[PATCH] riscv: Stop supporting static ftrace

[PATCH] riscv: Stop supporting static ftrace

[Alexandre Ghiti]

Now that DYNAMIC_FTRACE was introduced, there is no need to support
static ftrace as it is way less performant. This simplifies the code and
prevents build failures as reported by kernel test robot when
!DYNAMIC_FTRACE.

Also make sure that FUNCTION_TRACER can only be selected if
DYNAMIC_FTRACE is supported (we have a dependency on the toolchain).

Co-developed-by: chenmiao <chenmiao.ku@gmail.com>
Signed-off-by: chenmiao <chenmiao.ku@gmail.com>
Fixes: b2137c3b6d7a ("riscv: ftrace: prepare ftrace for atomic code patching")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202506191949.o3SMu8Zn-lkp@intel.com/
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
---
 arch/riscv/Kconfig | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index d71ea0f4466fc3eefd1bd89f37637193d9a464da..1c5544401530fed9ecade4dd11c1c33a0bd6a2da 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -98,6 +98,7 @@ config RISCV
 	select CLONE_BACKWARDS
 	select COMMON_CLK
 	select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND
+	select DYNAMIC_FTRACE if FUNCTION_TRACER
 	select EDAC_SUPPORT
 	select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE)
 	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE
@@ -162,7 +163,7 @@ config RISCV
 	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
 	select HAVE_FUNCTION_GRAPH_TRACER if HAVE_DYNAMIC_FTRACE_WITH_ARGS
 	select HAVE_FUNCTION_GRAPH_FREGS
-	select HAVE_FUNCTION_TRACER if !XIP_KERNEL
+	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && HAVE_DYNAMIC_FTRACE
 	select HAVE_EBPF_JIT if MMU
 	select HAVE_GUP_FAST if MMU
 	select HAVE_FUNCTION_ARG_ACCESS_API

---
base-commit: 5bd6225da2e2d8bbf2b6713fde42159f85ad3fdb
change-id: 20250716-dev-alex-static_ftrace-882f0d8357bf

Best regards,
-- 
Alexandre Ghiti <alexghiti@rivosinc.com>

Re: [PATCH] riscv: Stop supporting static ftrace

[patchwork-bot+linux-riscv]

Hello:

This patch was applied to riscv/linux.git (fixes)
by Palmer Dabbelt <palmer@dabbelt.com>:

On Wed, 16 Jul 2025 12:05:16 +0000 you wrote:
> Now that DYNAMIC_FTRACE was introduced, there is no need to support
> static ftrace as it is way less performant. This simplifies the code and
> prevents build failures as reported by kernel test robot when
> !DYNAMIC_FTRACE.
> 
> Also make sure that FUNCTION_TRACER can only be selected if
> DYNAMIC_FTRACE is supported (we have a dependency on the toolchain).
> 
> [...]

Here is the summary with links:
  - riscv: Stop supporting static ftrace
    https://git.kernel.org/riscv/c/5874ca4c6280

You are awesome, thank you!
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