28 Jan, 2011
1 commit
-
In current rtmutex, the pending owner may be boosted by the tasks
in the rtmutex's waitlist when the pending owner is deboosted
or a task in the waitlist is boosted. This boosting is unrelated,
because the pending owner does not really take the rtmutex.
It is not reasonable.Example.
time1:
A(high prio) onwers the rtmutex.
B(mid prio) and C (low prio) in the waitlist.time2
A release the lock, B becomes the pending owner
A(or other high prio task) continues to run. B's prio is lower
than A, so B is just queued at the runqueue.time3
A or other high prio task sleeps, but we have passed some time
The B and C's prio are changed in the period (time2 ~ time3)
due to boosting or deboosting. Now C has the priority higher
than B. ***Is it reasonable that C has to boost B and help B to
get the rtmutex?NO!! I think, it is unrelated/unneed boosting before B really
owns the rtmutex. We should give C a chance to beat B and
win the rtmutex.This is the motivation of this patch. This patch *ensures*
only the top waiter or higher priority task can take the lock.How?
1) we don't dequeue the top waiter when unlock, if the top waiter
is changed, the old top waiter will fail and go to sleep again.
2) when requiring lock, it will get the lock when the lock is not taken and:
there is no waiter OR higher priority than waiters OR it is top waiter.
3) In any time, the top waiter is changed, the top waiter will be woken up.The algorithm is much simpler than before, no pending owner, no
boosting for pending owner.Other advantage of this patch:
1) The states of a rtmutex are reduced a half, easier to read the code.
2) the codes become shorter.
3) top waiter is not dequeued until it really take the lock:
they will retain FIFO when it is stolen.Not advantage nor disadvantage
1) Even we may wakeup multiple waiters(any time when top waiter changed),
we hardly cause "thundering herd",
the number of wokenup task is likely 1 or very little.
2) two APIs are changed.
rt_mutex_owner() will not return pending owner, it will return NULL when
the top waiter is going to take the lock.
rt_mutex_next_owner() always return the top waiter.
will not return NULL if we have waiters
because the top waiter is not dequeued.I have fixed the code that use these APIs.
need updated after this patch is accepted
1) Document/*
2) the testcase scripts/rt-tester/t4-l2-pi-deboost.tstSigned-off-by: Lai Jiangshan
LKML-Reference:
Reviewed-by: Steven Rostedt
Signed-off-by: Steven Rostedt
26 Jan, 2011
38 commits
-
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: wacom - pass touch resolution to clients through input_absinfo
Input: wacom - add 2 Bamboo Pen and touch models
Input: sysrq - ensure sysrq_enabled and __sysrq_enabled are consistent
Input: sparse-keymap - fix KEY_VSW handling in sparse_keymap_setup
Input: tegra-kbc - add tegra keyboard driver
Input: gpio_keys - switch to using request_any_context_irq
Input: serio - allow registered drivers to get status flag
Input: ct82710c - return proper error code for ct82c710_open
Input: bu21013_ts - added regulator support
Input: bu21013_ts - remove duplicate resolution parameters
Input: tnetv107x-ts - don't treat NULL clk as an error
Input: tnetv107x-keypad - don't treat NULL clk as an errorFix up trivial conflicts in drivers/input/keyboard/Makefile due to
additions of tc3589x/Tegra drivers -
Also remove fake ABS_RX/ABS_RY "axes" that were used to report physical
dimensions now that we have better way.Signed-off-by: Ping Cheng
Reviewed-by: Henrik Rydberg
Signed-off-by: Dmitry Torokhov -
The -rt patches change the console_semaphore to console_mutex. As a
result, a quite large chunk of the patches changes all
acquire/release_console_sem() to acquire/release_console_mutex()This commit makes things use more neutral function names which dont make
implications about the underlying lock.The only real change is the return value of console_trylock which is
inverted from try_acquire_console_sem()This patch also paves the way to switching console_sem from a semaphore to
a mutex.[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make console_trylock return 1 on success, per Geert]
Signed-off-by: Torben Hohn
Cc: Thomas Gleixner
Cc: Greg KH
Cc: Ingo Molnar
Cc: Geert Uytterhoeven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix potential use of uninitialised variable caused by recent
decompressor code optimisations.In zlib_uncompress (zlib_wrapper.c) we have
int zlib_err, zlib_init = 0;
...
do {
...
if (avail == 0) {
offset = 0;
put_bh(bh[k++]);
continue;
}
...
zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH);
...
