From: Xu Kuohai <xukuohai@xxxxxxxxxx> To support ftrace direct call on arm64, multiple NOP instructions need to be added to the ftrace fentry, which will make the kernel image larger. For users who don't need direct calls, they should not pay this unnecessary price, so they should be allowed to disable this option. Signed-off-by: Xu Kuohai <xukuohai@xxxxxxxxxx> --- kernel/trace/Kconfig | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 1052126bdca2..fc8a22f1a6a0 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -240,9 +240,14 @@ config DYNAMIC_FTRACE_WITH_REGS depends on HAVE_DYNAMIC_FTRACE_WITH_REGS config DYNAMIC_FTRACE_WITH_DIRECT_CALLS - def_bool y + bool "Support for calling custom trampoline from fentry directly" + default y depends on DYNAMIC_FTRACE_WITH_REGS depends on HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + help + This option enables calling custom trampoline from ftrace fentry + directly, instead of using ftrace regs caller. This may reserve more + space in the fentry, making the kernel image larger. config DYNAMIC_FTRACE_WITH_ARGS def_bool y -- 2.30.2
