# git rev-parse -q --verify d0d283b05eee6a6c51df527e077d513ac2734d95^{commit} d0d283b05eee6a6c51df527e077d513ac2734d95 already have revision, skipping fetch # git checkout -q -f -B kisskb d0d283b05eee6a6c51df527e077d513ac2734d95 # git clean -qxdf # < git log -1 # commit d0d283b05eee6a6c51df527e077d513ac2734d95 # Author: Naveen N Rao # Date: Mon Jun 19 15:17:34 2023 +0530 # # powerpc/ftrace: Add support for -fpatchable-function-entry # # GCC v13.1 updated support for -fpatchable-function-entry on ppc64le to # emit nops after the local entry point, rather than before it. This # allows us to use this in the kernel for ftrace purposes. A new script is # added under arch/powerpc/tools/ to help detect if nops are emitted after # the function local entry point, or before the global entry point. # # With -fpatchable-function-entry, we no longer have the profiling # instructions generated at function entry, so we only need to validate # the presence of two nops at the ftrace location in ftrace_init_nop(). We # patch the preceding instruction with 'mflr r0' to match the # -mprofile-kernel ABI for subsequent ftrace use. # # This changes the profiling instructions used on ppc32. The default -pg # option emits an additional 'stw' instruction after 'mflr r0' and before # the branch to _mcount 'bl _mcount'. This is very similar to the original # -mprofile-kernel implementation on ppc64le, where an additional 'std' # instruction was used to save LR to its save location in the caller's # stackframe. Subsequently, this additional store was removed in later # compiler versions for performance reasons. The same reasons apply for # ppc32 so we only patch in a 'mflr r0'. # # Signed-off-by: Naveen N Rao # Reviewed-by: Christophe Leroy # Signed-off-by: Michael Ellerman # Link: https://msgid.link/68586d22981a2c3bb45f27a2b621173d10a7d092.1687166935.git.naveen@kernel.org # < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 d0d283b05eee6a6c51df527e077d513ac2734d95 # make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-next_44x_arches_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- 44x/arches_defconfig # < make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-next_44x_arches_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-next_44x_arches_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig # make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-next_44x_arches_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- Completed OK # rm -rf /kisskb/build/powerpc-next_44x_arches_defconfig_powerpc-gcc5 # Build took: 0:00:31.351118