• Linus Torvalds's avatar
    Merge tag 'trace-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace · e919a3f7
    Linus Torvalds authored
    Pull more tracing updates from Steven Rostedt:
    
     - Make buffer_percent read/write.
    
       The buffer_percent file is how users can state how long to block on
       the tracing buffer depending on how much is in the buffer. When it
       hits the "buffer_percent" it will wake the task waiting on the
       buffer. For some reason it was set to read-only.
    
       This was not noticed because testing was done as root without
       SELinux, but with SELinux it will prevent even root to write to it
       without having CAP_DAC_OVERRIDE.
    
     - The "touched_functions" was added this merge window, but one of the
       reasons for adding it was not implemented.
    
       That was to show what functions were not only touched, but had either
       a direct trampoline attached to it, or a kprobe or live kernel
       patching that can "hijack" the function to run a different function.
       The point is to know if there's functions in the kernel that may not
       be behaving as the kernel code shows. This can be used for debugging.
    
       TODO: Add this information to kernel oops too.
    
    * tag 'trace-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
      ftrace: Add MODIFIED flag to show if IPMODIFY or direct was attached
      tracing: Fix permissions for the buffer_percent file
    e919a3f7
ftrace.h 38.6 KB