} while (zlib_err == Z_OK);If continue is executed (avail == 0) then the while condition will be
evaluated testing zlib_err, which is uninitialised first time around the
loop.Fix this by getting rid of the 'if (avail == 0)' condition test, this
edge condition should not be being handled in the decompressor code, and
instead handle it generically in the caller code.Similarly for xz_wrapper.c.
Incidentally, on most architectures (bar Mips and Parisc), no
uninitialised variable warning is generated by gcc, this is because the
while condition test on continue is optimised out and not performed
(when executing continue zlib_err has not been changed since entering
the loop, and logically if the while condition was true previously, then
it's still true).Signed-off-by: Phillip Lougher
Reported-by: Jesper Juhl
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Executed command: fsstress -d /mnt -n 600 -p 850
crash> bt
PID: 7947 TASK: ffff880160546a70 CPU: 0 COMMAND: "fsstress"
#0 [ffff8800dfc07d00] machine_kexec at ffffffff81030db9
#1 [ffff8800dfc07d70] crash_kexec at ffffffff810a7952
#2 [ffff8800dfc07e40] oops_end at ffffffff814aa7c8
#3 [ffff8800dfc07e70] die_nmi at ffffffff814aa969
#4 [ffff8800dfc07ea0] do_nmi_callback at ffffffff8102b07b
#5 [ffff8800dfc07f10] do_nmi at ffffffff814aa514
#6 [ffff8800dfc07f50] nmi at ffffffff814a9d60
[exception RIP: __lookup_tag+100]
RIP: ffffffff812274b4 RSP: ffff88016056b998 RFLAGS: 00000287
RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000006
RDX: 000000000000001d RSI: ffff88016056bb18 RDI: ffff8800c85366e0
RBP: ffff88016056b9c8 R8: ffff88016056b9e8 R9: 0000000000000000
R10: 000000000000000e R11: ffff8800c8536908 R12: 0000000000000010
R13: 0000000000000040 R14: ffffffffffffffc0 R15: ffff8800c85366e0
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#7 [ffff88016056b998] __lookup_tag at ffffffff812274b4
#8 [ffff88016056b9d0] radix_tree_gang_lookup_tag_slot at ffffffff81227605
#9 [ffff88016056ba20] find_get_pages_tag at ffffffff810fc110
#10 [ffff88016056ba80] pagevec_lookup_tag at ffffffff81105e85
#11 [ffff88016056baa0] write_cache_pages at ffffffff81104c47
#12 [ffff88016056bbd0] generic_writepages at ffffffff81105014
#13 [ffff88016056bbe0] do_writepages at ffffffff81105055
#14 [ffff88016056bbf0] __filemap_fdatawrite_range at ffffffff810fb2cb
#15 [ffff88016056bc40] filemap_write_and_wait_range at ffffffff810fb32a
#16 [ffff88016056bc70] generic_file_direct_write at ffffffff810fb3dc
#17 [ffff88016056bce0] __generic_file_aio_write at ffffffff810fcee5
#18 [ffff88016056bda0] generic_file_aio_write at ffffffff810fd085
#19 [ffff88016056bdf0] do_sync_write at ffffffff8114f9ea
#20 [ffff88016056bf00] vfs_write at ffffffff8114fcf8
#21 [ffff88016056bf30] sys_write at ffffffff81150691
#22 [ffff88016056bf80] system_call_fastpath at ffffffff8100c0b2I think this root cause is the following:
radix_tree_range_tag_if_tagged() always tags the root tag with settag
if the root tag is set with iftag even if there are no iftag tags
in the specified range (Of course, there are some iftag tags
outside the specified range).===============================================================================
[[[Detailed description]]](1) Why cannot radix_tree_gang_lookup_tag_slot() return forever?
__lookup_tag():
- Return with 0.
