Commit Graph

515406 Commits

Author SHA1 Message Date
Andrey Ryabinin 6e54abac1b kasan: Makefile: shut up warnings if CONFIG_COMPILE_TEST=y
It might be annoying to constantly see this:

	scripts/Makefile.kasan:16: Cannot use CONFIG_KASAN: -fsanitize=kernel-address is not supported by compiler

while performing allmodconfig/allyesconfig build tests.
Disable this warning if CONFIG_COMPILE_TEST=y.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:59 -04:00
Rasmus Villemoes 6ceafb880c fs/binfmt_misc.c: simplify entry_status()
sprintf() reliably returns the number of characters printed, so we don't
need to ask strlen() where we are.  Also replace calling sprintf("%02x")
in a loop with the much simpler bin2hex().

[akpm@linux-foundation.org: it's odd to include kernel.h after everything else]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:59 -04:00
Joe Perches e0df7e1fae checkpatch: avoid "spaces required around that ':'" false positive
Since commit 1f65f947a6 ("checkpatch: add checks for question mark and
colon spacing") back in 2008, checkpatch has reported false positive for
asm volatile uses of "::" checkpatch thinks colons should always have
spaces around it.

Add an exception for colons with colons on either side for this valid asm
volatile (and c++) use.

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Yehuda Yitschak <yehuday@marvell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:59 -04:00
Joe Perches 323b267faf checkpatch: fix --fix use with a patch of multiple files
If a patch touches multiple files, the --fix and --fix-inplace option
doesn't keep the proper line count and makes the new patch file not able
to be applied via bad offset line numbers when lines are added or deleted
by the --fix option.

Dunno how that extra backslash snuck in there.

Signed-off-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>
2015-04-17 09:03:58 -04:00
Andy Lutomirski e15f431fe2 errno.h: Improve ENOSYS's comment
ENOSYS is the mechanism used by user code to detect whether the running
kernel implements a given system call.  It should not be returned by
anything except an unimplemented system call.

Unfortunately, it is rather frequently used in the kernel to indicate that
various new functions of existing system calls are not implemented.  This
should be discouraged.

Improve the comment in errno.h to help clarify ENOSYS's purpose.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.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>
2015-04-17 09:03:58 -04:00
Andy Lutomirski 91c9afaf97 checkpatch.pl: new instances of ENOSYS are errors
ENOSYS means that a nonexistent system call was called.  We have a
bad habit of using it for things like invalid operations on
otherwise valid syscalls.  We should avoid this in new code.

Pervasive incorrect usage of ENOSYS came up at the kernel summit ABI
review discussion.  Let's see if checkpatch can help.

I'll submit a separate patch for include/uapi/asm-generic/errno.h.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.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>
2015-04-17 09:03:58 -04:00
Joe Perches c17893c740 checkpatch: add a test for const with __read_mostly uses
const objects shouldn't be __read_mostly.  They are read-only.

Marking these objects as __read_mostly causes section conflicts with LTO
linking.

So add a test to try to avoid this issue.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:58 -04:00
Sam Bobroff d7fe8065ad checkpatch: improve operator spacing check
Code such as:
       x = timercmp(&now, &end, <);
Will currently trigger a checkpatch error. e.g.

ERROR: spaces required around that '<'

This is because the "Ignore operators passed as parameters" check looks
only for a comma following the operator.  Improve the check by also
looking for a close parenthesis.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.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>
2015-04-17 09:03:58 -04:00
Joe Perches b598b67060 checkpatch: add 'Prefer ARRAY_SIZE" test
Add a test for sizeof(foo)/sizeof(foo[0]) that could be ARRAY_SIZE(foo).

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:58 -04:00
Joe Perches 6d07d01b62 checkpatch: add uart_ops to normally const structs
Add another struct to the list of normally const struct types

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:58 -04:00
Joe Perches 29a3c46673 checkpatch: add #define foo "string" long line exception
There are #defines with long string constants like:
	#define foo "some really long string > 80 columns"
Add a long line exception for them.

Miscellanea:

Use the $String variable for slightly better readability

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Madalin-Cristian Bucur <madalin.bucur@freescale.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>
2015-04-17 09:03:57 -04:00
Joe Perches 2a076f40d8 checkpatch, SubmittingPatches: suggest line wrapping commit messages at 75 columns
Commit messages lines are sometimes overly long.

