diff options
| author | Florent Revest <revest@chromium.org> | 2023-03-21 15:04:23 +0100 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2023-03-21 13:43:32 -0400 |
| commit | 60c8971899f3b34ad24857913c0784dab08962f0 (patch) | |
| tree | 28785232fe1c7b386d6ca86f1ef616347a41127b | |
| parent | dbaccb618fabde8b8596e341f8d76da63a9b0c2f (diff) | |
ftrace: Make DIRECT_CALLS work WITH_ARGS and !WITH_REGS
Direct called trampolines can be called in two ways:
- either from the ftrace callsite. In this case, they do not access any
struct ftrace_regs nor pt_regs
- Or, if a ftrace ops is also attached, from the end of a ftrace
trampoline. In this case, the call_direct_funcs ops is in charge of
setting the direct call trampoline's address in a struct ftrace_regs
Since:
commit 9705bc709604 ("ftrace: pass fregs to arch_ftrace_set_direct_caller()")
The later case no longer requires a full pt_regs. It only needs a struct
ftrace_regs so DIRECT_CALLS can work with both WITH_ARGS or WITH_REGS.
With architectures like arm64 already abandoning WITH_REGS in favor of
WITH_ARGS, it's important to have DIRECT_CALLS work WITH_ARGS only.
Link: https://lkml.kernel.org/r/20230321140424.345218-7-revest@chromium.org
Signed-off-by: Florent Revest <revest@chromium.org>
Co-developed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
| -rw-r--r-- | include/linux/ftrace.h | 6 | ||||
| -rw-r--r-- | kernel/trace/Kconfig | 2 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 2 |
3 files changed, 8 insertions, 2 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 6a532dd6789e..31f1e1df2af3 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -241,6 +241,12 @@ enum { FTRACE_OPS_FL_DIRECT = BIT(17), }; +#ifndef CONFIG_DYNAMIC_FTRACE_WITH_ARGS +#define FTRACE_OPS_FL_SAVE_ARGS FTRACE_OPS_FL_SAVE_REGS +#else +#define FTRACE_OPS_FL_SAVE_ARGS 0 +#endif + /* * FTRACE_OPS_CMD_* commands allow the ftrace core logic to request changes * to a ftrace_ops. Note, the requests may fail. diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index a856d4a34c67..5b1e7fa41ca8 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -257,7 +257,7 @@ config DYNAMIC_FTRACE_WITH_REGS config DYNAMIC_FTRACE_WITH_DIRECT_CALLS def_bool y - depends on DYNAMIC_FTRACE_WITH_REGS + depends on DYNAMIC_FTRACE_WITH_REGS || DYNAMIC_FTRACE_WITH_ARGS depends on HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS config DYNAMIC_FTRACE_WITH_CALL_OPS diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 3bef2abc037a..3b46dba3f69b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5288,7 +5288,7 @@ static LIST_HEAD(ftrace_direct_funcs); static int register_ftrace_function_nolock(struct ftrace_ops *ops); -#define MULTI_FLAGS (FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_REGS) +#define MULTI_FLAGS (FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_ARGS) static int check_direct_multi(struct ftrace_ops *ops) { |