- Return with the index which is not bigger than the old one as the
input parameter.Therefore the following "while" repeats forever because the above
conditions cause "ret" not to be updated and the cur_index cannot be
changed into the bigger one.(So, radix_tree_gang_lookup_tag_slot() cannot return forever.)
radix_tree_gang_lookup_tag_slot():
1178 while (ret < max_items) {
1179 unsigned int slots_found;
1180 unsigned long next_index; /* Index of next search */
1181
1182 if (cur_index > max_index)
1183 break;
1184 slots_found = __lookup_tag(node, results + ret,
1185 cur_index, max_items - ret, &next_index,
tag);
1186 ret += slots_found;
// cannot update ret because slots_found == 0.
// so, this while loops forever.
1187 if (next_index == 0)
1188 break;
1189 cur_index = next_index;
1190 }(2) Why does __lookup_tag() return with 0 and doesn't update the index?
Assuming the following:
- the one of the slot in radix_tree_node is NULL.
- the one of the tag which corresponds to the slot sets with
PAGECACHE_TAG_TOWRITE or other.
- In a certain height(!=0), the corresponding index is 0.a) __lookup_tag() notices that the tag is set.
1005 static unsigned int
1006 __lookup_tag(struct radix_tree_node *slot, void ***results, unsigned long index,
1007 unsigned int max_items, unsigned long *next_index, unsigned int tag)
1008 {
1009 unsigned int nr_found = 0;
1010 unsigned int shift, height;
1011
1012 height = slot->height;
1013 if (height == 0)
1014 goto out;
1015 shift = (height-1) * RADIX_TREE_MAP_SHIFT;
1016
1017 while (height > 0) {
1018 unsigned long i = (index >> shift) & RADIX_TREE_MAP_MASK ;
1019
1020 for (;;) {
1021 if (tag_get(slot, tag, i))
1022 break;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* the index is not updated yet.b) __lookup_tag() notices that the slot is NULL.
1023 index &= ~((1UL << shift) - 1);
1024 index += 1UL << shift;
1025 if (index == 0)
1026 goto out; /* 32-bit wraparound */
1027 i++;
1028 if (i == RADIX_TREE_MAP_SIZE)
1029 goto out;
1030 }
1031 height--;
1032 if (height == 0) { /* Bottom level: grab some items */
...
1055 }
1056 shift -= RADIX_TREE_MAP_SHIFT;
1057 slot = rcu_dereference_raw(slot->slots[i]);
1058 if (slot == NULL)
1059 break;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^c) __lookup_tag() doesn't update the index and return with 0.
1060 }
1061 out:
1062 *next_index = index;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1063 return nr_found;
1064 }(3) Why is the slot NULL even if the tag is set?
Because radix_tree_range_tag_if_tagged() always sets the root tag with
PAGECACHE_TAG_TOWRITE if the root tag is set with PAGECACHE_TAG_DIRTY,
even if there is no tag which can be set with PAGECACHE_TAG_TOWRITE
in the specified range (from *first_indexp to last_index). Of course,
some PAGECACHE_TAG_DIRTY nodes must exist outside the specified range.
(radix_tree_range_tag_if_tagged() is called only from tag_pages_for_writeback())640 unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root
*root,
641 unsigned long *first_indexp, unsigned long last_index,
642 unsigned long nr_to_tag,
643 unsigned int iftag, unsigned int settag)
644 {
645 unsigned int height = root->height;
646 struct radix_tree_path path[height];
647 struct radix_tree_path *pathp = path;
648 struct radix_tree_node *slot;
649 unsigned int shift;
650 unsigned long tagged = 0;
651 unsigned long index = *first_indexp;
652
653 last_index = min(last_index, radix_tree_maxindex(height));
654 if (index > last_index)
655 return 0;
656 if (!nr_to_tag)
657 return 0;
658 if (!root_tag_get(root, iftag)) {
659 *first_indexp = last_index + 1;
660 return 0;
661 }
662 if (height == 0) {
663 *first_indexp = last_index + 1;
664 root_tag_set(root, settag);
665 return 1;
666 }
...
