kernel/linux.git/tools/tracing, branch linux-6.9.y

rtla/auto-analysis: Replace \t with spaces

2024-06-21T12:40:36+00:00

commit a40e5e4dd0207485dee75e2b8e860d5853bcc5f7 upstream. When copying timerlat auto-analysis from a terminal to some web pages or chats, the \t are being replaced with a single ' ' or ' ', breaking the output. For example: ## CPU 3 hit stop tracing, analyzing it ## IRQ handler delay: 1.30 us (0.11 %) IRQ latency: 1.90 us Timerlat IRQ duration: 3.00 us (0.24 %) Blocking thread: 1223.16 us (99.00 %) insync:4048 1223.16 us IRQ interference 4.93 us (0.40 %) local_timer:236 4.93 us ------------------------------------------------------------------------ Thread latency: 1235.47 us (100%) Replace \t with spaces to avoid this problem. Link: https://lkml.kernel.org/r/ec7ed2b2809c22ab0dfc8eb7c805ab9cddc4254a.1713968967.git.bristot@kernel.org Cc: stable@vger.kernel.org Cc: Jonathan Corbet Cc: Juri Lelli Fixes: 27e348b221f6 ("rtla/timerlat: Add auto-analysis core") Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Greg Kroah-Hartman

rtla/timerlat: Simplify "no value" printing on top

2024-06-21T12:40:36+00:00

commit 5f0769331a965675cdfec97c09f3f6e875d7c246 upstream. Instead of printing three times the same output, print it only once, reducing lines and being sure that all no values have the same length. It also fixes an extra '\n' when running the with kernel threads, like here: =============== %< ============== Timer Latency 0 00:00:01 | IRQ Timer Latency (us) | Thread Timer Latency (us) CPU COUNT | cur min avg max | cur min avg max 2 #0 | - - - - | 161 161 161 161 3 #0 | - - - - | 161 161 161 161 8 #1 | 54 54 54 54 | - - - -'\n' ---------------|----------------------------------------|--------------------------------------- ALL #1 e0 | 54 54 54 | 161 161 161 =============== %< ============== This '\n' should have been removed with the user-space support that added another '\n' if not running with kernel threads. Link: https://lkml.kernel.org/r/0a4d8085e7cd706733a5dc10a81ca38b82bd4992.1713968967.git.bristot@kernel.org Cc: stable@vger.kernel.org Cc: Jonathan Corbet Cc: Juri Lelli Fixes: cdca4f4e5e8e ("rtla/timerlat_top: Add timerlat user-space support") Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Greg Kroah-Hartman

rtla/timerlat: Fix histogram report when a cpu count is 0

2024-06-16T11:51:07+00:00

commit 01b05fc0e5f3aec443a9a8ffa0022cbca2fd3608 upstream. On short runs it is possible to get no samples on a cpu, like this: # rtla timerlat hist -u -T50 Index IRQ-001 Thr-001 Usr-001 IRQ-002 Thr-002 Usr-002 2 1 0 0 0 0 0 33 0 1 0 0 0 0 36 0 0 1 0 0 0 49 0 0 0 1 0 0 52 0 0 0 0 1 0 over: 0 0 0 0 0 0 count: 1 1 1 1 1 0 min: 2 33 36 49 52 18446744073709551615 avg: 2 33 36 49 52 - max: 2 33 36 49 52 0 rtla timerlat hit stop tracing IRQ handler delay: (exit from idle) 48.21 us (91.09 %) IRQ latency: 49.11 us Timerlat IRQ duration: 2.17 us (4.09 %) Blocking thread: 1.01 us (1.90 %) swapper/2:0 1.01 us ------------------------------------------------------------------------ Thread latency: 52.93 us (100%) Max timerlat IRQ latency from idle: 49.11 us in cpu 2 Note, the value 18446744073709551615 is the same as ~0. Fix this by reporting no results for the min, avg and max if the count is 0. Link: https://lkml.kernel.org/r/20240510190318.44295-1-jkacur@redhat.com Cc: stable@vger.kernel.org Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode") Suggested-by: Daniel Bristot de Oliveria Signed-off-by: John Kacur Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Greg Kroah-Hartman

tools/latency-collector: Fix -Wformat-security compile warns

2024-05-30T07:44:00+00:00

commit df73757cf8f66fa54c4721c53b0916af3c4d9818 upstream. Fix the following -Wformat-security compile warnings adding missing format arguments: latency-collector.c: In function ‘show_available’: latency-collector.c:938:17: warning: format not a string literal and no format arguments [-Wformat-security] 938 | warnx(no_tracer_msg); | ^~~~~ latency-collector.c:943:17: warning: format not a string literal and no format arguments [-Wformat-security] 943 | warnx(no_latency_tr_msg); | ^~~~~ latency-collector.c: In function ‘find_default_tracer’: latency-collector.c:986:25: warning: format not a string literal and no format arguments [-Wformat-security] 986 | errx(EXIT_FAILURE, no_tracer_msg); | ^~~~ latency-collector.c: In function ‘scan_arguments’: latency-collector.c:1881:33: warning: format not a string literal and no format arguments [-Wformat-security] 1881 | errx(EXIT_FAILURE, no_tracer_msg); | ^~~~ Link: https://lore.kernel.org/linux-trace-kernel/20240404011009.32945-1-skhan@linuxfoundation.org Cc: stable@vger.kernel.org Fixes: e23db805da2df ("tracing/tools: Add the latency-collector to tools directory") Signed-off-by: Shuah Khan Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

