Joe Perches [Thu, 25 Jun 2015 22:02:46 +0000 (15:02 -0700)]
checkpatch: check for uncommented waitqueue_active()
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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Simek [Thu, 25 Jun 2015 22:02:43 +0000 (15:02 -0700)]
drivers/firmware/memmap.c: fix kernel-doc format
Fix kernel-doc format validation to be able to use kernel-doc script for
checking it.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:41 +0000 (15:02 -0700)]
fs/ext4/super.c: use strreplace() in ext4_fill_super()
This makes a very large function a little smaller.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:38 +0000 (15:02 -0700)]
fs/jbd2/journal.c: use strreplace()
In one case, we eliminate a local variable; in the other a strlen()
call and some .text.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:36 +0000 (15:02 -0700)]
drivers/md/md.c: use strreplace()
There's no point in starting over when we meet a '/'. This also
eliminates a stack variable and a little .text.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:33 +0000 (15:02 -0700)]
drivers/base/core.c: use strreplace()
This eliminates a little .text and avoids repeating the strchr call when
we meet a '!' (which will happen at least once).
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:30 +0000 (15:02 -0700)]
lib/kobject.c: use strreplace()
There's probably not many slashes in the name, but starting over when
we see one feels wrong.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:28 +0000 (15:02 -0700)]
kernel/trace/blktrace.c: use strreplace() in do_blk_trace_setup()
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: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Liked-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:25 +0000 (15:02 -0700)]
kernel/trace/trace_events_filter.c: use strreplace()
There's no point in starting over every time we see a ','...
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rasmus Villemoes [Thu, 25 Jun 2015 22:02:22 +0000 (15:02 -0700)]
lib/string.c: introduce strreplace()
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: Rasmus 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Thu, 25 Jun 2015 22:02:19 +0000 (15:02 -0700)]
radix-tree: replace preallocated node array with linked list
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: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sudeep Holla [Thu, 25 Jun 2015 22:02:17 +0000 (15:02 -0700)]
bitmap: remove explicit newline handling using scnprintf format string
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: Sudeep Holla <sudeep.holla@arm.com>
Suggested-by: Pawel Moll <Pawel.Moll@arm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Wagner [Thu, 25 Jun 2015 22:02:14 +0000 (15:02 -0700)]
lib/sort: Add 64 bit swap function
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: Daniel Wagner <daniel.wagner@bmw-carit.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Geert Uytterhoeven [Thu, 25 Jun 2015 22:02:11 +0000 (15:02 -0700)]
hexdump: Make test data really const
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: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chris Metcalf [Thu, 25 Jun 2015 22:02:08 +0000 (15:02 -0700)]
__bitmap_parselist: fix bug in empty string handling
bitmap_parselist("", &mask, nmaskbits) will erroneously set bit zero in
the mask. The same bug is visible in cpumask_parselist() since it is
layered on top of the bitmask code, e.g. if you boot with "isolcpus=",
you will actually end up with cpu zero isolated.
The bug was introduced in commit
4b060420a596 ("bitmap, irq: add
smp_affinity_list interface to /proc/irq") when bitmap_parselist() was
generalized to support userspace as well as kernelspace.
Fixes:
4b060420a596 ("bitmap, irq: add smp_affinity_list interface to /proc/irq")
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.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>
Andrew Morton [Thu, 25 Jun 2015 22:02:05 +0000 (15:02 -0700)]
MAINTAINERS: Davidlohr has moved
Reported-by: Rob Landley <rob@landley.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Thu, 25 Jun 2015 22:02:03 +0000 (15:02 -0700)]
MAINTAINERS: Add quotation marks around names with commas
This makes it easier to copy/paste names with periods to email clients.
All the other names with commas already have quotation marks.
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>
Joe Perches [Thu, 25 Jun 2015 22:02:00 +0000 (15:02 -0700)]
MAINTAINERS: add quotation marks around names with periods
This makes it easier to copy/paste names with periods to email clients.
All the other names with periods already have quotation marks.
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>
Jim Davis [Thu, 25 Jun 2015 22:01:58 +0000 (15:01 -0700)]
MAINTAINERS: alsa-devel@alsa-project.org is moderated for non-subscribers
Fix a few inconsistent annotations to show that the alsa-devel mailing
list is moderated for non-subscribers.
Signed-off-by: Jim Davis <jim.epost@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Thu, 25 Jun 2015 22:01:55 +0000 (15:01 -0700)]
get_maintainer: fix perl 5.22/5.24 deprecated/incompatible "\C" use
Perl 5.22 emits a deprecated message when "\C" is used in a regex. Perl
5.24 will disallow it altogether.
Fix it by using [A-Z] instead of \C.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Tested-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Thu, 25 Jun 2015 22:01:52 +0000 (15:01 -0700)]
get_maintainer: emit longer section headers
Section headers can be quite long and some are very long and duplicated
for many initial characters.
The current maximum length emitted for a section header is 20 bytes (or
17 bytes then ... when the section header length is > 20).
Change that length to 50 so more of the section is shown.
Example new output:
$ ./scripts/get_maintainer.pl -f drivers/net/ethernet/broadcom/bnx2x/
Ariel Elior <ariel.elior@qlogic.com> (supporter:BROADCOM BNX2X 10 GIGABIT ETHERNET DRIVER)
netdev@vger.kernel.org (open list:BROADCOM BNX2X 10 GIGABIT ETHERNET DRIVER)
linux-kernel@vger.kernel.org (open list)
Old:
$ ./scripts/get_maintainer.pl -f drivers/net/ethernet/broadcom/bnx2x/
Ariel Elior <ariel.elior@qlogic.com> (supporter:BROADCOM BNX2X 10...)
netdev@vger.kernel.org (open list:BROADCOM BNX2X 10...)
linux-kernel@vger.kernel.org (open list)
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>
Joe Perches [Thu, 25 Jun 2015 22:01:50 +0000 (15:01 -0700)]
get_maintainer.pl: add .get_maintainer.ignore file capability
Some people prefer not to be cc'd on patches. Add an ability to have a
file (.get_maintainer.ignore) with names and email addresses that are
excluded from being listed except when specifically listed as a maintainer
in a section.
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>
Vasily Averin [Thu, 25 Jun 2015 22:01:47 +0000 (15:01 -0700)]
check_syslog_permissions() cleanup
Patch fixes drawbacks in heck_syslog_permissions() noticed by AKPM:
"from_file handling makes me cry.
That's not a boolean - it's an enumerated value with two values
currently defined.
But the code in check_syslog_permissions() treats it as a boolean and
also hardwires the knowledge that SYSLOG_FROM_PROC == 1 (or == `true`).
And the name is wrong: it should be called from_proc to match
SYSLOG_FROM_PROC."
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Josh Boyer <jwboyer@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vasily Averin [Thu, 25 Jun 2015 22:01:44 +0000 (15:01 -0700)]
security_syslog() should be called once only
The final version of commit
637241a900cb ("kmsg: honor dmesg_restrict
sysctl on /dev/kmsg") lost few hooks, as result security_syslog() are
processed incorrectly:
- open of /dev/kmsg checks syslog access permissions by using
check_syslog_permissions() where security_syslog() is not called if
dmesg_restrict is set.
- syslog syscall and /proc/kmsg calls do_syslog() where security_syslog
can be executed twice (inside check_syslog_permissions() and then
directly in do_syslog())
With this patch security_syslog() is called once only in all
syslog-related operations regardless of dmesg_restrict value.
Fixes:
637241a900cb ("kmsg: honor dmesg_restrict sysctl on /dev/kmsg")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Josh Boyer <jwboyer@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Thu, 25 Jun 2015 22:01:41 +0000 (15:01 -0700)]
netconsole: implement extended console support
printk logbuf keeps various metadata and optional key=value dictionary for
structured messages, both of which are stripped when messages are handed
to regular console drivers.
It can be useful to have this metadata and dictionary available to
netconsole consumers. This obviously makes logging via netconsole more
complete and the sequence number in particular is useful in environments
where messages may be lost or reordered in transit - e.g. when netconsole
is used to collect messages in a large cluster where packets may have to
travel congested hops to reach the aggregator. The lost and reordered
messages can easily be identified and handled accordingly using the
sequence numbers.
printk recently added extended console support which can be selected by
setting CON_EXTENDED flag. From console driver side, not much changes.
The only difference is that the text passed to the write callback is
formatted the same way as /dev/kmsg.
This patch implements extended console support for netconsole which can be
enabled by either prepending "+" to a netconsole boot param entry or
echoing 1 to "extended" file in configfs. When enabled, netconsole
transmits extended log messages with headers identical to /dev/kmsg
output.
There's one complication due to message fragments. netconsole limits the
maximum message size to 1k and messages longer than that are split into
multiple fragments. As all extended console messages should carry
matching headers and be uniquely identifiable, each extended message
fragment carries full copy of the metadata and an extra header field to
identify the specific fragment. The optional header is of the form
"ncfrag=OFF/LEN" where OFF is the byte offset into the message body and
LEN is the total length.
