The dirtied_when value on an inode is supposed to represent the first time
that an inode has one of its pages dirtied. This value is in units of
jiffies. It's used in several places in the writeback code to determine
when to write out an inode.
The problem is that these checks assume that dirtied_when is updated
periodically. If an inode is continuously being used for I/O it can be
persistently marked as dirty and will continue to age. Once the time
compared to is greater than or equal to half the maximum of the jiffies
type, the logic of the time_*() macros inverts and the opposite of what is
needed is returned. On 32-bit architectures that's just under 25 days
(assuming HZ == 1000).
As the least-recently dirtied inode, it'll end up being the first one that
pdflush will try to write out. sync_sb_inodes does this check:
/* Was this inode dirtied after sync_sb_inodes was called? */
if (time_after(inode->dirtied_when, start))
break;
...but now dirtied_when appears to be in the future. sync_sb_inodes bails
out without attempting to write any dirty inodes. When this occurs,
pdflush will stop writing out inodes for this superblock. Nothing can
unwedge it until jiffies moves out of the problematic window.
This patch fixes this problem by changing the checks against dirtied_when
to also check whether it appears to be in the future. If it does, then we
consider the value to be far in the past.
This should shrink the problematic window of time to such a small period
(30s) as not to matter.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Acked-by: Ian Kent <raven@themaw.net>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
filp->f_flags is unsigned, so use that type for the local copy.
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
clear_inode() will switch inode state from I_FREEING to I_CLEAR, and do so
_outside_ of inode_lock. So any I_FREEING testing is incomplete without a
coupled testing of I_CLEAR.
So add I_CLEAR tests to drop_pagecache_sb(), generic_sync_sb_inodes() and
add_dquot_ref().
Masayoshi MIZUMA discovered the bug in drop_pagecache_sb() and Jan Kara
reminds fixing the other two cases.
Masayoshi MIZUMA has a nice panic flow:
=====================================================================
[process A] | [process B]
| |
| prune_icache() | drop_pagecache()
| spin_lock(&inode_lock) | drop_pagecache_sb()
| inode->i_state |= I_FREEING; | |
| spin_unlock(&inode_lock) | V
| | | spin_lock(&inode_lock)
| V | |
| dispose_list() | |
| list_del() | |
| clear_inode() | |
| inode->i_state = I_CLEAR | |
| | | V
| | | if (inode->i_state & (I_FREEING|I_WILL_FREE))
| | | continue; <==== NOT MATCH
| | |
| | | (DANGER from here on! Accessing disposing inode!)
| | |
| | | __iget()
| | | list_move() <===== PANIC on poisoned list !!
V V |
(time)
=====================================================================
Reported-by: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a number of issues with the per-MM VMA patch:
(1) Make mmap_pages_allocated an atomic_long_t, just in case this is used on
a NOMMU system with more than 2G pages. Makes no difference on a 32-bit
system.
(2) Report vma->vm_pgoff * PAGE_SIZE as a 64-bit value, not a 32-bit value,
lest it overflow.
(3) Move the allocation of the vm_area_struct slab back for fork.c.
(4) Use KMEM_CACHE() for both vm_area_struct and vm_region slabs.
(5) Use BUG_ON() rather than if () BUG().
(6) Make the default validate_nommu_regions() a static inline rather than a
#define.
(7) Make free_page_series()'s objection to pages with a refcount != 1 more
informative.
(8) Adjust the __put_nommu_region() banner comment to indicate that the
semaphore must be held for writing.
(9) Limit the number of warnings about munmaps of non-mmapped regions.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes a build failure with generic debug pagealloc:
mm/debug-pagealloc.c: In function 'set_page_poison':
mm/debug-pagealloc.c:8: error: 'struct page' has no member named 'debug_flags'
mm/debug-pagealloc.c: In function 'clear_page_poison':
mm/debug-pagealloc.c:13: error: 'struct page' has no member named 'debug_flags'
mm/debug-pagealloc.c: In function 'page_poison':
mm/debug-pagealloc.c:18: error: 'struct page' has no member named 'debug_flags'
mm/debug-pagealloc.c: At top level:
mm/debug-pagealloc.c:120: error: redefinition of 'kernel_map_pages'
include/linux/mm.h:1278: error: previous definition of 'kernel_map_pages' was here
mm/debug-pagealloc.c: In function 'kernel_map_pages':
mm/debug-pagealloc.c:122: error: 'debug_pagealloc_enabled' undeclared (first use in this function)
by fixing
- debug_flags should be in struct page
- define DEBUG_PAGEALLOC config option for all architectures
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reported-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Copy/paste error. The RV670 microcode should work ok, so it's
not a show stopper.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Remove unused #include <version.h> in drivers/net/qlge/qlge_ethtool.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove unused #include <version.h> in drivers/net/dnet.c.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems that trivial reset of pcount to one was not sufficient
in tcp_retransmit_skb. Multiple counters experience a positive
miscount when skb's pcount gets lowered without the necessary
adjustments (depending on skb's sacked bits which exactly), at
worst a packets_out miscount can crash at RTO if the write queue
is empty!
Triggering this requires mss change, so bidir tcp or mtu probe or
like.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Uwe Bugla <uwe.bugla@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need full-scale adjustment to fix a TCP miscount in the next
patch, so just move it into a helper and call for that from the
other places.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some devices cannot send very short usb transfers. To get around this the
firmware adds a known pattern and flags the driver that it should check for
this pattern on short transfers. This flag was not taken into account by
the driver.
