aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--include/linux/ptrace.h33
-rw-r--r--include/linux/tracehook.h52
2 files changed, 85 insertions, 0 deletions
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index c6f5f9dd0ce..c74abfc4c7e 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 00000000000..bea0f3eeff5
--- /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> */