733 root_tag_set(root, settag);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
734 *first_indexp = index;
735
736 return tagged;
737 }As the result, there is no radix_tree_node which is set with
PAGECACHE_TAG_TOWRITE but the root tag(radix_tree_root) is set with
PAGECACHE_TAG_TOWRITE.[figure: inside radix_tree]
(Please see the figure with typewriter font)
===========================================
[roottag = DIRTY]
| tag=0:NOTHING
tag[0 0 0 1] 1:DIRTY
[x x x +] 2:WRITEBACK
| 3:DIRTY,WRITEBACK
p 4:TOWRITE
5:DIRTY,TOWRITE ...
specified range (index: 0 to 2)* There is no DIRTY tag within the specified range.
(But there is a DIRTY tag outside that range.)| | | | | | | | |
after calling tag_pages_for_writeback()
| | | | | | | | |
v v v v v v v v v[roottag = DIRTY,TOWRITE]
| p is "page".
tag[0 0 0 1] x is NULL.
[x x x +] +- is a pointer to "page".
|
p* But TOWRITE tag is set on the root tag.
============================================After that, radix_tree_extend() via radix_tree_insert() is called
when the page is added.
This function sets the new radix_tree_node with PAGECACHE_TAG_TOWRITE
to succeed the status of the root tag.246 static int radix_tree_extend(struct radix_tree_root *root, unsigned long
index)
247 {
248 struct radix_tree_node *node;
249 unsigned int height;
250 int tag;
251
252 /* Figure out what the height should be. */
253 height = root->height + 1;
254 while (index > radix_tree_maxindex(height))
255 height++;
256
257 if (root->rnode == NULL) {
258 root->height = height;
259 goto out;
260 }
261
262 do {
263 unsigned int newheight;
264 if (!(node = radix_tree_node_alloc(root)))
265 return -ENOMEM;
266
267 /* Increase the height. */
268 node->slots[0] = radix_tree_indirect_to_ptr(root->rnode);
269
270 /* Propagate the aggregated tag info into the new root */
271 for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) {
272 if (root_tag_get(root, tag))
273 tag_set(node, tag, 0);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
274 }===========================================
[roottag = DIRTY,TOWRITE]
| :
tag[0 0 0 1] [0 0 0 0]
[x x x +] [+ x x x]
| |
p p (new page)| | | | | | | | |
after calling radix_tree_insert
| | | | | | | | |
v v v v v v v v v[roottag = DIRTY,TOWRITE]
|
tag [5 0 0 0] * DIRTY and TOWRITE tags are
[+ + x x] succeeded to the new node.
| |
tag [0 0 0 1] [0 0 0 0]
[x x x +] [+ x x x]
| |
p p
============================================After that, the index 3 page is released by remove_from_page_cache().
Then we can make the situation that the tag is set with PAGECACHE_TAG_TOWRITE
and that the slot which corresponds to the tag is NULL.
===========================================
[roottag = DIRTY,TOWRITE]
|
tag [5 0 0 0]
[+ + x x]
| |
tag [0 0 0 1] [0 0 0 0]
[x x x +] [+ x x x]
| |
p p
(remove)| | | | | | | | |
after calling remove_page_cache
| | | | | | | | |
v v v v v v v v v[roottag = DIRTY,TOWRITE]
|
tag [4 0 0 0] * Only DIRTY tag is cleared
[x + x x] because no TOWRITE tag is existed
| in the bottom node.
[0 0 0 0]
[+ x x x]
|
p
============================================To solve this problem
Change to that radix_tree_tag_if_tagged() doesn't tag the root tag
if it doesn't set any tags within the specified range.Like this.
============================================
640 unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root
*root,
641 unsigned long *first_indexp, unsigned long last_index,
642 unsigned long nr_to_tag,
643 unsigned int iftag, unsigned int settag)
644 {
650 unsigned long tagged = 0;
...
733 if (tagged)
^^^^^^^^^^^^^^^^^^^^^^^^
734 root_tag_set(root, settag);
735 *first_indexp = index;
736
737 return tagged;
738 }============================================
Signed-off-by: Toshiyuki Okajima
Acked-by: Jan Kara
Cc: Dave Chinner
Cc: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
setup_irq() was called before clockevents_register_device() which is
needed by the irq handler. Bug was reproducible by restarting the
kernel using kexec (reliable crash).Signed-off-by: Nikolaus Voss
Cc: David Brownell
Cc: Haavard Skinnemoen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
A fix up mem_cgroup_move_parent() which use compound_order() in
asynchronous manner. This compound_order() may return unknown value
because we don't take lock. Use PageTransHuge() and HPAGE_SIZE instead
of it.Also clean up for mem_cgroup_move_parent().
