diff options
| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-11-08 13:07:06 -0500 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-11-13 09:36:41 -0500 |
| commit | 763e34e74bb7d5c316015e2e39fcc8520bfd071c (patch) | |
| tree | 0fc9886f242a9c91c3ab0d1234db71a6da2a010a /kernel/trace/Kconfig | |
| parent | 7e16f581a81759bafea04d049134b32d1a881226 (diff) | |
ftrace: Add register_ftrace_direct()
Add the start of the functionality to allow other trampolines to use the
ftrace mcount/fentry/nop location. This adds two new functions:
register_ftrace_direct() and unregister_ftrace_direct()
Both take two parameters: the first is the instruction address of where the
mcount/fentry/nop exists, and the second is the trampoline to have that
location called.
This will handle cases where ftrace is already used on that same location,
and will make it still work, where the registered direct called trampoline
will get called after all the registered ftrace callers are handled.
Currently, it will not allow for IP_MODIFY functions to be called at the
same locations, which include some kprobes and live kernel patching.
At this point, no architecture supports this. This is only the start of
implementing the framework.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/Kconfig')
| -rw-r--r-- | kernel/trace/Kconfig | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index e08527f50d2a..624a05e99b0b 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -33,6 +33,9 @@ config HAVE_DYNAMIC_FTRACE config HAVE_DYNAMIC_FTRACE_WITH_REGS bool +config HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + bool + config HAVE_FTRACE_MCOUNT_RECORD bool help @@ -557,6 +560,11 @@ config DYNAMIC_FTRACE_WITH_REGS depends on DYNAMIC_FTRACE depends on HAVE_DYNAMIC_FTRACE_WITH_REGS +config DYNAMIC_FTRACE_WITH_DIRECT_CALLS + def_bool y + depends on DYNAMIC_FTRACE + depends on HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + config FUNCTION_PROFILER bool "Kernel function profiler" depends on FUNCTION_TRACER |