Oleg Nesterov [Fri, 23 Mar 2012 22:02:39 +0000 (15:02 -0700)]
ptrace: the killed tracee should not enter the syscall
Another old/known problem. If the tracee is killed after it reports
syscall_entry, it starts the syscall and debugger can't control this.
This confuses the users and this creates the security problems for
ptrace jailers.
Change tracehook_report_syscall_entry() to return non-zero if killed,
this instructs syscall_trace_enter() to abort the syscall.
Reported-by: Chris Evans <scarybeasts@gmail.com> Tested-by: Indan Zupancic <indan@nul.nu> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Pedro Alves <palves@redhat.com> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Namjae Jeon [Fri, 23 Mar 2012 22:02:39 +0000 (15:02 -0700)]
fat: fix bug in enforcing Long File Name length
Since '*outlen' is initialized to zero, it is currently possible to
create a filename of length (FAT_LFN_LEN + 1) when utf8 is not enabled.
To enforce the FAT_LFN_LEN limit, we must perform one less iteration.
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com> Signed-off-by: Ravishankar N <cyberax82@gmail.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Namjae Jeon [Fri, 23 Mar 2012 22:02:38 +0000 (15:02 -0700)]
fat: clean up xlate_to_uni()
xlate_to_uni() is called by vfat_build_slots() with sbi->nls_io as the
final argument. nls_io can never be null at this point because the
check is already being done in fat_fill_super() wherein the mount fails
if it is null.
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com> Signed-off-by: Ravishankar N <cyberax82@gmail.com> Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wolfram Sang [Fri, 23 Mar 2012 22:02:36 +0000 (15:02 -0700)]
rtc: ds1307: refactor chip_desc table
The chip_desc table is suboptimal. Currently it requires an entry for
every new chip type, even if it is empty. This has already been
forgotten for the ds1388. Refactor the code, so new entries are only
needed, when they chip type really needs a (non-empty) description.
Also make the table visually more appealing.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Cc: Austin Boyle <Austin.Boyle@aviatnet.com> Cc: David Anders <danders.dev@gmail.com> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kevin Liu [Fri, 23 Mar 2012 22:02:36 +0000 (15:02 -0700)]
drivers/rtc/rtc-max8925.c: fix alarm->enabled mistake in max8925_rtc_read_alarm/max8925_rtc_set_alarm
max8925_rtc_read_alarm() should set alrm->enabled based on both
ALARM_IRQ_MASK and ALARM_CTRL setting. max8925_rtc_set_alarm() should
enable/disable alarm according to ALARM_CTRL reg setting.
Signed-off-by: Kevin Liu <kliu5@marvell.com> Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yong Zhang [Fri, 23 Mar 2012 22:02:34 +0000 (15:02 -0700)]
drivers/rtc: remove IRQF_DISABLED
Since commit e58aa3d2d0cc ("genirq: run irq handlers with interrupts
disabled") we run all interrupt handlers with interrupts disabled and we
even check and yell when an interrupt handler returns with interrupts
enabled - see commit b738a50a2026 ("genirq: warn when handler enables
interrupts").
Venu Byravarasu [Fri, 23 Mar 2012 22:02:33 +0000 (15:02 -0700)]
drivers/rtc/rtc-twl.c: enable RTC irrespective of its prior state
As part of probe, before enabling RTC, RTC_CTRL register is read to check
if it is already running. If RTC is used by kernel alone, then this read
is not required. Even if RTC was enabled already by boot loader, setting
STOP_RTC bit again should not harm. Hence removed unwanted read
operation.
Venu Byravarasu [Fri, 23 Mar 2012 22:02:32 +0000 (15:02 -0700)]
drivers/rtc/rtc-twl.c: optimize IRQ bit access
As the TWL RTC driver has a cached copy of enabled RTC interrupt bits in
variable rtc_irq_bits, that can be checked before really setting or
masking any of the interrupt bits.
