# git rev-parse -q --verify b91e1302ad9b80c174a4855533f7e3aa2873355e^{commit}
b91e1302ad9b80c174a4855533f7e3aa2873355e
already have revision, skipping fetch
# git checkout -q -f -B kisskb b91e1302ad9b80c174a4855533f7e3aa2873355e
# git clean -qxdf
# git log -1
commit b91e1302ad9b80c174a4855533f7e3aa2873355e
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue Dec 27 11:40:38 2016 -0800

    mm: optimize PageWaiters bit use for unlock_page()
    
    In commit 62906027091f ("mm: add PageWaiters indicating tasks are
    waiting for a page bit") Nick Piggin made our page locking no longer
    unconditionally touch the hashed page waitqueue, which not only helps
    performance in general, but is particularly helpful on NUMA machines
    where the hashed wait queues can bounce around a lot.
    
    However, the "clear lock bit atomically and then test the waiters bit"
    sequence turns out to be much more expensive than it needs to be,
    because you get a nasty stall when trying to access the same word that
    just got updated atomically.
    
    On architectures where locking is done with LL/SC, this would be trivial
    to fix with a new primitive that clears one bit and tests another
    atomically, but that ends up not working on x86, where the only atomic
    operations that return the result end up being cmpxchg and xadd.  The
    atomic bit operations return the old value of the same bit we changed,
    not the value of an unrelated bit.
    
    On x86, we could put the lock bit in the high bit of the byte, and use
    "xadd" with that bit (where the overflow ends up not touching other
    bits), and look at the other bits of the result.  However, an even
    simpler model is to just use a regular atomic "and" to clear the lock
    bit, and then the sign bit in eflags will indicate the resulting state
    of the unrelated bit #7.
    
    So by moving the PageWaiters bit up to bit #7, we can atomically clear
    the lock bit and test the waiters bit on x86 too.  And architectures
    with LL/SC (which is all the usual RISC suspects), the particular bit
    doesn't matter, so they are fine with this approach too.
    
    This avoids the extra access to the same atomic word, and thus avoids
    the costly stall at page unlock time.
    
    The only downside is that the interface ends up being a bit odd and
    specialized: clear a bit in a byte, and test the sign bit.  Nick doesn't
    love the resulting name of the new primitive, but I'd rather make the
    name be descriptive and very clear about the limitation imposed by
    trying to work across all relevant architectures than make it be some
    generic thing that doesn't make the odd semantics explicit.
    
    So this introduces the new architecture primitive
    
        clear_bit_unlock_is_negative_byte();
    
    and adds the trivial implementation for x86.  We have a generic
    non-optimized fallback (that just does a "clear_bit()"+"test_bit(7)"
    combination) which can be overridden by any architecture that can do
    better.  According to Nick, Power has the same hickup x86 has, for
    example, but some other architectures may not even care.
    
    All these optimizations mean that my page locking stress-test (which is
    just executing a lot of small short-lived shell scripts: "make test" in
    the git source tree) no longer makes our page locking look horribly bad.
    Before all these optimizations, just the unlock_page() costs were just
    over 3% of all CPU overhead on "make test".  After this, it's down to
    0.66%, so just a quarter of the cost it used to be.
    
    (The difference on NUMA is bigger, but there this micro-optimization is
    likely less noticeable, since the big issue on NUMA was not the accesses
    to 'struct page', but the waitqueue accesses that were already removed
    by Nick's earlier commit).
