# git rev-parse -q --verify d909f9109c301f4e9e41678025c45d719ab8f7d7^{commit}
d909f9109c301f4e9e41678025c45d719ab8f7d7
already have revision, skipping fetch
# git checkout -q -f -B kisskb d909f9109c301f4e9e41678025c45d719ab8f7d7
# git clean -qxdf
# < git log -1
# commit d909f9109c301f4e9e41678025c45d719ab8f7d7
# Author: Nicholas Piggin <npiggin@gmail.com>
# Date:   Mon Jun 10 13:08:18 2019 +1000
# 
#     powerpc/64s/radix: Enable HAVE_ARCH_HUGE_VMAP
#     
#     This sets the HAVE_ARCH_HUGE_VMAP option, and defines the required
#     page table functions.
#     
#     This enables huge (2MB and 1GB) ioremap mappings. I don't have a
#     benchmark for this change, but huge vmap will be used by a later core
#     kernel change to enable huge vmalloc memory mappings. This improves
#     cached `git diff` performance by about 5% on a 2-node POWER9 with 32MB
#     size dentry cache hash.
#     
#       Profiling git diff dTLB misses with a vanilla kernel:
#     
#       81.75%  git      [kernel.vmlinux]    [k] __d_lookup_rcu
#        7.21%  git      [kernel.vmlinux]    [k] strncpy_from_user
#        1.77%  git      [kernel.vmlinux]    [k] find_get_entry
#        1.59%  git      [kernel.vmlinux]    [k] kmem_cache_free
#     
#                 40,168      dTLB-miss
#            0.100342754 seconds time elapsed
#     
#       With powerpc huge vmalloc:
#     
#                  2,987      dTLB-miss
#            0.095933138 seconds time elapsed
#     
#     Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /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 d909f9109c301f4e9e41678025c45d719ab8f7d7
# < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_ps3_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  ps3_defconfig
# make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_ps3_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
In file included from /kisskb/src/include/linux/genhd.h:67:0,
                 from /kisskb/src/include/linux/blkdev.h:11,
                 from /kisskb/src/drivers/block/ps3vram.c:12:
/kisskb/src/drivers/block/ps3vram.c: In function 'ps3vram_probe':
/kisskb/src/drivers/block/ps3vram.c:770:23: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'sector_t {aka long long unsigned int}' [-Wformat=]
  dev_info(&dev->core, "%s: Using %lu MiB of GPU memory\n",
                       ^
/kisskb/src/include/linux/device.h:1400:22: note: in definition of macro 'dev_fmt'
 #define dev_fmt(fmt) fmt
                      ^
/kisskb/src/drivers/block/ps3vram.c:770:2: note: in expansion of macro 'dev_info'
  dev_info(&dev->core, "%s: Using %lu MiB of GPU memory\n",
  ^
Completed OK
# rm -rf /kisskb/build/powerpc-next_ps3_defconfig_powerpc-gcc5
# Build took: 0:01:40.970771