Viresh Kumar [Fri, 23 Mar 2012 22:02:30 +0000 (15:02 -0700)]
rtc/rtc-spear: call platform_set_drvdata() before registering rtc device
rtc_device_register() calls rtc-spear routines internally. These
routines call dev_get_drvdata() to get struct spear_rtc_config.
Currently, platform_set_drvdata is called after rtc device is
registered. This causes system to crash, as dev_get_drvdata returns
NULL.
For this we need to call platform_set_drvdata() before registering rtc
device. This requires further cleanup, that leads to removal of
dev_set_drvdata on rtc->dev, which was just not required at all.
Also, we change the parameter to request_irq and pass pointer to config
instead of pointer to rtc struct.
Shiraz Hashim [Fri, 23 Mar 2012 22:02:29 +0000 (15:02 -0700)]
rtc/spear: fix for RTC_AIE_ON and RTC_AIE_OFF ioctl errors
Define API for '.alarm_irq_enable' to enable and disable alarm irq. This
is required by the framework else RTC_AIE_ON and RTC_AIE_OFF ioctls
return errors.
Deepak Sikri [Fri, 23 Mar 2012 22:02:29 +0000 (15:02 -0700)]
rtc-spear: fix for balancing the enable_irq_wake in Power Mgmt
Handle the fix for unbalanced irq for the cases when enable_irq_wake
fails, and a warning related to same is displayed on the console. The
workaround is handled at the driver level.
Bernhard Walle [Fri, 23 Mar 2012 22:02:28 +0000 (15:02 -0700)]
init/do_mounts.c: print error code on mount failure
Printing the error code makes it easier to debug the cause of a mount
failure. For example I had the problem that the root file system could
not be mounted read-writeable because my SD card was write-protected.
Without an error code it looks like the SD card was not detected at all.
Signed-off-by: Bernhard Walle <bernhard@bwalle.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diwakar Tundlam [Fri, 23 Mar 2012 22:02:28 +0000 (15:02 -0700)]
init: check printed flag to skip printing message
Otherwise the 'Calibration skipped' message gets printed everytime a CPU
is hotplugged in, cluttering console for systems that frequently hotplug
CPUs.
Signed-off-by: Diwakar Tundlam <dtundlam@nvidia.com> Cc: Phil Carmody <ext-phil.2.carmody@nokia.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Greg KH <greg@kroah.com> Cc: Sameer Nanda <snanda@chromium.org> Cc: Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Steven Rostedt [Fri, 23 Mar 2012 22:02:27 +0000 (15:02 -0700)]
epoll: comment the funky #ifdef
Looking for a bug in -rt, I stumbled across this code here from: commit 2dfa4eeab0fc ("epoll keyed wakeups: teach epoll about hints coming with
the wakeup key"), specifically:
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static inline void ep_wake_up_nested(wait_queue_head_t *wqueue,
unsigned long events, int subclass)
{
unsigned long flags;
You change the function of ep_wake_up_nested() depending on whether
CONFIG_DEBUG_LOCK_ALLOC is set or not. This looks awfully suspicious,
and there's no comment to explain why. I initially thought that this
was trying to fool lockdep, and hiding a real bug.
Investigating it, I found the creation of wake_up_nested() (which no
longer exists) but was created for the sole purpose of epoll and its
strange wake ups, as explained in commit 0ccf831cbee9 ("lockdep:
annotate epoll")
Although the commit message says "annotate epoll" the change log is much
better at explaining what is happening than what is in the actual code.
Thus a comment is really necessary here. And to save the time of other
developers from having to go trudging through the git logs trying to
figure out why this code exists.
I took parts of the change log and placed it into a comment above the
affected code. This will make the description of what is happening more
visible to new developers that have to look at this code for the first
time.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hans Verkuil [Fri, 23 Mar 2012 22:02:27 +0000 (15:02 -0700)]
poll: add poll_requested_events() and poll_does_not_wait() functions
In some cases the poll() implementation in a driver has to do different
things depending on the events the caller wants to poll for. An example
is when a driver needs to start a DMA engine if the caller polls for
POLLIN, but doesn't want to do that if POLLIN is not requested but instead
only POLLOUT or POLLPRI is requested. This is something that can happen
in the video4linux subsystem among others.
