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2023-08-16selftests/ftrace: Add a basic testcase for snapshotZheng Yejian1-0/+31
This testcase is constrived to reproduce a problem that the cpu buffers become unavailable which is due to 'record_disabled' of array_buffer and max_buffer being messed up. Local test result after bugfix: # ./ftracetest test.d/00basic/snapshot1.tc === Ftrace unit tests === [1] Snapshot and tracing_cpumask [PASS] [2] (instance) Snapshot and tracing_cpumask [PASS] # of passed: 2 # of failed: 0 # of unresolved: 0 # of untested: 0 # of unsupported: 0 # of xfailed: 0 # of undefined(test bug): 0 Link: https://lkml.kernel.org/r/20230805033816.3284594-3-zhengyejian1@huawei.com Cc: <mhiramat@kernel.org> Cc: <vnagarnaik@google.com> Cc: <shuah@kernel.org> Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-26selftests/ftrace: Fix to check fprobe event eneblementMasami Hiramatsu (Google)1-1/+1
Fix to check the availability of fprobe and kprobes for add_remove_btfarg.tc. Only if both kprobe and fprobe are not supported, it should return "unsupported". Link: https://lore.kernel.org/all/169024904889.395371.17998733386857387118.stgit@devnote2/ Fixes: 4231f30fcc34 ("selftests/ftrace: Add BTF arguments test cases") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-30Merge tag 'probes-v6.5' of ↵Linus Torvalds7-1/+338
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: - fprobe: Pass return address to the fprobe entry/exit callbacks so that the callbacks don't need to analyze pt_regs/stack to find the function return address. - kprobe events: cleanup usage of TPARG_FL_FENTRY and TPARG_FL_RETURN flags so that those are not set at once. - fprobe events: - Add a new fprobe events for tracing arbitrary function entry and exit as a trace event. - Add a new tracepoint events for tracing raw tracepoint as a trace event. This allows user to trace non user-exposed tracepoints. - Move eprobe's event parser code into probe event common file. - Introduce BTF (BPF type format) support to kernel probe (kprobe, fprobe and tracepoint probe) events so that user can specify traced function arguments by name. This also applies the type of argument when fetching the argument. - Introduce '$arg*' wildcard support if BTF is available. This expands the '$arg*' meta argument to all function argument automatically. - Check the return value types by BTF. If the function returns 'void', '$retval' is rejected. - Add some selftest script for fprobe events, tracepoint events and BTF support. - Update documentation about the fprobe events. - Some fixes for above features, document and selftests. - selftests for ftrace (in addition to the new fprobe events): - Add a test case for multiple consecutive probes in a function which checks if ftrace based kprobe, optimized kprobe and normal kprobe can be defined in the same target function. - Add a test case for optimized probe, which checks whether kprobe can be optimized or not. * tag 'probes-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Fix tracepoint event with $arg* to fetch correct argument Documentation: Fix typo of reference file name tracing/probes: Fix to return NULL and keep using current argc selftests/ftrace: Add new test case which checks for optimized probes selftests/ftrace: Add new test case which adds multiple consecutive probes in a function Documentation: tracing/probes: Add fprobe event tracing document selftests/ftrace: Add BTF arguments test cases selftests/ftrace: Add tracepoint probe test case tracing/probes: Add BTF retval type support tracing/probes: Add $arg* meta argument for all function args tracing/probes: Support function parameters if BTF is available tracing/probes: Move event parameter fetching code to common parser tracing/probes: Add tracepoint support on fprobe_events selftests/ftrace: Add fprobe related testcases tracing/probes: Add fprobe events for tracing function entry and exit. tracing/probes: Avoid setting TPARG_FL_FENTRY and TPARG_FL_RETURN fprobe: Pass return address to the handlers
2023-06-30Merge tag 'trace-v6.5' of ↵Linus Torvalds1-0/+44
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - Add new feature to have function graph tracer record the return value. Adds a new option: funcgraph-retval ; when set, will show the return value of a function in the function graph tracer. - Also add the option: funcgraph-retval-hex where if it is not set, and the return value is an error code, then it will return the decimal of the error code, otherwise it still reports the hex value. - Add the file /sys/kernel/tracing/osnoise/per_cpu/cpu<cpu>/timerlat_fd That when a application opens it, it becomes the task that the timer lat tracer traces. The application can also read this file to find out how it's being interrupted. - Add the file /sys/kernel/tracing/available_filter_functions_addrs that works just the same as available_filter_functions but also shows the addresses of the functions like kallsyms, except that it gives the address of where the fentry/mcount jump/nop is. This is used by BPF to make it easier to attach BPF programs to ftrace hooks. - Replace strlcpy with strscpy in the tracing boot code. * tag 'trace-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Fix warnings when building htmldocs for function graph retval riscv: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL tracing/boot: Replace strlcpy with strscpy tracing/timerlat: Add user-space interface tracing/osnoise: Skip running osnoise if all instances are off tracing/osnoise: Switch from PF_NO_SETAFFINITY to migrate_disable ftrace: Show all functions with addresses in available_filter_functions_addrs selftests/ftrace: Add funcgraph-retval test case LoongArch: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL x86/ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL arm64: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL tracing: Add documentation for funcgraph-retval and funcgraph-retval-hex function_graph: Support recording and printing the return value of function fgraph: Add declaration of "struct fgraph_ret_regs"
