struct module;
struct ftrace_hash;
+struct ftrace_direct_func;
#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_MODULES) && \
defined(CONFIG_DYNAMIC_FTRACE)
* PID - Is affected by set_ftrace_pid (allows filtering on those pids)
* RCU - Set when the ops can only be called when RCU is watching.
* TRACE_ARRAY - The ops->private points to a trace_array descriptor.
+ * PERMANENT - Set when the ops is permanent and should not be affected by
+ * ftrace_enabled.
+ * DIRECT - Used by the direct ftrace_ops helper for direct functions
+ * (internal ftrace only, should not be used by others)
*/
enum {
- FTRACE_OPS_FL_ENABLED = 1 << 0,
- FTRACE_OPS_FL_DYNAMIC = 1 << 1,
- FTRACE_OPS_FL_SAVE_REGS = 1 << 2,
- FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 3,
- FTRACE_OPS_FL_RECURSION_SAFE = 1 << 4,
- FTRACE_OPS_FL_STUB = 1 << 5,
- FTRACE_OPS_FL_INITIALIZED = 1 << 6,
- FTRACE_OPS_FL_DELETED = 1 << 7,
- FTRACE_OPS_FL_ADDING = 1 << 8,
- FTRACE_OPS_FL_REMOVING = 1 << 9,
- FTRACE_OPS_FL_MODIFYING = 1 << 10,
- FTRACE_OPS_FL_ALLOC_TRAMP = 1 << 11,
- FTRACE_OPS_FL_IPMODIFY = 1 << 12,
- FTRACE_OPS_FL_PID = 1 << 13,
- FTRACE_OPS_FL_RCU = 1 << 14,
- FTRACE_OPS_FL_TRACE_ARRAY = 1 << 15,
+ FTRACE_OPS_FL_ENABLED = BIT(0),
+ FTRACE_OPS_FL_DYNAMIC = BIT(1),
+ FTRACE_OPS_FL_SAVE_REGS = BIT(2),
+ FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = BIT(3),
+ FTRACE_OPS_FL_RECURSION_SAFE = BIT(4),
+ FTRACE_OPS_FL_STUB = BIT(5),
+ FTRACE_OPS_FL_INITIALIZED = BIT(6),
+ FTRACE_OPS_FL_DELETED = BIT(7),
+ FTRACE_OPS_FL_ADDING = BIT(8),
+ FTRACE_OPS_FL_REMOVING = BIT(9),
+ FTRACE_OPS_FL_MODIFYING = BIT(10),
+ FTRACE_OPS_FL_ALLOC_TRAMP = BIT(11),
+ FTRACE_OPS_FL_IPMODIFY = BIT(12),
+ FTRACE_OPS_FL_PID = BIT(13),
+ FTRACE_OPS_FL_RCU = BIT(14),
+ FTRACE_OPS_FL_TRACE_ARRAY = BIT(15),
+ FTRACE_OPS_FL_PERMANENT = BIT(16),
+ FTRACE_OPS_FL_DIRECT = BIT(17),
};
#ifdef CONFIG_DYNAMIC_FTRACE
static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { }
#endif /* CONFIG_FUNCTION_TRACER */
+struct ftrace_func_entry {
+ struct hlist_node hlist;
+ unsigned long ip;
+ unsigned long direct; /* for direct lookup only */
+};
+
+struct dyn_ftrace;
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+extern int ftrace_direct_func_count;
+int register_ftrace_direct(unsigned long ip, unsigned long addr);
+int unregister_ftrace_direct(unsigned long ip, unsigned long addr);
+int modify_ftrace_direct(unsigned long ip, unsigned long old_addr, unsigned long new_addr);
+struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr);
+int ftrace_modify_direct_caller(struct ftrace_func_entry *entry,
+ struct dyn_ftrace *rec,
+ unsigned long old_addr,
+ unsigned long new_addr);
+#else
+# define ftrace_direct_func_count 0
+static inline int register_ftrace_direct(unsigned long ip, unsigned long addr)
+{
+ return -ENOTSUPP;
+}
+static inline int unregister_ftrace_direct(unsigned long ip, unsigned long addr)
+{
+ return -ENOTSUPP;
+}
+static inline int modify_ftrace_direct(unsigned long ip,
+ unsigned long old_addr, unsigned long new_addr)
+{
+ return -ENOTSUPP;
+}
+static inline struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr)
+{
+ return NULL;
+}
+static inline int ftrace_modify_direct_caller(struct ftrace_func_entry *entry,
+ struct dyn_ftrace *rec,
+ unsigned long old_addr,
+ unsigned long new_addr)
+{
+ return -ENODEV;
+}
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
+
+#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+/*
+ * This must be implemented by the architecture.
