Commit Graph

148 Commits

Author SHA1 Message Date
Slava Pestov 2452cc8906 bcache: try to set b->parent properly
bcache_flash_dev.ktest would reliably crash with 8k and 16k bucket size
before; now it passes.

Change-Id: Ib542232235e39298c3a7548fe52b645cabb823d1
2014-08-04 15:23:04 -07:00
Slava Pestov 400ffaa2ac bcache: fix use-after-free in btree_gc_coalesce()
If we goto out_nocoalesce after we free new_nodes[0], we end up freeing
new_nodes[0] again. This was generating a lockdep warning. The fix is
to set new_nodes[0] to NULL, since the out_nocoalesce path safely
ignores NULL entries in the new_nodes array.

This regression was introduced in 2d7f9531.

Change-Id: I76564d7257800583214376b4bacf236cda90c89c
2014-08-04 15:23:04 -07:00
Slava Pestov 913dc33fb2 bcache: fix crash in bcache_btree_node_alloc_fail tracepoint
'b' was NULL.

Change-Id: Icac0fd04afa2d23f213d96d51afd53374e6dd0c0
2014-08-04 15:23:03 -07:00
Kent Overstreet 501d52a90c bcache: Allocate bounce buffers with GFP_NOWAIT
There's no point in blocking on these allocations, since our fallback paths will
probably go faster than blocking.

Change-Id: I733ca202c25cb36bde02607a0a60552229a4241c
2014-08-04 15:23:03 -07:00
Kent Overstreet bcf090e004 bcache: Make sure to pass GFP_WAIT to mempool_alloc()
this was very wrong - mempool_alloc() only guarantees success with GFP_WAIT.
bcache uses GFP_NOWAIT in various other places where we have a fallback,
circuits must've gotten crossed when writing this code or something.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-08-04 15:23:03 -07:00
Slava Pestov c5aa4a3157 bcache: wait for buckets when allocating new btree root
Tested:
- sometimes bcache_tier test would hang on startup with a failure
  to allocate the btree root -- no longer seeing this

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-08-04 15:23:03 -07:00
Kent Overstreet 3a2fd9d509 bcache: Kill bucket->gc_gen
gc_gen was a temporary used to recalculate last_gc, but since we only need
bucket->last_gc when gc isn't running (gc_mark_valid = 1), we can just update
last_gc directly.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:24:54 -07:00
Kent Overstreet 2531d9ee61 bcache: Kill unused freelist
This was originally added as at optimization that for various reasons isn't
needed anymore, but it does add a lot of nasty corner cases (and it was
responsible for some recently fixed bugs). Just get rid of it now.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:23:36 -07:00
Kent Overstreet 0a63b66db5 bcache: Rework btree cache reserve handling
This changes the bucket allocation reserves to use _real_ reserves - separate
freelists - instead of watermarks, which if nothing else makes the current code
saner to reason about and is going to be important in the future when we add
support for multiple btrees.

It also adds btree_check_reserve(), which checks (and locks) the reserves for
both bucket allocation and memory allocation for btree nodes; the old code just
kinda sorta assumed that since (e.g. for btree node splits) it had the root
locked and that meant no other threads could try to make use of the same
reserve; this technically should have been ok for memory allocation (we should
always have a reserve for memory allocation (the btree node cache is used as a
reserve and we preallocate it)), but multiple btrees will mean that locking the
root won't be sufficient anymore, and for the bucket allocation reserve it was
technically possible for the old code to deadlock.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:23:35 -07:00
Kent Overstreet 56b30770b2 bcache: Kill btree_io_wq
With the locking rework in the last patch, this shouldn't be needed anymore -
btree_node_write_work() only takes b->write_lock which is never held for very
long.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:23:35 -07:00
Kent Overstreet 2a285686c1 bcache: btree locking rework
Add a new lock, b->write_lock, which is required to actually modify - or write -
a btree node; this lock is only held for short durations.

This means we can write out a btree node without taking b->lock, which _is_ held
for long durations - solving a deadlock when btree_flush_write() (from the
journalling code) is called with a btree node locked.

Right now just occurs in bch_btree_set_root(), but with an upcoming journalling
rework is going to happen a lot more.

This also turns b->lock is now more of a read/intent lock instead of a
read/write lock - but not completely, since it still blocks readers. May turn it
into a real intent lock at some point in the future.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:23:35 -07:00
Kent Overstreet 05335cff9f bcache: Fix a race when freeing btree nodes
This isn't a bulletproof fix; btree_node_free() -> bch_bucket_free() puts the
bucket on the unused freelist, where it can be reused right away without any
ordering requirements. It would be better to wait on at least a journal write to
go down before reusing the bucket. bch_btree_set_root() does this, and inserting
into non leaf nodes is completely synchronous so we should be ok, but future
patches are just going to get rid of the unused freelist - it was needed in the
past for various reasons but shouldn't be anymore.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:23:34 -07:00
Kent Overstreet 4fe6a81670 bcache: Add a real GC_MARK_RECLAIMABLE
This means the garbage collection code can better check for data and metadata
pointers to the same buckets.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:22:36 -07:00
Kent Overstreet 3f5e0a34da bcache: Kill dead cgroup code
This hasn't been used or even enabled in ages.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:22:35 -07:00
Kent Overstreet 487dded86e bcache: Fix another bug recovering from unclean shutdown
The on disk bucket gens are allowed to be out of date, when we reuse buckets
that didn't have any live data in them. To deal with this, the initial gc has to
update the bucket gen when we find a pointer gen newer than the bucket's gen.

