There is a helpful comment in do_exit() that states we sync the mm's RSS
info before statistics gathering.

The function that does the statistics gathering is called right above that
comment.

Change the code to obey the comment.
Signed-off-by: NRik van Riel <riel@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This allows detecting improper format string at build time, like:

  fs/coredump.c:225:5: warning: format '%ld' expects argument of type 'long int', but argument 3 has type 'int' [-Wformat=]
       err = cn_printf(cn, "%ld", cprm->siginfo->si_signo);
       ^

As si_signo is always an int, the format should be %d here.
Signed-off-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When adding __printf attribute to cn_printf, gcc reports some issues:

  fs/coredump.c:213:5: warning: format '%d' expects argument of type
  'int', but argument 3 has type 'kuid_t' [-Wformat=]
       err = cn_printf(cn, "%d", cred->uid);
       ^
  fs/coredump.c:217:5: warning: format '%d' expects argument of type
  'int', but argument 3 has type 'kgid_t' [-Wformat=]
       err = cn_printf(cn, "%d", cred->gid);
       ^

These warnings come from the fact that the value of uid/gid needs to be
extracted from the kuid_t/kgid_t structure before being used as an
integer.  More precisely, cred->uid and cred->gid need to be converted to
either user-namespace uid/gid or to init_user_ns uid/gid.

Use init_user_ns in order not to break existing ABI, and document this in
Documentation/sysctl/kernel.txt.

While at it, format uid and gid values with %u instead of %d because
uid_t/__kernel_uid32_t and gid_t/__kernel_gid32_t are unsigned int.
Signed-off-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kmem_cache_alloc() returns void*.
Signed-off-by: NFiro Yang <firogm@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The "fh_len" passed to ->fh_to_* is not guaranteed to be that same as that
returned by encode_fh - it may be larger.

With NFSv2, the filehandle is fixed length, so it may appear longer than
expected and be zero-padded.

So we must test that fh_len is at least some value, not exactly equal to
it.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

bh, od_sup and this_node are unconditionally initialized in
befs_bt_read_super() and befs_btree_find()
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kmem_cache_alloc() returns void*.
Signed-off-by: NFiro Yang <firogm@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If create_dev() function fails to create the root mount device
(/dev/root), then it goes to panic as root device not found but there is
no printk in this case.  So I have added the log in case it fails to
create the root device.  It will help in debugging.

[akpm@linux-foundation.org: simplify printk(), use pr_emerg(), display errno]
Signed-off-by: NVishnu Pratap Singh <vishnu.ps@samsung.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Dan Ehrenberg <dehrenberg@chromium.org>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove duplicate definition of the macro KASAN_FREE_PAGE in
mm/kasan/kasan.h
Signed-off-by: NWang Long <long.wanglong@huawei.com>
Acked-by: NAndrey Ryabinin <a.ryabinin@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kmem_cache_alloc() returns void*.
Signed-off-by: NFiro Yang <firogm@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make this message similar to the "false positives" message and emit it
only once when scanning multiple files instead of after each file scanned.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

People often put diff snippets in changelogs.  This causes problems
when one tries to apply a file containing both the changelog and the
diff because patch(1) tries to apply the diff which it found in the
changelog.

Warn once when what seems to be a diff snippet in the changelog exists.
Signed-off-by: NJoe Perches <joe@perches.com>
Suggested-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is a well defined list of expected values for MODULE_LICENSE so warn
the user upon usage of unknown values.
Signed-off-by: NBjorn Andersson <bjorn.andersson@sonymobile.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Handle multi-line memcpy() properly.
Signed-off-by: NMateusz Kulikowski <mateusz.kulikowski@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Suggest using eth_zero_addr() or eth_broadcast_addr() instead of memset().
Signed-off-by: NMateusz Kulikowski <mateusz.kulikowski@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove 's' modifier to avoid reporting the same warning several times.
Signed-off-by: NMateusz Kulikowski <mateusz.kulikowski@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Check if memcmp() is used to compare ethernet addresses and suggest using
ether_addr_equal() or ether_addr_equal_unaligned()
Signed-off-by: NMateusz Kulikowski <mateusz.kulikowski@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make an exception for the "Does not appear to be a unified-diff" error
when scanning what appears to be git generated cover letters.
Signed-off-by: NJoe Perches <joe@perches.com>
Suggested-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

local is typically used for manually installed apps.
For apps installed from distro the right path is /usr/share.
Signed-off-by: NMaxim Uvarov <maxim.uvarov@linaro.org>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using "git diff | ./scripts/checkpatch -" does not have an
easy mechanism to see the files and lines actually modified.

Add --showfile to see the file and line specified in the diff.

When --showfile is used without --terse, the second line of each
message output is redundant, so it is removed.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add optional colors to make seeing message types a bit easier.