Signed-off-by: Jan Dumon <j.dumon@option.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changed the order in which things are freed. This fixes an oops when
unplugging the device while network traffic is ongoing.
Signed-off-by: Jan Dumon <j.dumon@option.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
EDIDs should be backward compatible, so don't bail if we see a version
of 3 (which is out there now) and print a message if we see something
newer, but allow it to be parsed.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Check whether the INTERLACE/DBLSCAN is supported by output device. If
not, the mode containing the flag of INTERLACE/DBLSCAN will be marked
as unsupported.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Should be,
edid_vendor[2] = (edid->mfg_id[1] & 0x1f) + '@';
Since vendor ID has only two bytes only, I am somewhat surprised why gcc
doesn't complain this.
Reported-by: Guo, Chaohong <chaohong.guo@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Remove an include that isn't actually needed to prevent needless
rebuilds.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The readq/writeq really need to be static inline on the arches which
don't provide them.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The commit:
platform driver: fix incorrect use of 'platform_bus_type' with 'struct device_driver'
contains this:
-static int __exit pxa2xx_flash_remove(struct device *dev)
+static int __exit pxa2xx_flash_remove(struct platform_device *dev)
...
- .remove = __exit_p(pxa2xx_flash_remove),
+ .remove = __devexit_p(pxa2xx_flash_remove),
which leads to the following build error:
`pxa2xx_flash_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o
This is not the only instance of it in this patch - all __exit_p's
touched by this patch have been converted to __devexit_p's without
regard to the original function.
Let's revert this change and, if we are going to convert functions
to be __devexit/__devinit, lets have that as a _separate_ patch doing
just that change.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Otherwise, the PAGE_CACHE_WC would end up getting us a UC-only mapping, and
the write performance of GTT maps dropped 10x.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[anholt: cleaned up unused var]
Signed-off-by: Eric Anholt <eric@anholt.net>
Add EXPORT_SYMBOL_GPL(fsl_pq_mdio_bus_name) for module builds
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set queue ordered mode. It doesn't really matter what we set here
because we don't ever put any requests on the queue. But we need to set
something other than QUEUE_ORDERED_NONE so that __generic_make_request
passes barrier requests to us.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move wait queue declaration and unplug to dm_wait_for_completion.
The purpose is to minimize duplicate code in the further patches.
The patch reorders functions a little bit. It doesn't change any
functionality. For proper non-deadlock operation, add_wait_queue must
happen before set_current_state(interruptible) and before the test for
!atomic_read(&md->pending).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Merge pushback and deferred lists into one list - use deferred list
for both deferred and pushed-back bios.
This will be needed for proper support of barrier bios: it is impossible to
support ordering correctly with two lists because the requests on both lists
will be mixed up.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Allow uninterruptible wait for pending IOs.
Add argument "interruptible" to dm_wait_for_completion that specifies
either interruptible or uninterruptible waiting.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Merge __flush_deferred_io() into the only caller, dm_wq_work().
There's no need to have a function that has only one caller.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move the bio_io_error() calls directly into __split_and_process_bio().
This avoids some code duplication in later patches.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Rename __split_bio() to __split_and_process_bio() because it not only splits
the bio to serveral parts, but also submits them to target drivers.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove struct dm_wq_req and move "work" directly into struct mapped_device.
In the revised implementation, the thread will do just one type of work
(processing the queue).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove the context field from struct dm_wq_req because we will no longer
need it.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove "type" field from struct dm_wq_req because we no longer need it
to have more than one value.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce a function that adds a bio to the head of the list for
use by the patch that will support barriers.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The persistent exception store destructor does not properly
account for all conditions in which it can be called. If it
is called after 'ctr' but before 'read_metadata' (e.g. if
something else in 'snapshot_ctr' fails) then it will attempt
to free areas of memory that haven't been allocated yet.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Let the exception store types print out their status through
the new API, rather than having the snapshot code do it.
Adjust the buffer position to allow for the preceding DMEMIT in the
arguments to type->status().
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
First step of having the exception stores parse their own arguments -
generalizing the interface.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use DMEMIT in place of snprintf. This makes it easier later when
other modules are helping to populate our status output.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move some of the last bits from dm-snap.h into dm-snap.c where they
belong and remove dm-snap.h.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move useful functions out of dm-snap.h and stop using dm-snap.h.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move COW device from snapshot to exception store.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move chunk fields from snapshot to exception store.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move target pointer from snapshot to exception store.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The logging API needs an extra function to make cluster mirroring
possible. This new function allows us to check whether a mirror
region is being recovered on another machine in the cluster. This
helps us prevent simultaneous recovery I/O and process I/O to the
same locations on disk.
Cluster-aware log modules will implement this function. Single
machine log modules will not. So, there is no performance
penalty for single machine mirrors.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Acked-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove the 'dm_dirty_log_internal' structure. The resulting cleanup
eliminates extra memory allocations. Therefore exposing the internal
list_head to the external 'dm_dirty_log_type' structure is a worthwhile
compromise.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Avoid private module usage accounting by removing 'use' from
dm_dirty_log_internal. The standard module reference counting is
sufficient.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use kzfree() instead of memset() + kfree().
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Jeff Layton
Andrew Morton
Wu Fengguang
David Howells
Sergey Senozhatsky
Akinobu Mita
Alex Deucher
Dave Airlie
Jesse Barnes
Huang Weiyi
Ilpo Järvinen
Jan Dumon
yakui_zhao
Jean Delvare
Russell King
Segher Boessenkool
Mikulas Patocka
Jonathan Brassow
Mike Snitzer
Johannes Weiner