1. 19 Feb, 2009 1 commit
    • Steven Rostedt's avatar
      tracing: disable tracing while testing ring buffer · 0c5119c1
      Steven Rostedt authored
      Impact: fix to prevent hard lockup on self tests
      
      If one of the tracers are broken and is constantly filling the ring
      buffer while the test of the ring buffer is running, it will hang
      the box. The reason is that the test is a consumer that will not
      stop till the ring buffer is empty. But if the tracer is broken and
      is constantly producing input to the buffer, this test will never
      end. The result is a lockup of the box.
      
      This happened when KALLSYMS was not defined and the dynamic ftrace
      test constantly filled the ring buffer, because the filter failed
      and all functions were being traced. Something was being called
      that constantly filled the buffer.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      0c5119c1
  2. 17 Feb, 2009 1 commit
    • Frederic Weisbecker's avatar
      tracing/function-graph-tracer: trace the idle tasks · 5b058bcd
      Frederic Weisbecker authored
      When the function graph tracer is activated, it iterates over the task_list
      to allocate a stack to store the return addresses.
      
      But the per cpu idle tasks are not iterated by using
      do_each_thread / while_each_thread.
      
      So we have to iterate on them manually.
      
      This fixes somes weirdness in the traces and many losses of traces.
      Examples on two cpus:
      
       0)   Xorg-4287    |   2.906 us    |              }
       0)   Xorg-4287    |   3.965 us    |            }
       0)   Xorg-4287    |   5.302 us    |          }
       ------------------------------------------
       0)   Xorg-4287    =>    <idle>-0
       ------------------------------------------
      
       0)    <idle>-0    |   2.861 us    |                        }
       0)    <idle>-0    |   0.526 us    |                        set_normalized_timespec();
       0)    <idle>-0    |   7.201 us    |                      }
       0)    <idle>-0    |   8.214 us    |                    }
       0)    <idle>-0    |               |                    clockevents_program_event() {
       0)    <idle>-0    |               |                      lapic_next_event() {
       0)    <idle>-0    |   0.510 us    |                        native_apic_mem_write();
       0)    <idle>-0    |   1.546 us    |                      }
       0)    <idle>-0    |   2.583 us    |                    }
       0)    <idle>-0    | + 12.435 us   |                  }
       0)    <idle>-0    | + 13.470 us   |                }
       0)    <idle>-0    |   0.608 us    |                _spin_unlock_irqrestore();
       0)    <idle>-0    | + 23.270 us   |              }
       0)    <idle>-0    | + 24.336 us   |            }
       0)    <idle>-0    | + 25.417 us   |          }
       0)    <idle>-0    |   0.593 us    |          _spin_unlock();
       0)    <idle>-0    | + 41.869 us   |        }
       0)    <idle>-0    | + 42.906 us   |      }
       0)    <idle>-0    | + 95.035 us   |    }
       0)    <idle>-0    |   0.540 us    |    menu_reflect();
       0)    <idle>-0    | ! 100.404 us  |  }
       0)    <idle>-0    |   0.564 us    |  mce_idle_callback();
       0)    <idle>-0    |               |  enter_idle() {
       0)    <idle>-0    |   0.526 us    |    mce_idle_callback();
       0)    <idle>-0    |   1.757 us    |  }
       0)    <idle>-0    |               |  cpuidle_idle_call() {
       0)    <idle>-0    |               |    menu_select() {
       0)    <idle>-0    |   0.525 us    |      pm_qos_requirement();
       0)    <idle>-0    |   0.518 us    |      tick_nohz_get_sleep_length();
       0)    <idle>-0    |   2.621 us    |    }
      [...]
       1)    <idle>-0    |   0.518 us    |              touch_softlockup_watchdog();
       1)    <idle>-0    | + 14.355 us   |            }
       1)    <idle>-0    | + 22.840 us   |          }
       1)    <idle>-0    | + 25.949 us   |        }
       1)    <idle>-0    |               |        handle_irq() {
       1)    <idle>-0    |   0.511 us    |          irq_to_desc();
       1)    <idle>-0    |               |          handle_edge_irq() {
       1)    <idle>-0    |   0.638 us    |            _spin_lock();
       1)    <idle>-0    |               |            ack_apic_edge() {
       1)    <idle>-0    |   0.510 us    |              irq_to_desc();
       1)    <idle>-0    |               |              move_native_irq() {
       1)    <idle>-0    |   0.510 us    |                irq_to_desc();
       1)    <idle>-0    |   1.532 us    |              }
       1)    <idle>-0    |   0.511 us    |              native_apic_mem_write();
       ------------------------------------------
       1)    <idle>-0    =>    cat-5073
       ------------------------------------------
      
