|
|
@@ -71,12 +71,28 @@ typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
|
|
|
* could be controled by following calls:
|
|
|
* ftrace_function_local_enable
|
|
|
* ftrace_function_local_disable
|
|
|
+ * SAVE_REGS - The ftrace_ops wants regs saved at each function called
|
|
|
+ * and passed to the callback. If this flag is set, but the
|
|
|
+ * architecture does not support passing regs
|
|
|
+ * (ARCH_SUPPORTS_FTRACE_SAVE_REGS is not defined), then the
|
|
|
+ * ftrace_ops will fail to register, unless the next flag
|
|
|
+ * is set.
|
|
|
+ * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
|
|
|
+ * handler can handle an arch that does not save regs
|
|
|
+ * (the handler tests if regs == NULL), then it can set
|
|
|
+ * this flag instead. It will not fail registering the ftrace_ops
|
|
|
+ * but, the regs field will be NULL if the arch does not support
|
|
|
+ * passing regs to the handler.
|
|
|
+ * Note, if this flag is set, the SAVE_REGS flag will automatically
|
|
|
+ * get set upon registering the ftrace_ops, if the arch supports it.
|
|
|
*/
|
|
|
enum {
|
|
|
- FTRACE_OPS_FL_ENABLED = 1 << 0,
|
|
|
- FTRACE_OPS_FL_GLOBAL = 1 << 1,
|
|
|
- FTRACE_OPS_FL_DYNAMIC = 1 << 2,
|
|
|
- FTRACE_OPS_FL_CONTROL = 1 << 3,
|
|
|
+ FTRACE_OPS_FL_ENABLED = 1 << 0,
|
|
|
+ FTRACE_OPS_FL_GLOBAL = 1 << 1,
|
|
|
+ FTRACE_OPS_FL_DYNAMIC = 1 << 2,
|
|
|
+ FTRACE_OPS_FL_CONTROL = 1 << 3,
|
|
|
+ FTRACE_OPS_FL_SAVE_REGS = 1 << 4,
|
|
|
+ FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 5,
|
|
|
};
|
|
|
|
|
|
struct ftrace_ops {
|
|
|
@@ -254,12 +270,31 @@ extern void unregister_ftrace_function_probe_all(char *glob);
|
|
|
|
|
|
extern int ftrace_text_reserved(void *start, void *end);
|
|
|
|
|
|
+/*
|
|
|
+ * The dyn_ftrace record's flags field is split into two parts.
|
|
|
+ * the first part which is '0-FTRACE_REF_MAX' is a counter of
|
|
|
+ * the number of callbacks that have registered the function that
|
|
|
+ * the dyn_ftrace descriptor represents.
|
|
|
+ *
|
|
|
+ * The second part is a mask:
|
|
|
+ * ENABLED - the function is being traced
|
|
|
+ * REGS - the record wants the function to save regs
|
|
|
+ * REGS_EN - the function is set up to save regs.
|
|
|
+ *
|
|
|
+ * When a new ftrace_ops is registered and wants a function to save
|
|
|
+ * pt_regs, the rec->flag REGS is set. When the function has been
|
|
|
+ * set up to save regs, the REG_EN flag is set. Once a function
|
|
|
+ * starts saving regs it will do so until all ftrace_ops are removed
|
|
|
+ * from tracing that function.
|
|
|
+ */
|
|
|
enum {
|
|
|
- FTRACE_FL_ENABLED = (1 << 30),
|
|
|
+ FTRACE_FL_ENABLED = (1UL << 29),
|
|
|
+ FTRACE_FL_REGS = (1UL << 30),
|
|
|
+ FTRACE_FL_REGS_EN = (1UL << 31)
|
|
|
};
|
|
|
|
|
|
-#define FTRACE_FL_MASK (0x3UL << 30)
|
|
|
-#define FTRACE_REF_MAX ((1 << 30) - 1)
|
|
|
+#define FTRACE_FL_MASK (0x7UL << 29)
|
|
|
+#define FTRACE_REF_MAX ((1UL << 29) - 1)
|
|
|
|
|
|
struct dyn_ftrace {
|
|
|
union {
|
|
|
@@ -290,9 +325,23 @@ enum {
|
|
|
FTRACE_STOP_FUNC_RET = (1 << 4),
|
|
|
};
|
|
|
|
|
|
+/*
|
|
|
+ * The FTRACE_UPDATE_* enum is used to pass information back
|
|
|
+ * from the ftrace_update_record() and ftrace_test_record()
|
|
|
+ * functions. These are called by the code update routines
|
|
|
+ * to find out what is to be done for a given function.
