Commit b4ef95de authored by Ingo Molnar's avatar Ingo Molnar
Browse files

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: default avatarIngo Molnar <mingo@elte.hu>
parent 8be8f54b

arch/x86/kernel/process_32.c

+2 −0
Original line number Diff line number Diff line
@@ -603,11 +603,13 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, 
	}

#endif



#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





	if (!test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {

arch/x86/kernel/process_64.c

+2 −0
Original line number Diff line number Diff line
@@ -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

}



/*

arch/x86/kernel/ptrace.c

+12 −0
Original line number Diff line number Diff line
@@ -544,6 +544,8 @@ static int ptrace_set_debugreg(struct task_struct *child, 
	return 0;

}



#ifdef X86_BTS



static int ptrace_bts_get_size(struct task_struct *child)

{

	if (!child->thread.ds_area_msr)
@@ -826,6 +828,7 @@ void ptrace_bts_take_timestamp(struct task_struct *tsk, 


	ptrace_bts_write_record(tsk, &rec);

}

#endif /* X86_BTS */



/*

 * Called by kernel/ptrace.c when detaching..
@@ -839,7 +842,9 @@ void ptrace_disable(struct task_struct *child) 
	clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);

#endif

	if (child->thread.ds_area_msr) {

#ifdef X86_BTS

		ptrace_bts_realloc(child, 0, 0);

#endif

		child->thread.debugctlmsr &= ~ds_debugctl_mask();

		if (!child->thread.debugctlmsr)

			clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
@@ -961,6 +966,10 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) 
		break;

#endif



	/*

	 * These bits need more cooking - not enabled yet:

	 */

#ifdef X86_BTS

	case PTRACE_BTS_CONFIG:

		ret = ptrace_bts_config

			(child, data, (struct ptrace_bts_config __user *)addr);
@@ -988,6 +997,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) 
		ret = ptrace_bts_drain

			(child, data, (struct bts_struct __user *) addr);

		break;

#endif



	default:

		ret = ptrace_request(child, request, addr, data);
@@ -1226,12 +1236,14 @@ asmlinkage long sys32_ptrace(long request, u32 pid, u32 addr, u32 data) 
	case PTRACE_SETOPTIONS:

	case PTRACE_SET_THREAD_AREA:

	case PTRACE_GET_THREAD_AREA:

#ifdef X86_BTS

	case PTRACE_BTS_CONFIG:

	case PTRACE_BTS_STATUS:

	case PTRACE_BTS_SIZE:

	case PTRACE_BTS_GET:

	case PTRACE_BTS_CLEAR:

	case PTRACE_BTS_DRAIN:

#endif

		return sys_ptrace(request, pid, addr, data);



	default:

CRA Git | Maintained and supported by SUSTech CRA and CCSE