Re: mm/munlock: mlock_page() munlock_page() batch by pagevec

The following build regression noticed while building Linux next 20220209 arm/riscv/sh of allnoconfig and tinyconfig builds failed with gcc-10, gcc-11 and clang-13.

clang: warning: argument unused during compilation: '-march=armv7-m' [-Wunused-command-line-argument] mm/swap.c:637:2: error: implicit declaration of function 'mlock_page_drain' [-Werror,-Wimplicit-function-declaration] mlock_page_drain(cpu); ^ 1 error generated. make[2]: *** [scripts/Makefile.build:289: mm/swap.o] Error 1

Reported-by: Linux Kernel Functional Testing lkft@linaro.org

-- Linaro LKFT https://lkft.linaro.org