Suggest line wrapping at 75 columns so the default git commit log
indentation of 4 plus the commit message text still fits on an 80 column
screen.

Add a checkpatch test for long commit messages lines too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:57 -04:00
Fabian Frederick 0e212e0a72 checkpatch: don't ask for asm/file.h to linux/file.h unconditionally
Currently checkpatch warns when asm/file.h is included and linux/file.h
exists.  That conversion can be made when linux/file.h includes asm/file.h
which is not always the case.(See signal.h)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Andy Whitcroft <apw@canonical.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:57 -04:00
Joe Perches ab7e23f344 checkpatch: add test for repeated const uses
Using 'const <type> const *' is generally meant to be written 'const
<type> * const'.

Add a test for the miswritten form.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:57 -04:00
Joe Perches f34e4a4f97 checkpatch: improve return negative errno check
Add a few conditions to the test to find
	return (ERRNO);

Make the output message a bit less cryptic too.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:57 -04:00
Joe Perches b392c64f59 checkpatch: match more world writable permissions
Currently checkpatch will fuss if one uses world writable settings in
debugfs files and DEVICE_ATTR uses by testing S_IWUGO but not testing
S_IWOTH, S_IRWXUGO or S_IALLUGO.

Extend the check to catch all cases exporting world writable permissions
including octal values.

[akpm@linux-foundation.org: remove stray $]
Signed-off-by: Joe Perches <joe@perches.com>
Original-patch-by: Nicholas Mc Guire <hofrat@osadl.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:57 -04:00
Joe Perches ebfd7d6237 checkpatch: add optional --codespell dictionary to find more typos
If a codespell dictionary exists, use it if desired.  default is off,
maybe it could be turned on later.

codespell's dictionary format allows multiple possible corrections, ignore
that for now and only use the first suggestion.

Also add \b to spelling test so that consecutive misspelled words
are found properly.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:57 -04:00
Jani Nikula b3e9a677fc checkpatch: spell check reudce
References: http://mid.gmane.org/1424977312-24902-1-git-send-email-ville.syrjala@linux.intel.com

Signed-off-by: Jani Nikula <jani.nikula@intel.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>
2015-04-17 09:03:56 -04:00
Joe Perches 66d7a382cb checkpatch: add spell checking of email subject line
Only commit log and patch additions are checked for typos and spelling
errors currently.  Add a check of the email subject line too.

Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Jani Nikula <jani.nikula@linux.intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:56 -04:00
Joe Perches 6ab3a9701e checkpatch: improve "no space is necessary after a cast" test
The "no space is necessary after a cast" sizeof exclusion doesn't work
properly.

The test reports a false positive for code like:

	BUILD_BUG_ON(sizeof(struct batadv_bla_claim_dst) != 6);

Make it work, simplify the exclusions, and add some comments.

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:56 -04:00
Nicolas Iooss d43698e8ab firmware/ihex2fw.c: restore missing default in switch statement
Commit 2473238eac ("ihex: add support for CS:IP/EIP records") removes
the "default:" statement in the switch block, making the "return
usage();" line dead code and ihex2fw silently ignoring unknown options.
Restore this statement.

This bug was found by building with HOSTCC=clang and adding
-Wunreachable-code-return to HOSTCFLAGS.

Fixes: 2473238eac ("ihex: add support for CS:IP/EIP records")
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:56 -04:00
Yury Norov 2afe27c718 lib/bitmap.c: bitmap_[empty,full]: remove code duplication
bitmap_empty() has its own implementation.  But it's clearly as simple as:

	find_first_bit(src, nbits) == nbits

The same is true for 'bitmap_full'.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:56 -04:00
Javi Merino d48502eacd ASoC: pcm512x: use DIV_ROUND_CLOSEST_ULL() from kernel.h
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Peter Rosin <peda@axentia.se>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:56 -04:00
Javi Merino 512eb720c9 media: cxd2820r: use DIV_ROUND_CLOSEST_ULL()
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: Antti Palosaari <crope@iki.fi>
Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:56 -04:00
Javi Merino ee3c86f356 cpuidle: menu: use DIV_ROUND_CLOSEST_ULL()
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:55 -04:00
Javi Merino aa7762010a clk: bcm/kona: use DIV_ROUND_CLOSEST_ULL()
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Alex Elder <elder@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:55 -04:00
Javi Merino f766093ecb kernel.h: implement DIV_ROUND_CLOSEST_ULL
We have grown a number of different implementations of
DIV_ROUND_CLOSEST_ULL throughout the kernel.  Move the i915 one to
kernel.h so that it can be reused.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Reviewed-by: Jeff Epler <jepler@unpythonic.net>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Guenter Roeck <linux@roeck-us.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Alex Elder <elder@linaro.org>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:55 -04:00
Rasmus Villemoes 675cf53c1d lib/vsprintf.c: improve put_dec_trunc8 slightly
I hadn't had enough coffee when I wrote this. Currently, the final
increment of buf depends on the value loaded from the table, and
causes gcc to emit a cmov immediately before the return. It is smarter
to let it depend on r, since the increment can then be computed in
parallel with the final load/store pair. It also shaves 16 bytes of
.text.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tejun Heo <tj@kernel.org>
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>
2015-04-17 09:03:55 -04:00
Bartosz Golaszewski cdb1dc3f1c hwmon: (w83795) use find_closest_descending() in pwm_freq_to_reg()
Replace the loop iterating over pwm_freq_cksel0 with a call to
find_closest_descending().

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:55 -04:00
Bartosz Golaszewski 0f3721c51e hwmon: (lm85) use find_closest() in x_TO_REG() functions
Replace RANGE_TO_REG() and FREQ_TO_REG() implementations with
calls to find_closest().

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:55 -04:00
Bartosz Golaszewski d38df34e3f hwmon: (ina2xx) replace ina226_avg_bits() with find_closest()
Use find_closest() to locate the closest average in ina226_avg_tab.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:54 -04:00
Bartosz Golaszewski f2027543b9 documentation: update CodingStyle on local variables naming in macros
Describe proper naming convention for local variables in macros
resembling functions.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:54 -04:00
Bartosz Golaszewski 95d119528b util_macros.h: add find_closest() macro
This series unduplicates the code used to find the member in an array
closest to 'x'.

The first patch adds a macro implementing the algorithm in two flavors -
for arrays sorted in ascending and descending order.  The second updates
Documentation/CodingStyle on the naming convention for local variables in
macros resembling functions.  Other three patches replace duplicated code
with calls to one of these macros in some hwmon drivers.

This patch (of 5):

Searching for the member of an array closest to 'x' is duplicated in
several places.

Add a new include - util_macros.h - and two macros that implement this
algorithm for arrays sorted both in ascending and descending order.

Uses linear search.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:54 -04:00
Sebastian Ott a7a2c02a40 lib/dma-debug: fix bucket_find_contain()
bucket_find_contain() will search the bucket list for a dma_debug_entry.
When the entry isn't found it needs to search other buckets too, since
only the start address of a dma range is hashed (which might be in a
different bucket).

A copy of the dma_debug_entry is used to get the previous hash bucket
but when its list is searched the original dma_debug_entry is to be used
not its modified copy.

This fixes false "device driver tries to sync DMA memory it has not allocated"
warnings.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:54 -04:00
Rasmus Villemoes 7c43d9a30c lib/vsprintf.c: even faster binary to decimal conversion
The most expensive part of decimal conversion is the divisions by 10
(albeit done using reciprocal multiplication with appropriately chosen
constants).  I decided to see if one could eliminate around half of
these multiplications by emitting two digits at a time, at the cost of a
200 byte lookup table, and it does indeed seem like there is something
to be gained, especially on 64 bits.  Microbenchmarking shows
improvements ranging from -50% (for numbers uniformly distributed in [0,
2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a
more realistic distribution).

On a larger scale, perf shows that top, one of the big consumers of /proc
data, uses 0.5-1.0% fewer cpu cycles.

I had to jump through some hoops to get the 32 bit code to compile and run
on my 64 bit machine, so I'm not sure how relevant these numbers are, but
just for comparison the microbenchmark showed improvements between -30%
and -10%.

The bloat-o-meter costs are around 150 bytes (the generated code is a
little smaller, so it's not the full 200 bytes) on both 32 and 64 bit.
I'm aware that extra cache misses won't show up in a microbenchmark as
used above, but on the other hand decimal conversions often happen in bulk
(for example in the case of top).

