[V8,1/4] riscv: select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY

Commit Message

Song Shuai March 24, 2023, 3:33 a.m. UTC

In RISC-V, -fpatchable-function-entry option is used to support
dynamic ftrace in this commit afc76b8b8011 ("riscv: Using
PATCHABLE_FUNCTION_ENTRY instead of MCOUNT"). So recordmcount
don't have to be called to create the __mcount_loc section before
the vmlinux linking.

Here selects FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY to tell
Makefile not to run recordmcount.

Link: https://lore.kernel.org/linux-riscv/CAAYs2=[e-mail]/T/#t
Link: https://lore.kernel.org/linux-riscv/Y4jtfrJt+%2FQ5nMOz@spud/
Signed-off-by: Song Shuai <[e-mail]>
Tested-by: Guo Ren <[e-mail]>
Signed-off-by: Guo Ren <[e-mail]>
---
 arch/riscv/Kconfig | 1 +
 1 file changed, 1 insertion(+)

Comments

Björn Töpel May 10, 2023, 7:09 a.m. UTC | #1

Song Shuai <[e-mail]> writes:

> In RISC-V, -fpatchable-function-entry option is used to support
> dynamic ftrace in this commit afc76b8b8011 ("riscv: Using
> PATCHABLE_FUNCTION_ENTRY instead of MCOUNT"). So recordmcount
> don't have to be called to create the __mcount_loc section before
> the vmlinux linking.
>
> Here selects FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY to tell
> Makefile not to run recordmcount.
>
> Link: https://lore.kernel.org/linux-riscv/CAAYs2=[e-mail]/T/#t
> Link: https://lore.kernel.org/linux-riscv/Y4jtfrJt+%2FQ5nMOz@spud/
> Signed-off-by: Song Shuai <[e-mail]>
> Tested-by: Guo Ren <[e-mail]>
> Signed-off-by: Guo Ren <[e-mail]>

Acked-by: Björn Töpel <[e-mail]>

Patch

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c5e42cc37604..93d4817c9d73 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -56,6 +56,7 @@  config RISCV
 	select COMMON_CLK
 	select CPU_PM if CPU_IDLE
 	select EDAC_SUPPORT
+	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE
 	select GENERIC_ARCH_TOPOLOGY
 	select GENERIC_ATOMIC64 if !64BIT
 	select GENERIC_CLOCKEVENTS_BROADCAST if SMP