- remove unnecessary initialization of local variable.
- rename charge_size -> page_size
- remove unnecessary (wrong) comment.
- added a comment about THP.Note:
Current design take compound_page_lock() in caller of move_account().
This should be revisited when we implement direct move_task of hugepage
without splitting.[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki
Reviewed-by: Johannes Weiner
Acked-by: Daisuke Nishimura
Cc: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
mem_cgroup_disabled() should be checked at splitting. If disabled, no
heavy work is necesary.Signed-off-by: KAMEZAWA Hiroyuki
Acked-by: Daisuke Nishimura
Reviewed-by: Johannes Weiner
Cc: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Commit 4b53433468 ("memcg: clean up try_charge main loop") removes a
cancel of charge at case: memory charge-> success. mem+swap charge->
failure.This leaks usage of memory. Fix it.
Signed-off-by: KAMEZAWA Hiroyuki
Reviewed-by: Johannes Weiner
Acked-by: Daisuke Nishimura
Cc: Balbir Singh
Cc: [2.6.36+]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Callers of migrate_pages should putback_lru_pages to return pages
isolated to LRU or free list. Now comment is rather confusing. It says
caller always have to call it.It is more clear to point out that the caller has to call it if
migrate_pages's return value isn't zero.Signed-off-by: Minchan Kim
Cc: Christoph Lameter
Cc: Andrea Arcangeli
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Commit 5d6892407 ("thp: select CONFIG_COMPACTION if TRANSPARENT_HUGEPAGE
enabled") causes this warning during the configuration process:warning: (TRANSPARENT_HUGEPAGE) selects COMPACTION which has unmet
direct dependencies (EXPERIMENTAL && HUGETLB_PAGE && MMU)COMPACTION doesn't depend on HUGETLB_PAGE, it doesn't depend on THP
either, it is also useful for regular alloc_pages(order > 0) including
the very kernel stack during fork (THREAD_ORDER = 1). It's always
better to enable COMPACTION.The warning should be an error because we would end up with MIGRATION
not selected, and COMPACTION wouldn't work without migration (despite it
seems to build with an inline migrate_pages returning -ENOSYS).I'd also like to remove EXPERIMENTAL: compaction has been in the kernel
for some releases (for full safety the default remains disabled which I
think is enough).Signed-off-by: Andrea Arcangeli
Reported-by: Luca Tettamanti
Tested-by: Luca Tettamanti
Cc: Mel Gorman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In mm/memcontrol.c::mem_cgroup_move_parent() there's a path that jumps
to the 'put_back' labelret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false, charge);
if (ret || !parent)
goto put_back;where we'll
if (charge > PAGE_SIZE)
compound_unlock_irqrestore(page, flags);but, we have not assigned anything to 'flags' at this point, nor have we
called 'compound_lock_irqsave()' (which is what sets 'flags'). The
'put_back' label should be moved below the call to
compound_unlock_irqrestore() as per this patch.Signed-off-by: Jesper Juhl
Cc: Balbir Singh
Cc: Daisuke Nishimura
Cc: KAMEZAWA Hiroyuki
Cc: Pavel Emelianov
Cc: "Kirill A. Shutemov"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Commit 0e093d99763e ("writeback: do not sleep on the congestion queue if
there are no congested BDIs or if significant congestion is not being
encountered in the current zone") uncovered a livelock in the page
allocator that resulted in tasks infinitely looping trying to find
memory and kswapd running at 100% cpu.The issue occurs because drain_all_pages() is called immediately
following direct reclaim when no memory is freed and try_to_free_pages()
returns non-zero because all zones in the zonelist do not have their
all_unreclaimable flag set.When draining the per-cpu pagesets back to the buddy allocator for each
zone, the zone->pages_scanned counter is cleared to avoid erroneously
setting zone->all_unreclaimable later. The problem is that no pages may
actually be drained and, thus, the unreclaimable logic never fails
direct reclaim so the oom killer may be invoked.This apparently only manifested after wait_iff_congested() was
introduced and the zone was full of anonymous memory that would not
congest the backing store. The page allocator would infinitely loop if
there were no other tasks waiting to be scheduled and clear
zone->pages_scanned because of drain_all_pages() as the result of this