I have of course tested that the new code generates the same output as the
old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9
'random' numbers in-between.

Test and verification code on github: https://github.com/Villemoes/dec.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Tested-by: Jeff Epler <jepler@unpythonic.net>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:54 -04:00
Yury Norov 840620a159 lib: rename lib/find_next_bit.c to lib/find_bit.c
This file contains implementation for all find_*_bit{,_le}
So giving it more generic name looks reasonable.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:54 -04:00
Yury Norov 8f6f19dd51 lib: move find_last_bit to lib/find_next_bit.c
Currently all 'find_*_bit' family is located in lib/find_next_bit.c,
except 'find_last_bit', which is in lib/find_last_bit.c. It seems,
there's no major benefit to have it separated.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:54 -04:00
Yury Norov 2c57a0e233 lib: find_*_bit reimplementation
This patchset does rework to find_bit function family to achieve better
performance, and decrease size of text.  All rework is done in patch 1.
Patches 2 and 3 are about code moving and renaming.

It was boot-tested on x86_64 and MIPS (big-endian) machines.
Performance tests were ran on userspace with code like this:

	/* addr[] is filled from /dev/urandom */
	start = clock();
	while (ret < nbits)
		ret = find_next_bit(addr, nbits, ret + 1);

	end = clock();
	printf("%ld\t", (unsigned long) end - start);

On Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz measurements are: (for
find_next_bit, nbits is 8M, for find_first_bit - 80K)

	find_next_bit:		find_first_bit:
	new	current		new	current
	26932	43151		14777	14925
	26947	43182		14521	15423
	26507	43824		15053	14705
	27329	43759		14473	14777
	26895	43367		14847	15023
	26990	43693		15103	15163
	26775	43299		15067	15232
	27282	42752		14544	15121
	27504	43088		14644	14858
	26761	43856		14699	15193
	26692	43075		14781	14681
	27137	42969		14451	15061
	...			...

find_next_bit performance gain is 35-40%;
find_first_bit - no measurable difference.

On ARM machine, there is arch-specific implementation for find_bit.

Thanks a lot to George Spelvin and Rasmus Villemoes for hints and
helpful discussions.

This patch (of 3):

New implementations takes less space in source file (see diffstat) and in
object.  For me it's 710 vs 453 bytes of text.  It also shows better
performance.

find_last_bit description fixed due to obvious typo.

[akpm@linux-foundation.org: include linux/bitmap.h, per Rasmus]
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:53 -04:00
Richard Weinberger 396ada68ac alpha: forward declare struct pt_regs in processor.h
Removal of exec domains uncovered this new warning.  processor.h re-used
struct pt_regs from personality.h which is now gone.

  ./arch/alpha/include/asm/processor.h:47:33: warning: 'struct pt_regs' declared inside parameter list [enabled by default]

Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:03:53 -04:00
Borislav Petkov 18ecb3bfa5 x86/fpu: Load xsave pointer *after* initialization
So I was playing with gdb today and did this simple thing:

	gdb /bin/ls

	...

	(gdb) run

Box exploded with this splat:

	BUG: unable to handle kernel NULL pointer dereference at 00000000000001d0
	IP: [<ffffffff8100fe5a>] xstateregs_get+0x7a/0x120
	[...]

	Call Trace:
	 ptrace_regset
	 ptrace_request
	 ? wait_task_inactive
	 ? preempt_count_sub
	 arch_ptrace
	 ? ptrace_get_task_struct
	 SyS_ptrace
	 system_call_fastpath

... because we do cache &target->thread.fpu.state->xsave into the
local variable xsave but that pointer is NULL at that time and
it gets initialized later, in init_fpu(), see:

	e7f180dcd8 ("x86/fpu: Change xstateregs_get()/set() to use ->xsave.i387 rather than ->fxsave")

The fix is simple: load xsave *after* init_fpu() has run.

Also do the same in xstateregs_set(), as suggested by Oleg Nesterov.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1429209697-5902-1-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 10:15:47 +02:00
Kan Liang 78d504bcd7 perf/x86/intel: Add Broadwell support for the LBR callstack
Same as Haswell, Broadwell also support the LBR callstack.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1427962377-40955-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:59:07 +02:00
Jacob Pan 6455239601 perf/x86/intel/rapl: Fix energy counter measurements but supporing per domain energy units
RAPL energy hardware unit can vary within a single CPU package, e.g.
HSW server DRAM has a fixed energy unit of 15.3 uJ (2^-16) whereas
the unit on other domains can be enumerated from power unit MSR.

