1. 17 Mar, 2009 1 commit
  2. 13 Mar, 2009 4 commits
  3. 06 Mar, 2009 2 commits
  4. 20 Feb, 2009 3 commits
    • Steven Rostedt's avatar
      ftrace: break out modify loop immediately on detection of error · 4377245a
      Steven Rostedt authored
      
      
      Impact: added precaution on failure detection
      
      Break out of the modifying loop as soon as a failure is detected.
      This is just an added precaution found by code review and was not
      found by any bug chasing.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      4377245a
    • Steven Rostedt's avatar
      ftrace: allow archs to preform pre and post process for code modification · 000ab691
      Steven Rostedt authored
      
      
      This patch creates the weak functions: ftrace_arch_code_modify_prepare
      and ftrace_arch_code_modify_post_process that are called before and
      after the stop machine is called to modify the kernel text.
      
      If the arch needs to do pre or post processing, it only needs to define
      these functions.
      
      [ Update: Ingo Molnar suggested using the name ftrace_arch_code_modify_*
                over using ftrace_arch_modify_* ]
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      000ab691
    • Frederic Weisbecker's avatar
      tracing/function-graph-tracer: make set_graph_function file support ftrace regex · f9349a8f
      Frederic Weisbecker authored
      
      
      Impact: trace only functions matching a pattern
      
      The set_graph_function file let one to trace only one or several
      chosen functions and follow all their code flow.
      
      Currently, only a constant function name is allowed so this patch
      allows the ftrace_regex functions:
      
      - matches all functions that end with "name":
        echo *name > set_graph_function
      
      - matches all functions that begin with "name":
        echo name* > set_graph_function
      
      - matches all functions that contains "name":
        echo *name* > set_graph_function
      
      Example:
      
      echo mutex* > set_graph_function
      
       0)               |  mutex_lock_nested() {
       0)   0.563 us    |    __might_sleep();
       0)   2.072 us    |  }
       0)               |  mutex_unlock() {
       0)   1.036 us    |    __mutex_unlock_slowpath();
       0)   2.433 us    |  }
       0)               |  mutex_unlock() {
       0)   0.691 us    |    __mutex_unlock_slowpath();
       0)   1.787 us    |  }
       0)               |  mutex_lock_interruptible_nested() {
       0)   0.548 us    |    __might_sleep();
       0)   1.945 us    |  }
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      f9349a8f
  5. 17 Feb, 2009 7 commits
    • 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
    • Steven Rostedt's avatar
      ftrace: rename _hook to _probe · b6887d79
      Steven Rostedt authored
      
      
      Impact: clean up
      
      Ingo Molnar did not like the _hook naming convention used by the
      select function tracer. Luis Claudio R. Goncalves suggested using
      the "_probe" extension. This patch implements the change of
      calling the functions and variables "_hook" and replacing them
      with "_probe".
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      b6887d79
    • Steven Rostedt's avatar
      ftrace: clean up coding style · 6a24a244
      Steven Rostedt authored
      
      
      Ingo Molnar pointed out some coding style issues with the recent ftrace
      updates. This patch cleans them up.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      6a24a244
    • Ingo Molnar's avatar
      ftrace: fix !CONFIG_DYNAMIC_FTRACE ftrace_swapper_pid definition · 73d3fd96
      Ingo Molnar authored
      
      
      Impact: build fix
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      73d3fd96
    • Steven Rostedt's avatar
      ftrace: add pretty print to selected fuction traces · 809dcf29
      Steven Rostedt authored
      
      
      This patch adds a call back for the tracers that have hooks to
      selected functions. This allows the tracer to show better output
      in the set_ftrace_filter file.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      809dcf29
    • Steven Rostedt's avatar
      ftrace: show selected functions in set_ftrace_filter · 8fc0c701
      Steven Rostedt authored
      
      
      This patch adds output to show what functions have tracer hooks
      attached to them.
      