To avoid unnecessarily making printk format extended messages, Extended
netconsole is registered with printk when the first extended netconsole is
configured.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Thu, 25 Jun 2015 22:01:38 +0000 (15:01 -0700)]
netconsole: make all dynamic netconsoles share a mutex
Currently, each dynamic netconsole_target uses its own separate mutex to
synchronize the configuration operations.
This patch replaces the per-netconsole_target mutexes with a single
mutex - dynamic_netconsole_mutex. The reduced granularity doesn't hurt
anything, the code is minutely simpler and this'd allow adding
operations which should be synchronized across all dynamic netconsoles.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Thu, 25 Jun 2015 22:01:36 +0000 (15:01 -0700)]
netconsole: make netconsole_target->enabled a bool
netconsole uses both bool and int for boolean values. Let's convert
nt->enabled to bool for consistency.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Thu, 25 Jun 2015 22:01:33 +0000 (15:01 -0700)]
netconsole: remove unnecessary netconsole_target_get/out() from write_msg()
write_msg() grabs target_list_lock and walks target_list invoking
netpool_send_udp() on each target. Curiously, it protects each iteration
with netconsole_target_get/put() even though it never releases
target_list_lock which protects all the members.
While this doesn't harm anything, it doesn't serve any purpose either.
The items on the list can't go away while target_list_lock is held.
Remove the unnecessary get/put pair.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Thu, 25 Jun 2015 22:01:30 +0000 (15:01 -0700)]
printk: implement support for extended console drivers
printk log_buf keeps various metadata for each message including its
sequence number and timestamp. The metadata is currently available only
through /dev/kmsg and stripped out before passed onto console drivers. We
want this metadata to be available to console drivers too so that console
consumers can get full information including the metadata and dictionary,
which among other things can be used to detect whether messages got lost
in transit.
This patch implements support for extended console drivers. Consoles can
indicate that they want extended messages by setting the new CON_EXTENDED
flag and they'll be fed messages formatted the same way as /dev/kmsg.
"<level>,<sequnum>,<timestamp>,<contflag>;<message text>\n"
If extended consoles exist, in-kernel fragment assembly is disabled. This
ensures that all messages emitted to consoles have full metadata including
sequence number. The contflag carries enough information to reassemble
the fragments from the reader side trivially. Note that this only affects
/dev/kmsg. Regular console and /proc/kmsg outputs are not affected by
this change.
* Extended message formatting for console drivers is enabled iff there
are registered extended consoles.
* Comment describing /dev/kmsg message format updated to add missing
contflag field and help distinguishing variable from verbatim terms.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Thu, 25 Jun 2015 22:01:27 +0000 (15:01 -0700)]
printk: factor out message formatting from devkmsg_read()
The extended message formatting used for /dev/kmsg will be used implement
extended consoles. Factor out msg_print_ext_header() and
msg_print_ext_body() from devkmsg_read().
This is pure restructuring.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Thu, 25 Jun 2015 22:01:24 +0000 (15:01 -0700)]
printk: guard the amount written per line by devkmsg_read()
This patchset updates netconsole so that it can emit messages with the
same header as used in /dev/kmsg which gives neconsole receiver full log
information which enables things like structured logging and detection
of lost messages.
This patch (of 7):
devkmsg_read() uses 8k buffer and assumes that the formatted output
message won't overrun which seems safe given LOG_LINE_MAX, the current use
of dict and the escaping method being used; however, we're planning to use
devkmsg formatting wider and accounting for the buffer size properly isn't
that complicated.
This patch defines CONSOLE_EXT_LOG_MAX as 8192 and updates devkmsg_read()
so that it limits output accordingly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Colin Ian King [Thu, 25 Jun 2015 22:01:22 +0000 (15:01 -0700)]
drivers/misc/altera-stapl/altera.c: remove extraneous KERN_INFO prefix
The KERN_INFO prefix is being prepended to KERN_DEBUG when using the
dprink macro, Remove it as it is extraneous since we are printing the
message out as debug via dprintk().
Fixes smatch warning:
drivers/misc/altera-stapl/altera.c:2454 altera_init()
warn: KERN_* level not at start of string
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Igor M. Liplianin <liplianin@netup.ru>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josh Triplett [Thu, 25 Jun 2015 22:01:19 +0000 (15:01 -0700)]
clone: support passing tls argument via C rather than pt_regs magic
clone has some of the quirkiest syscall handling in the kernel, with a
pile of special cases, historical curiosities, and architecture-specific
calling conventions. In particular, clone with CLONE_SETTLS accepts a
parameter "tls" that the C entry point completely ignores and some
assembly entry points overwrite; instead, the low-level arch-specific
code pulls the tls parameter out of the arch-specific register captured
as part of pt_regs on entry to the kernel. That's a massive hack, and
it makes the arch-specific code only work when called via the specific
existing syscall entry points; because of this hack, any new clone-like
system call would have to accept an identical tls argument in exactly
the same arch-specific position, rather than providing a unified system
call entry point across architectures.
The first patch allows architectures to handle the tls argument via
normal C parameter passing, if they opt in by selecting
HAVE_COPY_THREAD_TLS. The second patch makes 32-bit and 64-bit x86 opt
into this.
These two patches came out of the clone4 series, which isn't ready for
this merge window, but these first two cleanup patches were entirely
uncontroversial and have acks. I'd like to go ahead and submit these
two so that other architectures can begin building on top of this and
opting into HAVE_COPY_THREAD_TLS. However, I'm also happy to wait and
send these through the next merge window (along with v3 of clone4) if
anyone would prefer that.
This patch (of 2):
clone with CLONE_SETTLS accepts an argument to set the thread-local
storage area for the new thread. sys_clone declares an int argument
tls_val in the appropriate point in the argument list (based on the
various CLONE_BACKWARDS variants), but doesn't actually use or pass along
that argument. Instead, sys_clone calls do_fork, which calls
copy_process, which calls the arch-specific copy_thread, and copy_thread
pulls the corresponding syscall argument out of the pt_regs captured at
kernel entry (knowing what argument of clone that architecture passes tls
in).
Apart from being awful and inscrutable, that also only works because only
one code path into copy_thread can pass the CLONE_SETTLS flag, and that
code path comes from sys_clone with its architecture-specific
argument-passing order. This prevents introducing a new version of the
clone system call without propagating the same architecture-specific
position of the tls argument.
However, there's no reason to pull the argument out of pt_regs when
sys_clone could just pass it down via C function call arguments.
Introduce a new CONFIG_HAVE_COPY_THREAD_TLS for architectures to opt into,
and a new copy_thread_tls that accepts the tls parameter as an additional
unsigned long (syscall-argument-sized) argument. Change sys_clone's tls
argument to an unsigned long (which does not change the ABI), and pass
that down to copy_thread_tls.
Architectures that don't opt into copy_thread_tls will continue to ignore
the C argument to sys_clone in favor of the pt_regs captured at kernel
entry, and thus will be unable to introduce new versions of the clone
syscall.
Patch co-authored by Josh Triplett and Thiago Macieira.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thiago Macieira <thiago.macieira@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Thu, 25 Jun 2015 22:01:16 +0000 (15:01 -0700)]
stddef.h: move offsetofend inside #ifndef/#endif guard, neaten
Commit
3876488444e7 ("include/stddef.h: Move offsetofend() from vfio.h
to a generic kernel header") added offsetofend outside the normal
include #ifndef/#endif guard. Move it inside.
Miscellanea:
o remove unnecessary blank line
o standardize offsetof macros whitespace style
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kees Cook [Thu, 25 Jun 2015 22:01:13 +0000 (15:01 -0700)]
mailmap: add rdunlap email auto-correction
To avoid having xenotime bounce when things like get_maintainers gives
me addresses, add Randy's current address.
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Randy Dunlap <rdunlap@infradead.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>
Pratyush Anand [Thu, 25 Jun 2015 22:01:11 +0000 (15:01 -0700)]
Mohit Kumar has moved
Mohit's email-id doesn't exist anymore as he has left the company.
Replace ST's id with mohit.kumar.dhaka@gmail.com.
Signed-off-by: Pratyush Anand <pratyush.anand@gmail.com>
Cc: Mohit Kumar <mohit.kumar.dhaka@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pratyush Anand [Thu, 25 Jun 2015 22:01:08 +0000 (15:01 -0700)]
Pratyush Anand has moved
pratyush.anand@st.com email-id doesn't exist anymore as I have left the
company. Replace ST's id with pratyush.anand@gmail.com.
Signed-off-by: Pratyush Anand <pratyush.anand@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Borkmann [Thu, 25 Jun 2015 22:01:05 +0000 (15:01 -0700)]
compiler-intel: fix wrong compiler barrier() macro
Cleanup commit
73679e508201 ("compiler-intel.h: Remove duplicate
definition") removed the double definition of __memory_barrier()
intrinsics.
However, in doing so, it also removed the preceding #undef barrier by
accident, meaning, the actual barrier() macro from compiler-gcc.h with
inline asm is still in place as __GNUC__ is provided.
Subsequently, barrier() can never be defined as __memory_barrier() from
compiler.h since it already has a definition in place and if we trust
the comment in compiler-intel.h, ecc doesn't support gcc specific asm
statements.