Unfortunately, the current epoll/poll/select implementation doesn't
provide that information reliably. The poll_table_struct does have it: it
has a key field with the event mask. But once a poll() call matches one
or more bits of that mask any following poll() calls are passed a NULL
poll_table pointer.
Also, the eventpoll implementation always left the key field at ~0 instead
of using the requested events mask.
This was changed in eventpoll.c so the key field now contains the actual
events that should be polled for as set by the caller.
The solution to the NULL poll_table pointer is to set the qproc field to
NULL in poll_table once poll() matches the events, not the poll_table
pointer itself. That way drivers can obtain the mask through a new
poll_requested_events inline.
The poll_table_struct can still be NULL since some kernel code calls it
internally (netfs_state_poll() in ./drivers/staging/pohmelfs/netfs.h). In
that case poll_requested_events() returns ~0 (i.e. all events).
Very rarely drivers might want to know whether poll_wait will actually
wait. If another earlier file descriptor in the set already matched the
events the caller wanted to wait for, then the kernel will return from the
select() call without waiting. This might be useful information in order
to avoid doing expensive work.
A new helper function poll_does_not_wait() is added that drivers can use
to detect this situation. This is now used in sock_poll_wait() in
include/net/sock.h. This was the only place in the kernel that needed
this information.
Drivers should no longer access any of the poll_table internals, but use
the poll_requested_events() and poll_does_not_wait() access functions
instead. In order to enforce that the poll_table fields are now prepended
with an underscore and a comment was added warning against using them
directly.
This required a change in unix_dgram_poll() in unix/af_unix.c which used
the key field to get the requested events. It's been replaced by a call
to poll_requested_events().
For qproc it was especially important to change its name since the
behavior of that field changes with this patch since this function pointer
can now be NULL when that wasn't possible in the past.
Any driver accessing the qproc or key fields directly will now fail to compile.
Some notes regarding the correctness of this patch: the driver's poll()
function is called with a 'struct poll_table_struct *wait' argument. This
pointer may or may not be NULL, drivers can never rely on it being one or
the other as that depends on whether or not an earlier file descriptor in
the select()'s fdset matched the requested events.
There are only three things a driver can do with the wait argument:
1) obtain the key field:
events = wait ? wait->key : ~0;
This will still work although it should be replaced with the new
poll_requested_events() function (which does exactly the same).
This will now even work better, since wait is no longer set to NULL
unnecessarily.
2) use the qproc callback. This could be deadly since qproc can now be
NULL. Renaming qproc should prevent this from happening. There are no
kernel drivers that actually access this callback directly, BTW.
3) test whether wait == NULL to determine whether poll would return without
waiting. This is no longer sufficient as the correct test is now
wait == NULL || wait->_qproc == NULL.
However, the worst that can happen here is a slight performance hit in
the case where wait != NULL and wait->_qproc == NULL. In that case the
driver will assume that poll_wait() will actually add the fd to the set
of waiting file descriptors. Of course, poll_wait() will not do that
since it tests for wait->_qproc. This will not break anything, though.
There is only one place in the whole kernel where this happens
(sock_poll_wait() in include/net/sock.h) and that code will be replaced
by a call to poll_does_not_wait() in the next patch.