2023-06-23selftests/ftrace: Add new test case which checks for optimized probesAkanksha J N1-0/+34
Add new test case kprobe_opt_types.tc which enables and checks if each probe has been optimized in order to test potential issues with optimized probes. The '|| continue' is added with the echo statement to ignore errors that are caused by trying to add kprobes to non probeable lines and continue with the test. Link: Link: https://lore.kernel.org/linux-trace-kernel/20230428163842.95118-3-akanksha@linux.ibm.com Signed-off-by: Akanksha J N <akanksha@linux.ibm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-20selftests/ftrace: Add funcgraph-retval test caseDonglin Peng1-0/+44
Add a test case for the funcgraph-retval and funcgraph-retval-hex trace options. Link: https://lkml.kernel.org/r/9fedbd25e63f012cade5dad13be21225fec2fb5d.1680954589.git.pengdonglin@sangfor.com.cn Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-12selftests/ftace: Fix KTAP output orderingMark Brown1-1/+1
The KTAP parser I used to test the KTAP output for ftracetest was overly robust and did not notice that the test number and pass/fail result were reversed. Fix this. Fixes: dbcf76390eb9 ("selftests/ftrace: Improve integration with kselftest runner") Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-06-12selftests/ftrace: Add new test case which checks for optimized probesAkanksha J N1-0/+34
Add new test case kprobe_opt_types.tc which enables and checks if each probe has been optimized in order to test potential issues with optimized probes. The '|| continue' is added with the echo statement to ignore errors that are caused by trying to add kprobes to non probeable lines and continue with the test. Signed-off-by: Akanksha J N <akanksha@linux.ibm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-06-06selftests/ftrace: Add new test case which adds multiple consecutive probes ↵Akanksha J N1-0/+19
in a function Commit 97f88a3d723162 ("powerpc/kprobes: Fix null pointer reference in arch_prepare_kprobe()") fixed a recent kernel oops that was caused as ftrace-based kprobe does not generate kprobe::ainsn::insn and it gets set to NULL. Add new test case kprobe_insn_boundary.tc which adds a kprobe at every byte within $FUNCTION_FORK up to an offset of 256 bytes, to be able to test potential issues with kprobes on successive instructions. The '|| continue' is added with the echo statement to ignore errors that are caused by trying to add kprobes to non probeable lines and continue with the test. Link: https://lore.kernel.org/linux-trace-kernel/20230428163842.95118-2-akanksha@linux.ibm.com Signed-off-by: Akanksha J N <akanksha@linux.ibm.com> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-06selftests/ftrace: Add BTF arguments test casesMasami Hiramatsu (Google)3-0/+86
Add test cases to check the BTF arguments correctly supported. Link: https://lore.kernel.org/all/168507478292.913472.25631899274942311.stgit@mhiramat.roam.corp.google.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-06selftests/ftrace: Add tracepoint probe test caseMasami Hiramatsu (Google)4-2/+111
Add test cases for tracepoint probe events. Link: https://lore.kernel.org/all/168507477214.913472.11218388626709005588.stgit@mhiramat.roam.corp.google.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-06selftests/ftrace: Add fprobe related testcasesMasami Hiramatsu (Google)2-0/+123
Add syntax error testcase and add-remove testcase for fprobe events. This ensures that the fprobe events can be added/removed and parser handles syntax errors correctly. Link: https://lore.kernel.org/all/168507470812.913472.7489900116963294042.stgit@mhiramat.roam.corp.google.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-06tracing/probes: Add fprobe events for tracing function entry and exit.Masami Hiramatsu (Google)1-1/+1
Add fprobe events for tracing function entry and exit instead of kprobe events. With this change, we can continue to trace function entry/exit even if the CONFIG_KPROBES_ON_FTRACE is not available. Since CONFIG_KPROBES_ON_FTRACE requires the CONFIG_DYNAMIC_FTRACE_WITH_REGS, it is not available if the architecture only supports CONFIG_DYNAMIC_FTRACE_WITH_ARGS. And that means kprobe events can not probe function entry/exit effectively on such architecture. But this can be solved if the dynamic events supports fprobe events. The fprobe event is a new dynamic events which is only for the function (symbol) entry and exit. This event accepts non register fetch arguments so that user can trace the function arguments and return values. The fprobe events syntax is here; f[:[GRP/][EVENT]] FUNCTION [FETCHARGS] f[MAXACTIVE][:[GRP/][EVENT]] FUNCTION%return [FETCHARGS] E.g. # echo 'f vfs_read $arg1' >> dynamic_events # echo 'f vfs_read%return $retval' >> dynamic_events # cat dynamic_events f:fprobes/vfs_read__entry vfs_read arg1=$arg1 f:fprobes/vfs_read__exit vfs_read%return arg1=$retval # echo 1 > events/fprobes/enable # head -n 20 trace | tail # TASK-PID CPU# ||||| TIMESTAMP FUNCTION # | | | ||||| | | sh-142 [005] ...1. 448.386420: vfs_read__entry: (vfs_read+0x4/0x340) arg1=0xffff888007f7c540 sh-142 [005] ..... 