change before kswapd could scan enough pages to trigger the reclaim
logic. Additionally, with every loop of the page allocator and in the
reclaim path, kswapd would be kicked and would end up running at 100%
cpu. In this scenario, current and kswapd are all running continuously
with kswapd incrementing zone->pages_scanned and current clearing it.The problem is even more pronounced when current swaps some of its
memory to swap cache and the reclaimable logic then considers all active
anonymous memory in the all_unreclaimable logic, which requires a much
higher zone->pages_scanned value for try_to_free_pages() to return zero
that is never attainable in this scenario.Before wait_iff_congested(), the page allocator would incur an
unconditional timeout and allow kswapd to elevate zone->pages_scanned to
a level that the oom killer would be called the next time it loops.The fix is to only attempt to drain pcp pages if there is actually a
quantity to be drained. The unconditional clearing of
zone->pages_scanned in free_pcppages_bulk() need not be changed since
other callers already ensure that draining will occur. This patch
ensures that free_pcppages_bulk() will actually free memory before
calling into it from drain_all_pages() so zone->pages_scanned is only
cleared if appropriate.Signed-off-by: David Rientjes
Cc: Mel Gorman
Reviewed-by: Johannes Weiner
Cc: Minchan Kim
Cc: Wu Fengguang
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Reviewed-by: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Before 0e093d99763e ("writeback: do not sleep on the congestion queue if
there are no congested BDIs or if significant congestion is not being
encountered in the current zone"), preferred_zone was only used for NUMA
statistics, to determine the zoneidx from which to allocate from given
the type requested, and whether to utilize memory compaction.wait_iff_congested(), though, uses preferred_zone to determine if the
congestion wait should be deferred because its dirty pages are backed by
a congested bdi. This incorrectly defers the timeout and busy loops in
the page allocator with various cond_resched() calls if preferred_zone
is not allowed in the current context, usually consuming 100% of a cpu.This patch ensures preferred_zone is an allowed zone in the fastpath
depending on whether current is constrained by its cpuset or nodes in
its mempolicy (when the nodemask passed is non-NULL). This is correct
since the fastpath allocation always passes ALLOC_CPUSET when trying to
allocate memory. In the slowpath, this patch resets preferred_zone to
the first zone of the allowed type when the allocation is not
constrained by current's cpuset, i.e. it does not pass ALLOC_CPUSET.This patch also ensures preferred_zone is from the set of allowed nodes
when called from within direct reclaim since allocations are always
constrained by cpusets in this context (it is blockable).Both of these uses of cpuset_current_mems_allowed are protected by
get_mems_allowed().Signed-off-by: David Rientjes
Cc: Mel Gorman
Cc: Johannes Weiner
Cc: Minchan Kim
Cc: Wu Fengguang
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Acked-by: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Both pps_parport and pps_gen_parport are written in a way that they
can't share a port with any other driver. This can result in locking up
the process that loads modules or even the whole kernel if the modules
are compiled in. Use PARPORT_FLAG_EXCL to indicate this.Signed-off-by: Alexander Gordeev
Cc: Alexander Gordeev
Cc: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Signed-off-by: Rodolfo Giometti
Reported-by: Ingo Molnar
Cc: Alexander Gordeev
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
parport_unregister_device() should never be used when interrupts are
enabled in hardware and irq handler is registered so there is no need to
disable interrupts when using waitlist_lock. But there is no way to
explain this subtle semantics to lockdep analyzer.So disable interrupts here too to simplify things. The price is
negligible.Signed-off-by: Alexander Gordeev
Cc: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Latest kernel has many changes in IRQ subsystem and its interfaces, like
adding "irq_eoi" for struct irq_chip, this patch is a follow up change
for that.Also remove the unnecessary cast for a "void *".