I don't have an ecc at hand (unsure if that's still used in the field?)
and only found this by accident during code review, a revert of that
cleanup would be simplest option.
Fixes:
73679e508201 ("compiler-intel.h: Remove duplicate definition")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
Cc: Pranith Kumar <bobby.prani@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: mancha security <mancha1@zoho.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Thu, 25 Jun 2015 22:01:02 +0000 (15:01 -0700)]
compiler-gcc: integrate the various compiler-gcc[345].h files
As gcc major version numbers are going to advance rather rapidly in the
future, there's no real value in separate files for each compiler
version.
Deduplicate some of the macros #defined in each file too.
Neaten comments using normal kernel commenting style.
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Sasha Levin <levinsasha928@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Alan Modra <amodra@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Thu, 25 Jun 2015 22:01:00 +0000 (15:01 -0700)]
compiler-gcc.h: neatening
- Move the inline and noinline blocks together
- Comment neatening
- Alignment of __attribute__ uses
- Consistent naming of __must_be_array macro argument
- Multiline macro neatening
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Sasha Levin <levinsasha928@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Alan Modra <amodra@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Iago López Galeiras [Thu, 25 Jun 2015 22:00:57 +0000 (15:00 -0700)]
fs, proc: introduce CONFIG_PROC_CHILDREN
Commit
818411616baf ("fs, proc: introduce /proc/<pid>/task/<tid>/children
entry") introduced the children entry for checkpoint restore and the
file is only available on kernels configured with CONFIG_EXPERT and
CONFIG_CHECKPOINT_RESTORE.
This is available in most distributions (Fedora, Debian, Ubuntu, CoreOS)
because they usually enable CONFIG_EXPERT and CONFIG_CHECKPOINT_RESTORE.
But Arch does not enable CONFIG_EXPERT or CONFIG_CHECKPOINT_RESTORE.
However, the children proc file is useful outside of checkpoint restore.
I would like to use it in rkt. The rkt process exec() another program
it does not control, and that other program will fork()+exec() a child
process. I would like to find the pid of the child process from an
external tool without iterating in /proc over all processes to find
which one has a parent pid equal to rkt.
This commit introduces CONFIG_PROC_CHILDREN and makes
CONFIG_CHECKPOINT_RESTORE select it. This allows enabling
/proc/<pid>/task/<tid>/children without needing to enable
CONFIG_CHECKPOINT_RESTORE and CONFIG_EXPERT.
Alban tested that /proc/<pid>/task/<tid>/children is present when the
kernel is configured with CONFIG_PROC_CHILDREN=y but without
CONFIG_CHECKPOINT_RESTORE
Signed-off-by: Iago López Galeiras <iago@endocode.com>
Tested-by: Alban Crequy <alban@endocode.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Djalal Harouni <djalal@endocode.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexey Dobriyan [Thu, 25 Jun 2015 22:00:54 +0000 (15:00 -0700)]
proc: fix PAGE_SIZE limit of /proc/$PID/cmdline
/proc/$PID/cmdline truncates output at PAGE_SIZE. It is easy to see with
$ cat /proc/self/cmdline $(seq 1037) 2>/dev/null
However, command line size was never limited to PAGE_SIZE but to 128 KB
and relatively recently limitation was removed altogether.
People noticed and ask questions:
http://stackoverflow.com/questions/199130/how-do-i-increase-the-proc-pid-cmdline-4096-byte-limit
seq file interface is not OK, because it kmalloc's for whole output and
open + read(, 1) + sleep will pin arbitrary amounts of kernel memory. To
not do that, limit must be imposed which is incompatible with arbitrary
sized command lines.
I apologize for hairy code, but this it direct consequence of command line
layout in memory and hacks to support things like "init [3]".
The loops are "unrolled" otherwise it is either macros which hide control
flow or functions with 7-8 arguments with equal line count.
There should be real setproctitle(2) or something.
[akpm@linux-foundation.org: fix a billion min() warnings]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Tested-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexey Dobriyan [Thu, 25 Jun 2015 22:00:51 +0000 (15:00 -0700)]
prctl: more prctl(PR_SET_MM_*) checks
Individual prctl(PR_SET_MM_*) calls do some checking to maintain a
consistent view of mm->arg_start et al fields, but not enough. In
particular PR_SET_MM_ARG_START/PR_SET_MM_ARG_END/ R_SET_MM_ENV_START/
PR_SET_MM_ENV_END only check that the address lies in an existing VMA,
but don't check that the start address is lower than the end address _at
all_.
Consolidate all consistency checks, so there will be no difference in
the future between PR_SET_MM_MAP and individual PR_SET_MM_* calls.
The program below makes both ARGV and ENVP areas be reversed. It makes
/proc/$PID/cmdline show garbage (it doesn't oops by luck).
#include <sys/mman.h>
#include <sys/prctl.h>
#include <unistd.h>
enum {PAGE_SIZE=4096};
int main(void)
{
void *p;
p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
#define PR_SET_MM 35
#define PR_SET_MM_ARG_START 8
#define PR_SET_MM_ARG_END 9
#define PR_SET_MM_ENV_START 10
#define PR_SET_MM_ENV_END 11
prctl(PR_SET_MM, PR_SET_MM_ARG_START, (unsigned long)p + PAGE_SIZE - 1, 0, 0);
prctl(PR_SET_MM, PR_SET_MM_ARG_END, (unsigned long)p, 0, 0);
prctl(PR_SET_MM, PR_SET_MM_ENV_START, (unsigned long)p + PAGE_SIZE - 1, 0, 0);
prctl(PR_SET_MM, PR_SET_MM_ENV_END, (unsigned long)p, 0, 0);
pause();
return 0;
}
[akpm@linux-foundation.org: tidy code, tweak comment]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Thu, 25 Jun 2015 22:00:48 +0000 (15:00 -0700)]
avr32: use for_each_sg()
This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls. Since avr32 doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element. But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Thu, 25 Jun 2015 22:00:46 +0000 (15:00 -0700)]
frv: use for_each_sg()
This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls. Since frv doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element. But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tobias Klauser [Thu, 25 Jun 2015 22:00:43 +0000 (15:00 -0700)]
frv: remove unused inline function is_in_rom()
The function is not used anywhere in the tree (anymore) and this is the
last remaining instance, so remove it.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Streetman [Thu, 25 Jun 2015 22:00:40 +0000 (15:00 -0700)]
zpool: remove zpool_evict()
Remove zpool_evict() helper function. As zbud is currently the only
zpool implementation that supports eviction, add zpool and zpool_ops
references to struct zbud_pool and directly call zpool_ops->evict(zpool,
handle) on eviction.
Currently zpool provides the zpool_evict helper which locks the zpool
list lock and searches through all pools to find the specific one
matching the caller, and call the corresponding zpool_ops->evict
function. However, this is unnecessary, as the zbud pool can simply
keep a reference to the zpool that created it, as well as the zpool_ops,
and directly call the zpool_ops->evict function, when it needs to evict
a page. This avoids a spinlock and list search in zpool for each
eviction.
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjennings@variantweb.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Streetman [Thu, 25 Jun 2015 22:00:37 +0000 (15:00 -0700)]
zpool: change pr_info to pr_debug
Change the pr_info() calls to pr_debug(). There's no need for the extra
verbosity in the log. Also change the msg formats to be consistent.
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Ganesh Mahendran <opensource.ganesh@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Streetman [Thu, 25 Jun 2015 22:00:35 +0000 (15:00 -0700)]
zswap: runtime enable/disable
Change the "enabled" parameter to be configurable at runtime. Remove the
enabled check from init(), and move it to the frontswap store() function;
when enabled, pages will be stored, and when disabled, pages won't be
stored.
This is almost identical to Seth's patch from 2 years ago:
http://lkml.iu.edu/hypermail/linux/kernel/1307.2/04289.html
[akpm@linux-foundation.org: tweak documentation]
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Suggested-by: Seth Jennings <sjennings@variantweb.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:32 +0000 (15:00 -0700)]
zram: check comp algorithm availability earlier
Improvement idea by Marcin Jabrzyk.
comp_algorithm_store() silently accepts any supplied algorithm name,
because zram performs algorithm availability check later, during the
device configuration phase in disksize_store() and emits the following
error:
"zram: Cannot initialise %s compressing backend"
this error line is somewhat generic and, besides, can indicate a failed
attempt to allocate compression backend's working buffers.
add algorithm availability check to comp_algorithm_store():
echo lzz > /sys/block/zram0/comp_algorithm
-bash: echo: write error: Invalid argument
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reported-by: Marcin Jabrzyk <m.jabrzyk@samsung.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:29 +0000 (15:00 -0700)]
zram: cut trailing newline in algorithm name
Supplied sysfs values sometimes contain new-line symbols (echo vs. echo
-n), which we also copy as a compression algorithm name. it works fine
when we lookup for compression algorithm, because we use sysfs_streq()
which takes care of new line symbols. however, it doesn't look nice when
we print compression algorithm name if zcomp_create() failed:
zram: Cannot initialise LXZ
compressing backend
cut trailing new-line, so the error string will look like
zram: Cannot initialise LXZ compressing backend
we also now can replace sysfs_streq() in zcomp_available_show() with
strcmp().