Note that even if wait->_qproc != NULL drivers cannot rely on poll_wait()
actually waiting. The next file descriptor from the set might match the
event mask and thus any possible waits will never happen.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Reviewed-by: Jonathan Corbet <corbet@lwn.net> Reviewed-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Darrick J. Wong [Fri, 23 Mar 2012 22:02:26 +0000 (15:02 -0700)]
crc32: select an algorithm via Kconfig
Allow the kernel builder to choose a crc32* algorithm for the kernel.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Darrick J. Wong [Fri, 23 Mar 2012 22:02:26 +0000 (15:02 -0700)]
crc32: add self-test code for crc32c
Add self-test code for crc32c.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Darrick J. Wong [Fri, 23 Mar 2012 22:02:25 +0000 (15:02 -0700)]
crypto: crc32c should use library implementation
Since lib/crc32.c now provides crc32c, remove the software implementation
here and call the library function instead.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Darrick J. Wong [Fri, 23 Mar 2012 22:02:25 +0000 (15:02 -0700)]
crc32: bolt on crc32c
Reuse the existing crc32 code to stamp out a crc32c implementation.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Bob Pearson <rpearson@systemfabricworks.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:24 +0000 (15:02 -0700)]
crc32: add note about this patchset to crc32.c
Add a comment at the top of crc32.c
[djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:24 +0000 (15:02 -0700)]
crc32: optimize loop counter for x86
Add two changes that improve the performance of x86 systems
1. replace main loop with incrementing counter this change improves
the performance of the selftest by about 5-6% on Nehalem CPUs. The
apparent reason is that the compiler can use the loop index to perform
an indexed memory access. This is reported to make the performance of
PowerPC CPUs to get worse.
2. replace the rem_len loop with incrementing counter this change
improves the performance of the selftest, which has more than the usual
number of occurances, by about 1-2% on x86 CPUs. In actual work loads
the length is most often a multiple of 4 bytes and this code does not
get executed as often if at all. Again this change is reported to make
the performance of PowerPC get worse.
[djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:24 +0000 (15:02 -0700)]
crc32: add slice-by-8 algorithm to existing code
Add slicing-by-8 algorithm to the existing slicing-by-4 algorithm. This
consists of:
- extend largest BITS size from 32 to 64
- extend tables from tab[4][256] to up to tab[8][256]
- Add code for inner loop.
[djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:23 +0000 (15:02 -0700)]
crc32: make CRC_*_BITS definition correspond to actual bit counts
crc32.c provides a choice of one of several algorithms for computing the
LSB and LSB versions of the CRC32 checksum based on the parameters
CRC_LE_BITS and CRC_BE_BITS.
In the original version the values 1, 2, 4 and 8 respectively selected
versions of the alrogithm that computed the crc 1, 2, 4 and 32 bits as a
time.
This patch series adds a new version that computes the CRC 64 bits at a
time. To make things easier to understand the parameter has been
reinterpreted to actually stand for the number of bits processed in each
step of the algorithm so that the old value 8 has been replaced with the
value 32.
This also allows us to add in a widely used crc algorithm that computes
the crc 8 bits at a time called the Sarwate algorithm.
[djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:23 +0000 (15:02 -0700)]
crc32: fix mixing of endian-specific types
crc32.c in its original version freely mixed u32, __le32 and __be32 types
which caused warnings from sparse with __CHECK_ENDIAN__. This patch fixes
these by forcing the types to u32.
[djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:22 +0000 (15:02 -0700)]
crc32: miscellaneous cleanups
Misc cleanup of lib/crc32.c and related files.
- remove unnecessary header files.
- straighten out some convoluted ifdef's
- rewrite some references to 2 dimensional arrays as 1 dimensional
arrays to make them correct. I.e. replace tab[i] with tab[0][i].
- a few trivial whitespace changes
- fix a warning in gen_crc32tables.c caused by a mismatch in the type of
the pointer passed to output table. Since the table is only used at
kernel compile time, it is simpler to make the table big enough to hold
the largest column size used. One cannot make the column size smaller
in output_table because it has to be used by both the le and be tables
and they can have different column sizes.
[djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:22 +0000 (15:02 -0700)]
crc32: simplify unit test code
Replace the unit test provided in crc32.c, which doesn't have a makefile
and doesn't compile with current headers, with a simpler self test
routine that also gives a measure of performance and runs at module init
time. The self test option can be enabled through a configuration
option CONFIG_CRC32_SELFTEST.
The test stresses the pre and post loops and is thus not very realistic
since actual uses will likely have addresses and lengths that are at
least 4 byte aligned. However, the main loop is long enough so that the
performance is dominated by that loop.
