• Steven Rostedt's avatar
    ftrace: add not to regex on filtering functions · ea3a6d6d
    Steven Rostedt authored
    Impact: enhancement
    
    Ingo Molnar has asked about a way to remove items from the filter
    lists. Currently, you can only add or replace items. The way
    items are added to the list is through opening one of the list
    files (set_ftrace_filter or set_ftrace_notrace) via append.
    If the file is opened for truncate, the list is cleared.
    
      echo spin_lock > /debug/tracing/set_ftrace_filter
    
    The above will replace the list with only spin_lock
    
      echo spin_lock >> /debug/tracing/set_ftrace_filter
    
    The above will add spin_lock to the list.
    
    Now this patch adds:
    
      echo '!spin_lock' >> /debug/tracing/set_ftrace_filter
    
    This will remove spin_lock from the list.
    
    The limited glob features of these lists also can be notted.
    
      echo '!spin_*' >> /debug/tracing/set_ftrace_filter
    
    This will remove all functions that start with 'spin_'
    
    Note:
    
      echo '!spin_*' > /debug/tracing/set_ftrace_filter
    
    will simply clear out the list (notice the '>' instead of '>>')
    Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
    Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    ea3a6d6d
ftrace.c 43.2 KB