        # echo 'sys_open:traceon:4' > /debug/tracing/set_ftrace_filter
        # cat set_ftrace_filter
      
       #### all functions enabled ####
       sys_open:ftrace_traceon:0000000000000004
      
        # echo 'do_fork:traceoff:' > set_ftrace_filter
        # cat set_ftrace_filter
      
       #### all functions enabled ####
       sys_open:ftrace_traceon:0000000000000002
       do_fork:ftrace_traceoff:ffffffffffffffff
      
      Note the 4 changed to a 2. This is because The code was executed twice
      since the traceoff was added. If a cat is done again:
      
       #### all functions enabled ####
       sys_open:ftrace_traceon
       do_fork:ftrace_traceoff:ffffffffffffffff
      
      The number disappears. That is because it will not print a NULL.
      
      Callbacks to allow the tracer to pretty print will be implemented soon.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      8fc0c701
    • Steven Rostedt's avatar
      ftrace: trace different functions with a different tracer · 59df055f
      Steven Rostedt authored
      
      
      Impact: new feature
      
      Currently, the function tracer only gives you an ability to hook
      a tracer to all functions being traced. The dynamic function trace
      allows you to pick and choose which of those functions will be
      traced, but all functions being traced will call all tracers that
      registered with the function tracer.
      
      This patch adds a new feature that allows a tracer to hook to specific
      functions, even when all functions are being traced. It allows for
      different functions to call different tracer hooks.
      
      The way this is accomplished is by a special function that will hook
      to the function tracer and will set up a hash table knowing which
      tracer hook to call with which function. This is the most general
      and easiest method to accomplish this. Later, an arch may choose
      to supply their own method in changing the mcount call of a function
      to call a different tracer. But that will be an exercise for the
      future.
      
      To register a function:
      
       struct ftrace_hook_ops {
      	void			(*func)(unsigned long ip,
      					unsigned long parent_ip,
      					void **data);
      	int			(*callback)(unsigned long ip, void **data);
      	void			(*free)(void **data);
       };
      
       int register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
      				  void *data);
      
      glob is a simple glob to search for the functions to hook.
      ops is a pointer to the operations (listed below)
      data is the default data to be passed to the hook functions when traced
      
      ops:
       func is the hook function to call when the functions are traced
       callback is a callback function that is called when setting up the hash.
         That is, if the tracer needs to do something special for each
         function, that is being traced, and wants to give each function
         its own data. The address of the entry data is passed to this
         callback, so that the callback may wish to update the entry to
         whatever it would like.
       free is a callback for when the entry is freed. In case the tracer
         allocated any data, it is give the chance to free it.
      
      To unregister we have three functions:
      
        void
        unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
      				void *data)
      
      This will unregister all hooks that match glob, point to ops, and
      have its data matching data. (note, if glob is NULL, blank or '*',
      all functions will be tested).
      
        void
        unregister_ftrace_function_hook_func(char *glob,
      				 struct ftrace_hook_ops *ops)
      
      This will unregister all functions matching glob that has an entry
      pointing to ops.
      
        void unregister_ftrace_function_hook_all(char *glob)
      
      This simply unregisters all funcs.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      59df055f
  6. 16 Feb, 2009 9 commits
    • Steven Rostedt's avatar
      ftrace: consolidate mutexes · e6ea44e9
      Steven Rostedt authored
      
      
      Impact: clean up
      
      Now that ftrace_lock is a mutex, there is no reason to have three
      different mutexes protecting similar data. All the mutex paths
      are not in hot paths, so having a mutex to cover more data is
      not a problem.
      
      This patch removes the ftrace_sysctl_lock and ftrace_start_lock
      and uses the ftrace_lock to protect the locations that were protected
      by these locks. By doing so, this change also removes some of
      the lock nesting that was taking place.
      
      There are still more mutexes in ftrace.c that can probably be
      consolidated, but they can be dealt with later. We need to be careful
      about the way the locks are nested, and by consolidating, we can cause
      a recursive deadlock.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      e6ea44e9
    • Steven Rostedt's avatar
      ftrace: convert ftrace_lock from a spinlock to mutex · 52baf119
      Steven Rostedt authored
      
      
      Impact: clean up
      
      The older versions of ftrace required doing the ftrace list
      search under atomic context. Now all the calls are in non-atomic
      context. There is no reason to keep the ftrace_lock as a spinlock.
      
