[PATCH] csky: fix syscache.c fallthrough warning

[PATCH] csky: fix syscache.c fallthrough warning

[Randy Dunlap]

This case of the switch statement falls through to the following case.
This appears to be on purpose, so declare it as OK.

../arch/csky/mm/syscache.c: In function '__do_sys_cacheflush':
../arch/csky/mm/syscache.c:17:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
   17 |   flush_icache_mm_range(current->mm,
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   18 |     (unsigned long)addr,
      |     ~~~~~~~~~~~~~~~~~~~~
   19 |     (unsigned long)addr + bytes);
      |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../arch/csky/mm/syscache.c:20:2: note: here
   20 |  case DCACHE:
      |  ^~~~

Fixes: 997153b9a75c ("csky: Add flush_icache_mm to defer flush icache all")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: linux-csky@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
---
@Guo, should this be a "break" instead of fallthrough?

 arch/csky/mm/syscache.c |    1 +
 1 file changed, 1 insertion(+)

--- linux-next-20210409.orig/arch/csky/mm/syscache.c
+++ linux-next-20210409/arch/csky/mm/syscache.c
@@ -17,6 +17,7 @@ SYSCALL_DEFINE3(cacheflush,
 		flush_icache_mm_range(current->mm,
 				(unsigned long)addr,
 				(unsigned long)addr + bytes);
+		fallthrough;
 	case DCACHE:
 		dcache_wb_range((unsigned long)addr,
 				(unsigned long)addr + bytes);

Re: [PATCH] csky: fix syscache.c fallthrough warning

[Guo Ren]

Acked-by: Guo Ren <guoren@kernel.org>

It's a fallthrough is for BCACHE, but affects ICACHE with more
expensive. I'll fix up it later.

        }

On Mon, Apr 12, 2021 at 12:41 AM Randy Dunlap <rdunlap@infradead.org> wrote:
>
> This case of the switch statement falls through to the following case.
> This appears to be on purpose, so declare it as OK.
>
> ../arch/csky/mm/syscache.c: In function '__do_sys_cacheflush':
> ../arch/csky/mm/syscache.c:17:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
>    17 |   flush_icache_mm_range(current->mm,
>       |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>    18 |     (unsigned long)addr,
>       |     ~~~~~~~~~~~~~~~~~~~~
>    19 |     (unsigned long)addr + bytes);
>       |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ../arch/csky/mm/syscache.c:20:2: note: here
>    20 |  case DCACHE:
>       |  ^~~~
>
> Fixes: 997153b9a75c ("csky: Add flush_icache_mm to defer flush icache all")
> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
> Cc: Guo Ren <guoren@kernel.org>
> Cc: linux-csky@vger.kernel.org
> Cc: Arnd Bergmann <arnd@arndb.de>
> ---
> @Guo, should this be a "break" instead of fallthrough?
>
>  arch/csky/mm/syscache.c |    1 +
>  1 file changed, 1 insertion(+)
>
> --- linux-next-20210409.orig/arch/csky/mm/syscache.c
> +++ linux-next-20210409/arch/csky/mm/syscache.c
> @@ -17,6 +17,7 @@ SYSCALL_DEFINE3(cacheflush,
>                 flush_icache_mm_range(current->mm,
>                                 (unsigned long)addr,
>                                 (unsigned long)addr + bytes);
> +               fallthrough;
>         case DCACHE:
>                 dcache_wb_range((unsigned long)addr,
>                                 (unsigned long)addr + bytes);



--
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/