Signed-off-by: Feng Tang
Cc: Alek Du
Cc: Alan Cox
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Return PTR_ERR(led_dat->pwm) instead of 0 if pwm_request failed
Signed-off-by: Axel Lin
Cc: Richard Purdie
Cc: Luotao Fu
Cc: Reviewed-by: Dmitry Torokhov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
mips (and sparc32):
In file included from arch/mips/include/asm/tlb.h:21,
from mm/pgtable-generic.c:9:
include/asm-generic/tlb.h: In function `tlb_flush_mmu':
include/asm-generic/tlb.h:76: error: implicit declaration of function `release_pages'
include/asm-generic/tlb.h: In function `tlb_remove_page':
include/asm-generic/tlb.h:105: error: implicit declaration of function `page_cache_release'free_pages_and_swap_cache() and free_page_and_swap_cache() are macros
which call release_pages() and page_cache_release(). The obvious fix is
to include pagemap.h in swap.h, where those macros are defined. But that
breaks sparc for weird reasons.So fix it within mm/pgtable-generic.c instead.
Reported-by: Yoichi Yuasa
Cc: Geert Uytterhoeven
Acked-by: Sam Ravnborg
Cc: Sergei Shtylyov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This fixes TRANSPARENT_HUGEPAGE=y with PARAVIRT=y and HIGHMEM64=n.
The #ifdef that this patch removes was erratically introduced to fix a
build error for noPAE (where pmd.pmd doesn't exist). So then the kernel
built but it failed at runtime because set_pmd_at was a noop. This will
correct it by enabling set_pmd_at for noPAE mode too.Signed-off-by: Andrea Arcangeli
Reported-by: werner
Reported-by: Minchan Kim
Tested-by: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
ALSA: AACI: fix timeout duration
ALSA: AACI: fix timeout condition checking
ARM: 6636/1: ep93xx: default multiplexed gpio ports to gpio mode
ARM: 6637/1: Make the argument to virt_to_phys() "const volatile"
ARM: twd: ensure timer reload is reprogrammed on entry to periodic mode
ARM: 6635/2: Configure reference clock for Versatile Express timers
ARM: versatile: name configuration options after actual board names
ARM: realview: name configuration options after actual board names
ARM: realview,vexpress: fix section mismatch warning for pen_release
ARM: 6632/3: mmci: stop using the blockend interrupts -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
nilfs2: fix crash after one superblock became unavailable -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k/amiga: Fix "debug=mem"
m68k/atari: Rename "scc" to "atari_scc"
m68k: Uninline strchr() -
…nel/git/lethal/sh-2.6
* 'rmobile-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
ARM: mach-shmobile: AG5EVM LCDC / MIPI-DSI platform data
ARM: mach-shmobile: sh73a0 CPGA fix for PLL CFG bit
ARM: mach-shmobile: mackerel: clarify shdi/mmcif switch settings
ARM: mach-shmobile: sh73a0 CPGA fix for IrDA MSTP
ARM: mach-shmobile: sh73a0 CPGA fix for FRQCRA M3
ARM: mach-shmobile: remove sh7367 on-chip set_irq_type()
ARM: mach-shmobile: sh7372 INTCS MFIS2 interrupt update
ARM: mach-shmobile: ag5evm: Add IrDA support
ARM: mach-shmobile: clock-sh7372: fixup pllc2 set_rate
mmc: sh_mmcif: Convert to __raw_xxx() I/O accessors.
ARM: mach-shmobile: ag5evm requires GPIOLIB
ARM: mach-shmobile: fix cpu_base of gic_init() on sh73a0 -
…l/git/lethal/fbdev-2.6
* 'fbdev-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-2.6:
mailmap: Add an entry for Axel Lin.
video: fix some comments in drivers/video/console/vgacon.c
drivers/video/bf537-lq035.c: Add missing IS_ERR test
video: pxa168fb: remove a redundant pxa168fb_check_var call
video: da8xx-fb: fix fb_probe error path
video: pxa3xx-gcu: Return -EFAULT when copy_from_user() fails
video: nuc900fb: properly free resources in nuc900fb_remove
video: nuc900fb: fix compile error -
* 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
sh: Fix build of sh7750 base boards
sh: update INTC to clear IRQ sense valid flag
sh: Fix sh build failure when CONFIG_SFC=m
sh: fix MSIOF0 SPI on ecovec: it conflicts with VOU
sh: support XZ-compressed kernel.
sh: Fix up breakage from asm-generic/pgtable.h changes. -
Fix __key_link_end()'s attempt to fix up the quota if an error occurs.