    
    Acked-by: Nick Piggin <npiggin@gmail.com>
    Cc: Dave Hansen <dave.hansen@linux.intel.com>
    Cc: Bob Peterson <rpeterso@redhat.com>
    Cc: Steven Whitehouse <swhiteho@redhat.com>
    Cc: Andrew Lutomirski <luto@kernel.org>
    Cc: Andreas Gruenbacher <agruenba@redhat.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Mel Gorman <mgorman@techsingularity.net>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-gcc --version
# < git log --format=%s --max-count=1 b91e1302ad9b80c174a4855533f7e3aa2873355e
# < make -j 10 ARCH=arm O=/home/kisskb/slave/build/linus_mv78xx0_defconfig_arm CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-  mv78xx0_defconfig
# make -j 10 ARCH=arm O=/home/kisskb/slave/build/linus_mv78xx0_defconfig_arm CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-  
make[1]: Entering directory '/home/kisskb/slave/build/linus_mv78xx0_defconfig_arm'
  GEN     ./Makefile
scripts/kconfig/conf  --silentoldconfig Kconfig
  CHK     include/config/kernel.release
  SYSHDR  arch/arm/include/generated/uapi/asm/unistd-common.h
  SYSHDR  arch/arm/include/generated/uapi/asm/unistd-oabi.h
  SYSHDR  arch/arm/include/generated/uapi/asm/unistd-eabi.h
  GEN     ./Makefile
  WRAP    arch/arm/include/generated/asm/bitsperlong.h
  WRAP    arch/arm/include/generated/asm/clkdev.h
  WRAP    arch/arm/include/generated/asm/current.h
  WRAP    arch/arm/include/generated/asm/cputime.h
  WRAP    arch/arm/include/generated/asm/early_ioremap.h
  WRAP    arch/arm/include/generated/asm/emergency-restart.h
  WRAP    arch/arm/include/generated/asm/errno.h
  WRAP    arch/arm/include/generated/asm/exec.h
  WRAP    arch/arm/include/generated/asm/ioctl.h
  WRAP    arch/arm/include/generated/asm/ipcbuf.h
  WRAP    arch/arm/include/generated/asm/irq_regs.h
  WRAP    arch/arm/include/generated/asm/kdebug.h
  WRAP    arch/arm/include/generated/asm/local.h
  WRAP    arch/arm/include/generated/asm/local64.h
  WRAP    arch/arm/include/generated/asm/mm-arch-hooks.h
  WRAP    arch/arm/include/generated/asm/msgbuf.h
  WRAP    arch/arm/include/generated/asm/msi.h
  WRAP    arch/arm/include/generated/asm/param.h
  WRAP    arch/arm/include/generated/asm/parport.h
  WRAP    arch/arm/include/generated/asm/poll.h
  CHK     include/generated/uapi/linux/version.h
  WRAP    arch/arm/include/generated/asm/preempt.h
  WRAP    arch/arm/include/generated/asm/resource.h
  WRAP    arch/arm/include/generated/asm/rwsem.h
  WRAP    arch/arm/include/generated/asm/seccomp.h
  WRAP    arch/arm/include/generated/asm/segment.h
  UPD     include/generated/uapi/linux/version.h
  WRAP    arch/arm/include/generated/asm/sembuf.h
  WRAP    arch/arm/include/generated/asm/serial.h
  WRAP    arch/arm/include/generated/asm/shmbuf.h
  WRAP    arch/arm/include/generated/asm/siginfo.h
  WRAP    arch/arm/include/generated/asm/simd.h
  WRAP    arch/arm/include/generated/asm/sizes.h
  WRAP    arch/arm/include/generated/asm/socket.h
  WRAP    arch/arm/include/generated/asm/sockios.h
  WRAP    arch/arm/include/generated/asm/termbits.h
  WRAP    arch/arm/include/generated/asm/termios.h
  WRAP    arch/arm/include/generated/asm/timex.h
  WRAP    arch/arm/include/generated/asm/trace_clock.h
  WRAP    arch/arm/include/generated/asm/unaligned.h
  UPD     include/config/kernel.release
