diff options
| -rw-r--r-- | include/linux/ptrace.h | 33 | ||||
| -rw-r--r-- | include/linux/tracehook.h | 52 |
2 files changed, 85 insertions, 0 deletions
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index c6f5f9dd0cee..c74abfc4c7e8 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -121,6 +121,39 @@ static inline void ptrace_unlink(struct task_struct *child) int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data); int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data); +/** + * task_ptrace - return %PT_* flags that apply to a task + * @task: pointer to &task_struct in question + * + * Returns the %PT_* flags that apply to @task. + */ +static inline int task_ptrace(struct task_struct *task) +{ + return task->ptrace; +} + +/** + * ptrace_event - possibly stop for a ptrace event notification + * @mask: %PT_* bit to check in @current->ptrace + * @event: %PTRACE_EVENT_* value to report if @mask is set + * @message: value for %PTRACE_GETEVENTMSG to return + * + * This checks the @mask bit to see if ptrace wants stops for this event. + * If so we stop, reporting @event and @message to the ptrace parent. + * + * Returns nonzero if we did a ptrace notification, zero if not. + * + * Called without locks. + */ +static inline int ptrace_event(int mask, int event, unsigned long message) +{ + if (mask && likely(!(current->ptrace & mask))) + return 0; + current->ptrace_message = message; + ptrace_notify((event << 8) | SIGTRAP); + return 1; +} + #ifndef force_successful_syscall_return /* * System call handlers that, upon successful completion, need to return a diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h new file mode 100644 index 000000000000..bea0f3eeff54 --- /dev/null +++ b/include/linux/tracehook.h @@ -0,0 +1,52 @@ +/* + * Tracing hooks + * + * Copyright (C) 2008 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License v.2. + * + * This file defines hook entry points called by core code where + * user tracing/debugging support might need to do something. These + * entry points are called tracehook_*(). Each hook declared below + * has a detailed kerneldoc comment giving the context (locking et + * al) from which it is called, and the meaning of its return value. + * + * Each function here typically has only one call site, so it is ok + * to have some nontrivial tracehook_*() inlines. In all cases, the + * fast path when no tracing is enabled should be very short. + * + * The purpose of this file and the tracehook_* layer is to consolidate + * the interface that the kernel core and arch code uses to enable any + * user debugging or tracing facility (such as ptrace). The interfaces + * here are carefully documented so that maintainers of core and arch + * code do not need to think about the implementation details of the + * tracing facilities. Likewise, maintainers of the tracing code do not + * need to understand all the calling core or arch code in detail, just + * documented circumstances of each call, such as locking conditions. + * + * If the calling core code changes so that locking is different, then + * it is ok to change the interface documented here. The maintainer of + * core code changing should notify the maintainers of the tracing code + * that they need to work out the change. + * + * Some tracehook_*() inlines take arguments that the current tracing + * implementations might not necessarily use. These function signatures + * are chosen to pass in all the information that is on hand in the + * caller and might conceivably be relevant to a tracer, so that the + * core code won't have to be updated when tracing adds more features. + * If a call site changes so that some of those parameters are no longer + * already on hand without extra work, then the tracehook_* interface + * can change so there is no make-work burden on the core code. The + * maintainer of core code changing should notify the maintainers of the + * tracing code that they need to work out the change. + */ + +#ifndef _LINUX_TRACEHOOK_H +#define _LINUX_TRACEHOOK_H 1 + +#include <linux/sched.h> +#include <linux/ptrace.h> + +#endif /* <linux/tracehook.h> */ |