tools/rtla: Add -U/--user-load option to timerlat

2024-03-20T04:39:06+00:00

The timerlat tracer provides an interface for any application to wait for the timerlat's periodic wakeup. Currently, rtla timerlat uses it to dispatch its user-space workload (-u option). But as the tracer interface is generic, rtla timerlat can also be used to monitor any workload that uses it. For example, a user might place their own workload to wait on the tracer interface, and monitor the results with rtla timerlat. Add the -U option to rtla timerlat top and hist. With this option, rtla timerlat will not dispatch its workload but only setting up the system, waiting for a user to dispatch its workload. The sample code in this patch is an example of python application that loops in the timerlat tracer fd. To use it, dispatch: # rtla timerlat -U In a terminal, then run the python program on another terminal, specifying the CPU to run it. For example, setting on CPU 1: #./timerlat_load.py 1 Then rtla timerlat will start printing the statistics of the ./timerlat_load.py app. An interesting point is that the "Ret user Timer Latency" value is the overall response time of the load. The sample load does a memory copy to exemplify that. The stop tracing options on rtla timerlat works in this setup as well, including auto analysis. Link: https://lkml.kernel.org/r/36e6bcf18fe15c7601048fd4c65aeb193c502cc8.1707229706.git.bristot@kernel.org Cc: Jonathan Corbet Cc: Masami Hiramatsu Signed-off-by: Daniel Bristot de Oliveira

tools/rtla: Use tools/build makefiles to build rtla

2024-03-20T04:39:06+00:00

Use tools/build/ makefiles to build rtla, inheriting the benefits of it. For example, having a proper way to handle dependencies. rtla is built using perf infra-structure when building inside the kernel tree. At this point, rtla diverges from perf in two points: Documentation and tarball generation/build. At the documentation level, rtla is one step ahead, placing the documentation at Documentation/tools/rtla/, using the same build tools as kernel documentation. The idea is to move perf documentation to the same scheme and then share the same makefiles. rtla has a tarball target that the (old) RHEL8 uses. The tarball was kept using a simple standalone makefile for compatibility. The standalone makefile shares most of the code, e.g., flags, with regular buildings. The tarball method was set as deprecated. If necessary, we can make a rtla tarball like perf, which includes the entire tools/build. But this would also require changes in the user side (the directory structure changes, and probably the deps to build the package). Inspired on perf and objtool. Link: https://lkml.kernel.org/r/57563abf2715d22515c0c54a87cff3849eca5d52.1710519524.git.bristot@kernel.org Cc: Arnaldo Carvalho de Melo Cc: Josh Poimboeuf Cc: John Kacur Cc: Namhyung Kim Cc: Jiri Olsa Suggested-by: Linus Torvalds Signed-off-by: Daniel Bristot de Oliveira

tools/tracing: Use tools/build makefiles on latency-collector

2024-03-20T04:39:06+00:00

Use tools/build/ makefiles to build latency-collector, inheriting the benefits of it. For example: Before this patch, a missing tracefs/traceevents headers will result in fail like this: ~/linux/tools/tracing/latency $ make cc -Wall -Wextra -g -O2 -o latency-collector latency-collector.c -lpthread latency-collector.c:26:10: fatal error: tracefs.h: No such file or directory 26 | #include | ^~~~~~~~~~~ compilation terminated. make: *** [Makefile:14: latency-collector] Error 1 Which is not that helpful. After this change it reports: ~/linux/tools/tracing/latency# make Auto-detecting system features: ... libtraceevent: [ OFF ] ... libtracefs: [ OFF ] libtraceevent is missing. Please install libtraceevent-dev/libtraceevent-devel libtracefs is missing. Please install libtracefs-dev/libtracefs-devel Makefile.config:29: *** Please, check the errors above.. Stop. This type of output is common across other tools in tools/ like perf and objtool. Link: https://lkml.kernel.org/r/872420b0880b11304e4ba144a0086c6478c5b469.1710519524.git.bristot@kernel.org Cc: Arnaldo Carvalho de Melo Cc: Josh Poimboeuf Cc: John Kacur Cc: Namhyung Kim Cc: Jiri Olsa Suggested-by: Linus Torvalds Signed-off-by: Daniel Bristot de Oliveira

tools/rtla: Exit with EXIT_SUCCESS when help is invoked

2024-02-12T09:59:09+00:00

Fix rtla so that the following commands exit with 0 when help is invoked rtla osnoise top -h rtla osnoise hist -h rtla timerlat top -h rtla timerlat hist -h Link: https://lore.kernel.org/linux-trace-devel/20240203001607.69703-1-jkacur@redhat.com Cc: stable@vger.kernel.org Fixes: 1eeb6328e8b3 ("rtla/timerlat: Add timerlat hist mode") Signed-off-by: John Kacur Signed-off-by: Daniel Bristot de Oliveira

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