Test: s3cfb_main: send the current timestamp
ashmem: avoid deadlock between read and mmap calls

Avoid holding ashmem_mutex across code that can page fault.  Page faults
grab the mmap_sem for the process, which are also held by mmap calls
prior to calling ashmem_mmap, which locks ashmem_mutex.  The reversed
order of locking between the two can deadlock.

The calls that can page fault are read() and the ASHMEM_SET_NAME and
ASHMEM_GET_NAME ioctls.  Move the code that accesses userspace pages
outside the ashmem_mutex.

Bug: 9261835
Change-Id: If1322e981d29c889a56cdc9dfcbc6df2729a45e9
Signed-off-by: Todd Poynor <toddpoynor@google.com>
lib/memcopy: use glibc version

the kernel's memcpy and memmove is very inefficient. But the glibc version is
quite fast, in some cases it is 10 times faster than the kernel version. So I
introduce some memory copy macros and functions of the glibc to improve the
kernel version's performance.

The strategy of the memory functions is:
1. Copy bytes until the destination pointer is aligned.
2. Copy words in unrolled loops.  If the source and destination are not
   aligned in the same way, use word memory operations, but shift and merge
   two read words before writing.
3. Copy the few remaining bytes.

Signed-off-by: Miao Xie <miaox*******>
Remove ARM sha1 routines

Since commit 8827a4a6b397b07a341ba7fd36ffb91a7835207d
("lib/sha1: use the git implementation of SHA-1"), the ARM SHA1
routines no longer work. The reason? They depended on the larger
320-byte workspace, and now the sha1 workspace is just 16 words
(64 bytes). So the assembly version would overwrite the stack randomly.

The optimized asm version is also probably slower than the new improved
C version, so there's no reason to keep it around.  At least that was
the case in git, where what appears to be the same assembly language
version was removed two years ago because the optimized C BLK_SHA1 code
was faster.

Reported-and-tested-by: Joachim Eastwood <manabian@gmail.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
lib/sha1: use the git implementation of SHA-1

For ChromiumOS, we use SHA-1 to verify the integrity of the root
filesystem. The speed of the kernel sha-1 implementation has a major
impact on our boot performance.

To improve boot performance, we investigated using the heavily
optimized sha-1 implementation used in git. With the git
sha-1 implementation, we see a 11.7% improvement in boot time.

10 reboots, remove slowest/fastest.

Before:

Mean: 6.58 seconds Stdev: 0.14

After (with git sha-1, this patch):

Mean: 5.89 seconds Stdev: 0.07

The other cool thing about the git SHA-1 implementation is that
it only needs 64 bytes of stack for the workspace while the original
kernel implementation needed 320 bytes.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
CC: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
CC: Nicolas Pitre <nico@cam.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: David S. Miller <davem@davemloft.net>
CC: linux-crypto@vger.kernel.org
 mm: change initial readahead window size calculation

Change the logic which determines the initial readahead window size
such that for small requests (one page) the initial window size
will be x4 the size of the original request, regardless of the
VM_MAX_READAHEAD value. This prevents a rapid ramp-up
that could be caused due to increasing VM_MAX_READAHEAD.

Change-Id: I93d59c515d7e6c6d62348790980ff7bd4f434997
Signed-off-by: Lee Susman <lsusman@codeaurora.org>
ARM: 7746/1: mm: lazy cache flushing on non-mapped pages
 ARM: implement optimized percpu variable access

From: Rob Herring <rob.herring@calxeda.com>
 ARM: keep __my_cpu_offset consistent with generic one

Commit 14318ef(ARM: 7587/1: implement optimized percpu variable access)
introduces arm's __my_cpu_offset to optimize percpu vaiable access,
which really works well on hackbench, but will cause __my_cpu_offset
to return garbage value before it is initialized in cpu_init() called
by setup_arch, so accessing percpu variable before setup_arch may cause
kernel hang. But generic __my_cpu_offset always returns zero before
percpu area is brought up, and won't hang kernel.
ext4: Speed up FITRIM by recording flags in ext4_group_info
sync: don't block the flusher thread waiting on IO
timekeeping: fix 32-bit overflow in get_monotonic_boottime
lib/string: use glibc version
Test: blkdev: default BLKDEV_MAX_RQ to 256