  Using /home/kisskb/slave/src as source for kernel
  CHK     include/generated/utsrelease.h
  UPD     include/generated/utsrelease.h
  HOSTCC  scripts/dtc/dtc.o
  HOSTCC  scripts/kallsyms
  CC      scripts/mod/empty.o
  HOSTCC  scripts/mod/mk_elfconfig
  CC      scripts/mod/devicetable-offsets.s
  HOSTCC  scripts/sortextable
  HOSTCC  scripts/dtc/flattree.o
  HOSTCC  scripts/dtc/fstree.o
  HOSTCC  scripts/dtc/data.o
  GEN     scripts/mod/devicetable-offsets.h
  HOSTCC  scripts/dtc/livetree.o
  HOSTCC  scripts/dtc/treesource.o
  MKELF   scripts/mod/elfconfig.h
  HOSTCC  scripts/mod/modpost.o
  HOSTCC  scripts/dtc/srcpos.o
  HOSTCC  scripts/dtc/checks.o
  HOSTCC  scripts/dtc/util.o
  SHIPPED scripts/dtc/dtc-lexer.lex.c
  SYSNR   arch/arm/include/generated/asm/unistd-nr.h
  GEN     arch/arm/include/generated/asm/mach-types.h
  SYSTBL  arch/arm/include/generated/calls-oabi.S
  SYSTBL  arch/arm/include/generated/calls-eabi.S
  SHIPPED scripts/dtc/dtc-parser.tab.h
  HOSTCC  scripts/mod/file2alias.o
  HOSTCC  scripts/mod/sumversion.o
  SHIPPED scripts/dtc/dtc-parser.tab.c
  CC      kernel/bounds.s
  CHK     include/generated/timeconst.h
  UPD     include/generated/timeconst.h
  HOSTCC  scripts/dtc/dtc-lexer.lex.o
  CHK     include/generated/bounds.h
  UPD     include/generated/bounds.h
  CC      arch/arm/kernel/asm-offsets.s
  HOSTCC  scripts/dtc/dtc-parser.tab.o
  CHK     include/generated/asm-offsets.h
  UPD     include/generated/asm-offsets.h
  CALL    /home/kisskb/slave/src/scripts/checksyscalls.sh
  HOSTLD  scripts/dtc/dtc
  HOSTLD  scripts/mod/modpost
  LD      usr/built-in.o
  CHK     include/generated/compile.h
  CC      init/main.o
  CC      init/do_mounts.o
  CC      init/noinitramfs.o
  CC      init/calibrate.o
  CC      init/init_task.o
  CC      arch/arm/vfp/vfpmodule.o
  AS      arch/arm/vfp/entry.o
  UPD     include/generated/compile.h
  CC      arch/arm/common/firmware.o
  CC      arch/arm/mm/dma-mapping.o
  CC      arch/arm/kernel/elf.o
  AS      arch/arm/kernel/entry-common.o
  CC      arch/arm/kernel/irq.o
  CC      arch/arm/kernel/opcodes.o
  AS      arch/arm/vfp/vfphw.o
  CC      arch/arm/kernel/process.o
  CC      arch/arm/kernel/ptrace.o
  CC      arch/arm/vfp/vfpsingle.o
  CC      arch/arm/vfp/vfpdouble.o
  LD      arch/arm/common/built-in.o
  CC      init/version.o
  CC      arch/arm/mm/extable.o
  CC      arch/arm/probes/decode.o
  CC      arch/arm/probes/kprobes/core.o
  CC      arch/arm/probes/decode-arm.o
  LD      arch/arm/net/built-in.o
  CC      arch/arm/probes/kprobes/actions-common.o
  CC      arch/arm/probes/kprobes/checkers-common.o
  CC      arch/arm/mm/fault.o
  LD      arch/arm/crypto/built-in.o
  CC      arch/arm/mm/init.o
  CC      arch/arm/kernel/reboot.o
  LD      init/mounts.o
  LD      init/built-in.o
  CC      arch/arm/kernel/return_address.o
  CC      arch/arm/kernel/setup.o
  CC      arch/arm/kernel/signal.o
  LD      arch/arm/firmware/built-in.o
  CC      arch/arm/probes/kprobes/actions-arm.o
  CC      arch/arm/mach-mv78xx0/common.o
  CC      arch/arm/plat-orion/irq.o
  CC      arch/arm/plat-orion/pcie.o
  LD      arch/arm/vfp/vfp.o
  LD      arch/arm/vfp/built-in.o
  CC      arch/arm/probes/kprobes/checkers-arm.o
  AS      arch/arm/kernel/sigreturn_codes.o
  CC      arch/arm/mm/iomap.o
  CC      kernel/fork.o