448.386436: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=0x1 sh-142 [005] ...1. 448.386451: vfs_read__entry: (vfs_read+0x4/0x340) arg1=0xffff888007f7c540 sh-142 [005] ..... 448.386458: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=0x1 sh-142 [005] ...1. 448.386469: vfs_read__entry: (vfs_read+0x4/0x340) arg1=0xffff888007f7c540 sh-142 [005] ..... 448.386476: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=0x1 sh-142 [005] ...1. 448.602073: vfs_read__entry: (vfs_read+0x4/0x340) arg1=0xffff888007f7c540 sh-142 [005] ..... 448.602089: vfs_read__exit: (ksys_read+0x75/0x100 <- vfs_read) arg1=0x1 Link: https://lore.kernel.org/all/168507469754.913472.6112857614708350210.stgit@mhiramat.roam.corp.google.com/ Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/all/202302011530.7vm4O8Ro-lkp@intel.com/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-06-03Merge tag 'probes-fixes-6.4-rc4' of ↵Linus Torvalds1-18/+27
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes fixes from Masami Hiramatsu: - Return NULL if the trace_probe list on trace_probe_event is empty - selftests/ftrace: Choose testing symbol name for filtering feature from sample data instead of fixed symbol * tag 'probes-fixes-6.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: selftests/ftrace: Choose target function for filter test from samples tracing/probe: trace_probe_primary_from_call(): checked list_first_entry
2023-06-03selftests/ftrace: Choose target function for filter test from samplesMasami Hiramatsu (Google)1-18/+27
Since the event-filter-function.tc expects the 'exit_mmap()' directly calls 'kmem_cache_free()', this is vulnerable to code modifications. Choose the target function for the filter test from the sample event data so that it can keep test running correctly even if the caller function name will be changed. Link: https://lore.kernel.org/linux-trace-kernel/167919441260.1922645.18355804179347364057.stgit@mhiramat.roam.corp.google.com/ Link: https://lore.kernel.org/all/CA+G9fYtF-XEKi9YNGgR=Kf==7iRb2FrmEC7qtwAeQbfyah-UhA@mail.gmail.com/ Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Fixes: 7f09d639b8c4 ("tracing/selftests: Add test for event filtering on function name") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-23tracing/selftests: Update synthetic event selftest to use common_stacktraceSteven Rostedt (Google)2-3/+26
With the rename of the stacktrace field to common_stacktrace, update the selftests to reflect this change. Copy the current selftest to test the backward compatibility "stacktrace" keyword. Also the "requires" of that test was incorrect, so it would never actually ran before. That is fixed now. Link: https://lore.kernel.org/linux-trace-kernel/20230523225402.55951f2f@rorschach.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-05-08selftests/ftrace: Improve integration with kselftest runnerMark Brown3-4/+70
The ftrace selftests do not currently produce KTAP output, they produce a custom format much nicer for human consumption. This means that when run in automated test systems we just get a single result for the suite as a whole rather than recording results for individual test cases, making it harder to look at the test data and masking things like inappropriate skips. Address this by adding support for KTAP output to the ftracetest script and providing a trivial wrapper which will be invoked by the kselftest runner to generate output in this format by default, users using ftracetest directly will continue to get the existing output. This is not the most elegant solution but it is simple and effective. I did consider implementing this by post processing the existing output format but that felt more complex and likely to result in all output being lost if something goes seriously wrong during the run which would not be helpful. I did also consider just writing a separate runner script but there's enough going on with things like the signal handling for that to seem like it would be duplicating too much. Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Tested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-03-01Merge tag 'loongarch-6.3' of ↵Linus Torvalds2-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Make -mstrict-align configurable - Add kernel relocation and KASLR support - Add single kernel image implementation for kdump - Add hardware breakpoints/watchpoints support - Add kprobes/kretprobes/kprobes_on_ftrace support - Add LoongArch support for some selftests. * tag 'loongarch-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (23 commits) selftests/ftrace: Add LoongArch kprobe args string tests support selftests/seccomp: Add LoongArch selftesting support tools: Add LoongArch build infrastructure samples/kprobes: Add LoongArch support LoongArch: Mark some assembler symbols as non-kprobe-able LoongArch: Add kprobes on ftrace support LoongArch: Add kretprobes support LoongArch: Add kprobes support LoongArch: Simulate branch and PC* instructions LoongArch: ptrace: Add hardware single step support LoongArch: ptrace: Add function argument access API LoongArch: ptrace: Expose hardware breakpoints to debuggers LoongArch: Add hardware breakpoints/watchpoints support LoongArch: kdump: Add crashkernel=YM handling LoongArch: kdump: Add single kernel image implementation LoongArch: Add support for kernel address space layout randomization (KASLR) LoongArch: Add support for kernel relocation LoongArch: Add la_abs macro implementation LoongArch: Add JUMP_VIRT_ADDR macro implementation to avoid using la.abs LoongArch: Use la.pcrel instead of la.abs when it's trivially possible ...