+ * It is the way the ftrace direct_ops helper, when called
+ * via ftrace (because there's other callbacks besides the
+ * direct call), can inform the architecture's trampoline that this
+ * routine has a direct caller, and what the caller is.
+ *
+ * For example, in x86, it returns the direct caller
+ * callback function via the regs->orig_ax parameter.
+ * Then in the ftrace trampoline, if this is set, it makes
+ * the return from the trampoline jump to the direct caller
+ * instead of going back to the function it just traced.
+ */
+static inline void arch_ftrace_set_direct_caller(struct pt_regs *regs,
+ unsigned long addr) { }
+#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
+
#ifdef CONFIG_STACK_TRACER
extern int stack_tracer_enabled;
int ftrace_arch_code_modify_prepare(void);
int ftrace_arch_code_modify_post_process(void);
-struct dyn_ftrace;
-
enum ftrace_bug_type {
FTRACE_BUG_UNKNOWN,
FTRACE_BUG_INIT,
* REGS_EN - the function is set up to save regs.
* IPMODIFY - the record allows for the IP address to be changed.
* DISABLED - the record is not ready to be touched yet
+ * DIRECT - there is a direct function to call
*
* 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
FTRACE_FL_TRAMP_EN = (1UL << 27),
FTRACE_FL_IPMODIFY = (1UL << 26),
FTRACE_FL_DISABLED = (1UL << 25),
+ FTRACE_FL_DIRECT = (1UL << 24),
+ FTRACE_FL_DIRECT_EN = (1UL << 23),
};
-#define FTRACE_REF_MAX_SHIFT 25
-#define FTRACE_FL_BITS 7
+#define FTRACE_REF_MAX_SHIFT 23
+#define FTRACE_FL_BITS 9
#define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
#define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
#define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
/**
* ftrace_make_nop - convert code into nop
* @mod: module structure if called by module load initialization
- * @rec: the mcount call site record
+ * @rec: the call site record (e.g. mcount/fentry)
* @addr: the address that the call site should be calling
*
* This is a very sensitive operation and great care needs
extern int ftrace_make_nop(struct module *mod,
struct dyn_ftrace *rec, unsigned long addr);
+
+/**
+ * ftrace_init_nop - initialize a nop call site
+ * @mod: module structure if called by module load initialization
+ * @rec: the call site record (e.g. mcount/fentry)
+ *
+ * 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 contain the contents created by
+ * the compiler
+ *
+ * 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.
+ */
+#ifndef ftrace_init_nop
+static inline int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec)
+{
+ return ftrace_make_nop(mod, rec, MCOUNT_ADDR);
+}
+#endif
+
/**
* ftrace_make_call - convert a nop call site into a call to addr
- * @rec: the mcount call site record
+ * @rec: the call site record (e.g. mcount/fentry)
* @addr: the address that the call site should call
*
* This is a very sensitive operation and great care needs
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
/**
* ftrace_modify_call - convert from one addr to another (no nop)
- * @rec: the mcount call site record
+ * @rec: the call site record (e.g. mcount/fentry)
* @old_addr: the address expected to be currently called to
* @addr: the address to change to
*
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
extern void ftrace_init(void);
+#ifdef CC_USING_PATCHABLE_FUNCTION_ENTRY
+#define FTRACE_CALLSITE_SECTION "__patchable_function_entries"
+#else
+#define FTRACE_CALLSITE_SECTION "__mcount_loc"
+#endif
#else
static inline void ftrace_init(void) { }
#endif
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