  CC      kernel/exec_domain.o
  CC      kernel/panic.o
  LD      arch/arm/probes/kprobes/built-in.o
  LD      arch/arm/probes/built-in.o
  CC      kernel/cpu.o
  CC      arch/arm/mm/fault-armv.o
  CC      arch/arm/kernel/stacktrace.o
  CC      arch/arm/mach-mv78xx0/mpp.o
  CC      arch/arm/plat-orion/time.o
  CC      kernel/exit.o
  CC      kernel/softirq.o
  CC      arch/arm/mm/flush.o
  CC      kernel/resource.o
  CC      arch/arm/mm/idmap.o
  CC      arch/arm/mach-mv78xx0/irq.o
  CC      arch/arm/kernel/sys_arm.o
  CC      arch/arm/plat-orion/common.o
  CC      arch/arm/mach-mv78xx0/pcie.o
  CC      arch/arm/plat-orion/mpp.o
  CC      arch/arm/mm/ioremap.o
  CC      arch/arm/kernel/time.o
  CC      kernel/sysctl.o
  CC      arch/arm/mach-mv78xx0/db78x00-bp-setup.o
  CC      arch/arm/kernel/traps.o
  CC      arch/arm/kernel/atags_parse.o
  LD      certs/built-in.o
  AS      arch/arm/kernel/entry-armv.o
  CC      arch/arm/plat-orion/gpio.o
  CC      arch/arm/kernel/armksyms.o
  CC      arch/arm/mm/mmap.o
  CC      mm/filemap.o
  CC      arch/arm/mach-mv78xx0/rd78x00-masa-setup.o
  CC      kernel/sysctl_binary.o
  CC      mm/mempool.o
  CC      mm/oom_kill.o
  CC      arch/arm/mm/pgd.o
  CC      arch/arm/kernel/module.o
  CC      arch/arm/mach-mv78xx0/buffalo-wxl-setup.o
  CC      mm/maccess.o
/home/kisskb/slave/src/mm/filemap.c: In function 'clear_bit_unlock_is_negative_byte':
/home/kisskb/slave/src/mm/filemap.c:933:2: error: too few arguments to function 'test_bit'
/home/kisskb/slave/src/include/asm-generic/bitops/non-atomic.h:103:19: note: declared here
  LD      arch/arm/plat-orion/built-in.o
/home/kisskb/slave/src/mm/filemap.c:934:1: warning: control reaches end of non-void function [-Wreturn-type]
/home/kisskb/slave/src/scripts/Makefile.build:293: recipe for target 'mm/filemap.o' failed
make[2]: *** [mm/filemap.o] Error 1
make[2]: *** Waiting for unfinished jobs....
  CC      ipc/util.o
  CC      fs/open.o
  CC      fs/read_write.o
  CC      arch/arm/kernel/bios32.o
  CC      arch/arm/mm/mmu.o
  CC      kernel/capability.o
  CC      kernel/ptrace.o
  CC      arch/arm/mm/pageattr.o
  LD      arch/arm/mach-mv78xx0/built-in.o
  CC      ipc/msgutil.o
  CC      arch/arm/kernel/isa.o
/home/kisskb/slave/src/Makefile:988: recipe for target 'mm' failed
make[1]: *** [mm] Error 2
make[1]: *** Waiting for unfinished jobs....
  AS      arch/arm/kernel/sleep.o
  CC      arch/arm/kernel/suspend.o
  CC      ipc/msg.o
  CC      arch/arm/kernel/patch.o
  CC      arch/arm/kernel/insn.o
  CC      ipc/sem.o
  CC      ipc/shm.o
  CC      ipc/syscall.o
  CC      arch/arm/mm/proc-syms.o
  CC      arch/arm/mm/alignment.o
  CC      arch/arm/mm/highmem.o
  CC      arch/arm/kernel/unwind.o
  CC      arch/arm/kernel/devtree.o
  CC      kernel/user.o
  CC      ipc/ipc_sysctl.o
  CC      fs/file_table.o
  AS      arch/arm/mm/abort-ev5t.o
  CC      fs/super.o
  CC      kernel/signal.o
  CC      kernel/sys.o
  CC      arch/arm/kernel/perf_regs.o
  AS      arch/arm/mm/pabort-legacy.o
  CC      arch/arm/mm/copypage-feroceon.o
  CC      kernel/kmod.o
  CC      kernel/workqueue.o
  CC      kernel/pid.o
  CC      arch/arm/kernel/perf_callchain.o
  AS      arch/arm/mm/tlb-v4wbi.o
  AS      arch/arm/mm/proc-feroceon.o
  CC      kernel/task_work.o
  CC      arch/arm/mm/l2c-common.o