The expected values for crc32_le and crc32_be were generated with the
original version of crc32.c using CRC_BITS_LE = 8 and CRC_BITS_BE = 8.
These values were then used to check all the values of the BITS
parameters in both the original and new versions.
The performance results show some variability from run to run in spite
of attempts to both warm the cache and reduce the amount of OS noise by
limiting interrutps during the test. To get comparable results and to
analyse options wrt performance the best time reported over a small
sample of runs has been taken.
[djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:22 +0000 (15:02 -0700)]
crc32: move long comment about crc32 fundamentals to Documentation/
Move a long comment from lib/crc32.c to Documentation/crc32.txt where it
will more likely get read.
Edited the resulting document to add an explanation of the slicing-by-n
algorithm.
[djwong@us.ibm.com: minor changelog tweaks]
[akpm@linux-foundation.org: fix typo, per George] Signed-off-by: George Spelvin <linux@horizon.com> Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bob Pearson [Fri, 23 Mar 2012 22:02:21 +0000 (15:02 -0700)]
crc32: remove two instances of trailing whitespaces
This patchset (re)uses Bob Pearson's crc32 slice-by-8 code to stamp out
a software crc32c implementation. It removes the crc32c implementation
in crypto/ in favor of using the stamped-out one in lib/. There is also
a change to Kconfig so that the kernel builder can pick an
implementation best suited for the hardware.
The motivation for this patchset is that I am working on adding full
metadata checksumming to ext4. As far as performance impact of adding
checksumming goes, I see nearly no change with a standard mail server
ffsb simulation. On a test that involves only file creation and
deletion and extent tree writes, I see a drop of about 50 pcercent with
the current kernel crc32c implementation; this improves to a drop of
about 20 percent with the enclosed crc32c code.
When metadata is usually a small fraction of total IO, this new
implementation doesn't help much because metadata is usually a small
fraction of total IO. However, when we are doing IO that is almost all
metadata (such as rm -rf'ing a tree), then this patch speeds up the
operation substantially.
Incidentally, given that iscsi, sctp, and btrfs also use crc32c, this
patchset should improve their speed as well. I have not yet quantified
that, however. This latest submission combines Bob's patches from late
August 2011 with mine so that they can be one coherent patch set.
Please excuse my inability to combine some of the patches; I've been
advised to leave Bob's patches alone and build atop them instead. :/
Since the last posting, I've also collected some crc32c test results on
a bunch of different x86/powerpc/sparc platforms. The results can be
viewed here: http://goo.gl/sgt3i ; the "crc32-kern-le" and "crc32c"
columns describe the performance of the kernel's current crc32 and
crc32c software implementations. The "crc32c-by8-le" column shows
crc32c performance with this patchset applied. I expect crc32
performance to be roughly the same.
The two _boost columns at the right side of the spreadsheet shows how much
faster the new implementation is over the old one. As you can see, crc32
rises substantially, and crc32c experiences a huge increase.
This patch:
- remove trailing whitespace from lib/crc32.c
- remove trailing whitespace from lib/crc32defs.h
[djwong@us.ibm.com: changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Fri, 23 Mar 2012 22:02:21 +0000 (15:02 -0700)]
checkpatch: check for quoted strings broken across lines
checkpatch already makes an exception to the 80-column rule for quoted
strings, and Documentation/CodingStyle recommends not splitting quoted
strings across lines, because it breaks the ability to grep for the
string. Rather than just permitting this, actively warn about quoted
strings split across lines.
Test case:
void context(void)
{
struct { unsigned magic; const char *strdata; } foo[] = {
{ 42, "these strings"
"do not produce warnings" },
{ 256, "though perhaps"
"they should" },
};
pr_err("this string"
" should produce a warning\n");
pr_err("this multi-line string\n"
"should not produce a warning\n");
asm ("this asm\n\t"
"should not produce a warning");
}
Results of checkpatch on that test case:
WARNING: quoted string split across lines
+ " should produce a warning\n");
total: 0 errors, 1 warnings, 15 lines checked
Signed-off-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Joe Perches <joe@perches.com> Cc: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Fri, 23 Mar 2012 22:02:20 +0000 (15:02 -0700)]
checkpatch: warn on use of yield()
Using yield() is generally wrong. Warn on its use.