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:27 +0000 (15:00 -0700)]
zram: cosmetic zram_bvec_write() cleanup
`bool locked' local variable tells us if we should perform
zcomp_strm_release() or not (jumped to `out' label before
zcomp_strm_find() occurred), which is equivalent to `zstrm' being or not
being NULL. remove `locked' and check `zstrm' instead.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:24 +0000 (15:00 -0700)]
zram: add dynamic device add/remove functionality
We currently don't support on-demand device creation. The one and only
way to have N zram devices is to specify num_devices module parameter
(default value: 1). IOW if, for some reason, at some point, user wants
to have N + 1 devies he/she must umount all the existing devices, unload
the module, load the module passing num_devices equals to N + 1. And do
this again, if needed.
This patch introduces zram control sysfs class, which has two sysfs
attrs:
- hot_add -- add a new zram device
- hot_remove -- remove a specific (device_id) zram device
hot_add sysfs attr is read-only and has only automatic device id
assignment mode (as requested by Minchan Kim). read operation performed
on this attr creates a new zram device and returns back its device_id or
error status.
Usage example:
# add a new specific zram device
cat /sys/class/zram-control/hot_add
2
# remove a specific zram device
echo 4 > /sys/class/zram-control/hot_remove
Returning zram_add() error code back to user (-ENOMEM in this case)
cat /sys/class/zram-control/hot_add
cat: /sys/class/zram-control/hot_add: Cannot allocate memory
NOTE, there might be users who already depend on the fact that at least
zram0 device gets always created by zram_init(). Preserve this behavior.
[minchan@kernel.org: use zram->claim to avoid lockdep splat]
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:21 +0000 (15:00 -0700)]
zram: close race by open overriding
[ Original patch from Minchan Kim <minchan@kernel.org> ]
Commit
ba6b17d68c8e ("zram: fix umount-reset_store-mount race
condition") introduced bdev->bd_mutex to protect a race between mount
and reset. At that time, we don't have dynamic zram-add/remove feature
so it was okay.
However, as we introduce dynamic device feature, bd_mutex became
trouble.
CPU 0
echo 1 > /sys/block/zram<id>/reset
-> kernfs->s_active(A)
-> zram:reset_store->bd_mutex(B)
CPU 1
echo <id> > /sys/class/zram/zram-remove
->zram:zram_remove: bd_mutex(B)
-> sysfs_remove_group
-> kernfs->s_active(A)
IOW, AB -> BA deadlock
The reason we are holding bd_mutex for zram_remove is to prevent
any incoming open /dev/zram[0-9]. Otherwise, we could remove zram
others already have opened. But it causes above deadlock problem.
To fix the problem, this patch overrides block_device.open and
it returns -EBUSY if zram asserts he claims zram to reset so any
incoming open will be failed so we don't need to hold bd_mutex
for zram_remove ayn more.
This patch is to prepare for zram-add/remove feature.
[sergey.senozhatsky@gmail.com: simplify reset_store()]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:19 +0000 (15:00 -0700)]
zram: return zram device_id from zram_add()
This patch prepares zram to enable on-demand device creation.
zram_add() performs automatic device_id assignment and returns
new device id (>= 0) or error code (< 0).
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:16 +0000 (15:00 -0700)]
zram: trivial: correct flag operations comment
We don't have meta->tb_lock anymore and use meta table entry bit_spin_lock
instead. update corresponding comment.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:14 +0000 (15:00 -0700)]
zram: report every added and removed device
With dynamic device creation/removal (which will be introduced later in
the series) printing num_devices in zram_init() will not make a lot of
sense, as well as printing the number of destroyed devices in
destroy_devices(). Print per-device action (added/removed) in zram_add()
and zram_remove() instead.
Example:
[ 3645.259652] zram: Added device: zram5
[ 3646.152074] zram: Added device: zram6
[ 3650.585012] zram: Removed device: zram5
[ 3655.845584] zram: Added device: zram8
[ 3660.975223] zram: Removed device: zram6
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:11 +0000 (15:00 -0700)]
zram: remove max_num_devices limitation
Limiting the number of zram devices to 32 (default max_num_devices value)
is confusing, let's drop it. A user with 2TB or 4TB of RAM, for example,
can request as many devices as he can handle.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:08 +0000 (15:00 -0700)]
zram: reorganize code layout
This patch looks big, but basically it just moves code blocks.
No functional changes.
Our current code layout looks like a sandwitch.
For example,
a) between read/write handlers, we have update_used_max() helper function:
static int zram_decompress_page
static int zram_bvec_read
static inline void update_used_max
static int zram_bvec_write
static int zram_bvec_rw
b) RW request handlers __zram_make_request/zram_bio_discard are divided by
sysfs attr reset_store() function and corresponding zram_reset_device()
handler:
static void zram_bio_discard
static void zram_reset_device
static ssize_t disksize_store
static ssize_t reset_store
static void __zram_make_request
c) we first a bunch of sysfs read/store functions. then a number of
one-liners, then helper functions, RW functions, sysfs functions, helper
functions again, and so on.
Reorganize layout to be more logically grouped (a brief description,
`cat zram_drv.c | grep static` gives a bigger picture):
-- one-liners: zram_test_flag/etc.
-- helpers: is_partial_io/update_position/etc
-- sysfs attr show/store functions + ZRAM_ATTR_RO() generated stats
show() functions
exception: reset and disksize store functions are required to be after
meta() functions. because we do device create/destroy actions in these
sysfs handlers.
-- "mm" functions: meta get/put, meta alloc/free, page free
static inline bool zram_meta_get
static inline void zram_meta_put
static void zram_meta_free
static struct zram_meta *zram_meta_alloc
static void zram_free_page
-- a block of I/O functions
static int zram_decompress_page
static int zram_bvec_read
static int zram_bvec_write
static void zram_bio_discard
static int zram_bvec_rw
static void __zram_make_request
static void zram_make_request
static void zram_slot_free_notify
static int zram_rw_page
-- device contol: add/remove/init/reset functions (+zram-control class
will sit here)
static int zram_reset_device
static ssize_t reset_store
static ssize_t disksize_store
static int zram_add
static void zram_remove
static int __init zram_init
static void __exit zram_exit
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:06 +0000 (15:00 -0700)]
zram: use idr instead of `zram_devices' array
This patch makes some preparations for on-demand device add/remove
functionality.
Remove `zram_devices' array and switch to id-to-pointer translation (idr).
idr doesn't bloat zram struct with additional members, f.e. list_head,
yet still provides ability to match the device_id with the device pointer.
No user-space visible changes.
[Julia.Lawall@lip6.fr: return -ENOMEM when `queue' alloc fails]
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reported-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:03 +0000 (15:00 -0700)]
zram: cosmetic ZRAM_ATTR_RO code formatting tweak
Fix a misplaced backslash.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey Senozhatsky [Thu, 25 Jun 2015 22:00:00 +0000 (15:00 -0700)]
zram: add `compact` sysfs entry to documentation
We currently don't support zram on-demand device creation. The only way
to have N zram devices is to specify num_devices module parameter (default
value 1). That means that if, for some reason, at some point, user wants
to have N + 1 devies he/she must umount all the existing devices, unload
the module, load the module passing num_devices equals to N + 1.
This patchset introduces zram-control sysfs class, which has two sysfs
attrs:
- hot_add -- add a new zram device
- hot_remove -- remove a specific (device_id) zram device
Usage example:
# add a new specific zram device
cat /sys/class/zram-control/hot_add
1
# remove a specific zram device
echo 4 > /sys/class/zram-control/hot_remove
This patch (of 10):
Briefly describe missing `compact` sysfs entry.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marcin Jabrzyk [Thu, 25 Jun 2015 21:59:58 +0000 (14:59 -0700)]
zsmalloc: remove obsolete ZSMALLOC_DEBUG
The DEBUG define in zsmalloc is useless, there is no usage of it at all.
Signed-off-by: Marcin Jabrzyk <m.jabrzyk@samsung.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marcin Jabrzyk [Thu, 25 Jun 2015 21:59:55 +0000 (14:59 -0700)]
zram: remove obsolete ZRAM_DEBUG option
This config option doesn't provide any usage for zram.
