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| author | Florent Revest <revest@chromium.org> | 2023-03-21 15:04:23 +0100 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2023-03-21 18:43:32 +0100 |
| commit | 60c8971899f3b34ad24857913c0784dab08962f0 (patch) | |
| tree | 28785232fe1c7b386d6ca86f1ef616347a41127b /kernel/trace/ftrace.c | |
| parent | ftrace: Store direct called addresses in their ops (diff) | |
| download | linux-60c8971899f3b34ad24857913c0784dab08962f0.tar.xz linux-60c8971899f3b34ad24857913c0784dab08962f0.zip | |
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>
Diffstat (limited to 'kernel/trace/ftrace.c')
| -rw-r--r-- | kernel/trace/ftrace.c | 2 |
1 files changed, 1 insertions, 1 deletions
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) { |