  LD      ipc/built-in.o
  CC      kernel/extable.o
  CC      arch/arm/mm/cache-feroceon-l2.o
  CC      fs/char_dev.o
  CC      kernel/params.o
  CC      arch/arm/kernel/perf_event_xscale.o
  CC      arch/arm/kernel/perf_event_v6.o
  CC      fs/stat.o
  CC      arch/arm/kernel/perf_event_v7.o
  CC      arch/arm/kernel/io.o
  CC      fs/exec.o
  CC      fs/pipe.o
  AS      arch/arm/kernel/debug.o
  LD      arch/arm/mm/built-in.o
  AS      arch/arm/kernel/head.o
  CC      kernel/kthread.o
  CC      fs/namei.o
  LDS     arch/arm/kernel/vmlinux.lds
  LD      arch/arm/kernel/built-in.o
  CC      fs/fcntl.o
  CC      kernel/sys_ni.o
  CC      kernel/nsproxy.o
  CC      kernel/notifier.o
  CC      kernel/ksysfs.o
  CC      kernel/cred.o
  CC      fs/ioctl.o
  CC      fs/readdir.o
  CC      kernel/reboot.o
  CC      kernel/async.o
  CC      kernel/range.o
  CC      kernel/smpboot.o
  CC      fs/select.o
  CC      fs/dcache.o
  CC      fs/inode.o
  CC      fs/attr.o
  CC      fs/bad_inode.o
  CC      kernel/ucount.o
  CC      kernel/groups.o
  CC      fs/file.o
  CC      kernel/bpf/core.o
  CC      kernel/events/core.o
  CC      fs/filesystems.o
  CC      kernel/irq/irqdesc.o
  CC      kernel/irq/handle.o
  CC      kernel/events/ring_buffer.o
  CC      kernel/events/callchain.o
  CC      kernel/irq/manage.o
  LD      kernel/livepatch/built-in.o
  CC      fs/namespace.o
  CC      kernel/irq/spurious.o
  CC      kernel/locking/mutex.o
  CC      kernel/locking/semaphore.o
  LD      kernel/bpf/built-in.o
  CC      kernel/irq/resend.o
  CC      fs/seq_file.o
  CC      kernel/locking/rwsem.o
  CC      kernel/locking/percpu-rwsem.o
  CC      kernel/locking/rtmutex.o
  CC      fs/xattr.o
  CC      fs/libfs.o
  CC      kernel/irq/chip.o
  CC      fs/fs-writeback.o
  CC      kernel/locking/rwsem-xadd.o
  CC      kernel/irq/dummychip.o
  CC      kernel/power/qos.o
  CC      kernel/power/main.o
  CC      kernel/irq/devres.o
  LD      kernel/locking/built-in.o
  CC      fs/pnode.o
  CC      fs/splice.o
  CC      kernel/irq/generic-chip.o
  CC      kernel/irq/autoprobe.o
  CC      kernel/irq/irqdomain.o
  CC      fs/sync.o
  CC      kernel/irq/proc.o
  CC      kernel/power/process.o
  CC      kernel/power/suspend.o
  CC      kernel/irq/pm.o
  CC      fs/utimes.o
  CC      kernel/printk/printk.o
  CC      kernel/printk/nmi.o
  CC      kernel/power/poweroff.o
  CC      fs/stack.o
  LD      kernel/irq/built-in.o
  CC      kernel/rcu/update.o
  CC      kernel/rcu/sync.o
  LD      kernel/power/built-in.o
  CC      fs/fs_struct.o
  CC      kernel/sched/core.o
  CC      kernel/rcu/srcu.o
  CC      kernel/sched/loadavg.o
  CC      kernel/time/time.o
  CC      kernel/trace/trace_clock.o
  CC      kernel/time/timer.o
  CC      kernel/trace/ring_buffer.o
  CC      kernel/trace/trace.o
  CC      fs/statfs.o
  CC      fs/fs_pin.o
  CC      kernel/rcu/tree.o
/home/kisskb/slave/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/home/kisskb/slave/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
  CC      fs/nsfs.o
  LD      kernel/events/built-in.o
  CC      fs/buffer.o
  CC      kernel/freezer.o
  CC      kernel/sched/clock.o
  CC      kernel/sched/cputime.o
  CC      kernel/time/hrtimer.o
  LD      kernel/printk/built-in.o
  CC      kernel/time/timekeeping.o