Signed-off-by: Marcin Jabrzyk <m.jabrzyk@samsung.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dominik Dingel [Thu, 25 Jun 2015 21:59:52 +0000 (14:59 -0700)]
s390/mm: change HPAGE_SHIFT type to int
With making HPAGE_SHIFT an unsigned integer we also accidentally changed
pageblock_order. In order to avoid compiler warnings we make
HPAGE_SHFIT an int again.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dominik Dingel [Thu, 25 Jun 2015 21:59:49 +0000 (14:59 -0700)]
s390/mm: forward check for huge pmds to pmd_large()
We already do the check in pmd_large, so we can just forward the call.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dominik Dingel [Thu, 25 Jun 2015 21:59:47 +0000 (14:59 -0700)]
s390/hugetlb: remove dead code for sw emulated huge pages
We now support only hugepages on hardware with EDAT1 support. So we
remove the prepare/release_hugepage hooks and simplify set_huge_pte_at
and huge_ptep_get.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dominik Dingel [Thu, 25 Jun 2015 21:59:44 +0000 (14:59 -0700)]
mm/hugetlb: remove arch_prepare/release_hugepage from arch headers
Nobody used these hooks so they were removed from common code, and can now
be removed from the architectures.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dominik Dingel [Thu, 25 Jun 2015 21:59:42 +0000 (14:59 -0700)]
mm/hugetlb: remove unused arch hook prepare/release_hugepage
With s390 dropping support for emulated hugepages, the last user of
arch_prepare_hugepage and arch_release_hugepage is gone.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dominik Dingel [Thu, 25 Jun 2015 21:59:39 +0000 (14:59 -0700)]
s390/mm: make hugepages_supported a boot time decision
There is a potential bug with KVM and hugetlbfs if the hardware does not
support hugepages (EDAT1). We fix this by making EDAT1 a hard requirement
for hugepages and therefore removing and simplifying code.
As s390, with the sw-emulated hugepages, was the only user of
arch_prepare/release_hugepage I also removed theses calls from common and
other architecture code.
This patch (of 5):
By dropping support for hugepages on machines which do not have the
hardware feature EDAT1, we fix a potential s390 KVM bug.
The bug would happen if a guest is backed by hugetlbfs (not supported
currently), but does not get pagetables with PGSTE. This would lead to
random memory overwrites.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Thu, 25 Jun 2015 03:47:21 +0000 (20:47 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge first patchbomb from Andrew Morton:
- a few misc things
- ocfs2 udpates
- kernel/watchdog.c feature work (took ages to get right)
- most of MM. A few tricky bits are held up and probably won't make 4.2.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (91 commits)
mm: kmemleak_alloc_percpu() should follow the gfp from per_alloc()
mm, thp: respect MPOL_PREFERRED policy with non-local node
tmpfs: truncate prealloc blocks past i_size
mm/memory hotplug: print the last vmemmap region at the end of hot add memory
mm/mmap.c: optimization of do_mmap_pgoff function
mm: kmemleak: optimise kmemleak_lock acquiring during kmemleak_scan
mm: kmemleak: avoid deadlock on the kmemleak object insertion error path
mm: kmemleak: do not acquire scan_mutex in kmemleak_do_cleanup()
mm: kmemleak: fix delete_object_*() race when called on the same memory block
mm: kmemleak: allow safe memory scanning during kmemleak disabling
memcg: convert mem_cgroup->under_oom from atomic_t to int
memcg: remove unused mem_cgroup->oom_wakeups
frontswap: allow multiple backends
x86, mirror: x86 enabling - find mirrored memory ranges
mm/memblock: allocate boot time data structures from mirrored memory
mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute
mm: do not ignore mapping_gfp_mask in page cache allocation paths
mm/cma.c: fix typos in comments
mm/oom_kill.c: print points as unsigned int
mm/hugetlb: handle races in alloc_huge_page and hugetlb_reserve_pages
...
Linus Torvalds [Thu, 25 Jun 2015 03:42:21 +0000 (20:42 -0700)]
Merge tag 'please-pull-pstore' of git://git./linux/kernel/git/aegl/linux
Pull pstore updates from Tony Luck:
"Miscellaneous pstore improvements"
* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
ramoops: make it possible to change mem_type param.
pstore/ram: verify ramoops header before saving record
fs/pstore: Optimization function ramoops_init_przs
fs/pstore: update the backend parameter in pstore module
pstore: do not use message compression without lock
Linus Torvalds [Thu, 25 Jun 2015 03:38:29 +0000 (20:38 -0700)]
Merge tag 'for-f2fs-4.2' of git://git./linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"New features:
- per-file encryption (e.g., ext4)
- FALLOC_FL_ZERO_RANGE
- FALLOC_FL_COLLAPSE_RANGE
- RENAME_WHITEOUT
Major enhancement/fixes:
- recovery broken superblocks
- enhance f2fs_trim_fs with a discard_map
- fix a race condition on dentry block allocation
- fix a deadlock during summary operation
- fix a missing fiemap result
.. and many minor bug fixes and clean-ups were done"
* tag 'for-f2fs-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (83 commits)
f2fs: do not trim preallocated blocks when truncating after i_size
f2fs crypto: add alloc_bounce_page
f2fs crypto: fix to handle errors likewise ext4
f2fs: drop the volatile_write flag only
f2fs: skip committing valid superblock
f2fs: setting discard option in parse_options()
f2fs: fix to return exact trimmed size
f2fs: support FALLOC_FL_INSERT_RANGE
f2fs: hide common code in f2fs_replace_block
f2fs: disable the discard option when device doesn't support
f2fs crypto: remove alloc_page for bounce_page
f2fs: fix a deadlock for summary page lock vs. sentry_lock
f2fs crypto: clean up error handling in f2fs_fname_setup_filename
f2fs crypto: avoid f2fs_inherit_context for symlink
f2fs crypto: do not set encryption policy for non-directory by ioctl
f2fs crypto: allow setting encryption policy once
f2fs crypto: check context consistent for rename2
f2fs: avoid duplicated code by reusing f2fs_read_end_io
f2fs crypto: use per-inode tfm structure
f2fs: recovering broken superblock during mount
...
Linus Torvalds [Thu, 25 Jun 2015 03:07:10 +0000 (20:07 -0700)]
Merge branch 'for_linus' of git://git./linux/kernel/git/jack/linux-fs
Pull UDF fixes and cleanups from Jan Kara:
"The contains some small fixes and improvements in error handling for
UDF.
Bundled is also one ext3 coding style fix and a fix in quota
documentation"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
udf: fix udf_load_pvoldesc()
udf: remove double err declaration in udf_file_write_iter()
UDF: support NFSv2 export
fs: ext3: super: fixed a space coding style issue
quota: Update documentation
udf: Return error from udf_find_entry()
udf: Make udf_get_filename() return error instead of 0 length file name
udf: bug on exotic flag in udf_get_filename()
udf: improve error management in udf_CS0toNLS()
udf: improve error management in udf_CS0toUTF8()
udf: unicode: update function name in comments
udf: remove unnecessary test in udf_build_ustr_exact()
udf: Return -ENOMEM when allocation fails in udf_get_filename()
Linus Torvalds [Thu, 25 Jun 2015 03:01:36 +0000 (20:01 -0700)]
Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6
Pull documentation updates from Jonathan Corbet:
"The main thing here is Ingo's big subdirectory documenting feature
support for each architecture. Beyond that, it's the usual pile of
fixes, tweaks, and small additions"
* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits)
doc:md: fix typo in md.txt.
Documentation/mic/mpssd: don't build x86 userspace when cross compiling
Documentation/prctl: don't build tsc tests when cross compiling
Documentation/vDSO: don't build tests when cross compiling
Doc:ABI/testing: Fix typo in sysfs-bus-fcoe
Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl
Doc: Change wikipedia's URL from http to https
Documentation/kernel-parameters: add missing pciserial to the earlyprintk
Doc:pps: Fix typo in pps.txt
kbuild : Fix documentation of INSTALL_HDR_PATH
Documentation: filesystems: updated struct file_operations documentation in vfs.txt
kbuild: edit explanation of clean-files variable
Doc: ja_JP: Fix typo in HOWTO
Move freefall program from Documentation/ to tools/
Documentation: ARM: EXYNOS: Describe boot loaders interface
Doc:nfc: Fix typo in nfc-hci.txt
vfs: Minor documentation fix
Doc: networking: txtimestamp: fix printf format warning
Documentation, intel_pstate: Improve legacy mode internal governors description
Documentation: extend use case for EXPORT_SYMBOL_GPL()
...
Linus Torvalds [Thu, 25 Jun 2015 02:56:58 +0000 (19:56 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input
Pull input subsystem updates from Dmitry Torokhov:
"Thanks to Samuel Thibault input device (keyboard) LEDs are no longer
hardwired within the input core but use LED subsystem and so allow use
of different triggers; Hans de Goede did a large update for the ALPS
touchpad driver; we have new TI drv2665 haptics driver and DA9063
OnKey driver, and host of other drivers got various fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (55 commits)
Input: pixcir_i2c_ts - fix receive error
MAINTAINERS: remove non existent input mt git tree
Input: improve usage of gpiod API
tty/vt/keyboard: define LED triggers for VT keyboard lock states
tty/vt/keyboard: define LED triggers for VT LED states
Input: export LEDs as class devices in sysfs
Input: cyttsp4 - use swap() in cyttsp4_get_touch()
Input: goodix - do not explicitly set evbits in input device
Input: goodix - export id and version read from device
Input: goodix - fix variable length array warning
Input: goodix - fix alignment issues
Input: add OnKey driver for DA9063 MFD part
Input: elan_i2c - add product IDs FW names
Input: elan_i2c - add support for multi IC type and iap format
Input: focaltech - report finger width to userspace
tty: remove platform_sysrq_reset_seq
Input: synaptics_i2c - use proper boolean values
Input: psmouse - use true instead of 1 for boolean values
Input: cyapa - fix a few typos in comments
Input: stmpe-ts - enforce device tree only mode
...