Add --color command line switch, default:on

Error is RED, warning is YELLOW, check is GREEN.  The message type, if
shown, is BLUE.
Signed-off-by: NJoe Perches <joe@perches.com>
Tested-by: NPetr Mladek <pmladek@suse.cz>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If there are multiple patches/files on the command line,
use a prefix before the patch/file message output like:
        --------------
        patch/filename
        --------------
to make the identifying which messages go with which
file/patch a bit easier to parse.

Move the perl version and false positive messages after
all the files have been scanned so that they are emitted
only once.

Standardize the NOTE: <...> form to always emit a blank
line before the NOTE and always use print << "EOM" style.
Signed-off-by: NJoe Perches <joe@perches.com>
Suggested-by: NPetr Mladek <pmladek@suse.cz>
Tested-by: NPetr Mladek <pmladek@suse.cz>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Many lines of code extend beyond the maximum line length.  Some of these
are possibly justified by use type.

For instance:

structure definitions where comments are added per member like:
struct foo {
	type member;		/* some long description */

And lines that don't fit the typical logging message style
where a string constant is used like:

        SOME_MACRO(args, "Some long string");

Categorize these long line types so that checkpatch can use a command-line
--ignore=<type> option to avoid emitting some long line warnings.

One of the existing checkpatch exclusions allowed kernel-doc argument
documentation to exceed 80 columns because old versions of kernel-doc
required single line documentation.  The requirement was removed in 2009
so remove that exclusion.

Add documentation to make the test a bit clearer.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Michael Shuey <shuey@purdue.edu>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

String detection where a source line with a string constant is converted
can either have an X or a space.

Some of the string detection regexes do not allow the space character, but
there is a handy $String variable that does.

Convert the remaining uses of string detection regexes to use the $String
variable to reduce possible false negatives.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

checkpatch uses various cues in its input patches and files to discover
the names of user-defined types and modifiers.  It then uses that
information when processing expressions to discover potential style
issues.

Unfortunately, in rare cases, this means that checkpatch may give
different results if you run it on several input files in one execution,
or one by one!

The reason is that it may identify a type (or something that looks like a
type) in one file, and then carry this information over when processing a
different file.

For example, drivers/staging/media/bcm2048/radio-bcm2048.c contains this
line (in a macro):

	size value;

and drivers/staging/media/davinci_vpfe/vpfe_video.c has this line:

	while (size * *nbuffers > vpfe_dev->video_limit)

If checkpatch processes these 2 files in a single command like:
	./scripts/checkpatch.pl -f $file1 $file2
the (spurious) "size" type detected in the first file will cause it to flag
the second file for improper use of the pointer dereference operator.

To fix this, store types and modifiers found in a file in separate arrays
from built-in ones, and reset the arrays of types and modifiers found in
files at the beginning of each new source file.
Signed-off-by: NAlex Dowad <alexinbeijing@gmail.com>
Signed-off-by: NJoe Perches <joe@perches.com>
Acked-by: NAndy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using declarations like u_int16_t in kernel code is not preferred.

Suggest the kernel sized types instead of the c99 types when not in the
uapi directory.

Add a $typeC99Typedefs variable for the types to check and neaten the
other typedef variables.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Linus sayeth:

: Pretty much every single time people use this "if
: (waitqueue_active())" model, it tends to be a bug, because it means
: that there is zero serialization with people who are just about to go
: to sleep. It's fundamentally racy against all the "wait_event()" loops
: that carefully do memory barriers between testing conditions and going
: to sleep, because the memory barriers now don't exist on the waking
: side.
:
: So I'm making a new rule: if you use waitqueue_active(), I want an
: explanation for why it's not racy with the waiter. A big comment about
: the memory ordering, or about higher-level locks that are held by the
: caller, or something.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc format validation to be able to use kernel-doc script for
checking it.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Reviewed-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This makes a very large function a little smaller.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In one case, we eliminate a local variable; in the other a strlen()
call and some .text.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There's no point in starting over when we meet a '/'.  This also
eliminates a stack variable and a little .text.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This eliminates a little .text and avoids repeating the strchr call when
we meet a '!' (which will happen at least once).
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There's probably not many slashes in the name, but starting over when
we see one feels wrong.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Part of the disassembly of do_blk_trace_setup:

    231b:       e8 00 00 00 00          callq  2320 <do_blk_trace_setup+0x50>
                        231c: R_X86_64_PC32     strlen+0xfffffffffffffffc
    2320:       eb 0a                   jmp    232c <do_blk_trace_setup+0x5c>
    2322:       66 0f 1f 44 00 00       nopw   0x0(%rax,%rax,1)
    2328:       48 83 c3 01             add    $0x1,%rbx
    232c:       48 39 d8                cmp    %rbx,%rax
    232f:       76 47                   jbe    2378 <do_blk_trace_setup+0xa8>
    2331:       41 80 3c 1c 2f          cmpb   $0x2f,(%r12,%rbx,1)
    2336:       75 f0                   jne    2328 <do_blk_trace_setup+0x58>
    2338:       41 c6 04 1c 5f          movb   $0x5f,(%r12,%rbx,1)
    233d:       4c 89 e7                mov    %r12,%rdi
    2340:       e8 00 00 00 00          callq  2345 <do_blk_trace_setup+0x75>
                        2341: R_X86_64_PC32     strlen+0xfffffffffffffffc
    2345:       eb e1                   jmp    2328 <do_blk_trace_setup+0x58>

Yep, that's right: gcc isn't smart enough to realize that replacing '/' by
'_' cannot change the strlen(), so we call it again and again (at least
when a '/' is found).  Even if gcc were that smart, this construction
would still loop over the string twice, once for the initial strlen() call
and then the open-coded loop.

Let's simply use strreplace() instead.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Liked-by: NJens Axboe <axboe@fb.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There's no point in starting over every time we see a ','...
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Strings are sometimes sanitized by replacing a certain character (often
'/') by another (often '!').  In a few places, this is done the same way
Schlemiel the Painter would do it.  Others are slightly smarter but still
do multiple strchr() calls.  Introduce strreplace() to do this using a
single function call and a single pass over the string.

One would expect the return value to be one of three things: void, s, or
the number of replacements made.  I chose the fourth, returning a pointer
to the end of the string.  This is more likely to be useful (for example
allowing the caller to avoid a strlen call).
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently we use per-cpu array to hold pointers to preallocated nodes.
Let's replace it with linked list.  On x86_64 it saves 256 bytes in
per-cpu ELF section which may translate into freeing up 2MB of memory for
NR_CPUS==8192.

[akpm@linux-foundation.org: fix comment, coding style]
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

bitmap_print_to_pagebuf uses scnprintf to copy the cpumask/list to page
buffer.  It handles the newline and trailing null character explicitly.

It's unnecessary and also partially duplicated as scnprintf already adds
trailing null character.  The newline can be passed through format
string to scnprintf.  This patch does that simplification.

However theoretically there's one behavior difference: when the buffer
is too small, the original code would still output '\n' at the end while
the new code(with this patch) would just continue to print the formatted
string.  Since this function is dealing with only page buffers, it's
highly unlikely to hit that corner case.

This patch will help in auditing the users of bitmap_print_to_pagebuf to
verify that the buffer passed is large enough and get rid of it
completely by replacing them with direct scnprintf()

[akpm@linux-foundation.org: tweak comment]
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Suggested-by: NPawel Moll <Pawel.Moll@arm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In case the call side is not providing a swap function, we either use a
32 bit or a generic swap function.  When swapping around pointers on 64
bit architectures falling back to use the generic swap function seems
like an unnecessary waste.

There at least 9 users ('sort' is of difficult to grep for) of sort()
and all of them use the sort function without a customized swap
function.  Furthermore, they are all using pointers to swap around:

arch/x86/kernel/e820.c:sanitize_e820_map()
arch/x86/mm/extable.c:sort_extable()
drivers/acpi/fan.c:acpi_fan_get_fps()
fs/btrfs/super.c:btrfs_descending_sort_devices()
fs/xfs/libxfs/xfs_dir2_block.c:xfs_dir2_sf_to_block()
kernel/range.c:clean_sort_range()
mm/memcontrol.c:__mem_cgroup_usage_register_event()
sound/pci/hda/hda_auto_parser.c:snd_hda_parse_pin_defcfg()
sound/pci/hda/hda_auto_parser.c:sort_pins_by_sequence()

Obviously, we could improve the swap for other sizes as well
but this is overkill at this point.

A simple test shows sorting a 400 element array (try to stay in one
page) with either with u32_swap() or u64_swap() show that the theory
actually works. This test was done on a x86_64 (Intel Xeon E5-4610)
machine.

- swap_32:

NumSamples = 100; Min = 48.00; Max = 49.00
Mean = 48.320000; Variance = 0.217600; SD = 0.466476; Median 48.000000
each * represents a count of 1
   48.0000 -    48.1000 [    68]: ********************************************************************
   48.1000 -    48.2000 [     0]:
   48.2000 -    48.3000 [     0]:
   48.3000 -    48.4000 [     0]:
   48.4000 -    48.5000 [     0]:
   48.5000 -    48.6000 [     0]:
   48.6000 -    48.7000 [     0]:
   48.7000 -    48.8000 [     0]:
   48.8000 -    48.9000 [     0]:
   48.9000 -    49.0000 [    32]: ********************************

- swap_64:

NumSamples = 100; Min = 44.00; Max = 63.00
Mean = 48.250000; Variance = 18.687500; SD = 4.322904; Median 47.000000
each * represents a count of 1
   44.0000 -    45.9000 [    15]: ***************
   45.9000 -    47.8000 [    37]: *************************************
   47.8000 -    49.7000 [    39]: ***************************************
   49.7000 -    51.6000 [     0]:
   51.6000 -    53.5000 [     0]:
   53.5000 -    55.4000 [     0]:
   55.4000 -    57.3000 [     0]:
   57.3000 -    59.2000 [     1]: *
   59.2000 -    61.1000 [     3]: ***
   61.1000 -    63.0000 [     5]: *****

- swap_72:

NumSamples = 100; Min = 53.00; Max = 71.00
Mean = 55.070000; Variance = 21.565100; SD = 4.643824; Median 53.000000
each * represents a count of 1
   53.0000 -    54.8000 [    73]: *************************************************************************
   54.8000 -    56.6000 [     9]: *********
   56.6000 -    58.4000 [     9]: *********
   58.4000 -    60.2000 [     0]:
   60.2000 -    62.0000 [     0]:
   62.0000 -    63.8000 [     0]:
   63.8000 -    65.6000 [     0]:
   65.6000 -    67.4000 [     1]: *
   67.4000 -    69.2000 [     4]: ****
   69.2000 -    71.0000 [     4]: ****

- test program:

static int cmp_32(const void *a, const void *b)
{
	u32 l = *(u32 *)a;
	u32 r = *(u32 *)b;

	if (l < r)
		return -1;
	if (l > r)
		return 1;
	return 0;
}

static int cmp_64(const void *a, const void *b)
{
	u64 l = *(u64 *)a;
	u64 r = *(u64 *)b;

	if (l < r)
		return -1;
	if (l > r)
		return 1;
	return 0;
}

static int cmp_72(const void *a, const void *b)
{
	u32 l = get_unaligned((u32 *) a);
	u32 r = get_unaligned((u32 *) b);

	if (l < r)
		return -1;
	if (l > r)
		return 1;
	return 0;
}

static void init_array32(void *array)
{
	u32 *a = array;
	int i;

	a[0] = 3821;
	for (i = 1; i < ARRAY_ELEMENTS; i++)
		a[i] = next_pseudo_random32(a[i-1]);
}

static void init_array64(void *array)
{
	u64 *a = array;
	int i;

	a[0] = 3821;
	for (i = 1; i < ARRAY_ELEMENTS; i++)
		a[i] = next_pseudo_random32(a[i-1]);
}

static void init_array72(void *array)
{
	char *p;
	u32 v;
	int i;

	v = 3821;
	for (i = 0; i < ARRAY_ELEMENTS; i++) {
		p = (char *)array + (i * 9);
		put_unaligned(v, (u32*) p);
		v = next_pseudo_random32(v);
	}
}

static void sort_test(void (*init)(void *array),
		      int (*cmp) (const void *, const void *),
		      void *array, size_t size)
{
	ktime_t start, stop;
	int i;

	for (i = 0; i < 10000; i++) {
		init(array);

		local_irq_disable();
		start = ktime_get();

		sort(array, ARRAY_ELEMENTS, size, cmp, NULL);

		stop = ktime_get();
		local_irq_enable();

		if (i > 10000 - 101)
		  pr_info("%lld\n",  ktime_to_us(ktime_sub(stop, start)));
	}
}

static void *create_array(size_t size)
{
	void *array;

	array = kmalloc(ARRAY_ELEMENTS * size, GFP_KERNEL);
	if (!array)
		return NULL;

	return array;
}

static int perform_test(size_t size)
{
	void *array;

	array = create_array(size);
	if (!array)
		return -ENOMEM;

	pr_info("test element size %d bytes\n", (int)size);
	switch (size) {
	case 4:
		sort_test(init_array32, cmp_32, array, size);
		break;
	case 8:
		sort_test(init_array64, cmp_64, array, size);
		break;
	case 9:
		sort_test(init_array72, cmp_72, array, size);
		break;
	}
	kfree(array);

	return 0;
}

static int __init sort_tests_init(void)
{
	int err;

	err = perform_test(sizeof(u32));
	if (err)
		return err;

	err = perform_test(sizeof(u64));
	if (err)
		return err;

	err = perform_test(sizeof(u64)+1);
	if (err)
		return err;

	return 0;
}

static void __exit sort_tests_exit(void)
{
}

module_init(sort_tests_init);
module_exit(sort_tests_exit);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Daniel Wagner");
MODULE_DESCRIPTION("sort perfomance tests");
Signed-off-by: NDaniel Wagner <daniel.wagner@bmw-carit.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The test data arrays, containing pointers to test strings, are never
modified, so they can be const, too.  Hence mark them "const" and
"__initconst".

This moves 28 pointers from ".init.data" to ".init.rodata".
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>