There might be other variations in the future, this patch adds
per cpu model quirk to allow special handling of certain cpus.

hw_unit is also removed from per cpu data since it is not per cpu
and the sampling rate for energy counter is typically not high.

Without this patch, DRAM domain on HSW servers will be counted
4x higher than the real energy counter.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1427405325-780-1-git-send-email-jacob.jun.pan@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:58:56 +02:00
Peter Zijlstra 517e6341fa perf/x86/intel: Fix Core2,Atom,NHM,WSM cycles:pp events
Ingo reported that cycles:pp didn't work for him on some machines.

It turns out that in this commit:

  af4bdcf675 perf/x86/intel: Disallow flags for most Core2/Atom/Nehalem/Westmere events

Andi forgot to explicitly allow that event when he
disabled event flags for PEBS on those uarchs.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: af4bdcf675 ("perf/x86/intel: Disallow flags for most Core2/Atom/Nehalem/Westmere events")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:58:47 +02:00
Linus Torvalds 8053871d0f smp: Fix smp_call_function_single_async() locking
The current smp_function_call code suffers a number of problems, most
notably smp_call_function_single_async() is broken.

The problem is that flush_smp_call_function_queue() does csd_unlock()
_after_ calling csd->func(). This means that a caller cannot properly
synchronize the csd usage as it has to.

Change the code to release the csd before calling ->func() for the
async case, and put a WARN_ON_ONCE(csd->flags & CSD_FLAG_LOCK) in
smp_call_function_single_async() to warn us of improper serialization,
because any waiting there can results in deadlocks when called with
IRQs disabled.

Rename the (currently) unused WAIT flag to SYNCHRONOUS and (re)use it
such that we know what to do in flush_smp_call_function_queue().

Rework csd_{,un}lock() to use smp_load_acquire() / smp_store_release()
to avoid some full barriers while more clearly providing lock
semantics.

Finally move the csd maintenance out of generic_exec_single() into its
callers for clearer code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ Added changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rafael David Tinoco <inaddy@ubuntu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/CA+55aFz492bzLFhdbKN-Hygjcreup7CjMEYk3nTSfRWjppz-OA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:57:52 +02:00
Peter Zijlstra c857eb56e6 perf/x86: Fix hw_perf_event::flags collision
Somehow we ended up with overlapping flags when merging the
RDPMC control flag - this is bad, fix it.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:50:43 +02:00
Peter Zijlstra d7bc3197b4 lockdep: Make print_lock() robust against concurrent release
During sysrq's show-held-locks command it is possible that
hlock_class() returns NULL for a given lock. The result is then (after
the warning):

	|BUG: unable to handle kernel NULL pointer dereference at 0000001c
	|IP: [<c1088145>] get_usage_chars+0x5/0x100
	|Call Trace:
	| [<c1088263>] print_lock_name+0x23/0x60
	| [<c1576b57>] print_lock+0x5d/0x7e
	| [<c1088314>] lockdep_print_held_locks+0x74/0xe0
	| [<c1088652>] debug_show_all_locks+0x132/0x1b0
	| [<c1315c48>] sysrq_handle_showlocks+0x8/0x10

This *might* happen because the thread on the other CPU drops the lock
after we are looking ->lockdep_depth and ->held_locks points no longer
to a lock that is held.

The fix here is to simply ignore it and continue.