       1)    cat-5073    |   3.731 us    |                    }
       1)    cat-5073    |               |                    run_local_timers() {
       1)    cat-5073    |   0.533 us    |                      hrtimer_run_queues();
       1)    cat-5073    |               |                      raise_softirq() {
       1)    cat-5073    |               |                        __raise_softirq_irqoff() {
       1)    cat-5073    |               |                          /* nr: 1 */
       1)    cat-5073    |   2.718 us    |                        }
       1)    cat-5073    |   3.814 us    |                      }
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      5b058bcd
  3. 15 Feb, 2009 3 commits
    • Pekka Paalanen's avatar
      doc: mmiotrace.txt, buffer size control change · f9aa28ad
      Pekka Paalanen authored
      Impact: prevents confusing the user when buffer size is inadequate
      
      The tracing framework offers a resizeable buffer, which mmiotrace uses
      to record events. If the buffer is full, the following events will be
      lost. Events should not be lost, so the documentation instructs the user
      to increase the buffer size. The buffer size is set via a debugfs file.
      
      Mmiotrace documentation was not updated the same time the debugfs file
      was changed. The old file was tracing/trace_entries and first contained
      the number of entries the buffer had space for, per cpu. Nowadays this
      file is replaced with the file tracing/buffer_size_kb, which tells the
      amount of memory reserved for the buffer, per cpu, in kilobytes.
      
      Previously, a flag had to be toggled via the debugfs file
      tracing/tracing_enabled when the buffer size was changed. This is no
      longer necessary.
      
      The mmiotrace documentation is updated to reflect the current state of
      the tracing framework.
      Signed-off-by: default avatarPekka Paalanen <pq@iki.fi>
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      f9aa28ad
    • Pekka Paalanen's avatar
      trace: mmiotrace to the tracer menu in Kconfig · 6bc5c366
      Pekka Paalanen authored
      Impact: cosmetic change in Kconfig menu layout
      
      This patch was originally suggested by Peter Zijlstra, but seems it
      was forgotten.
      
      CONFIG_MMIOTRACE and CONFIG_MMIOTRACE_TEST were selectable
      directly under the Kernel hacking / debugging menu in the kernel
      configuration system. They were present only for x86 and x86_64.
      
      Other tracers that use the ftrace tracing framework are in their own
      sub-menu. This patch moves the mmiotrace configuration options there.
      Since the Kconfig file, where the tracer menu is, is not architecture
      specific, HAVE_MMIOTRACE_SUPPORT is introduced and provided only by
      x86/x86_64. CONFIG_MMIOTRACE now depends on it.
      Signed-off-by: default avatarPekka Paalanen <pq@iki.fi>
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      6bc5c366
    • Pekka Paalanen's avatar
      mmiotrace: count events lost due to not recording · 391b170f
      Pekka Paalanen authored
      Impact: enhances lost events counting in mmiotrace
      
      The tracing framework, or the ring buffer facility it uses, has a switch
      to stop recording data. When recording is off, the trace events will be
      lost. The framework does not count these, so mmiotrace has to count them
      itself.
      Signed-off-by: default avatarPekka Paalanen <pq@iki.fi>
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      391b170f
  4. 13 Feb, 2009 33 commits
  5. 12 Feb, 2009 2 commits