      This patch converts it to a mutex.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      52baf119
    • Steven Rostedt's avatar
      ftrace: add command interface for function selection · f6180773
      Steven Rostedt authored
      
      
      Allow for other tracers to add their own commands for function
      selection. This interface gives a trace the ability to name a
      command for function selection. Right now it is pretty limited
      in what it offers, but this is a building step for more features.
      
      The :mod: command is converted to this interface and also serves
      as a template for other implementations.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      f6180773
    • Steven Rostedt's avatar
      ftrace: enable filtering only when a function is filtered on · e68746a2
      Steven Rostedt authored
      
      
      Impact: fix to prevent empty set_ftrace_filter and no ftrace output
      
      The function filter is used to only trace a given set of functions.
      The filter is enabled when a function name is echoed into the
      set_ftrace_filter file. But if the name has a typo and the function
      is not found, the filter is enabled, but no function is listed.
      
      This makes a confusing situation where set_ftrace_filter is empty
      but no functions ever get enabled for tracing.
      
      For example:
      
       # cat /debug/tracing/set_ftrace_filter
      
        #### all functions enabled ####
      
       # echo bad_name > set_ftrace_filter
       # cat /debug/tracing/set_ftrace_filter
      
       # echo function > current_tracer
       # cat trace
      
        # tracer: nop
        #
        #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
        #              | |       |          |         |
      
      This patch changes that to only enable filtering if a function
      is set to be filtered on. Now, the filter is not enabled if
      a bad name is echoed into set_ftrace_filter.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      e68746a2
    • Steven Rostedt's avatar
      ftrace: add module command function filter selection · 64e7c440
      Steven Rostedt authored
      
      
      This patch adds a "command" syntax to the function filtering files:
      
        /debugfs/tracing/set_ftrace_filter
        /debugfs/tracing/set_ftrace_notrace
      
      Of the format:  <function>:<command>:<parameter>
      
      The command is optional, and dependent on the command, so are
      the parameters.
      
       echo do_fork > set_ftrace_filter
      
      Will only trace 'do_fork'.
      
       echo 'sched_*' > set_ftrace_filter
      
      Will only trace functions starting with the letters 'sched_'.
      
       echo '*:mod:ext3' > set_ftrace_filter
      
      Will trace only the ext3 module functions.
      
       echo '*write*:mod:ext3' > set_ftrace_notrace
      
      Will prevent the ext3 functions with the letters 'write' in
      the name from being traced.
      
       echo '!*_allocate:mod:ext3' > set_ftrace_filter
      
      Will remove the functions in ext3 that end with the letters
      '_allocate' from the ftrace filter.
      
      Although this patch implements the 'command' format, only the
      'mod' command is supported. More commands to follow.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      64e7c440
    • Steven Rostedt's avatar
      ftrace: break up ftrace_match_records into smaller components · 9f4801e3
      Steven Rostedt authored
      
      
      Impact: clean up
      
      ftrace_match_records does a lot of things that other features
      can use. This patch breaks up ftrace_match_records and pulls
      out ftrace_setup_glob and ftrace_match_record.
      
      ftrace_setup_glob prepares a simple glob expression for use with
      ftrace_match_record. ftrace_match_record compares a single record
      with a glob type.
      
      Breaking this up will allow for more features to run on individual
      records.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      9f4801e3
    • Steven Rostedt's avatar
      ftrace: rename ftrace_match to ftrace_match_records · 7f24b31b
      Steven Rostedt authored
      
      
      Impact: clean up
      
      ftrace_match is too generic of a name. What it really does is
      search all records and matches the records with the given string,
      and either sets or unsets the functions to be traced depending
      on if the parameter 'enable' is set or not.
      
      This allows us to make another function called ftrace_match that
      can be used to test a single record.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      7f24b31b
    • Steven Rostedt's avatar
      ftrace: add do_for_each_ftrace_rec and while_for_each_ftrace_rec · 265c831c
      Steven Rostedt authored
      
      
      Impact: clean up
      
      To iterate over all the functions that dynamic trace knows about
      it requires two for loops. One to iterate over the pages and the
      other to iterate over the records within the page.
      