  CC      kernel/profile.o
  CC      kernel/time/ntp.o
  CC      fs/block_dev.o
  CC      fs/direct-io.o
  CC      kernel/stacktrace.o
  CC      kernel/futex.o
  CC      kernel/up.o
  CC      fs/mpage.o
  CC      kernel/time/clocksource.o
  CC      kernel/sched/idle_task.o
  LD      kernel/rcu/built-in.o
  CC      fs/proc_namespace.o
  CC      fs/cramfs/inode.o
  CC      kernel/trace/trace_output.o
  CC      kernel/sched/fair.o
  CC      kernel/time/jiffies.o
  CC      kernel/time/timer_list.o
  CC      kernel/time/timeconv.o
  CC      kernel/time/timecounter.o
  CC      kernel/time/alarmtimer.o
  CC      kernel/time/posix-timers.o
  CC      fs/debugfs/inode.o
  CC      kernel/time/posix-cpu-timers.o
  CC      fs/cramfs/uncompress.o
  CC      kernel/trace/trace_seq.o
  LD      fs/cramfs/cramfs.o
  LD      fs/cramfs/built-in.o
  CC      fs/devpts/inode.o
  CC      kernel/sched/rt.o
  CC      kernel/sched/deadline.o
  CC      kernel/trace/trace_stat.o
  CC      fs/debugfs/file.o
  CC      kernel/uid16.o
  CC      kernel/module.o
  CC      kernel/trace/trace_printk.o
  CC      kernel/kallsyms.o
  CC      kernel/time/posix-clock.o
  CC      kernel/trace/trace_sched_switch.o
  LD      fs/devpts/devpts.o
  LD      fs/devpts/built-in.o
  CC      kernel/trace/trace_nop.o
  CC      kernel/sched/stop_task.o
  CC      kernel/trace/blktrace.o
  CC      kernel/kprobes.o
  CC      kernel/sched/wait.o
  CC      kernel/trace/trace_events.o
  CC      kernel/time/itimer.o
  LD      fs/exofs/built-in.o
  CC      kernel/time/clockevents.o
  LD      fs/debugfs/debugfs.o
  LD      fs/debugfs/built-in.o
  CC      kernel/utsname_sysctl.o
  CC      fs/exportfs/expfs.o
  CC      kernel/sched/swait.o
  CC      kernel/trace/trace_export.o
  CC      kernel/tracepoint.o
  LD      fs/exportfs/exportfs.o
  LD      fs/exportfs/built-in.o
  CC      fs/ext2/balloc.o
  CC      kernel/sched/completion.o
  CC      kernel/elfcore.o
  CC      fs/ext2/dir.o
  CC      kernel/time/tick-common.o
  CC      kernel/time/sched_clock.o
  CC      kernel/time/tick-oneshot.o
  CC      kernel/time/tick-sched.o
  CC      kernel/sched/idle.o
  CC      kernel/sched/stats.o
  CC      kernel/sched/debug.o
  CC      kernel/trace/trace_event_perf.o
  CC      fs/ext2/file.o
  CC      fs/ext2/ialloc.o
  CC      kernel/trace/trace_events_filter.o
  CC      kernel/time/timekeeping_debug.o
  CC      kernel/trace/trace_events_trigger.o
  CC      kernel/irq_work.o
  CC      fs/ext2/inode.o
  CC      fs/ext2/ioctl.o
  CC      fs/ext2/namei.o
  CC      kernel/trace/trace_kprobe.o
  CC      kernel/cpu_pm.o
  LD      kernel/time/built-in.o
  CC      kernel/trace/power-traces.o
  LD      kernel/sched/built-in.o
  CC      fs/ext4/balloc.o
  CC      fs/ext4/bitmap.o
  CC      fs/fat/cache.o
  LD      fs/isofs/built-in.o
  CC [M]  fs/isofs/namei.o
  CC      fs/jbd2/transaction.o
  CC      fs/jffs2/compr.o
  CC [M]  fs/isofs/inode.o
  CC      fs/jffs2/dir.o
  CC      fs/fat/dir.o
  CC      fs/ext2/super.o
  CC      fs/jffs2/file.o
  CC      fs/ext2/symlink.o
  CC      kernel/trace/rpm-traces.o
  CC      fs/jffs2/ioctl.o
  CC      fs/ext4/dir.o
  CC      fs/ext4/file.o
  CC      fs/fat/fatent.o
  CC      fs/fat/file.o
  CC      fs/jffs2/nodelist.o
  CC [M]  fs/isofs/dir.o
  CC      kernel/trace/trace_probe.o
  CC      fs/jffs2/malloc.o
