• Linus Torvalds's avatar
    Merge tag 'trace-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace · cccf0c2e
    Linus Torvalds authored
    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"
    cccf0c2e
ftrace.c 196 KB