|
|
|
+ *
|
|
|
+ * IGNORE - The function is already what we want it to be
|
|
|
+ * MAKE_CALL - Start tracing the function
|
|
|
+ * MODIFY_CALL - Stop saving regs for the function
|
|
|
+ * MODIFY_CALL_REGS - Start saving regs for the function
|
|
|
+ * MAKE_NOP - Stop tracing the function
|
|
|
+ */
|
|
|
enum {
|
|
|
FTRACE_UPDATE_IGNORE,
|
|
|
FTRACE_UPDATE_MAKE_CALL,
|
|
|
+ FTRACE_UPDATE_MODIFY_CALL,
|
|
|
+ FTRACE_UPDATE_MODIFY_CALL_REGS,
|
|
|
FTRACE_UPDATE_MAKE_NOP,
|
|
|
};
|
|
|
|
|
|
@@ -344,7 +393,9 @@ extern int ftrace_dyn_arch_init(void *data);
|
|
|
extern void ftrace_replace_code(int enable);
|
|
|
extern int ftrace_update_ftrace_func(ftrace_func_t func);
|
|
|
extern void ftrace_caller(void);
|
|
|
+extern void ftrace_regs_caller(void);
|
|
|
extern void ftrace_call(void);
|
|
|
+extern void ftrace_regs_call(void);
|
|
|
extern void mcount_call(void);
|
|
|
|
|
|
void ftrace_modify_all_code(int command);
|
|
|
@@ -352,6 +403,15 @@ void ftrace_modify_all_code(int command);
|
|
|
#ifndef FTRACE_ADDR
|
|
|
#define FTRACE_ADDR ((unsigned long)ftrace_caller)
|
|
|
#endif
|
|
|
+
|
|
|
+#ifndef FTRACE_REGS_ADDR
|
|
|
+#ifdef ARCH_SUPPORTS_FTRACE_SAVE_REGS
|
|
|
+# define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
|
|
|
+#else
|
|
|
+# define FTRACE_REGS_ADDR FTRACE_ADDR
|
|
|
+#endif
|
|
|
+#endif
|
|
|
+
|
|
|
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
|
extern void ftrace_graph_caller(void);
|
|
|
extern int ftrace_enable_ftrace_graph_caller(void);
|
|
|
@@ -407,6 +467,39 @@ extern int ftrace_make_nop(struct module *mod,
|
|
|
*/
|
|
|
extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
|
|
|
|
|
|
+#ifdef ARCH_SUPPORTS_FTRACE_SAVE_REGS
|
|
|
+/**
|
|
|
+ * ftrace_modify_call - convert from one addr to another (no nop)
|
|
|
+ * @rec: the mcount call site record
|
|
|
+ * @old_addr: the address expected to be currently called to
|
|
|
+ * @addr: the address to change to
|
|
|
+ *
|
|
|
+ * This is a very sensitive operation and great care needs
|
|
|
+ * to be taken by the arch. The operation should carefully
|
|
|
+ * read the location, check to see if what is read is indeed
|
|
|
+ * what we expect it to be, and then on success of the compare,
|
|
|
+ * it should write to the location.
|
|
|
+ *
|
|
|
+ * The code segment at @rec->ip should be a caller to @old_addr
|
|
|
+ *
|
|
|
+ * Return must be:
|
|
|
+ * 0 on success
|
|
|
+ * -EFAULT on error reading the location
|
|
|
+ * -EINVAL on a failed compare of the contents
|
|
|
+ * -EPERM on error writing to the location
|
|
|
+ * Any other value will be considered a failure.
|
|
|
+ */
|
|
|
+extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
|
|
|
+ unsigned long addr);
|
|
|
+#else
|
|
|
+/* Should never be called */
|
|
|
+static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
|
|
|
+ unsigned long addr)
|
|
|
+{
|
|
|
+ return -EINVAL;
|
|
|
+}
|
|
|
+#endif
|
|
|
+
|
|
|
/* May be defined in arch */
|
|
|
extern int ftrace_arch_read_dyn_info(char *buf, int size);
|
|
|
|
Steven Rostedt