2023-02-25selftests/ftrace: Add LoongArch kprobe args string tests supportQing Zhang2-0/+7
Before: [5] Kprobe event string type argument [UNTESTED] [7] Kprobe event argument syntax [UNTESTED] After: [5] Kprobe event string type argument [PASS] [7] Kprobe event argument syntax [PASS] Signed-off-by: Qing Zhang <zhangqing@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-23Merge tag 'probes-v6.3' of ↵Linus Torvalds3-2/+51
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull kprobes updates from Masami Hiramatsu: - Skip negative return code check for snprintf in eprobe - Add recursive call test cases for kprobe unit test - Add 'char' type to probe events to show it as the character instead of value - Update kselftest kprobe-event testcase to ignore '__pfx_' symbols - Fix kselftest to check filter on eprobe event correctly - Add filter on eprobe to the README file in tracefs - Fix optprobes to check whether there is 'under unoptimizing' optprobe when optimizing another kprobe correctly - Fix optprobe to check whether there is 'under unoptimizing' optprobe when fetching the original instruction correctly - Fix optprobe to free 'forcibly unoptimized' optprobe correctly * tag 'probes-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/eprobe: no need to check for negative ret value for snprintf test_kprobes: Add recursed kprobe test case tracing/probe: add a char type to show the character value of traced arguments selftests/ftrace: Fix probepoint testcase to ignore __pfx_* symbols selftests/ftrace: Fix eprobe syntax test case to check filter support tracing/eprobe: Fix to add filter on eprobe description in README file x86/kprobes: Fix arch_check_optimized_kprobe check within optimized_kprobe range x86/kprobes: Fix __recover_optprobed_insn check optimizing logic kprobes: Fix to handle forcibly unoptimized kprobes on freeing_list
2023-02-23Merge tag 'trace-v6.3' of ↵Linus Torvalds3-0/+88
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - Add function names as a way to filter function addresses - Add sample module to test ftrace ops and dynamic trampolines - Allow stack traces to be passed from beginning event to end event for synthetic events. This will allow seeing the stack trace of when a task is scheduled out and recorded when it gets scheduled back in. - Add trace event helper __get_buf() to use as a temporary buffer when printing out trace event output. - Add kernel command line to create trace instances on boot up. - Add enabling of events to instances created at boot up. - Add trace_array_puts() to write into instances. - Allow boot instances to take a snapshot at the end of boot up. - Allow live patch modules to include trace events - Minor fixes and clean ups * tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (31 commits) tracing: Remove unnecessary NULL assignment tracepoint: Allow livepatch module add trace event tracing: Always use canonical ftrace path tracing/histogram: Fix stacktrace histogram Documententation tracing/histogram: Fix stacktrace key tracing/histogram: Fix a few problems with stacktrace variable printing tracing: Add BUILD_BUG() to make sure stacktrace fits in strings tracing/histogram: Don't use strlen to find length of stacktrace variables tracing: Allow boot instances to have snapshot buffers tracing: Add trace_array_puts() to write into instance tracing: Add enabling of events to boot instances tracing: Add creation of instances at boot command line tracing: Fix trace_event_raw_event_synth() if else statement samples: ftrace: Make some global variables static ftrace: sample: avoid open-coded 64-bit division samples: ftrace: Include the nospec-branch.h only for x86 tracing: Acquire buffer from temparary trace sequence tracing/histogram: Wrap remaining shell snippets in code blocks tracing/osnoise: No need for schedule_hrtimeout range bpf/tracing: Use stage6 of tracing to not duplicate macros ...
