The utrace User Debugging Infrastructure

Table of Contents

1. utrace concepts

Introduction

Events and Callbacks

Stopping Safely

Writing well-behaved callbacks

Using UTRACE_STOP

Tear-down Races

Primacy of SIGKILL

Final callbacks

Engine and task pointers

Serialization of DEATH and REAP

Interlock with final callbacks

Using utrace_barrier

2. utrace core API

enum utrace_resume_action — engine's choice of action for a traced task

utrace_resume_action — enum utrace_resume_action from callback action

enum utrace_signal_action — disposition of signal

utrace_signal_action — enum utrace_signal_action from callback action

enum utrace_syscall_action — disposition of system call attempt

utrace_syscall_action — enum utrace_syscall_action from callback action

struct utrace_engine — per-engine structure

utrace_engine_get — acquire a reference on a struct utrace_engine

utrace_engine_put — release a reference on a struct utrace_engine

struct utrace_engine_ops — tracing engine callbacks

struct utrace_examiner — private state for using utrace_prepare_examine

utrace_control_pid — control a thread being traced by a tracing engine

utrace_set_events_pid — choose which event reports a tracing engine gets

utrace_barrier_pid — synchronize with simultaneous tracing callbacks

utrace_attach_task — attach new engine, or look up an attached engine

utrace_attach_pid — attach new engine, or look up an attached engine

utrace_set_events — choose which event reports a tracing engine gets

utrace_control — control a thread being traced by a tracing engine

utrace_barrier — synchronize with simultaneous tracing callbacks

utrace_prepare_examine — prepare to examine thread state

utrace_finish_examine — complete an examination of thread state

3. Machine State

struct user_regset

System Call Information

System Call Tracing

4. Kernel Internals

Core Calls In

Architecture Calls Out

<asm/ptrace.h>

<asm/syscall.h>

<linux/tracehook.h>