Linus Torvalds [Thu, 25 Jun 2015 02:52:06 +0000 (19:52 -0700)]
Merge tag 'edac_for_4.2_2' of git://git./linux/kernel/git/bp/bp
Pull EDAC updates from Borislav Petkov:
- New APM X-Gene SoC EDAC driver (Loc Ho)
- AMD error injection module improvements (Aravind Gopalakrishnan)
- Altera Arria 10 support (Thor Thayer)
- misc fixes and cleanups all over the place
* tag 'edac_for_4.2_2' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp: (28 commits)
EDAC: Update Documentation/edac.txt
EDAC: Fix typos in Documentation/edac.txt
EDAC, mce_amd_inj: Set MISCV on injection
EDAC, mce_amd_inj: Move bit preparations before the injection
EDAC, mce_amd_inj: Cleanup and simplify README
EDAC, altera: Do not allow suspend when EDAC is enabled
EDAC, mce_amd_inj: Make inj_type static
arm: socfpga: dts: Add Arria10 SDRAM EDAC DTS support
EDAC, altera: Add Arria10 EDAC support
EDAC, altera: Refactor for Altera CycloneV SoC
EDAC, altera: Generalize driver to use DT Memory size
EDAC, mce_amd_inj: Add README file
EDAC, mce_amd_inj: Add individual permissions field to dfs_node
EDAC, mce_amd_inj: Modify flags attribute to use string arguments
EDAC, mce_amd_inj: Read out number of MCE banks from the hardware
EDAC, mce_amd_inj: Use MCE_INJECT_GET macro for bank node too
EDAC, xgene: Fix cpuid abuse
EDAC, mpc85xx: Extend error address to 64 bit
EDAC, mpc8xxx: Adapt for FSL SoC
EDAC, edac_stub: Drop arch-specific include
...
Linus Torvalds [Thu, 25 Jun 2015 02:21:02 +0000 (19:21 -0700)]
Merge tag 'pinctrl-v4.2-1' of git://git./linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij:
"Here is the bulk of pin control changes for the v4.2 series: Quite a
lot of new SoC subdrivers and two new main drivers this time, apart
from that business as usual.
Details:
Core functionality:
- Enable exclusive pin ownership: it is possible to flag a pin
controller so that GPIO and other functions cannot use a single pin
simultaneously.
New drivers:
- NXP LPC18xx System Control Unit pin controller
- Imagination Pistachio SoC pin controller
New subdrivers:
- Freescale i.MX7d SoC
- Intel Sunrisepoint-H PCH
- Renesas PFC R8A7793
- Renesas PFC R8A7794
- Mediatek MT6397, MT8127
- SiRF Atlas 7
- Allwinner A33
- Qualcomm MSM8660
- Marvell Armada 395
- Rockchip RK3368
Cleanups:
- A big cleanup of the Marvell MVEBU driver rectifying it to
correspond to reality
- Drop platform device probing from the SH PFC driver, we are now a
DT only shop for SuperH
- Drop obsolte multi-platform check for SH PFC
- Various janitorial: constification, grammar etc
Improvements:
- The AT91 GPIO portions now supports the set_multiple() feature
- Split out SPI pins on the Xilinx Zynq
- Support DTs without specific function nodes in the i.MX driver"
* tag 'pinctrl-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (99 commits)
pinctrl: rockchip: add support for the rk3368
pinctrl: rockchip: generalize perpin driver-strength setting
pinctrl: sh-pfc: r8a7794: add SDHI pin groups
pinctrl: sh-pfc: r8a7794: add MMCIF pin groups
pinctrl: sh-pfc: add R8A7794 PFC support
pinctrl: make pinctrl_register() return proper error code
pinctrl: mvebu: armada-39x: add support for Armada 395 variant
pinctrl: mvebu: armada-39x: add missing SATA functions
pinctrl: mvebu: armada-39x: add missing PCIe functions
pinctrl: mvebu: armada-38x: add ptp functions
pinctrl: mvebu: armada-38x: add ua1 functions
pinctrl: mvebu: armada-38x: add nand functions
pinctrl: mvebu: armada-38x: add sata functions
pinctrl: mvebu: armada-xp: add dram functions
pinctrl: mvebu: armada-xp: add nand rb function
pinctrl: mvebu: armada-xp: add spi1 function
pinctrl: mvebu: armada-39x: normalize ref clock naming
pinctrl: mvebu: armada-xp: rename spi to spi0
pinctrl: mvebu: armada-370: align spi1 clock pin naming
pinctrl: mvebu: armada-370: align VDD cpu-pd pin naming with datasheet
...
Linus Torvalds [Thu, 25 Jun 2015 01:57:00 +0000 (18:57 -0700)]
Merge tag 'backlight-for-linus-4.2' of git://git./linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
"Changes to existing drivers:
- supply MODULE_DEVICE_TABLE() to ensure probing
- constify struct; da9052_bl
- enable compile test; lcd_l4f00242t03, lcd_lms283fg05, backlight_gpio
- suspend/resume bugfix; lp855x_bl
- devm_gpiod_get_optional() API fixup; pwm_bl
- error handling fixup; backlight"
* tag 'backlight-for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
backlight: Change the return type of backlight_update_status() to int
backlight: pwm_bl: Simplify usage of devm_gpiod_get_optional
backlight: lp855x: Don't clear level on suspend/blank
backlight: Allow compile test of GPIO consumers if !GPIOLIB
video: backlight: da9052: Constify platform_device_id
gpio-backlight: Discover driver during boot time
Larry Finger [Wed, 24 Jun 2015 23:58:51 +0000 (16:58 -0700)]
mm: kmemleak_alloc_percpu() should follow the gfp from per_alloc()
Beginning at commit
d52d3997f843 ("ipv6: Create percpu rt6_info"), the
following INFO splat is logged:
===============================
[ INFO: suspicious RCU usage. ]
4.1.0-rc7-next-
20150612 #1 Not tainted
-------------------------------
kernel/sched/core.c:7318 Illegal context switch in RCU-bh read-side critical section!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
3 locks held by systemd/1:
#0: (rtnl_mutex){+.+.+.}, at: [<
ffffffff815f0c8f>] rtnetlink_rcv+0x1f/0x40
#1: (rcu_read_lock_bh){......}, at: [<
ffffffff816a34e2>] ipv6_add_addr+0x62/0x540
#2: (addrconf_hash_lock){+...+.}, at: [<
ffffffff816a3604>] ipv6_add_addr+0x184/0x540
stack backtrace:
CPU: 0 PID: 1 Comm: systemd Not tainted 4.1.0-rc7-next-
20150612 #1
Hardware name: TOSHIBA TECRA A50-A/TECRA A50-A, BIOS Version 4.20 04/17/2014
Call Trace:
dump_stack+0x4c/0x6e
lockdep_rcu_suspicious+0xe7/0x120
___might_sleep+0x1d5/0x1f0
__might_sleep+0x4d/0x90
kmem_cache_alloc+0x47/0x250
create_object+0x39/0x2e0
kmemleak_alloc_percpu+0x61/0xe0
pcpu_alloc+0x370/0x630
Additional backtrace lines are truncated. In addition, the above splat
is followed by several "BUG: sleeping function called from invalid
context at mm/slub.c:1268" outputs. As suggested by Martin KaFai Lau,
these are the clue to the fix. Routine kmemleak_alloc_percpu() always
uses GFP_KERNEL for its allocations, whereas it should follow the gfp
from its callers.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: <stable@vger.kernel.org> [3.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Wed, 24 Jun 2015 23:58:48 +0000 (16:58 -0700)]
mm, thp: respect MPOL_PREFERRED policy with non-local node
Since commit
077fcf116c8c ("mm/thp: allocate transparent hugepages on
local node"), we handle THP allocations on page fault in a special way -
for non-interleave memory policies, the allocation is only attempted on
the node local to the current CPU, if the policy's nodemask allows the
node.
This is motivated by the assumption that THP benefits cannot offset the
cost of remote accesses, so it's better to fallback to base pages on the
local node (which might still be available, while huge pages are not due
to fragmentation) than to allocate huge pages on a remote node.
The nodemask check prevents us from violating e.g. MPOL_BIND policies
where the local node is not among the allowed nodes. However, the
current implementation can still give surprising results for the
MPOL_PREFERRED policy when the preferred node is different than the
current CPU's local node.
In such case we should honor the preferred node and not use the local
node, which is what this patch does. If hugepage allocation on the
preferred node fails, we fall back to base pages and don't try other
nodes, with the same motivation as is done for the local node hugepage
allocations. The patch also moves the MPOL_INTERLEAVE check around to
simplify the hugepage specific test.
The difference can be demonstrated using in-tree transhuge-stress test
on the following 2-node machine where half memory on one node was
occupied to show the difference.