2023-02-21tracing/probe: add a char type to show the character value of traced argumentsDonglin Peng1-0/+47
There are scenes that we want to show the character value of traced arguments other than a decimal or hexadecimal or string value for debug convinience. I add a new type named 'char' to do it and a new test case file named 'kprobe_args_char.tc' to do selftest for char type. For example: The to be traced function is 'void demo_func(char type, char *name);', we can add a kprobe event as follows to show argument values as we want: echo 'p:myprobe demo_func $arg1:char +0($arg2):char[5]' > kprobe_events we will get the following trace log: ... myprobe: (demo_func+0x0/0x29) arg1='A' arg2={'b','p','f','1',''} Link: https://lore.kernel.org/all/20221219110613.367098-1-dolinux.peng@gmail.com/ Signed-off-by: Donglin Peng <dolinux.peng@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-02-21selftests/ftrace: Fix probepoint testcase to ignore __pfx_* symbolsMasami Hiramatsu (Google)1-1/+1
Fix kprobe probepoint testcase to ignore __pfx_* prefix symbols. Those are introduced by commit b341b20d648b ("x86: Add prefix symbols for function padding") for identifying PADDING_BYTES of NOPs. Since kprobe events can not probe these prefix symbols, this testcase has to skip those symbols. Link: https://lore.kernel.org/all/167309835609.640500.9664678940260305746.stgit@devnote3/ Fixes: b341b20d648b ("x86: Add prefix symbols for function padding") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Shuah Khan <skhan@linuxfoundation.org>
2023-02-21selftests/ftrace: Fix eprobe syntax test case to check filter supportMasami Hiramatsu (Google)1-1/+3
Fix eprobe syntax test case to check whether the kernel supports the filter on eprobe for filter syntax test command. Without this fix, this test case will fail if the kernel supports eprobe but doesn't support the filter on eprobe. Link: https://lore.kernel.org/all/167309834742.640500.379128668288448035.stgit@devnote3/ Fixes: 9e14bae7d049 ("selftests/ftrace: Add eprobe syntax error testcase") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Shuah Khan <skhan@linuxfoundation.org>
2023-02-13selftests/ftrace: Fix bash specific "==" operatorMasami Hiramatsu (Google)1-1/+1
Since commit a1d6cd88c897 ("selftests/ftrace: event_triggers: wait longer for test_event_enable") introduced bash specific "==" comparation operator, that test will fail when we run it on a posix-shell. `checkbashisms` warned it as below. possible bashism in ftrace/func_event_triggers.tc line 45 (should be 'b = a'): if [ "$e" == $val ]; then This replaces it with "=". Fixes: a1d6cd88c897 ("selftests/ftrace: event_triggers: wait longer for test_event_enable") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-01-25tracing/histogram: Add simple tests for stacktrace usage of synthetic eventsSteven Rostedt (Google)2-0/+30
Update the selftests to include a test of passing a stacktrace between the events of a synthetic event. Link: https://lkml.kernel.org/r/20230117152236.475439286@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Ross Zwisler <zwisler@google.com> Cc: Ching-lin Yu <chinglinyu@google.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-25tracing/selftests: Add test for event filtering on function nameSteven Rostedt (Google)1-0/+58
With the new filter logic of passing in the name of a function to match an instruction pointer (or the address of the function), add a test to make sure that it is functional. This is also the first test to test plain filtering. The filtering has been tested via the trigger logic, which uses the same code, but there was nothing to test just the event filter, so this test is the first to add such a case. Link: https://lkml.kernel.org/r/20221219183214.075559302@goodmis.org Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Zheng Yejian <zhengyejian1@huawei.com> Cc: linux-kselftest@vger.kernel.org Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Ross Zwisler <zwisler@google.com> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-12-21Merge tag 'trace-probes-v6.2' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull trace probes updates from Steven Rostedt: - New "symstr" type for dynamic events that writes the name of the function+offset into the ring buffer and not just the address - Prevent kernel symbol processing on addresses in user space probes (uprobes). - And minor fixes and clean ups * tag 'trace-probes-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Reject symbol/symstr type for uprobe tracing/probes: Add symstr type for dynamic events kprobes: kretprobe events missing on 2-core KVM guest kprobes: Fix check for probe enabled in kill_kprobe() test_kprobes: Fix implicit declaration error of test_kprobes tracing: Fix race where eprobes can be called before the event
2022-12-15tracing/probes: Reject symbol/symstr type for uprobeMasami Hiramatsu (Google)1-0/+5