Signed-off-by: Joe Perches <joe@perches.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Fri, 23 Mar 2012 22:02:19 +0000 (15:02 -0700)]
checkpatch: add --strict tests for braces, comments and casts
Add some more subjective --strict tests.
Add a test for block comments that start with a blank line followed only
by a line with just the comment block initiator. Prefer a blank line
followed by /* comment...
Add a test for unnecessary spaces after a cast.
Add a test for symmetric uses of braces in if/else blocks.
If one branch needs braces, then all branches should use braces.
Signed-off-by: Joe Perches <joe@perches.com> Cc: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andy Whitcroft [Fri, 23 Mar 2012 22:02:18 +0000 (15:02 -0700)]
checkpatch: high precedence operators do not require additional parentheses in #defines
With any very high precedence operator it is not necessary to enforce
additional parentheses around simple negated expressions. This prevents
us requesting further perentheses around the following:
Andy Whitcroft [Fri, 23 Mar 2012 22:02:18 +0000 (15:02 -0700)]
checkpatch: handle string concatenation in simple #defines
Adjacent strings indicate concatentation, therefore look at identifiers
directly adjacent to literal strings as strings too. This allows us to
better detect the form below and accept it as a simple constant:
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
Signed-off-by: Andy Whitcroft <apw@canonical.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Marek Vasut <marek.vasut@gmail.com> Signed-off-by: Andy Whitcroft <apw@canonical.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xiao Guangrong [Fri, 23 Mar 2012 22:02:15 +0000 (15:02 -0700)]
prio_tree: simplify prio_tree_expand()
In current code, the deleted-node is recorded from first to last,
actually, we can directly attach these node on 'node' we will insert as
the left child, it can let the code more readable.
Akinobu Mita [Fri, 23 Mar 2012 22:02:14 +0000 (15:02 -0700)]
string: memchr_inv() speed improvements
- Generate a 64-bit pattern more efficiently
memchr_inv needs to generate a 64-bit pattern filled with a target
character. The operation can be done by more efficient way.
- Don't call the slow check_bytes() if the memory area is 64-bit aligned
memchr_inv compares contiguous 64-bit words with the 64-bit pattern as
much as possible. The outside of the region is checked by check_bytes()
that scans for each byte. Unfortunately, the first 64-bit word is
unexpectedly scanned by check_bytes() even if the memory area is aligned
to a 64-bit boundary.
Both changes were originally suggested by Eric Dumazet.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Axel Lin <axel.lin@gmail.com> Cc: Peter Meerwald <p.meerwald@bct-electronic.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kim, Milo [Fri, 23 Mar 2012 22:02:13 +0000 (15:02 -0700)]
leds-lm3530: replace pltfm with pdata
Use 'pdata' rather than 'pltfm' in lm3530_init_registers().
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Axel Lin <axel.lin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kim, Milo [Fri, 23 Mar 2012 22:02:12 +0000 (15:02 -0700)]
leds-lm3530: support pwm input mode
* add 'struct lm3530_pwm_data' in the platform data
The pwm data is the platform specific functions which generate the pwm.
The pwm data is only valid when brightness is pwm input mode.
Functions should be implemented by the pwm driver.
pwm_set_intensity() : set duty of pwm.
pwm_get_intensity() : get current the brightness.
* brightness control by pwm
If the control mode is pwm, then brightness is changed by the duty of
pwm=. So pwm platform function should be called in lm3530_brightness_set().
* do not update brightness register when pwm input mode
In pwm input mode, brightness register is not used.
If any value is updated in this register, then the led will be off.
