x86, ptrace: overflow signal API

Establish the user API for sending a user-defined signal to the traced task on a BTS buffer overflow.

This should complete the user API for the BTS ptrace extension.
The patches so far implement wrap-around overflow handling as is needed for debugging.

The remaining open is another overflow handling mechanism that sends a signal to the traced task on a buffer overflow.
This will take some more time from my side.

Since, from a user perspective, this occurs behind the scenes, the patch set should already be useful. More features may/will be added on top of it (overflow signal, pageable back-up buffers, kernel tracing, core file support, profiling, ...).

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Markus Metzger 2008-01-30 13:32:04 +01:00 committed by Ingo Molnar
parent cba4b65d35
commit c6334593c6

View file

@ -88,11 +88,13 @@ struct ptrace_bts_config {
unsigned int size;
/* bitmask of below flags */
unsigned int flags;
/* buffer overflow signal */
unsigned int signal;
};
#define PTRACE_BTS_O_TRACE 0x1 /* branch trace */
#define PTRACE_BTS_O_SCHED 0x2 /* scheduling events w/ jiffies */
#define PTRACE_BTS_O_SIGNAL 0x4 /* send SIG? on buffer overflow
#define PTRACE_BTS_O_SIGNAL 0x4 /* send SIG<signal> on buffer overflow
instead of wrapping around */
#define PTRACE_BTS_O_CUT_SIZE 0x8 /* cut requested size to max available
instead of failing */