1. 18 Nov, 2008 5 commits
    • Frederic Weisbecker's avatar
      tracing/function-return-tracer: add the overrun field · 0231022c
      Frederic Weisbecker authored
      
      
      Impact: help to find the better depth of trace
      
      We decided to arbitrary define the depth of function return trace as
      "20". Perhaps this is not enough. To help finding an optimal depth, we
      measure now the overrun: the number of functions that have been missed
      for the current thread. By default this is not displayed, we have to
      do set a particular flag on the return tracer: echo overrun >
      /debug/tracing/trace_options And the overrun will be printed on the
      right.
      
      As the trace shows below, the current 20 depth is not enough.
      
      update_wall_time+0x37f/0x8c0 -> update_xtime_cache (345 ns) (Overruns: 2838)
      update_wall_time+0x384/0x8c0 -> clocksource_get_next (1141 ns) (Overruns: 2838)
      do_timer+0x23/0x100 -> update_wall_time (3882 ns) (Overruns: 2838)
      tick_do_update_jiffies64+0xbf/0x160 -> do_timer (5339 ns) (Overruns: 2838)
      tick_sched_timer+0x6a/0xf0 -> tick_do_update_jiffies64 (7209 ns) (Overruns: 2838)
      vgacon_set_cursor_size+0x98/0x120 -> native_io_delay (2613 ns) (Overruns: 274)
      vgacon_cursor+0x16e/0x1d0 -> vgacon_set_cursor_size (33151 ns) (Overruns: 274)
      set_cursor+0x5f/0x80 -> vgacon_cursor (36432 ns) (Overruns: 274)
      con_flush_chars+0x34/0x40 -> set_cursor (38790 ns) (Overruns: 274)
      release_console_sem+0x1ec/0x230 -> up (721 ns) (Overruns: 274)
      release_console_sem+0x225/0x230 -> wake_up_klogd (316 ns) (Overruns: 274)
      con_flush_chars+0x39/0x40 -> release_console_sem (2996 ns) (Overruns: 274)
      con_write+0x22/0x30 -> con_flush_chars (46067 ns) (Overruns: 274)
      n_tty_write+0x1cc/0x360 -> con_write (292670 ns) (Overruns: 274)
      smp_apic_timer_interrupt+0x2a/0x90 -> native_apic_mem_write (330 ns) (Overruns: 274)
      irq_enter+0x17/0x70 -> idle_cpu (413 ns) (Overruns: 274)
      smp_apic_timer_interrupt+0x2f/0x90 -> irq_enter (1525 ns) (Overruns: 274)
      ktime_get_ts+0x40/0x70 -> getnstimeofday (465 ns) (Overruns: 274)
      ktime_get_ts+0x60/0x70 -> set_normalized_timespec (436 ns) (Overruns: 274)
      ktime_get+0x16/0x30 -> ktime_get_ts (2501 ns) (Overruns: 274)
      hrtimer_interrupt+0x77/0x1a0 -> ktime_get (3439 ns) (Overruns: 274)
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      0231022c
    • Frederic Weisbecker's avatar
      tracing/ftrace: make nop tracer using tracer flags · 0619faf6
      Frederic Weisbecker authored
      
      
      Impact: give an example on how to use specific tracer flags
      
      This patch propose to use the nop tracer to provide an
      example for using the tracer's custom flags implementation.
      
      V2: replace structures and defines just after the headers includes for
          cleanliness.
      V3: replace defines by enum values.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Acked-by: default avatarSteven Noonan <steven@uplinklabs.net>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      0619faf6
    • Frederic Weisbecker's avatar
      tracing/ftrace: implement a set_flag callback for tracers · adf9f195
      Frederic Weisbecker authored
      
      
      Impact: give a way to send specific messages to tracers
      
      The current implementation of tracing uses some flags to control the
      output of general tracers. But we have no way to implement custom
      flags handling for a specific tracer. This patch proposes a new
      callback for the struct tracer which called set_flag and a structure
      that represents a 32 bits variable flag.
      
      A tracer can implement a struct tracer_flags on which it puts the
      initial value of the flag integer. Than it can place a range of flags
      with their name and their flag mask on the flag integer. The structure
      that implement a single flag is called struct tracer_opt.
      
      These custom flags will be available through the trace_options file
      like the general tracing flags. Changing their value is done like the
      other general flags. For example if you have a flag that calls "foo",
      you can activate it by writing "foo" or "nofoo" on trace_options.
      
      Note that the set_flag callback is optional and is only needed if you
      want the flags changing to be signaled to your tracer and let it to
      accept or refuse their assignment.
      
      V2: Some arrangements in coding style....
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      adf9f195
    • Ingo Molnar's avatar
    • Rakib Mullick's avatar
      kernel/profile.c: fix section mismatch warning · e270219f
      Rakib Mullick authored
      
      
      Impact: fix section mismatch warning in kernel/profile.c
      
      Here, profile_nop function has been called from a non-init function
      create_hash_tables(void). Which generetes a section mismatch warning.
      Previously, create_hash_tables(void) was a init function. So, removing
      __init from create_hash_tables(void) requires profile_nop to be
      non-init.
      
      This patch makes profile_nop function inline and fixes the
      following warning:
      
       WARNING: vmlinux.o(.text+0x6ebb6): Section mismatch in reference from
       the function create_hash_tables() to the function
       .init.text:profile_nop()
       The function create_hash_tables() references
       the function __init profile_nop().
       This is often because create_hash_tables lacks a __init
       annotation or the annotation of profile_nop is wrong.
      Signed-off-by: default avatarRakib Mullick <rakib.mullick@gmail.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      e270219f
  2. 17 Nov, 2008 2 commits
  3. 16 Nov, 2008 33 commits