* when input mode is changed, set duty of pwm to 0 if unnecessary.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Brown [Fri, 23 Mar 2012 22:02:11 +0000 (15:02 -0700)]
drivers/leds/leds-gpio.c: use linux/gpio.h rather than asm/gpio.h
Direct usage of the asm include has long been deprecated by the
introduction of gpiolib.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kim, Milo [Fri, 23 Mar 2012 22:02:09 +0000 (15:02 -0700)]
drivers/leds/leds-lp5521.c: redefinition of register bits
For better readability, values of LP5521_REG_ENABLE register were
redefined= . Additional definitions: LP5521_ENABLE_DEFAULT and
LP5521_ENABLE_RUN_PROGRAM= .
Use definition rather than hard code value.
: 0x3F -> 'LP5521_CMD_DIRECT'
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Cc: Arun MURTHY <arun.murthy@stericsson.com> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kim, Milo [Fri, 23 Mar 2012 22:02:09 +0000 (15:02 -0700)]
drivers/leds/leds-lp5521.c: support led pattern data
The lp5521 has autonomous operation mode without external control.
Using lp5521_platform_data, various led patterns can be configurable.
For supporting this feature, new functions and device attribute are
added.
Structure of lp5521_led_pattern: 3 channels are supported - red, green
and blue. Pattern(s) of each channel and numbers of pattern(s) are
defined in the pla= tform data. Pattern data are hexa codes which
include pattern commands such like set pwm, wait, ramp up/down, branch
and so on.
Pattern mode functions:
* lp5521_clear_program_memory
Before running new led pattern, program memory should be cleared.
* lp5521_write_program_memory
Pattern data updated in the program memory via the i2c.
* lp5521_get_pattern
Get pattern from predefined in the platform data.
* lp5521_run_led_pattern
Stop current pattern or run new pattern.
Transition time is required between different operation mode.
Device attribute - 'led_pattern': To load specific led pattern, new device
attribute is added.
When the lp5521 driver is unloaded, stop current led pattern mode.
Documentation updated : description about how to define the led patterns
and example.
Kim, Milo [Fri, 23 Mar 2012 22:02:08 +0000 (15:02 -0700)]
drivers/leds/leds-lp5521.c: add 'update_config' in the lp5521_platform_data
The value of CONFIG register(Addr 08h) is configurable. For supporting
this feature, update_config is added in the platform data. If
'update_config' is not defined, the default value is 'LP5521_PWRSAVE_EN |
LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT'.
To define CONFIG register in the platform data, the bit definitions were
mo= ved to the header file.
Documentation updated : description about 'update_config' and example.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Cc: Arun MURTHY <arun.murthy@stericsson.com> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Carpenter [Fri, 23 Mar 2012 22:02:07 +0000 (15:02 -0700)]
drivers/leds/leds-tca6507.c: cleanup error handling in tca6507_probe()
Just a small tidy-up.
1) There is a NULL dereference if the tca allocation fails.
2) The call to cancel_work_sync() isn't needed because we haven't
scheduled any work.
3) The call to i2c_set_clientdata() isn't needed because the core
handles that automatically if probe() fails.
4) I added some curly braces for style reasons.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Richard Purdie <rpurdie@rpsys.net> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Fri, 23 Mar 2012 22:02:04 +0000 (15:02 -0700)]
bitops: introduce for_each_clear_bit()
Introduce for_each_clear_bit() and for_each_clear_bit_from(). They are
similar to for_each_set_bit() and list_for_each_set_bit_from(), but they
iterate over all the cleared bits in a memory region.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Stefano Panella <stefano.panella@csr.com> Cc: David Vrabel <david.vrabel@csr.com> Cc: Sergei Shtylyov <sshtylyov@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Fri, 23 Mar 2012 22:02:04 +0000 (15:02 -0700)]
bitops: remove for_each_set_bit_cont()
Remove for_each_set_bit_cont() after confirming that no one uses
for_each_set_bit_cont() anymore.