      There are several duplications of these loops in ftrace.c. This
      patch creates the macros do_for_each_ftrace_rec and
      while_for_each_ftrace_rec to handle this logic, and removes the
      duplicate code.
      
      While making this change, I also discovered and fixed a small
      bug that one of the iterations should exit the loop after it found the
      record it was searching for. This used a break when it should have
      used a goto, since there were two loops it needed to break out
      from.  No real harm was done by this bug since it would only continue
      to search the other records, and the code was in a slow path anyway.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      265c831c
    • Steven Rostedt's avatar
      ftrace: state that all functions are enabled in set_ftrace_filter · 0c75a3ed
      Steven Rostedt authored
      
      
      Impact: clean up, make set_ftrace_filter less confusing
      
      The set_ftrace_filter shows only the functions that will be traced.
      But when it is empty, it will trace all functions. This can be a bit
      confusing.
      
      This patch makes set_ftrace_filter show:
      
        #### all functions enabled ####
      
      When all functions will be traced, and we do not filter only a select
      few.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      0c75a3ed
  7. 08 Feb, 2009 1 commit
  8. 03 Feb, 2009 1 commit
  9. 21 Jan, 2009 1 commit
    • Frederic Weisbecker's avatar
      tracing/function-graph-tracer: fix a regression while suspend to disk · 00f57f54
      Frederic Weisbecker authored
      
      
      Impact: fix a crash while kernel image restore
      
      When the function graph tracer is running and while suspend to disk, some racy
      and dangerous things happen against this tracer.
      
      The current task will save its registers including the stack pointer which
      contains the return address hooked by the tracer. But the current task will
      continue to enter other functions after that to save the memory, and then
      it will store other return addresses, and finally loose the old depth which
      matches the return address saved in the old stack (during the registers saving).
      
      So on image restore, the code will return to wrong addresses.
      And there are other things: on restore, the task will have it's "current"
      pointer overwritten during registers restoring....switching from one task to
      another... That would be insane to try to trace function graphs at these
      stages.
      
      This patch makes the function graph tracer listening on power events, making
      it's tracing disabled for the current task (the one that performs the
      hibernation work) while suspend/resume to disk, making the tracing safe
      during hibernation.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      00f57f54
  10. 15 Jan, 2009 1 commit
    • Frederic Weisbecker's avatar
      tracing/function-graph-tracer: fix a regression while suspend to disk · 4a2b8dda
      Frederic Weisbecker authored
      
      
      Impact: fix a crash while kernel image restore
      
      When the function graph tracer is running and while suspend to disk, some racy
      and dangerous things happen against this tracer.
      
      The current task will save its registers including the stack pointer which
      contains the return address hooked by the tracer. But the current task will
      continue to enter other functions after that to save the memory, and then
      it will store other return addresses, and finally loose the old depth which
      matches the return address saved in the old stack (during the registers saving).
      
      So on image restore, the code will return to wrong addresses.
      And there are other things: on restore, the task will have it's "current"
      pointer overwritten during registers restoring....switching from one task to
      another... That would be insane to try to trace function graphs at these
      stages.
      
      This patch makes the function graph tracer listening on power events, making
      it's tracing disabled for the current task (the one that performs the
      hibernation work) while suspend/resume to disk, making the tracing safe
      during hibernation.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      4a2b8dda
  11. 14 Jan, 2009 3 commits
  12. 07 Jan, 2009 1 commit
  13. 18 Dec, 2008 1 commit
    • 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
  14. 08 Dec, 2008 1 commit
  15. 05 Dec, 2008 1 commit
    • Steven Rostedt's avatar
      ftrace: use init_struct_pid as swapper pid · 21bbecda
      Steven Rostedt authored
      
      
      Impact: clean up
      
      Using (struct pid *)-1 as the pointer for ftrace_swapper_pid is
      a little confusing for others. This patch uses the address of the
      actual init pid structure instead. This change is only for
      clarity. It does not affect the code itself. Hopefully soon the
      swapper tasks will all have their own pid structure and then
      we can clean up the code a bit more.
      Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      21bbecda
  16. 04 Dec, 2008 3 commits