There are two erroneous cases: Firstly, we always decrease the quota if
the preallocated replacement keyring needs cleaning up, irrespective of
whether or not we should (we may have replaced a pointer rather than
adding another pointer).Secondly, we never clean up the quota if we added a pointer without the
keyring storage being extended (we allocate multiple pointers at a time,
even if we're not going to use them all immediately).We handle this by setting the bottom bit of the preallocation pointer in
__key_link_begin() to indicate that the quota needs fixing up, which is
then passed to __key_link() (which clears the whole thing) and
__key_link_end().Signed-off-by: David Howells
Signed-off-by: Linus Torvalds -
GPL V2 should be GPL v2
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
A B C D E ...
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
busy_loop() returns negative error code, thus change err variable
from u32 to int to properly propagate correct error code.Also remove unneeded initialization for err and i variables.
Signed-off-by: Axel Lin
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
Relying on the access time of peripherals is unreliable - it depends
on the speed of the CPU and the bus. On Versatile Express, these
timeouts were expiring, causing the driver to fail.Add udelay(1) to ensure that they don't expire early, and adjust
timeouts to give a reasonable margin over the response times.Signed-off-by: Russell King
-
Ensure that a timeout coincident with the condition being waited for
results in success rather than failure. This helps avoid timeout
conditions being inappropriately flagged.Signed-off-by: Russell King
-
The EP93xx C and D GPIO ports are multiplexed with the Keypad Interface
peripheral. At power-up they default into non-GPIO mode with the Key
Matrix controller enabled so these ports are unusable for GPIO. Note
that the Keypad Interface peripheral is only available in the EP9307,
EP9312, and EP9315 processor variants.The keypad support will clear the DeviceConfig bits appropriately to
enable the Keypad Interface when the driver is loaded. And, when the
driver is unloaded it will set the bits to return the ports to GPIO mode.To make these ports available for GPIO after power-up on all EP93xx
processor variants, set the KEYS and GONK bits in the DeviceConfig
register.Similarly, the E, G, and H ports are multiplexed with the IDE Interface
peripheral. At power-up these also default into non-GPIO mode. Note
that the IDE peripheral is only available in the EP9312 and EP9315
processor variants.Since an IDE driver is not even available in mainline, set the EONIDE,
GONIDE, and HONIDE bits in the DeviceConfig register so that these
ports will be available for GPIO use after power-up.Signed-off-by: H Hartley Sweeten
Acked-by: Ryan Mallon
Signed-off-by: Russell King -
Changing the virt_to_phys() argument to "const volatile void *" avoids
compiler warnings in some situations where this function is used.Signed-off-by: Catalin Marinas
Acked-by: Stephen Boyd
Acked-by: Arnd Bergmann
Signed-off-by: Russell King -
Ensure that the twd timer reload value is reprogrammed each time we
enter periodic mode. This ensures that the reload value is always
reset correctly.Tested-by: Santosh Shilimkar
Acked-by: Colin Cross
Signed-off-by: Russell King -
Timers on Versatile Express mainboard are used as system clock/event
sources. Driver assumes that they are clocked with 1MHz signal.
Old V2M firmware apparently configured it by default, but on newer
boards one can observe that "sleep 1" command takes over 30 seconds
to finish, as the timers are fed with 32kHz instead...This patch performs required magic and also removes code clearing
timer's control registers, as exactly the same operations are
performed by the timer driver few jiffies later.Signed-off-by: Pawel Moll
Tested-by: Will Deacon
Signed-off-by: Russell King
25 Jan, 2011
1 commit
-
Update the option text to those which appear on the front of the
appropriate board user guides. This gives consistent board naming, and
makes it obvious which option is for which platform.Acked-by: Catalin Marinas
Signed-off-by: Russell King