• Steven Rostedt (Red Hat)'s avatar
    tracing: Add snapshot trigger to function probes · 77fd5c15
    Steven Rostedt (Red Hat) authored
     echo 'schedule:snapshot:1' > /debug/tracing/set_ftrace_filter
    
    This will cause the scheduler to trigger a snapshot the next time
    it's called (you can use any function that's not called by NMI).
    
    Even though it triggers only once, you still need to remove it with:
    
     echo '!schedule:snapshot:0' > /debug/tracing/set_ftrace_filter
    
    The :1 can be left off for the first command:
    
     echo 'schedule:snapshot' > /debug/tracing/set_ftrace_filter
    
    But this will cause all calls to schedule to trigger a snapshot.
    This must be removed without the ':0'
    
     echo '!schedule:snapshot' > /debug/tracing/set_ftrace_filter
    
    As adding a "count" is a different operation (internally).
    Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    77fd5c15
trace.c 145 KB