• AKASHI Takahiro's avatar
    ftrace: Add arm64 support to recordmcount · af64d2aa
    AKASHI Takahiro authored
    Recordmcount utility under scripts is run, after compiling each object,
    to find out all the locations of calling _mcount() and put them into
    specific seciton named __mcount_loc.
    Then linker collects all such information into a table in the kernel image
    (between __start_mcount_loc and __stop_mcount_loc) for later use by ftrace.
    
    This patch adds arm64 specific definitions to identify such locations.
    There are two types of implementation, C and Perl. On arm64, only C version
    is used to build the kernel now that CONFIG_HAVE_C_RECORDMCOUNT is on.
    But Perl version is also maintained.
    
    This patch also contains a workaround just in case where a header file,
    elf.h, on host machine doesn't have definitions of EM_AARCH64 nor
    R_AARCH64_ABS64. Without them, compiling C version of recordmcount will
    fail.
    Acked-by: default avatarWill Deacon <will.deacon@arm.com>
    Signed-off-by: default avatarAKASHI Takahiro <takahiro.akashi@linaro.org>
    Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
    af64d2aa
recordmcount.c 12.5 KB