  CC      fs/jffs2/read.o
  LD      fs/ext2/ext2.o
  CC      fs/fat/inode.o
  LD      fs/ext2/built-in.o
  CC [M]  fs/isofs/util.o
  CC      fs/jbd2/commit.o
  CC      kernel/membarrier.o
  CC      fs/ext4/fsync.o
  CC      fs/jffs2/nodemgmt.o
  CC      fs/jffs2/readinode.o
  CC      kernel/memremap.o
  CC [M]  fs/isofs/rock.o
  CC [M]  fs/isofs/export.o
  CC [M]  fs/isofs/joliet.o
  LD      kernel/trace/built-in.o
  CC      fs/jffs2/write.o
  CC      fs/fat/misc.o
  LD      kernel/built-in.o
  CC      fs/ext4/ialloc.o
  CC      fs/jbd2/recovery.o
  CC      fs/kernfs/mount.o
  CC      fs/kernfs/inode.o
  CC      fs/kernfs/dir.o
  LD [M]  fs/isofs/isofs.o
  CC      fs/kernfs/file.o
  CC      fs/kernfs/symlink.o
  CC      fs/jbd2/checkpoint.o
  CC      fs/fat/nfs.o
  CC      fs/jbd2/revoke.o
  CC      fs/jffs2/scan.o
  CC      fs/jffs2/gc.o
  CC      fs/jffs2/symlink.o
  CC      fs/fat/namei_vfat.o
  CC      fs/lockd/clntlock.o
  CC      fs/nfs/client.o
  CC      fs/nfs/dir.o
  CC      fs/fat/namei_msdos.o
  LD      fs/kernfs/built-in.o
  CC      fs/nfs_common/grace.o
  CC      fs/jbd2/journal.o
  CC      fs/nls/nls_base.o
  CC      fs/ext4/inode.o
  LD      fs/nfs_common/built-in.o
  CC      fs/ext4/page-io.o
  CC      fs/nls/nls_cp437.o
  CC      fs/nls/nls_cp850.o
  CC      fs/jffs2/build.o
  LD      fs/fat/fat.o
  LD      fs/fat/vfat.o
  LD      fs/fat/msdos.o
  LD      fs/fat/built-in.o
  CC      fs/nls/nls_iso8859-1.o
  CC      fs/ext4/ioctl.o
  CC      fs/nls/nls_iso8859-2.o
  CC      fs/lockd/clntproc.o
  CC      fs/lockd/clntxdr.o
  LD      fs/nls/built-in.o
  CC      fs/lockd/host.o
  CC      fs/jffs2/erase.o
  CC      fs/jffs2/background.o
  CC      fs/nfs/file.o
  CC      fs/lockd/svc.o
  CC      fs/notify/fsnotify.o
  CC      fs/nfs/getroot.o
  CC      fs/jffs2/fs.o
  CC      fs/jffs2/writev.o
  CC      fs/jffs2/super.o
  CC      fs/proc/task_mmu.o
  CC      fs/notify/notification.o
  CC      fs/proc/inode.o
  LD      fs/quota/built-in.o
  CC      fs/proc/root.o
  LD      fs/jbd2/jbd2.o
  LD      fs/jbd2/built-in.o
  CC      fs/proc/base.o
  CC      fs/lockd/svclock.o
  CC      fs/nfs/inode.o
  CC      fs/nfs/super.o
  CC      fs/notify/group.o
  CC      fs/jffs2/debug.o
  CC      fs/nfs/io.o
  CC      fs/proc/generic.o
  CC      fs/nfs/direct.o
  CC      fs/notify/inode_mark.o
  CC      fs/jffs2/wbuf.o
  CC      fs/proc/array.o
  CC      fs/lockd/svcshare.o
  CC      fs/notify/mark.o
  CC      fs/jffs2/compr_rtime.o
  CC      fs/ext4/namei.o
  CC      fs/nfs/pagelist.o
  CC      fs/ext4/super.o
  CC      fs/ext4/symlink.o
  CC      fs/ramfs/inode.o
  CC      fs/jffs2/compr_zlib.o
  CC      fs/notify/vfsmount_mark.o
  CC      fs/proc/fd.o
  CC      fs/sysfs/file.o
  LD      fs/jffs2/jffs2.o
  CC      fs/lockd/svcproc.o
  LD      fs/jffs2/built-in.o
  CC      fs/lockd/svcsubs.o
  CC      fs/tracefs/inode.o
  CC      fs/ramfs/file-mmu.o
  CC      fs/notify/fdinfo.o
  CC      fs/sysfs/dir.o
  CC      fs/proc/proc_tty.o
  LD      fs/ramfs/ramfs.o
  LD      fs/ramfs/built-in.o
  CC      fs/ext4/hash.o
  CC      fs/notify/dnotify/dnotify.o
  CC      fs/nfs/read.o
  LD      fs/tracefs/tracefs.o
  LD      fs/tracefs/built-in.o
  CC      fs/proc/cmdline.o
  CC      fs/lockd/mon.o
  CC      fs/sysfs/symlink.o
  LD      fs/notify/dnotify/built-in.o
