezhu Yang Signed-off-by: Steven Rostedt (Google)

rtla/utils: Add idle state disabling via libcpupower

2024-10-17T21:13:15+00:00

Add functions to utils.c to disable idle states through functions of libcpupower. This will serve as the basis for disabling idle states per cpu when running timerlat. Link: https://lore.kernel.org/20241017140914.3200454-4-tglozar@redhat.com Signed-off-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

tools/rtla: fix collision with glibc sched_attr/sched_set_attr

2024-10-11T00:31:48+00:00

glibc commit 21571ca0d703 ("Linux: Add the sched_setattr and sched_getattr functions") now also provides 'struct sched_attr' and sched_setattr() which collide with the ones from rtla. In file included from src/trace.c:11: src/utils.h:49:8: error: redefinition of ‘struct sched_attr’ 49 | struct sched_attr { | ^~~~~~~~~~ In file included from /usr/include/bits/sched.h:60, from /usr/include/sched.h:43, from /usr/include/tracefs/tracefs.h:10, from src/trace.c:4: /usr/include/linux/sched/types.h:98:8: note: originally defined here 98 | struct sched_attr { | ^~~~~~~~~~ Define 'struct sched_attr' conditionally, similar to what strace did: https://lore.kernel.org/all/20240930222913.3981407-1-raj.khem@gmail.com/ and rename rtla's version of sched_setattr() to avoid collision. Link: https://lore.kernel.org/8088f66a7a57c1b209cd8ae0ae7c336a7f8c930d.1728572865.git.jstancek@redhat.com Signed-off-by: Jan Stancek Signed-off-by: Steven Rostedt (Google)

tools/rtla: drop __NR_sched_getattr

2024-10-11T00:30:58+00:00

It's not used since commit 084ce16df0f0 ("tools/rtla: Remove unused sched_getattr() function"). Link: https://lore.kernel.org/c355dc9ad23470098d6a8d0f31fbd702551c9ea8.1728552769.git.jstancek@redhat.com Signed-off-by: Jan Stancek Reviewed-by: Tomas Glozar Signed-off-by: Steven Rostedt (Google)

tools/rtla: Replace setting prio with nice for SCHED_OTHER

2024-02-12T09:56:36+00:00

Since the sched_priority for SCHED_OTHER is always 0, it makes no sence to set it. Setting nice for SCHED_OTHER seems more meaningful. Link: https://lkml.kernel.org/r/20240207065142.1753909-1-limingming3@lixiang.com Cc: stable@vger.kernel.org Fixes: b1696371d865 ("rtla: Helper functions for rtla") Signed-off-by: limingming3 Signed-off-by: Daniel Bristot de Oliveira

tools/rtla: Remove unused sched_getattr() function

2024-02-12T08:57:37+00:00

Clang is reporting: $ make HOSTCC=clang CC=clang LLVM_IAS=1 [...] clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions -fstack-protector-strong -fasynchronous-unwind-tables -fstack-clash-protection -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS $(pkg-config --cflags libtracefs) -c -o src/utils.o src/utils.c src/utils.c:241:19: warning: unused function 'sched_getattr' [-Wunused-function] 241 | static inline int sched_getattr(pid_t pid, struct sched_attr *attr, | ^~~~~~~~~~~~~ 1 warning generated. Which is correct, so remove the unused function. Link: https://lkml.kernel.org/r/eaed7ba122c4ae88ce71277c824ef41cbf789385.1707217097.git.bristot@kernel.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Bill Wendling Cc: Justin Stitt Cc: Donald Zickus Fixes: b1696371d865 ("rtla: Helper functions for rtla") Signed-off-by: Daniel Bristot de Oliveira

tools/rtla: Fix clang warning about mount_point var size

2024-02-12T08:57:14+00:00

clang is reporting this warning: $ make HOSTCC=clang CC=clang LLVM_IAS=1 [...] clang -O -g -DVERSION=\"6.8.0-rc3\" -flto=auto -fexceptions -fstack-protector-strong -fasynchronous-unwind-tables -fstack-clash-protection -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS $(pkg-config --cflags libtracefs) -c -o src/utils.o src/utils.c src/utils.c:548:66: warning: 'fscanf' may overflow; destination buffer in argument 3 has size 1024, but the corresponding specifier may require size 1025 [-Wfortify-source] 548 | while (fscanf(fp, "%*s %" STR(MAX_PATH) "s %99s %*s %*d %*d\n", mount_point, type) == 2) { | ^ Increase mount_point variable size to MAX_PATH+1 to avoid the overflow. Link: https://lkml.kernel.org/r/1b46712e93a2f4153909514a36016959dcc4021c.1707217097.git.bristot@kernel.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Bill Wendling Cc: Justin Stitt Cc: Donald Zickus Fixes: a957cbc02531 ("rtla: Add -C cgroup support") Signed-off-by: Daniel Bristot de Oliveira

rtla: Fix uninitialized variable found

2023-10-30T18:00:12+00:00

Variable found is not being initialized, in the case where the desired mount is not found the variable contains garbage. Fix this by initializing it to zero. Link: https://lore.kernel.org/all/20230727150117.627730-1-colin.i.king@gmail.com/ Fixes: a957cbc02531 ("rtla: Add -C cgroup support") Signed-off-by: Colin Ian King Signed-off-by: Daniel Bristot de Oliveira