# git rev-parse -q --verify 86de312343c4b56d699f8ed98aac8bdab1e94225^{commit}
86de312343c4b56d699f8ed98aac8bdab1e94225
already have revision, skipping fetch
# git checkout -q -f -B kisskb 86de312343c4b56d699f8ed98aac8bdab1e94225
# git clean -qxdf
# < git log -1
# commit 86de312343c4b56d699f8ed98aac8bdab1e94225
# 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/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-gcc --version
# < /opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-ld --version
# < git log --format=%s --max-count=1 86de312343c4b56d699f8ed98aac8bdab1e94225
# < make -s -j 48 ARCH=arm64 O=/kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  defconfig
# make -s -j 48 ARCH=arm64 O=/kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4 CROSS_COMPILE=/opt/cross/kisskb/br-aarch64-glibc-2016.08-613-ge98b4dd/bin/aarch64-linux-  
arch/arm64/Makefile:27: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum
arch/arm64/Makefile:40: LSE atomics not supported by binutils
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c: In function 'sh_mobile_i2c_isr':
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:399:26: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized]
   pd->msg->buf[real_pos] = data;
                          ^
/kisskb/src/drivers/i2c/busses/i2c-sh_mobile.c:372:16: note: 'data' was declared here
  unsigned char data;
                ^
In file included from /kisskb/src/include/linux/rwsem.h:16:0,
                 from /kisskb/src/include/linux/notifier.h:15,
                 from /kisskb/src/include/linux/clk.h:17,
                 from /kisskb/src/drivers/tty/serial/sh-sci.c:24:
/kisskb/src/drivers/tty/serial/sh-sci.c: In function 'sci_dma_rx_submit':
/kisskb/src/include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
   _raw_spin_unlock_irqrestore(lock, flags); \
   ^
/kisskb/src/drivers/tty/serial/sh-sci.c:1353:16: note: 'flags' was declared here
  unsigned long flags;
                ^
/kisskb/src/net/ipv4/fib_semantics.c: In function 'fib_check_nh_v4_gw':
/kisskb/src/net/ipv4/fib_semantics.c:1027:12: warning: 'err' may be used uninitialized in this function [-Wmaybe-uninitialized]
   if (!tbl || err) {
            ^
Completed OK
# rm -rf /kisskb/build/powerpc-next_arm64-defconfig_arm64-gcc5.4
# Build took: 0:03:55.487638