> numactl --hardware
available: 2 nodes (0-1)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 24 25 26 27 28 29 30 31 32 33 34 35
node 0 size: 7878 MB
node 0 free: 3623 MB
node 1 cpus: 12 13 14 15 16 17 18 19 20 21 22 23 36 37 38 39 40 41 42 43 44 45 46 47
node 1 size: 8045 MB
node 1 free: 7818 MB
node distances:
node 0 1
0: 10 21
1: 21 10
Before the patch:
> numactl -p0 -C0 ./transhuge-stress
transhuge-stress: 2.197 s/loop, 0.276 ms/page, 7249.168 MiB/s 7962 succeed, 0 failed, 1786 different pages
> numactl -p0 -C12 ./transhuge-stress
transhuge-stress: 2.962 s/loop, 0.372 ms/page, 5376.172 MiB/s 7962 succeed, 0 failed, 3873 different pages
Number of successful THP allocations corresponds to free memory on node 0 in
the first case and node 1 in the second case, i.e. -p parameter is ignored and
cpu binding "wins".
After the patch:
> numactl -p0 -C0 ./transhuge-stress
transhuge-stress: 2.183 s/loop, 0.274 ms/page, 7295.516 MiB/s 7962 succeed, 0 failed, 1760 different pages
> numactl -p0 -C12 ./transhuge-stress
transhuge-stress: 2.878 s/loop, 0.361 ms/page, 5533.638 MiB/s 7962 succeed, 0 failed, 1750 different pages
> numactl -p1 -C0 ./transhuge-stress
transhuge-stress: 4.628 s/loop, 0.581 ms/page, 3440.893 MiB/s 7962 succeed, 0 failed, 3918 different pages
The -p parameter is respected regardless of cpu binding.
> numactl -C0 ./transhuge-stress
transhuge-stress: 2.202 s/loop, 0.277 ms/page, 7230.003 MiB/s 7962 succeed, 0 failed, 1750 different pages
> numactl -C12 ./transhuge-stress
transhuge-stress: 3.020 s/loop, 0.379 ms/page, 5273.324 MiB/s 7962 succeed, 0 failed, 3916 different pages
Without -p parameter, hugepage restriction to CPU-local node works as before.
Fixes:
077fcf116c8c ("mm/thp: allocate transparent hugepages on local node")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: <stable@vger.kernel.org> [4.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Josef Bacik [Wed, 24 Jun 2015 23:58:45 +0000 (16:58 -0700)]
tmpfs: truncate prealloc blocks past i_size
One of the rocksdb people noticed that when you do something like this
fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, 10M)
pwrite(fd, buf, 5M, 0)
ftruncate(5M)
on tmpfs, the file would still take up 10M: which led to super fun
issues because we were getting ENOSPC before we thought we should be
getting ENOSPC. This patch fixes the problem, and mirrors what all the
other fs'es do (and was agreed to be the correct behaviour at LSF).
I tested it locally to make sure it worked properly with the following
xfs_io -f -c "falloc -k 0 10M" -c "pwrite 0 5M" -c "truncate 5M" file
Without the patch we have "Blocks: 20480", with the patch we have the
correct value of "Blocks: 10240".
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhu Guihua [Wed, 24 Jun 2015 23:58:42 +0000 (16:58 -0700)]
mm/memory hotplug: print the last vmemmap region at the end of hot add memory
When hot add two nodes continuously, we found the vmemmap region info is
a bit messed. The last region of node 2 is printed when node 3 hot
added, like the following:
Initmem setup node 2 [mem 0x0000000000000000-0xffffffffffffffff]
On node 2 totalpages: 0
Built 2 zonelists in Node order, mobility grouping on. Total pages:
16090539
Policy zone: Normal
init_memory_mapping: [mem 0x40000000000-0x407ffffffff]
[mem 0x40000000000-0x407ffffffff] page 1G
[
ffffea1000000000-
ffffea10001fffff] PMD -> [
ffff8a077d800000-
ffff8a077d9fffff] on node 2
[
ffffea1000200000-
ffffea10003fffff] PMD -> [
ffff8a077de00000-
ffff8a077dffffff] on node 2
...
[
ffffea101f600000-
ffffea101f9fffff] PMD -> [
ffff8a074ac00000-
ffff8a074affffff] on node 2
[
ffffea101fa00000-
ffffea101fdfffff] PMD -> [
ffff8a074a800000-
ffff8a074abfffff] on node 2
Initmem setup node 3 [mem 0x0000000000000000-0xffffffffffffffff]
On node 3 totalpages: 0
Built 3 zonelists in Node order, mobility grouping on. Total pages:
16090539
Policy zone: Normal
init_memory_mapping: [mem 0x60000000000-0x607ffffffff]
[mem 0x60000000000-0x607ffffffff] page 1G
[
ffffea101fe00000-
ffffea101fffffff] PMD -> [
ffff8a074a400000-
ffff8a074a5fffff] on node 2 <=== node 2 ???
[
ffffea1800000000-
ffffea18001fffff] PMD -> [
ffff8a074a600000-
ffff8a074a7fffff] on node 3
[
ffffea1800200000-
ffffea18005fffff] PMD -> [
ffff8a074a000000-
ffff8a074a3fffff] on node 3
[
ffffea1800600000-
ffffea18009fffff] PMD -> [
ffff8a0749c00000-
ffff8a0749ffffff] on node 3
...
The cause is the last region was missed at the and of hot add memory,
and p_start, p_end, node_start were not reset, so when hot add memory to
a new node, it will consider they are not contiguous blocks and print
the previous one. So we print the last vmemmap region at the end of hot
add memory to avoid the confusion.
Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Piotr Kwapulinski [Wed, 24 Jun 2015 23:58:39 +0000 (16:58 -0700)]
mm/mmap.c: optimization of do_mmap_pgoff function
The simple check for zero length memory mapping may be performed
earlier. So that in case of zero length memory mapping some unnecessary
code is not executed at all. It does not make the code less readable
and saves some CPU cycles.
Signed-off-by: Piotr Kwapulinski <kwapulinski.piotr@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Catalin Marinas [Wed, 24 Jun 2015 23:58:37 +0000 (16:58 -0700)]
mm: kmemleak: optimise kmemleak_lock acquiring during kmemleak_scan
The kmemleak memory scanning uses finer grained object->lock spinlocks
primarily to avoid races with the memory block freeing. However, the
pointer lookup in the rb tree requires the kmemleak_lock to be held.
This is currently done in the find_and_get_object() function for each
pointer-like location read during scanning. While this allows a low
latency on kmemleak_*() callbacks on other CPUs, the memory scanning is
slower.
This patch moves the kmemleak_lock outside the scan_block() loop,
acquiring/releasing it only once per scanned memory block. The
allow_resched logic is moved outside scan_block() and a new
scan_large_block() function is implemented which splits large blocks in
MAX_SCAN_SIZE chunks with cond_resched() calls in-between. A redundant
(object->flags & OBJECT_NO_SCAN) check is also removed from
scan_object().
With this patch, the kmemleak scanning performance is significantly
improved: at least 50% with lock debugging disabled and over an order of
magnitude with lock proving enabled (on an arm64 system).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Catalin Marinas [Wed, 24 Jun 2015 23:58:34 +0000 (16:58 -0700)]
mm: kmemleak: avoid deadlock on the kmemleak object insertion error path
While very unlikely (usually kmemleak or sl*b bug), the create_object()
function in mm/kmemleak.c may fail to insert a newly allocated object into
the rb tree. When this happens, kmemleak disables itself and prints
additional information about the object already found in the rb tree.
Such printing is done with the parent->lock acquired, however the
kmemleak_lock is already held. This is a potential race with the scanning
thread which acquires object->lock and kmemleak_lock in a
This patch removes the locking around the 'parent' object information
printing. Such object cannot be freed or removed from object_tree_root
and object_list since kmemleak_lock is already held. There is a very
small risk that some of the object data is being modified on another CPU
but the only downside is inconsistent information printing.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Catalin Marinas [Wed, 24 Jun 2015 23:58:31 +0000 (16:58 -0700)]
mm: kmemleak: do not acquire scan_mutex in kmemleak_do_cleanup()
The kmemleak_do_cleanup() work thread already waits for the kmemleak_scan
thread to finish via kthread_stop(). Waiting in kthread_stop() while
scan_mutex is held may lead to deadlock if kmemleak_scan_thread() also
waits to acquire for scan_mutex.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Catalin Marinas [Wed, 24 Jun 2015 23:58:29 +0000 (16:58 -0700)]
mm: kmemleak: fix delete_object_*() race when called on the same memory block
Calling delete_object_*() on the same pointer is not a standard use case
(unless there is a bug in the code calling kmemleak_free()). However,
during kmemleak disabling (error or user triggered via /sys), there is a
potential race between kmemleak_free() calls on a CPU and
__kmemleak_do_cleanup() on a different CPU.
The current delete_object_*() implementation first performs a look-up
holding kmemleak_lock, increments the object->use_count and then
re-acquires kmemleak_lock to remove the object from object_tree_root and
object_list.
This patch simplifies the delete_object_*() mechanism to both look up
and remove an object from the object_tree_root and object_list
atomically (guarded by kmemleak_lock). This allows safe concurrent
calls to delete_object_*() on the same pointer without additional
locking for synchronising the kmemleak_free_enabled flag.