  LD      fs/udf/built-in.o
  CC [M]  fs/udf/balloc.o
  LD      fs/notify/fanotify/built-in.o
  CC      fs/notify/inotify/inotify_fsnotify.o
  CC      fs/proc/consoles.o
  CC      fs/lockd/xdr.o
  CC      fs/ext4/resize.o
  CC      fs/proc/cpuinfo.o
  CC      fs/notify/inotify/inotify_user.o
  CC      fs/sysfs/mount.o
  CC      fs/sysfs/group.o
  CC      fs/proc/devices.o
  CC      fs/nfs/symlink.o
  CC [M]  fs/udf/dir.o
  CC      fs/proc/interrupts.o
  CC      fs/proc/loadavg.o
  CC      fs/proc/meminfo.o
  LD      fs/sysfs/built-in.o
  CC      fs/proc/stat.o
  LD      fs/notify/inotify/built-in.o
  LD      fs/notify/built-in.o
  CC      fs/lockd/clnt4xdr.o
  CC      fs/lockd/xdr4.o
  CC      fs/eventpoll.o
  CC      fs/ext4/extents.o
  CC [M]  fs/udf/file.o
  CC [M]  fs/udf/ialloc.o
  CC      fs/proc/uptime.o
  CC      fs/nfs/unlink.o
  CC      fs/nfs/write.o
  CC [M]  fs/udf/inode.o
  CC      fs/proc/version.o
  CC      fs/proc/softirqs.o
  CC      fs/lockd/svc4proc.o
  CC      fs/proc/namespaces.o
  CC      fs/proc/self.o
  CC      fs/proc/thread_self.o
  CC      fs/proc/proc_sysctl.o
  CC      fs/lockd/procfs.o
  CC      fs/proc/proc_net.o
  CC      fs/nfs/namespace.o
  CC      fs/ext4/ext4_jbd2.o
  CC      fs/nfs/mount_clnt.o
  CC [M]  fs/udf/lowlevel.o
  LD      fs/lockd/lockd.o
  LD      fs/lockd/built-in.o
  CC      fs/nfs/nfstrace.o
  CC      fs/nfs/nfsroot.o
  CC [M]  fs/udf/namei.o
  CC      fs/proc/kmsg.o
  CC      fs/nfs/sysctl.o
  CC [M]  fs/udf/partition.o
  CC      fs/proc/page.o
  CC      fs/ext4/migrate.o
  CC      fs/nfs/nfs2super.o
  CC [M]  fs/udf/super.o
  CC [M]  fs/udf/truncate.o
  CC [M]  fs/udf/symlink.o
  LD      fs/proc/proc.o
  LD      fs/proc/built-in.o
  CC      fs/anon_inodes.o
  CC      fs/signalfd.o
  CC      fs/timerfd.o
  CC      fs/ext4/mballoc.o
  CC      fs/eventfd.o
  CC      fs/nfs/proc.o
  CC      fs/nfs/nfs2xdr.o
  CC      fs/nfs/nfs3super.o
  CC      fs/nfs/nfs3client.o
  CC      fs/aio.o
  CC      fs/locks.o
  CC      fs/nfs/nfs3proc.o
  CC [M]  fs/udf/directory.o
  CC [M]  fs/udf/misc.o
  CC      fs/nfs/nfs3xdr.o
  CC [M]  fs/udf/udftime.o
  CC [M]  fs/udf/unicode.o
  CC      fs/binfmt_script.o
  LD      fs/nfs/nfs.o
  CC      fs/binfmt_elf.o
  CC      fs/mbcache.o
  CC      fs/coredump.o
  CC      fs/ext4/block_validity.o
  LD [M]  fs/udf/udf.o
  LD      fs/nfs/nfsv2.o
  CC      fs/ext4/move_extent.o
  CC      fs/drop_caches.o
  CC      fs/ext4/mmp.o
  CC      fs/fhandle.o
  CC      fs/dcookies.o
  CC      fs/ext4/indirect.o
  CC      fs/ext4/extents_status.o
  CC      fs/ext4/xattr.o
  LD      fs/nfs/nfsv3.o
  LD      fs/nfs/built-in.o
  CC      fs/ext4/xattr_user.o
  CC      fs/ext4/xattr_trusted.o
  CC      fs/ext4/inline.o
  CC      fs/ext4/readpage.o
  CC      fs/ext4/sysfs.o
  LD      fs/ext4/ext4.o
  LD      fs/ext4/built-in.o
  LD      fs/built-in.o
make[1]: Leaving directory '/home/kisskb/slave/build/linus_mv78xx0_defconfig_arm'
Makefile:150: recipe for target 'sub-make' failed
make: *** [sub-make] Error 2
Command 'make -j 10 ARCH=arm O=/home/kisskb/slave/build/linus_mv78xx0_defconfig_arm CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-  ' returned non-zero exit status 2
# rm -rf /home/kisskb/slave/build/linus_mv78xx0_defconfig_arm
# Build took: 0:00:40.795119