# git rev-parse -q --verify 3fe3a16489c3d45bdd9d5a7e2d13f2fbbd236cbf^{commit}
# git fetch -q -n -f git://gitlab.ozlabs.ibm.com/linuxppc/linux.git next-test
# git rev-parse -q --verify 3fe3a16489c3d45bdd9d5a7e2d13f2fbbd236cbf^{commit}
3fe3a16489c3d45bdd9d5a7e2d13f2fbbd236cbf
# git checkout -q -f -B kisskb 3fe3a16489c3d45bdd9d5a7e2d13f2fbbd236cbf
# git clean -qxdf
# < git log -1
# commit 3fe3a16489c3d45bdd9d5a7e2d13f2fbbd236cbf
# Author: Christophe Leroy <christophe.leroy@csgroup.eu>
# Date:   Mon Aug 15 21:48:40 2022 +1000
# 
#     powerpc/code-patching: Speed up page mapping/unmapping
#     
#     Since commit 591b4b268435 ("powerpc/code-patching: Pre-map patch area")
#     the patch area is premapped so intermediate page tables are already
#     allocated.
#     
#     Use __set_pte_at() directly instead of the heavy map_kernel_page(),
#     at for unmapping just do a pte_clear() followed by a flush.
#     
#     __set_pte_at() can be used directly without the filters in
#     set_pte_at() because we are mapping a normal page non executable.
#     
#     Make sure gcc knows text_poke_area is page aligned in order to
#     optimise the flush.
#     
#     This change reduces by 66% the time needed to activate ftrace on
#     an 8xx (588000 tb ticks instead of 1744000).
#     
#     Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
#     [mpe: Add ptesync needed on radix to avoid spurious fault]
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Link: https://lore.kernel.org/r/20220815114840.1468656-1-mpe@ellerman.id.au
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-ld --version
# < git log --format=%s --max-count=1 3fe3a16489c3d45bdd9d5a7e2d13f2fbbd236cbf
# < make -s -j 48 ARCH=m68k O=/kisskb/build/powerpc-next_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  defconfig
# < make -s -j 48 ARCH=m68k O=/kisskb/build/powerpc-next_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  help
# make -s -j 48 ARCH=m68k O=/kisskb/build/powerpc-next_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  olddefconfig
# make -s -j 48 ARCH=m68k O=/kisskb/build/powerpc-next_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/m68k-linux/bin/m68k-linux-  
Completed OK
# rm -rf /kisskb/build/powerpc-next_m68k-defconfig_m68k-gcc8
# Build took: 0:03:02.202024