[sfr@canb.auug.org.au: regmap: cope with bitops API change] Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Robert Richter <robert.richter@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Fri, 23 Mar 2012 22:02:03 +0000 (15:02 -0700)]
bitops: rename for_each_set_bit_cont() in favor of analogous list.h function
This renames for_each_set_bit_cont() to for_each_set_bit_from() because
it is analogous to list_for_each_entry_from() in list.h rather than
list_for_each_entry_continue().
This doesn't remove for_each_set_bit_cont() for now.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Randy Dunlap [Fri, 23 Mar 2012 22:02:03 +0000 (15:02 -0700)]
backlight: fix ot200_bl build
Fix build error when GPIO_CS5535 is not enabled:
drivers/built-in.o: In function `ot200_backlight_probe':
ot200_bl.c:(.text+0x205bf): undefined reference to `cs5535_gpio_set'
ot200_bl.c:(.text+0x205d1): undefined reference to `cs5535_gpio_set'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Christian Gmeiner <christian.gmeiner@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for pandora (openpandora.org) backlight.
It might look like all this could be done using pwm_bl.c instead, but
there is a need of special programming sequence when turning on the LED
driver chip or else it will misbehave. Doing this using pwm_bl.c would
require to use some register programming and pwm functions from platform
code, and ARM maintainers are allergic to driver-like code in /arch/arm
nowadays. The PMIC PWM driver is currently missing too, so pwm_bl.c
can't be used anyway.
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kim, Milo [Fri, 23 Mar 2012 22:02:01 +0000 (15:02 -0700)]
backlight: new backlight driver for LP855x devices
THis driver supports TI LP8550/LP8551/LP8552/LP8553/LP8556 backlight
devices.
The brightness can be controlled by the I2C or PWM input. The lp855x
driver provides both modes. For the PWM control, pwm-specific functions
can be defined in the platform data. And some information can be read
via the sysfs(lp855x device attributes).
For details, please refer to Documentation/backlight/lp855x-driver.txt.
[axel.lin@gmail.com: add missing mutex_unlock in lp855x_read_byte() error path]
[axel.lin@gmail.com: check platform data in lp855x_probe()]
[axel.lin@gmail.com: small cleanups]
[dan.carpenter@oracle.com: silence a compiler warning]
[axel.lin@gmail.com: use id->driver_data to differentiate lp855x chips]
[akpm@linux-foundation.org: simplify boolean return expression] Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Julia Lawall [Fri, 23 Mar 2012 22:02:01 +0000 (15:02 -0700)]
drivers/video/backlight/adp5520_bl.c: use devm_ functions
The various devm_ functions allocate memory that is released when a driver
detaches. This patch uses these functions for data that is allocated in
the probe function of a platform device and is only freed in the remove
function.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Julia Lawall [Fri, 23 Mar 2012 22:02:00 +0000 (15:02 -0700)]
drivers/video/backlight: use devm_ functions
The various devm_ functions allocate memory that is released when a driver
detaches. This patch uses these functions for data that is allocated in
the probe function of a platform device and is only freed in the remove
function.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Julia Lawall [Fri, 23 Mar 2012 22:02:00 +0000 (15:02 -0700)]
drivers/video/backlight/wm831x_bl.c: use devm_ functions
The various devm_ functions allocate memory that is released when a driver
detaches. This patch uses these functions for data that is allocated in
the probe function of a platform device and is only freed in the remove
function.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Axel Lin [Fri, 23 Mar 2012 22:01:59 +0000 (15:01 -0700)]
backlight: convert backlight i2c drivers to module_i2c_driver
Factor out some boilerplate code for i2c driver registration into
module_i2c_driver.
Signed-off-by: Axel Lin <axel.lin@gmail.com> Cc: Michael Hennerich <hennerich@blackfin.uclinux.org> Cc: Dmitry Baryshkov <dbaryshkov@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Fri, 23 Mar 2012 22:01:58 +0000 (15:01 -0700)]
MAINTAINERS: add "S: Maintained" to clkdev and clk sections
Russell King seems to be maintaining these. Might as well mark them with
the appropriate S: entry
Signed-off-by: Joe Perches <joe@perches.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / mirror_ubuntu-kernels.git / log