lkml.org 
[lkml]   [2010]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 39/40] debug_core: Turn off tracing while in the debugger
FromSteven Rostedt <>
DateThu, 14 Jan 2010 19:10:10 -0500
On Thu, 2010-01-14 at 08:59 -0600, Jason Wessel wrote:
> The kernel debugger should turn off kernel tracing any time the
> debugger is active and restore it on resume.
>
> CC: Steven Rostedt <rostedt@goodmis.org>
> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
> ---
> kernel/debug/debug_core.c | 8 ++++++++
> 1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
> index 6ca3f7c..464aa65 100644
> --- a/kernel/debug/debug_core.c
> +++ b/kernel/debug/debug_core.c
> @@ -474,6 +474,7 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
> int sstep_tries = 100;
> int error;
> int i, cpu;
> + int trace_on = 0;
> acquirelock:
> /*
> * Interrupts will be restored by the 'trap return' code, except when
> @@ -518,6 +519,8 @@ return_normal:
> */
> if (arch_kgdb_ops.correct_hw_break)
> arch_kgdb_ops.correct_hw_break();
> + if (trace_on)
> + tracing_on();
> atomic_set(&cpu_in_kgdb[cpu], 0);
> touch_softlockup_watchdog_sync();
> clocksource_touch_watchdog();
> @@ -592,6 +595,9 @@ return_normal:
> kgdb_single_step = 0;
> kgdb_contthread = current;
> exception_level = 0;
> + trace_on = tracing_is_on();
> + if (trace_on)
> + tracing_off();

Hmm, what happens if tracing gets turned on by something else? Will it
break this code? If so, we may need to do something different here.

-- Steve

>
> while (1) {
> cpu_master_loop:
> @@ -642,6 +648,8 @@ kgdb_restore:
> else
> kgdb_sstep_pid = 0;
> }
> + if (trace_on)
> + tracing_on();
> /* Free kgdb_active */
> atomic_set(&kgdb_active, -1);
> touch_softlockup_watchdog_sync();




\
 
 \ /
  Last update: 2010-01-15 01:13    [from the cache]
©2003-2010