These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / Documentation / trace / ftrace.txt

diff --git a/kernel/Documentation/trace/ftrace.txt b/kernel/Documentation/trace/ftrace.txt
index 572ca92..f52f297 100644 (file)
--- a/kernel/Documentation/trace/ftrace.txt
+++ b/kernel/Documentation/trace/ftrace.txt
@@ -108,8 +108,8 @@ of ftrace. Here is a list of some of the key files:
        data is read from this file, it is consumed, and
        will not be read again with a sequential read. The
        "trace" file is static, and if the tracer is not
-       adding more data,they will display the same
-       information every time they are read.
+       adding more data, it will display the same
+       information every time it is read.
 
   trace_options:
 
@@ -204,6 +204,12 @@ of ftrace. Here is a list of some of the key files:
 
        Have the function tracer only trace a single thread.
 
+  set_event_pid:
+
+       Have the events only trace a task with a PID listed in this file.
+       Note, sched_switch and sched_wake_up will also trace events
+       listed in this file.
+
   set_graph_function:
 
        Set a "trigger" function where tracing should start
@@ -346,6 +352,11 @@ of ftrace. Here is a list of some of the key files:
          x86-tsc: Architectures may define their own clocks. For
                   example, x86 uses its own TSC cycle clock here.
 
+         ppc-tb: This uses the powerpc timebase register value.
+                 This is in sync across CPUs and can also be used
+                 to correlate events across hypervisor/guest if
+                 tb_offset is known.
+
        To set a clock, simply echo the clock name into this file.
 
          echo global > trace_clock
@@ -686,6 +697,8 @@ The above is mostly meaningful for kernel developers.
         The marks are determined by the difference between this
         current trace and the next trace.
          '$' - greater than 1 second
+         '@' - greater than 100 milisecond
+         '*' - greater than 10 milisecond
          '#' - greater than 1000 microsecond
          '!' - greater than 100 microsecond
          '+' - greater than 10 microsecond
@@ -1939,26 +1952,49 @@ want, depending on your needs.
 
   ie:
 
-  0)               |    up_write() {
-  0)   0.646 us    |      _spin_lock_irqsave();
-  0)   0.684 us    |      _spin_unlock_irqrestore();
-  0)   3.123 us    |    }
-  0)   0.548 us    |    fput();
-  0) + 58.628 us   |  }
+  3) # 1837.709 us |          } /* __switch_to */
+  3)               |          finish_task_switch() {
+  3)   0.313 us    |            _raw_spin_unlock_irq();
+  3)   3.177 us    |          }
+  3) # 1889.063 us |        } /* __schedule */
+  3) ! 140.417 us  |      } /* __schedule */
+  3) # 2034.948 us |    } /* schedule */
+  3) * 33998.59 us |  } /* schedule_preempt_disabled */
 
   [...]
 
-  0)               |      putname() {
-  0)               |        kmem_cache_free() {
-  0)   0.518 us    |          __phys_addr();
-  0)   1.757 us    |        }
-  0)   2.861 us    |      }
-  0) ! 115.305 us  |    }
-  0) ! 116.402 us  |  }
+  1)   0.260 us    |              msecs_to_jiffies();
+  1)   0.313 us    |              __rcu_read_unlock();
+  1) + 61.770 us   |            }
+  1) + 64.479 us   |          }
+  1)   0.313 us    |          rcu_bh_qs();
+  1)   0.313 us    |          __local_bh_enable();
+  1) ! 217.240 us  |        }
+  1)   0.365 us    |        idle_cpu();
+  1)               |        rcu_irq_exit() {
+  1)   0.417 us    |          rcu_eqs_enter_common.isra.47();
+  1)   3.125 us    |        }
+  1) ! 227.812 us  |      }
+  1) ! 457.395 us  |    }
+  1) @ 119760.2 us |  }
+
+  [...]
+
+  2)               |    handle_IPI() {
+  1)   6.979 us    |                  }
+  2)   0.417 us    |      scheduler_ipi();
+  1)   9.791 us    |                }
+  1) + 12.917 us   |              }
+  2)   3.490 us    |    }
+  1) + 15.729 us   |            }
+  1) + 18.542 us   |          }
+  2) $ 3594274 us  |  }
 
   + means that the function exceeded 10 usecs.
   ! means that the function exceeded 100 usecs.
   # means that the function exceeded 1000 usecs.
+  * means that the function exceeded 10 msecs.
+  @ means that the function exceeded 100 msecs.
   $ means that the function exceeded 1 sec.
 
 
@@ -2407,6 +2443,23 @@ The following commands are supported:
 
    echo '!writeback*:mod:ext3' >> set_ftrace_filter
 
+  Mod command supports module globbing. Disable tracing for all
+  functions except a specific module:
+
+   echo '!*:mod:!ext3' >> set_ftrace_filter
+
+  Disable tracing for all modules, but still trace kernel:
+
+   echo '!*:mod:*' >> set_ftrace_filter
+
+  Enable filter only for kernel:
+
+   echo '*write*:mod:!*' >> set_ftrace_filter
+
+  Enable filter for module globbing:
+
+   echo '*write*:mod:*snd*' >> set_ftrace_filter
+
 - traceon/traceoff
   These commands turn tracing on and off when the specified
   functions are hit. The parameter determines how many times the