Since uprobe's argument must contain the user-space data, that should not be converted to kernel symbols. Reject if user specifies these types on uprobe events. e.g. /sys/kernel/debug/tracing # echo 'p /bin/sh:10 %ax:symbol' >> uprobe_events sh: write error: Invalid argument /sys/kernel/debug/tracing # echo 'p /bin/sh:10 %ax:symstr' >> uprobe_events sh: write error: Invalid argument /sys/kernel/debug/tracing # cat error_log [ 1783.134883] trace_uprobe: error: Unknown type is specified Command: p /bin/sh:10 %ax:symbol ^ [ 1792.201120] trace_uprobe: error: Unknown type is specified Command: p /bin/sh:10 %ax:symstr ^ Link: https://lore.kernel.org/all/166679931679.1528100.15540755370726009882.stgit@devnote3/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-12-12Merge tag 'linux-kselftest-next-6.2-rc1' of ↵Linus Torvalds15-31/+34
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest updates from Shuah Khan: "Several fixes and enhancements to existing tests and a few new tests: - add new amd-pstate tests and fix and enhance existing ones - add new watchdog tests and enhance existing ones to improve coverage - fixes to ftrace, splice_read, rtc, and efivars tests - fixes to handle egrep obsolescence in the latest grep release - miscellaneous spelling and SPDX fixes" * tag 'linux-kselftest-next-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (24 commits) selftests/ftrace: Use long for synthetic event probe test selftests/tpm2: Split async tests call to separate shell script runner selftests: splice_read: Fix sysfs read cases selftests: ftrace: Use "grep -E" instead of "egrep" selftests: gpio: Use "grep -E" instead of "egrep" selftests: kselftest_deps: Use "grep -E" instead of "egrep" selftests/efivarfs: Add checking of the test return value cpufreq: amd-pstate: fix spdxcheck warnings for amd-pstate-ut.c selftests: rtc: skip when RTC is not present selftests/ftrace: event_triggers: wait longer for test_event_enable selftests/vDSO: Add riscv getcpu & gettimeofday test Documentation: amd-pstate: Add tbench and gitsource test introduction selftests: amd-pstate: Trigger gitsource benchmark and test cpus selftests: amd-pstate: Trigger tbench benchmark and test cpus selftests: amd-pstate: Split basic.sh into run.sh and basic.sh. selftests: amd-pstate: Rename amd-pstate-ut.sh to basic.sh. selftests/ftrace: Convert tracer tests to use 'requires' to specify program dependency selftests/ftrace: Add check for ping command for trigger tests selftests/watchdog: Fix spelling mistake "Temeprature" -> "Temperature" selftests/watchdog: add test for WDIOC_GETTEMP ...
2022-12-02selftests/ftrace: Use long for synthetic event probe testSteven Rostedt (Google)1-1/+1
On 32bit the trigger-synthetic-eprobe.tc selftest fails with the error: hist:syscalls:sys_exit_openat: error: Param type doesn't match synthetic event field type Command: hist:keys=common_pid:filename=$__arg__1,ret=ret:onmatch(syscalls.sys_enter_openat).trace(synth_open,$filename,$ret) ^ This is because the synth_open synthetic event is created with: echo "$SYNTH u64 filename; s64 ret;" > synthetic_events Which works fine on 64 bit, as filename is a pointer and the return is also a long. But for 32 bit architectures, it doesn't work. Use "unsigned long" and "long" instead so that it works for both 64 bit and 32 bit architectures. Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-11-25selftests: ftrace: Use "grep -E" instead of "egrep"Tiezhu Yang1-4/+4
The latest version of grep claims the egrep is now obsolete so the build now contains warnings that look like: egrep: warning: egrep is obsolescent; using grep -E fix this up by moving the related file to use "grep -E" instead. sed -i "s/egrep/grep -E/g" `grep egrep -rwl tools/testing/selftests/ftrace` Here are the steps to install the latest grep: wget http://ftp.gnu.org/gnu/grep/grep-3.8.tar.gz tar xf grep-3.8.tar.gz cd grep-3.8 && ./configure && make sudo make install export PATH=/usr/local/bin:$PATH Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-11-14selftests/ftrace: event_triggers: wait longer for test_event_enableYipeng Zou1-4/+11
In some platform, the schedule event may came slowly, delay 100ms can't cover it. I was notice that on my board which running in low cpu_freq,and this selftests allways gose fail. So maybe we can check more times here to wait longer. Fixes: 43bb45da82f9 ("selftests: ftrace: Add a selftest to test event enable/disable func trigger") Signed-off-by: Yipeng Zou <zouyipeng@huawei.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-28selftests/ftrace: Convert tracer tests to use 'requires' to specify program ↵Naveen N. Rao2-12/+2
dependency Now that we have a good way to specify dependency of tests on programs, convert some of the tracer tests to use this method for specifying dependency on 'chrt'. Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-28selftests/ftrace: Add check for ping command for trigger testsNaveen N. Rao10-10/+16