A side effect is a slight improvement in the delete_object_*() performance
by avoiding acquiring kmemleak_lock twice and incrementing/decrementing
object->use_count.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Catalin Marinas [Wed, 24 Jun 2015 23:58:26 +0000 (16:58 -0700)]
mm: kmemleak: allow safe memory scanning during kmemleak disabling
The kmemleak scanning thread can run for minutes. Callbacks like
kmemleak_free() are allowed during this time, the race being taken care
of by the object->lock spinlock. Such lock also prevents a memory block
from being freed or unmapped while it is being scanned by blocking the
kmemleak_free() -> ... -> __delete_object() function until the lock is
released in scan_object().
When a kmemleak error occurs (e.g. it fails to allocate its metadata),
kmemleak_enabled is set and __delete_object() is no longer called on
freed objects. If kmemleak_scan is running at the same time,
kmemleak_free() no longer waits for the object scanning to complete,
allowing the corresponding memory block to be freed or unmapped (in the
case of vfree()). This leads to kmemleak_scan potentially triggering a
page fault.
This patch separates the kmemleak_free() enabling/disabling from the
overall kmemleak_enabled nob so that we can defer the disabling of the
object freeing tracking until the scanning thread completed. The
kmemleak_free_part() is deliberately ignored by this patch since this is
only called during boot before the scanning thread started.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Vignesh Radhakrishnan <vigneshr@codeaurora.org>
Tested-by: Vignesh Radhakrishnan <vigneshr@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Wed, 24 Jun 2015 23:58:23 +0000 (16:58 -0700)]
memcg: convert mem_cgroup->under_oom from atomic_t to int
memcg->under_oom tracks whether the memcg is under OOM conditions and is
an atomic_t counter managed with mem_cgroup_[un]mark_under_oom(). While
atomic_t appears to be simple synchronization-wise, when used as a
synchronization construct like here, it's trickier and more error-prone
due to weak memory ordering rules, especially around atomic_read(), and
false sense of security.
For example, both non-trivial read sites of memcg->under_oom are a bit
problematic although not being actually broken.
* mem_cgroup_oom_register_event()
It isn't explicit what guarantees the memory ordering between event
addition and memcg->under_oom check. This isn't broken only because
memcg_oom_lock is used for both event list and memcg->oom_lock.
* memcg_oom_recover()
The lockless test doesn't have any explanation why this would be
safe.
mem_cgroup_[un]mark_under_oom() are very cold paths and there's no point
in avoiding locking memcg_oom_lock there. This patch converts
memcg->under_oom from atomic_t to int, puts their modifications under
memcg_oom_lock and documents why the lockless test in
memcg_oom_recover() is safe.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Wed, 24 Jun 2015 23:58:21 +0000 (16:58 -0700)]
memcg: remove unused mem_cgroup->oom_wakeups
Since commit
4942642080ea ("mm: memcg: handle non-error OOM situations
more gracefully"), nobody uses mem_cgroup->oom_wakeups. Remove it.
While at it, also fold memcg_wakeup_oom() into memcg_oom_recover() which
is its only user. This cleanup was suggested by Michal.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Streetman [Wed, 24 Jun 2015 23:58:18 +0000 (16:58 -0700)]
frontswap: allow multiple backends
Change frontswap single pointer to a singly linked list of frontswap
implementations. Update Xen tmem implementation as register no longer
returns anything.
Frontswap only keeps track of a single implementation; any
implementation that registers second (or later) will replace the
previously registered implementation, and gets a pointer to the previous
implementation that the new implementation is expected to pass all
frontswap functions to if it can't handle the function itself. However
that method doesn't really make much sense, as passing that work on to
every implementation adds unnecessary work to implementations; instead,
frontswap should simply keep a list of all registered implementations
and try each implementation for any function. Most importantly, neither
of the two currently existing frontswap implementations in the kernel
actually do anything with any previous frontswap implementation that
they replace when registering.
This allows frontswap to successfully manage multiple implementations by
keeping a list of them all.
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tony Luck [Wed, 24 Jun 2015 23:58:15 +0000 (16:58 -0700)]
x86, mirror: x86 enabling - find mirrored memory ranges
UEFI GetMemoryMap() uses a new attribute bit to mark mirrored memory
address ranges. See UEFI 2.5 spec pages 157-158:
http://www.uefi.org/sites/default/files/resources/UEFI%202_5.pdf
On EFI enabled systems scan the memory map and tell memblock about any
mirrored ranges.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xiexiuqi <xiexiuqi@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tony Luck [Wed, 24 Jun 2015 23:58:12 +0000 (16:58 -0700)]
mm/memblock: allocate boot time data structures from mirrored memory
Try to allocate all boot time kernel data structures from mirrored
memory.
If we run out of mirrored memory print warnings, but fall back to using
non-mirrored memory to make sure that we still boot.
By number of bytes, most of what we allocate at boot time is the page
structures. 64 bytes per 4K page on x86_64 ... or about 1.5% of total
system memory. For workloads where the bulk of memory is allocated to
applications this may represent a useful improvement to system
availability since 1.5% of total memory might be a third of the memory
allocated to the kernel.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xiexiuqi <xiexiuqi@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tony Luck [Wed, 24 Jun 2015 23:58:09 +0000 (16:58 -0700)]
mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute
Some high end Intel Xeon systems report uncorrectable memory errors as a
recoverable machine check. Linux has included code for some time to
process these and just signal the affected processes (or even recover
completely if the error was in a read only page that can be replaced by
reading from disk).
But we have no recovery path for errors encountered during kernel code
execution. Except for some very specific cases were are unlikely to ever
be able to recover.
Enter memory mirroring. Actually 3rd generation of memory mirroing.
Gen1: All memory is mirrored
Pro: No s/w enabling - h/w just gets good data from other side of the
mirror
Con: Halves effective memory capacity available to OS/applications
Gen2: Partial memory mirror - just mirror memory begind some memory controllers
Pro: Keep more of the capacity
Con: Nightmare to enable. Have to choose between allocating from
mirrored memory for safety vs. NUMA local memory for performance
Gen3: Address range partial memory mirror - some mirror on each memory
controller
Pro: Can tune the amount of mirror and keep NUMA performance
Con: I have to write memory management code to implement
The current plan is just to use mirrored memory for kernel allocations.
This has been broken into two phases:
1) This patch series - find the mirrored memory, use it for boot time
allocations
2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the
unused mirrored memory from mm/memblock.c and only give it out to
select kernel allocations (this is still being scoped because
page_alloc.c is scary).
This patch (of 3):
Add extra "flags" to memblock to allow selection of memory based on
attribute. No functional changes
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xiexiuqi <xiexiuqi@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Wed, 24 Jun 2015 23:58:06 +0000 (16:58 -0700)]
mm: do not ignore mapping_gfp_mask in page cache allocation paths
page_cache_read, do_generic_file_read, __generic_file_splice_read and
__ntfs_grab_cache_pages currently ignore mapping_gfp_mask when calling
add_to_page_cache_lru which might cause recursion into fs down in the
direct reclaim path if the mapping really relies on GFP_NOFS semantic.
This doesn't seem to be the case now because page_cache_read (page fault
path) doesn't seem to suffer from the reclaim recursion issues and
do_generic_file_read and __generic_file_splice_read also shouldn't be
called under fs locks which would deadlock in the reclaim path. Anyway it
is better to obey mapping gfp mask and prevent from later breakage.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Shailendra Verma [Wed, 24 Jun 2015 23:58:03 +0000 (16:58 -0700)]
mm/cma.c: fix typos in comments
Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wang Long [Wed, 24 Jun 2015 23:58:01 +0000 (16:58 -0700)]
mm/oom_kill.c: print points as unsigned int
In oom_kill_process(), the variable 'points' is unsigned int. Print it as
such.
Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike Kravetz [Wed, 24 Jun 2015 23:57:58 +0000 (16:57 -0700)]
mm/hugetlb: handle races in alloc_huge_page and hugetlb_reserve_pages
alloc_huge_page and hugetlb_reserve_pages use region_chg to calculate the
number of pages which will be added to the reserve map. Subpool and
global reserve counts are adjusted based on the output of region_chg.
Before the pages are actually added to the reserve map, these routines
could race and add fewer pages than expected. If this happens, the
subpool and global reserve counts are not correct.
Compare the number of pages actually added (region_add) to those expected
to added (region_chg). If fewer pages are actually added, this indicates
a race and adjust counters accordingly.
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike Kravetz [Wed, 24 Jun 2015 23:57:55 +0000 (16:57 -0700)]
mm/hugetlb: compute/return the number of regions added by region_add()
Modify region_add() to keep track of regions(pages) added to the reserve
map and return this value. The return value can be compared to the return
value of region_chg() to determine if the map was modified between calls.
Make vma_commit_reservation() also pass along the return value of
region_add(). In the normal case, we want vma_commit_reservation to
return the same value as the preceding call to vma_needs_reservation.
Create a common __vma_reservation_common routine to help keep the special
case return values in sync
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / linux-2.6-microblaze.git / log