Reported-by: Andreas Messerschmid <andreas@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:42:14 +02:00
Linus Torvalds 4fc8adcfec Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull third hunk of vfs changes from Al Viro:
 "This contains the ->direct_IO() changes from Omar + saner
  generic_write_checks() + dealing with fcntl()/{read,write}() races
  (mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
  repeatedly looking at ->f_flags, which can be changed by fcntl(2),
  check ->ki_flags - which cannot) + infrastructure bits for dhowells'
  d_inode annotations + Christophs switch of /dev/loop to
  vfs_iter_write()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
  block: loop: switch to VFS ITER_BVEC
  configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
  VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
  VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
  VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
  NFS: Don't use d_inode as a variable name
  VFS: Impose ordering on accesses of d_inode and d_flags
  VFS: Add owner-filesystem positive/negative dentry checks
  nfs: generic_write_checks() shouldn't be done on swapout...
  ocfs2: use __generic_file_write_iter()
  mirror O_APPEND and O_DIRECT into iocb->ki_flags
  switch generic_write_checks() to iocb and iter
  ocfs2: move generic_write_checks() before the alignment checks
  ocfs2_file_write_iter: stop messing with ppos
  udf_file_write_iter: reorder and simplify
  fuse: ->direct_IO() doesn't need generic_write_checks()
  ext4_file_write_iter: move generic_write_checks() up
  xfs_file_aio_write_checks: switch to iocb/iov_iter
  generic_write_checks(): drop isblk argument
  blkdev_write_iter: expand generic_file_checks() call in there
  ...
2015-04-16 23:27:56 -04:00
Linus Torvalds 84588e7a5d Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota and udf updates from Jan Kara:
 "The pull contains quota changes which complete unification of XFS and
  VFS quota interfaces (so tools can use either interface to manipulate
  any filesystem).  There's also a patch to support project quotas in
  VFS quota subsystem from Li Xi.

  Finally there's a bunch of UDF fixes and cleanups and tiny cleanup in
  reiserfs & ext3"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (21 commits)
  udf: Update ctime and mtime when directory is modified
  udf: return correct errno for udf_update_inode()
  ext3: Remove useless condition in if statement.
  vfs: Add general support to enforce project quota limits
  reiserfs: fix __RASSERT format string
  udf: use int for allocated blocks instead of sector_t
  udf: remove redundant buffer_head.h includes
  udf: remove else after return in __load_block_bitmap()
  udf: remove unused variable in udf_table_free_blocks()
  quota: Fix maximum quota limit settings
  quota: reorder flags in quota state
  quota: paranoia: check quota tree root
  quota: optimize i_dquot access
  quota: Hook up Q_XSETQLIM for id 0 to ->set_info
  xfs: Add support for Q_SETINFO
  quota: Make ->set_info use structure with neccesary info to VFS and XFS
  quota: Remove ->get_xstate and ->get_xstatev callbacks
  gfs2: Convert to using ->get_state callback
  xfs: Convert to using ->get_state callback
  quota: Wire up Q_GETXSTATE and Q_GETXSTATV calls to work with ->get_state
  ...
2015-04-16 22:19:33 -04:00
Linus Torvalds a39ef1a7c6 Merge branch 'for-4.1/drivers' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
 "This is the block driver pull request for 4.1.  As with the core bits,
  this is a relatively slow round.  This pull request contains:

   - Various fixes and cleanups for NVMe, from Alexey Khoroshilov, Chong
     Yuan, myself, Keith Busch, and Murali Iyer.

   - Documentation and code cleanups for nbd from Markus Pargmann.

   - Change of brd maintainer to me, from Ross Zwisler.  At least the
     email doesn't bounce anymore then.

   - Two xen-blkback fixes from Tao Chen"

* 'for-4.1/drivers' of git://git.kernel.dk/linux-block: (23 commits)
  NVMe: Meta data handling through submit io ioctl
  NVMe: Add translation for block limits
  NVMe: Remove check for null
  NVMe: Fix error handling of class_create("nvme")
  xen-blkback: define pr_fmt macro to avoid the duplication of DRV_PFX
  xen-blkback: enlarge the array size of blkback name
  nbd: Return error pointer directly
  nbd: Return error code directly
  nbd: Remove fixme that was already fixed
  nbd: Restructure debugging prints
  nbd: Fix device bytesize type
  nbd: Replace kthread_create with kthread_run
  nbd: Remove kernel internal header
  Documentation: nbd: Add list of module parameters
  Documentation: nbd: Reformat to allow more documentation
  NVMe: increase depth of admin queue
  nvme: Fix PRP list calculation for non-4k system page size
  NVMe: Fix blk-mq hot cpu notification
  NVMe: embedded iod mask cleanup
  NVMe: Freeze admin queue on device failure
  ...
2015-04-16 22:05:27 -04:00
Wei Yongjun 44c144f9c8 dm crypt: fix missing error code return from crypt_ctr error path
Fix to return a negative error code from crypt_ctr()'s optional
parameter processing error path.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-16 22:00:50 -04:00