x86: disable BTS ptrace extensions for now

revert the BTS ptrace extension for now.

based on general objections from Roland McGrath:

    http://lkml.org/lkml/2008/2/21/323

we'll let the BTS functionality cook some more and re-enable
it in v2.6.26. We'll leave the dead code around to help the
development of this code.

(X86_BTS is not defined at the moment)

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 43f287744f9f..3baf9b9f4c87 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -604,11 +604,13 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
                 memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
         }
 
+#ifdef X86_BTS
         if (test_tsk_thread_flag(prev_p, TIF_BTS_TRACE_TS))
                 ptrace_bts_take_timestamp(prev_p, BTS_TASK_DEPARTS);
 
         if (test_tsk_thread_flag(next_p, TIF_BTS_TRACE_TS))
                 ptrace_bts_take_timestamp(next_p, BTS_TASK_ARRIVES);
+#endif
 }
 
 /*