# git rev-parse -q --verify 9b1ea29bc0d7b94d420f96a0f4121403efc3dd85^{commit}
9b1ea29bc0d7b94d420f96a0f4121403efc3dd85
already have revision, skipping fetch
# git checkout -q -f -B kisskb 9b1ea29bc0d7b94d420f96a0f4121403efc3dd85
# git clean -qxdf
# < git log -1
# commit 9b1ea29bc0d7b94d420f96a0f4121403efc3dd85
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Wed Mar 10 10:18:04 2021 -0800
# 
#     Revert "mm, slub: consider rest of partial list if acquire_slab() fails"
#     
#     This reverts commit 8ff60eb052eeba95cfb3efe16b08c9199f8121cf.
#     
#     The kernel test robot reports a huge performance regression due to the
#     commit, and the reason seems fairly straightforward: when there is
#     contention on the page list (which is what causes acquire_slab() to
#     fail), we do _not_ want to just loop and try again, because that will
#     transfer the contention to the 'n->list_lock' spinlock we hold, and
#     just make things even worse.
#     
#     This is admittedly likely a problem only on big machines - the kernel
#     test robot report comes from a 96-thread dual socket Intel Xeon Gold
#     6252 setup, but the regression there really is quite noticeable:
#     
#        -47.9% regression of stress-ng.rawpkt.ops_per_sec
#     
#     and the commit that was marked as being fixed (7ced37197196: "slub:
#     Acquire_slab() avoid loop") actually did the loop exit early very
#     intentionally (the hint being that "avoid loop" part of that commit
#     message), exactly to avoid this issue.
#     
#     The correct thing to do may be to pick some kind of reasonable middle
#     ground: instead of breaking out of the loop on the very first sign of
#     contention, or trying over and over and over again, the right thing may
#     be to re-try _once_, and then give up on the second failure (or pick
#     your favorite value for "once"..).
#     
#     Reported-by: kernel test robot <oliver.sang@intel.com>
#     Link: https://lore.kernel.org/lkml/20210301080404.GF12822@xsang-OptiPlex-9020/
#     Cc: Jann Horn <jannh@google.com>
#     Cc: David Rientjes <rientjes@google.com>
#     Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
#     Acked-by: Christoph Lameter <cl@linux.com>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-ld --version
# < git log --format=%s --max-count=1 9b1ea29bc0d7b94d420f96a0f4121403efc3dd85
# < make -s -j 120 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-  randconfig
KCONFIG_SEED=0xC9D36F26
# Added to kconfig CONFIG_PREVENT_FIRMWARE_BUILD=y
# < make -s -j 120 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-  help
# make -s -j 120 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-  olddefconfig
# make -s -j 120 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-  
/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-ld: Unexpected GOT/PLT entries detected!
/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-ld: Unexpected run-time procedure linkages detected!
drivers/gpu/drm/rcar-du/rcar_du_crtc.o: In function `rcar_du_cmm_setup':
rcar_du_crtc.c:(.text+0x244): undefined reference to `rcar_cmm_setup'
drivers/gpu/drm/rcar-du/rcar_du_crtc.o: In function `rcar_du_crtc_atomic_enable':
rcar_du_crtc.c:(.text+0x1804): undefined reference to `rcar_cmm_enable'
drivers/gpu/drm/rcar-du/rcar_du_crtc.o: In function `rcar_du_crtc_atomic_disable':
rcar_du_crtc.c:(.text+0x1d2c): undefined reference to `rcar_cmm_disable'
drivers/gpu/drm/rcar-du/rcar_du_kms.o: In function `rcar_du_modeset_init':
rcar_du_kms.c:(.text+0xcac): undefined reference to `rcar_cmm_init'
drivers/gpu/drm/pl111/pl111_versatile.o: In function `pl111_versatile_init':
pl111_versatile.c:(.text+0x698): undefined reference to `devm_regmap_init_vexpress_config'
make[1]: *** [/kisskb/src/Makefile:1197: vmlinux] Error 1
make: *** [Makefile:215: __sub-make] Error 2
Command 'make -s -j 120 ARCH=arm64 O=/kisskb/build/linus-rand_arm64-randconfig_arm64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux-  ' returned non-zero exit status 2
# rm -rf /kisskb/build/linus-rand_arm64-randconfig_arm64-gcc8
# Build took: 0:02:54.391869