All these tests depend on the ping command and will fail if it is not found. Allow tests to specify dependencies on programs through the 'requires' field. Add dependency on 'ping' for some of the trigger tests. Link: https://lore.kernel.org/all/20221017104312.16af5467@gandalf.local.home/ Reported-by: Akanksha J N <akanksha@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-18selftests/ftrace: fix dynamic_events dependency checkSven Schnelle2-2/+2
commit 95c104c378dc ("tracing: Auto generate event name when creating a group of events") changed the syntax in the ftrace README file which is used by the selftests to check what features are support. Adjust the string to make test_duplicates.tc and trigger-synthetic-eprobe.tc work again. Fixes: 95c104c378dc ("tracing: Auto generate event name when creating a group of events") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-12Merge tag 'linux-kselftest-next-6.1-rc1-2' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull more Kselftest updates from Shuah Khan: "This consists of fixes and improvements to memory-hotplug test and a minor spelling fix to ftrace test" * tag 'linux-kselftest-next-6.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: docs: notifier-error-inject: Correct test's name selftests/memory-hotplug: Adjust log info for maintainability selftests/memory-hotplug: Restore memory before exit selftests/memory-hotplug: Add checking after online or offline selftests/ftrace: func_event_triggers: fix typo in user message
2022-10-07selftests/ftrace: func_event_triggers: fix typo in user messageRandy Dunlap1-1/+1
Correct typo of "it's" to "it". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: linux-kselftest@vger.kernel.org Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-26selftests/ftrace: Add eprobe syntax error testcaseMasami Hiramatsu (Google)1-0/+27
Add a syntax error test case for eprobe as same as kprobes. Link: https://lkml.kernel.org/r/165932115471.2850673.8014722990775242727.stgit@devnote2 Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-24selftests/kprobe: Update test for no event name syntax errorMasami Hiramatsu (Google)1-0/+1
The commit 208003254c32 ("selftests/kprobe: Do not test for GRP/ without event failures") removed a syntax which is no more cause a syntax error (NO_EVENT_NAME error with GRP/). However, there are another case (NO_EVENT_NAME error without GRP/) which causes a same error. This adds a test for that case. Link: https://lkml.kernel.org/r/165812790993.1377963.9762767354560397298.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-24selftests/kprobe: Do not test for GRP/ without event failuresSteven Rostedt (Google)1-1/+0
A new feature is added where kprobes (and other probes) do not need to explicitly state the event name when creating a probe. The event name will come from what is being attached. That is: # echo 'p:foo/ vfs_read' > kprobe_events Will no longer error, but instead create an event: # cat kprobe_events p:foo/p_vfs_read_0 vfs_read This should not be tested as an error case anymore. Remove it from the selftest as now this feature "breaks" the selftest as it no longer fails as expected. Link: https://lore.kernel.org/all/1656296348-16111-1-git-send-email-quic_linyyuan@quicinc.com/ Link: https://lkml.kernel.org/r/20220712161707.6dc08a14@gandalf.local.home Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-24selftests/ftrace: Add test case for GRP/ only inputLinyu Yuan2-1/+15
Add kprobe and eprobe event test for new GRP/ only format. Link: https://lore.kernel.org/all/1656296348-16111-5-git-send-email-quic_linyyuan@quicinc.com/ Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-30Merge tag 'mips_5.19' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux Pull MIPS updates from Thomas Bogendoerfer: "Cleanups and fixes" * tag 'mips_5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (38 commits) MIPS: RALINK: Define pci_remap_iospace under CONFIG_PCI_DRIVERS_GENERIC MIPS: Use memblock_add_node() in early_parse_mem() under CONFIG_NUMA MIPS: Return -EINVAL if mem parameter is empty in early_parse_mem() MIPS: Kconfig: Fix indentation and add endif comment MIPS: bmips: Fix compiler warning observed on W=1 build MIPS: Rewrite `csum_tcpudp_nofold' in plain C mips: setup: use strscpy to replace strlcpy MIPS: Octeon: add SNIC10E board MIPS: Ingenic: Refresh defconfig for CU1000-Neo and CU1830-Neo. MIPS: Ingenic: Refresh device tree for Ingenic SoCs and boards. MIPS: Ingenic: Add PWM nodes for X1830. MIPS: Octeon: fix typo in comment MIPS: loongson32: Kconfig: Remove extra space MIPS: Sibyte: remove unnecessary return variable MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation selftests/ftrace: Save kprobe_events to test log MIPS: tools: no need to initialise statics to 0 MIPS: Loongson: Use hwmon_device_register_with_groups() to register hwmon MIPS: VR41xx: Drop redundant spinlock initialization MIPS: smp: optimization for flush_tlb_mm when exiting ...
