mirror of
https://github.com/torvalds/linux.git
synced 2024-12-25 12:21:37 +00:00
97f7943d70
The following is a patch provided by Ananth Mavinakayanahalli that implements
the new PPC64 specific parts of the new function return probe design.
NOTE: Since getting Ananth's patch, I changed trampoline_probe_handler()
to consume each of the outstanding return probem instances (feedback
on my original RFC after Ananth cut a patch), and also added the
arch_init() function (adding arch specific initialization.) I have
cross compiled but have not testing this on a PPC64 machine.
Changes include:
* Addition of kretprobe_trampoline to act as a dummy function for instrumented
functions to return to, and for the return probe infrastructure to place
a kprobe on on, gaining control so that the return probe handler
can be called, and so that the instruction pointer can be moved back
to the original return address.
* Addition of arch_init(), allowing a kprobe to be registered on
kretprobe_trampoline
* Addition of trampoline_probe_handler() which is used as the pre_handler
for the kprobe inserted on kretprobe_implementation. This is the function
that handles the details for calling the return probe handler function
and returning control back at the original return address
* Addition of arch_prepare_kretprobe() which is setup as the pre_handler
for a kprobe registered at the beginning of the target function by
kernel/kprobes.c so that a return probe instance can be setup when
a caller enters the target function. (A return probe instance contains
all the needed information for trampoline_probe_handler to do it's job.)
* Hooks added to the exit path of a task so that we can cleanup any left-over
return probe instances (i.e. if a task dies while inside a targeted function
then the return probe instance was reserved at the beginning of the function
but the function never returns so we need to mark the instance as unused.)
Signed-off-by: Rusty Lynch <rusty.lynch@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
65 lines
2.1 KiB
C
65 lines
2.1 KiB
C
#ifndef _ASM_KPROBES_H
|
|
#define _ASM_KPROBES_H
|
|
/*
|
|
* Kernel Probes (KProbes)
|
|
* include/asm-ppc64/kprobes.h
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
*
|
|
* Copyright (C) IBM Corporation, 2002, 2004
|
|
*
|
|
* 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
|
|
* Probes initial implementation ( includes suggestions from
|
|
* Rusty Russell).
|
|
* 2004-Nov Modified for PPC64 by Ananth N Mavinakayanahalli
|
|
* <ananth@in.ibm.com>
|
|
*/
|
|
#include <linux/types.h>
|
|
#include <linux/ptrace.h>
|
|
|
|
struct pt_regs;
|
|
|
|
typedef unsigned int kprobe_opcode_t;
|
|
#define BREAKPOINT_INSTRUCTION 0x7fe00008 /* trap */
|
|
#define MAX_INSN_SIZE 1
|
|
|
|
#define IS_TW(instr) (((instr) & 0xfc0007fe) == 0x7c000008)
|
|
#define IS_TD(instr) (((instr) & 0xfc0007fe) == 0x7c000088)
|
|
#define IS_TDI(instr) (((instr) & 0xfc000000) == 0x08000000)
|
|
#define IS_TWI(instr) (((instr) & 0xfc000000) == 0x0c000000)
|
|
|
|
#define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)((func_descr_t *)pentry)
|
|
|
|
#define ARCH_SUPPORTS_KRETPROBES
|
|
void kretprobe_trampoline(void);
|
|
|
|
/* Architecture specific copy of original instruction */
|
|
struct arch_specific_insn {
|
|
/* copy of original instruction */
|
|
kprobe_opcode_t *insn;
|
|
};
|
|
|
|
#ifdef CONFIG_KPROBES
|
|
extern int kprobe_exceptions_notify(struct notifier_block *self,
|
|
unsigned long val, void *data);
|
|
#else /* !CONFIG_KPROBES */
|
|
static inline int kprobe_exceptions_notify(struct notifier_block *self,
|
|
unsigned long val, void *data)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
#endif /* _ASM_KPROBES_H */
|