@@ -44,6 +44,25 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
regs_set_return_ip(&fregs->regs, ip);
}
+static __always_inline unsigned long
+ftrace_regs_get_instruction_pointer(struct ftrace_regs *fregs)
+{
+ return instruction_pointer(&fregs->regs);
+}
+
+#define ftrace_regs_get_argument(fregs, n) \
+ regs_get_kernel_argument(&(fregs)->regs, n)
+#define ftrace_regs_get_stack_pointer(fregs) \
+ kernel_stack_pointer(&(fregs)->regs)
+#define ftrace_regs_return_value(fregs) \
+ regs_return_value(&(fregs)->regs)
+#define ftrace_regs_set_return_value(fregs, ret) \
+ regs_set_return_value(&(fregs)->regs, ret)
+#define ftrace_override_function_with_return(fregs) \
+ override_function_with_return(&(fregs)->regs)
+#define ftrace_regs_query_register_offset(name) \
+ regs_query_register_offset(name)
+
struct ftrace_ops;
#define ftrace_graph_func ftrace_graph_func
@@ -54,6 +54,12 @@ static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *
return NULL;
}
+static __always_inline unsigned long
+ftrace_regs_get_instruction_pointer(const struct ftrace_regs *fregs)
+{
+ return fregs->regs.psw.addr;
+}
+
static __always_inline void
ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
unsigned long ip)
@@ -61,6 +67,19 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
fregs->regs.psw.addr = ip;
}
+#define ftrace_regs_get_argument(fregs, n) \
+ regs_get_kernel_argument(&(fregs)->regs, n)
+#define ftrace_regs_get_stack_pointer(fregs) \
+ kernel_stack_pointer(&(fregs)->regs)
+#define ftrace_regs_return_value(fregs) \
+ regs_return_value(&(fregs)->regs)
+#define ftrace_regs_set_return_value(fregs, ret) \
+ regs_set_return_value(&(fregs)->regs, ret)
+#define ftrace_override_function_with_return(fregs) \
+ override_function_with_return(&(fregs)->regs)
+#define ftrace_regs_query_register_offset(name) \
+ regs_query_register_offset(name)
+
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
/*
* When an ftrace registered caller is tracing a function that is
@@ -51,6 +51,22 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs)
#define ftrace_regs_set_instruction_pointer(fregs, _ip) \
do { (fregs)->regs.ip = (_ip); } while (0)
+#define ftrace_regs_get_instruction_pointer(fregs) \
+ ((fregs)->regs.ip)
+
+#define ftrace_regs_get_argument(fregs, n) \
+ regs_get_kernel_argument(&(fregs)->regs, n)
+#define ftrace_regs_get_stack_pointer(fregs) \
+ kernel_stack_pointer(&(fregs)->regs)
+#define ftrace_regs_return_value(fregs) \
+ regs_return_value(&(fregs)->regs)
+#define ftrace_regs_set_return_value(fregs, ret) \
+ regs_set_return_value(&(fregs)->regs, ret)
+#define ftrace_override_function_with_return(fregs) \
+ override_function_with_return(&(fregs)->regs)
+#define ftrace_regs_query_register_offset(name) \
+ regs_query_register_offset(name)
+
struct ftrace_ops;
#define ftrace_graph_func ftrace_graph_func
void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
@@ -126,6 +126,35 @@ static __always_inline struct pt_regs *ftrace_get_regs(struct ftrace_regs *fregs
return arch_ftrace_get_regs(fregs);
}
+/*
+ * When true, the ftrace_regs_{get,set}_*() functions may be used on fregs.
+ * Note: this can be true even when ftrace_get_regs() cannot provide a pt_regs.
+ */
+static __always_inline bool ftrace_regs_has_args(struct ftrace_regs *fregs)
+{
+ if (IS_ENABLED(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS))
+ return true;
+
+ return ftrace_get_regs(fregs) != NULL;
+}
+
+#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
+#define ftrace_regs_get_instruction_pointer(fregs) \
+ instruction_pointer(ftrace_get_regs(fregs))
+#define ftrace_regs_get_argument(fregs, n) \
+ regs_get_kernel_argument(ftrace_get_regs(fregs), n)
+#define ftrace_regs_get_stack_pointer(fregs) \
+ kernel_stack_pointer(ftrace_get_regs(fregs))
+#define ftrace_regs_return_value(fregs) \
+ regs_return_value(ftrace_get_regs(fregs))
+#define ftrace_regs_set_return_value(fregs, ret) \
+ regs_set_return_value(ftrace_get_regs(fregs), ret)
+#define ftrace_override_function_with_return(fregs) \
+ override_function_with_return(ftrace_get_regs(fregs))
+#define ftrace_regs_query_register_offset(name) \
+ regs_query_register_offset(name)
+#endif
+
typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct ftrace_regs *fregs);
@@ -46,10 +46,10 @@ config HAVE_DYNAMIC_FTRACE_WITH_ARGS
bool
help
If this is set, then arguments and stack can be found from
- the pt_regs passed into the function callback regs parameter
+ the ftrace_regs passed into the function callback regs parameter
by default, even without setting the REGS flag in the ftrace_ops.
- This allows for use of regs_get_kernel_argument() and
- kernel_stack_pointer().
+ This allows for use of ftrace_regs_get_argument() and
+ ftrace_regs_get_stack_pointer().
config HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
bool
In subsequent patches we'll arrange for architectures to have an ftrace_regs which is entirely distinct from pt_regs. In preparation for this, we need to minimize the use of pt_regs to where strictly necessary in the core ftrace code. This patch adds new ftrace_regs_{get,set}_*() helpers which can be used to manipulate ftrace_regs. When CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=y, these can always be used on any ftrace_regs, and when CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=n these can be used when regs are available. A new ftrace_regs_has_args(fregs) helper is added which code can use to check when these are usable. Co-developed-by: Florent Revest <revest@chromium.org> Signed-off-by: Florent Revest <revest@chromium.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> --- arch/powerpc/include/asm/ftrace.h | 19 +++++++++++++++++++ arch/s390/include/asm/ftrace.h | 19 +++++++++++++++++++ arch/x86/include/asm/ftrace.h | 16 ++++++++++++++++ include/linux/ftrace.h | 29 +++++++++++++++++++++++++++++ kernel/trace/Kconfig | 6 +++--- 5 files changed, 86 insertions(+), 3 deletions(-)