2022-05-12selftests/ftrace: Save kprobe_events to test logTiezhu Yang1-0/+2
It may lead to kernel panic when execute the following testcase on mips: # cd tools/testing/selftests/ftrace # ./ftracetest test.d/kprobe/multiple_kprobes.tc A preliminary analysis shows that the issue is related with echo 1 > events/kprobes/enable after add the 256 probe points. In order to find the root cause, I want to verify which probe point has problem, so it is necessary to save kprobe_events to test log. With this patch, we can get the 256 probe points in the test log through the following command: # ./ftracetest test.d/kprobe/multiple_kprobes.tc -vvv -k Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2022-04-19selftests/ftrace: add mips support for kprobe args syntax testsZe Zhang1-0/+4
This is the mips variant of commit <3990b5baf225> ("selftests/ftrace: Add s390 support for kprobe args tests"). Signed-off-by: Ze Zhang <zhangze@loongson.cn> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-04-19selftests/ftrace: add mips support for kprobe args string testsZe Zhang1-0/+3
This is the mips variant of commit <3990b5baf225> ("selftests/ftrace: Add s390 support for kprobe args tests"). Signed-off-by: Ze Zhang <zhangze@loongson.cn> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-02-14selftests/ftrace: Do not trace do_softirq because of PREEMPT_RTKrzysztof Kozlowski1-1/+1
The PREEMPT_RT patchset does not use do_softirq() function thus trying to filter for do_softirq fails for such kernel: echo do_softirq ftracetest: 81: echo: echo: I/O error Choose some other visible function for the test. The function does not have to be actually executed during the test, because it is only testing filter API interface. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-12-10selftests/ftrace: make kprobe profile testcase description uniqueHeiko Carstens1-1/+1
Commit 32f6e5da83c7 ("selftests/ftrace: Add kprobe profile testcase") added a new kprobes testcase, but has a description which does not describe what the test case is doing and is duplicating the description of another test case. Therefore change the test case description, so it is unique and then allows easily to tell which test case actually passed or failed. Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-11-06Merge tag 's390-5.16-1' of ↵Linus Torvalds2-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Add support for ftrace with direct call and ftrace direct call samples. - Add support for kernel command lines longer than current 896 bytes and make its length configurable. - Add support for BEAR enhancement facility to improve last breaking event instruction tracking. - Add kprobes sanity checks and testcases to prevent kprobe in the mid of an instruction. - Allow concurrent access to /dev/hwc for the CPUMF users. - Various ftrace / jump label improvements. - Convert unwinder tests to KUnit. - Add s390_iommu_aperture kernel parameter to tweak the limits on concurrently usable DMA mappings. - Add ap.useirq AP module option which can be used to disable interrupt use. - Add add_disk() error handling support to block device drivers. - Drop arch specific and use generic implementation of strlcpy and strrchr. - Several __pa/__va usages fixes. - Various cio, crypto, pci, kernel doc and other small fixes and improvements all over the code. [ Merge fixup as per https://lore.kernel.org/all/YXAqZ%2FEszRisunQw@osiris/ ] * tag 's390-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (63 commits) s390: make command line configurable s390: support command lines longer than 896 bytes s390/kexec_file: move kernel image size check s390/pci: add s390_iommu_aperture kernel parameter s390/spinlock: remove incorrect kernel doc indicator s390/string: use generic strlcpy s390/string: use generic strrchr s390/ap: function rework based on compiler warning s390/cio: make ccw_device_dma_* more robust s390/vfio-ap: s390/crypto: fix all kernel-doc warnings s390/hmcdrv: fix kernel doc comments s390/ap: new module option ap.useirq s390/cpumf: Allow multiple processes to access /dev/hwc s390/bitops: return true/false (not 1/0) from bool functions s390: add support for BEAR enhancement facility s390: introduce nospec_uses_trampoline() s390: rename last_break to pgm_last_break s390/ptrace: add last_break member to pt_regs s390/sclp: sort out physical vs virtual pointers usage s390/setup: convert start and end initrd pointers to virtual ...
2021-11-03Merge tag 'trace-v5.16-2' of ↵Linus Torvalds1-0/+63
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: - osnoise and timerlat updates that will work with the RTLA tool (Real-Time Linux Analysis). Specifically it disconnects the work load (threads that look for latency) from the tracing instances attached to them, allowing for more than one instance to retrieve data from the work load. - Optimization on division in the trace histogram trigger code to use shift and multiply when possible. Also added documentation. - Fix prototype to my_direct_func in direct ftrace trampoline sample code. * tag 'trace-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace/samples: Add missing prototype for my_direct_func tracing/selftests: Add tests for hist trigger expression parsing tracing/histogram: Document hist trigger variables tracing/histogram: Update division by 0 documentation tracing/histogram: Optimize division by constants tracing/osnoise: Remove PREEMPT_RT ifdefs from inside functions tracing/osnoise: Remove STACKTRACE ifdefs from inside functions tracing/osnoise: Allow multiple instances of the same tracer tracing/osnoise: Remove TIMERLAT ifdefs from inside functions tracing/osnoise: Support a list of trace_array *tr tracing/osnoise: Use start/stop_per_cpu_kthreads() on osnoise_cpus_write() tracing/osnoise: Split workload start from the tracer start tracing/osnoise: Improve comments about barrier need for NMI callbacks tracing/osnoise: Do not follow tracing_cpumask