riscv: Require FRAME_POINTER for some configurations

Some V configurations implicitly turn on '-fno-omit-frame-pointer',
but leaving FRAME_POINTER disabled. This makes it hard to reason about
the FRAME_POINTER config, and also triggers build failures introduced
in by the commit in the Fixes: tag.

Select FRAME_POINTER explicitly for these configurations.

Fixes: ebc9cb03 ("riscv: stack: Fixup independent softirq stack for CONFIG_FRAME_POINTER=n")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230823082845.354839-1-bjorn@kernel.orgSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/Kconfig

@@ -62,6 +62,7 @@ config RISCV
 	select COMMON_CLK
 	select CPU_PM if CPU_IDLE || HIBERNATION
 	select EDAC_SUPPORT
+	select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE)
 	select GENERIC_ARCH_TOPOLOGY
 	select GENERIC_ATOMIC64 if !64BIT
 	select GENERIC_CLOCKEVENTS_BROADCAST if SMP

arch/riscv/Makefile

@@ -87,9 +87,6 @@ endif
 ifeq ($(CONFIG_CMODEL_MEDANY),y)
 	KBUILD_CFLAGS += -mcmodel=medany
 endif
-ifeq ($(CONFIG_PERF_EVENTS),y)
-        KBUILD_CFLAGS += -fno-omit-frame-pointer
-endif
 
 # Avoid generating .eh_frame sections.
 KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables