target/linux/orion/patches/001-latencytop_support.patch

   1 From: Nicolas Pitre <nico@cam.org>
   2
   3 Signed-off-by: Nicolas Pitre <nico@marvell.com>
   4 Tested-by: Lennert Buytenhek <buytenh@marvell.com>
   5 Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
   6 ---
   7  arch/arm/Kconfig             |    4 ++++
   8  arch/arm/kernel/stacktrace.c |   26 ++++++++++++++++++++++----
   9  2 files changed, 26 insertions(+), 4 deletions(-)
  10
  11 --- a/arch/arm/Kconfig
  12 +++ b/arch/arm/Kconfig
  13 @@ -84,6 +84,10 @@
  14         bool
  15         default y
  16
  17 +config HAVE_LATENCYTOP_SUPPORT
  18 +       bool
  19 +       default y
  20 +
  21  config LOCKDEP_SUPPORT
  22         bool
  23         default y
  24 --- a/arch/arm/kernel/stacktrace.c
  25 +++ b/arch/arm/kernel/stacktrace.c
  26 @@ -36,6 +36,7 @@
  27  #ifdef CONFIG_STACKTRACE
  28  struct stack_trace_data {
  29         struct stack_trace *trace;
  30 +       unsigned int no_sched_functions;
  31         unsigned int skip;
  32  };
  33
  34 @@ -43,27 +44,44 @@
  35  {
  36         struct stack_trace_data *data = d;
  37         struct stack_trace *trace = data->trace;
  38 +       unsigned long addr = frame->lr;
  39
  40 +       if (data->no_sched_functions && in_sched_functions(addr))
  41 +               return 0;
  42         if (data->skip) {
  43                 data->skip--;
  44                 return 0;
  45         }
  46
  47 -       trace->entries[trace->nr_entries++] = frame->lr;
  48 +       trace->entries[trace->nr_entries++] = addr;
  49
  50         return trace->nr_entries >= trace->max_entries;
  51  }
  52
  53 -void save_stack_trace(struct stack_trace *trace)
  54 +void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
  55  {
  56         struct stack_trace_data data;
  57         unsigned long fp, base;
  58
  59         data.trace = trace;
  60         data.skip = trace->skip;
  61 -       base = (unsigned long)task_stack_page(current);
  62 -       asm("mov %0, fp" : "=r" (fp));
  63 +       base = (unsigned long)task_stack_page(tsk);
  64 +
  65 +       if (tsk != current) {
  66 +               data.no_sched_functions = 1;
  67 +               fp = thread_saved_fp(tsk);
  68 +       } else {
  69 +               data.no_sched_functions = 0;
  70 +               asm("mov %0, fp" : "=r" (fp));
  71 +       }
  72
  73         walk_stackframe(fp, base, base + THREAD_SIZE, save_trace, &data);
  74 +       if (trace->nr_entries < trace->max_entries)
  75 +               trace->entries[trace->nr_entries++] = ULONG_MAX;
  76 +}
  77 +
  78 +void save_stack_trace(struct stack_trace *trace)
  79 +{
  80 +       save_stack_trace_tsk(current, trace);
  81  }
  82  #endif