Unfortunately we weren't doing this for pointers in the journal that we're about
to replay.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:22:33 -07:00
Kent Overstreet 0bd143fd80 bcache: Fix a bug recovering from unclean shutdown
The code to fixup incorrect bucket prios incorrectly did not skip btree node
freeing keys

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-03-18 12:22:32 -07:00
Kent Overstreet 3572324af0 bcache: Minor fixes from kbuild robot
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-29 13:06:41 -08:00
Darrick J. Wong 9471744767 bcache: fix BUG_ON due to integer overflow with GC_SECTORS_USED
The BUG_ON at the end of __bch_btree_mark_key can be triggered due to
an integer overflow error:

BITMASK(GC_SECTORS_USED, struct bucket, gc_mark, 2, 13);
...
SET_GC_SECTORS_USED(g, min_t(unsigned,
	     GC_SECTORS_USED(g) + KEY_SIZE(k),
	     (1 << 14) - 1));
BUG_ON(!GC_SECTORS_USED(g));

In bcache.h, the SECTORS_USED bitfield is defined to be 13 bits wide.
While the SET_ code tries to ensure that the field doesn't overflow by
clamping it to (1<<14)-1 == 16383, this is incorrect because 16383
requires 14 bits.  Therefore, if GC_SECTORS_USED() + KEY_SIZE() =
8192, the SET_ statement tries to store 8192 into a 13-bit field.  In
a 13-bit field, 8192 becomes zero, thus triggering the BUG_ON.

Therefore, create a field width constant and a max value constant, and
use those to create the bitfield and check the inputs to
SET_GC_SECTORS_USED.  Arguably the BITMASK() template ought to have
BUG_ON checks for too-large values, but that's a separate patch.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2014-01-29 13:06:15 -08:00
Kent Overstreet 3b3e9e50dd bcache: Don't return -EINTR when insert finished
We need to return -EINTR after a split because we invalidated iterators
(and freed the btree node) - but if we were finished inserting, we don't
want to redo the traversal.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:14 -08:00
Kent Overstreet 829a60b905 bcache: Move insert_fixup() to btree_keys_ops
Now handling overlapping extents/keys is a method that's specific to what the
btree node contains.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:14 -08:00
Kent Overstreet 89ebb4a28b bcache: Convert sorting to btree_keys
More work to disentangle various code from struct btree

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:13 -08:00
Kent Overstreet dc9d98d621 bcache: Convert debug code to btree_keys
More work to disentangle various code from struct btree

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:13 -08:00
Kent Overstreet c052dd9a26 bcache: Convert btree_iter to struct btree_keys
More work to disentangle bset.c from struct btree

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:13 -08:00
Kent Overstreet 59158fde42 bcache: Add bch_btree_keys_u64s_remaining()
Helper function to explicitly check how much space is free in a btree node

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:13 -08:00
Kent Overstreet a85e968e66 bcache: Add struct btree_keys
Soon, bset.c won't need to depend on struct btree.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:13 -08:00
Kent Overstreet 65d45231b5 bcache: Abstract out stuff needed for sorting
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:12 -08:00
Kent Overstreet ee811287c9 bcache: Rename/shuffle various code around
More work to disentangle bset.c from the rest of the code:

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:12 -08:00
Kent Overstreet 67539e8528 bcache: Add struct bset_sort_state
More disentangling bset.c from the rest of the bcache code - soon, the
sorting routines won't have any dependencies on any outside structs.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:12 -08:00
Kent Overstreet 911c961009 bcache: Split out sort_extent_cmp()
Only use extent comparison for comparing extents, so we're not using
START_KEY() on other key types (i.e. btree pointers)

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:12 -08:00
Kent Overstreet fafff81cea bcache: Bkey indexing renaming
More refactoring:

node() -> bset_bkey_idx()
end() -> bset_bkey_last()

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:12 -08:00
Kent Overstreet 085d2a3dd4 bcache: Make bch_keylist_realloc() take u64s, not nptrs
Getting away from KEY_PTRS and moving toward KEY_U64s - and getting rid of magic
2s

Also - split out the part that checks against journal entry size so as to avoid
a dependancy on struct cache_set in bset.c

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:11 -08:00
Kent Overstreet 78b77bf8b2 bcache: Btree verify code improvements
Used this fixed code to find and fix the bug fixed by
a4d885097b0ac0cd1337f171f2d4b83e946094d4.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:10 -08:00
Kent Overstreet 88b9f8c426 bcache: kill index()
That was a terrible name for a macro, add some better helpers to replace it.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:10 -08:00
Kent Overstreet 5f5837d2d6 bcache: Do bkey_put() in btree_split() error path
This error path shouldn't have been hit in practice.. and we've got reworked
reserve code coming soon so that it shouldn't _ever_ be bit... but if we've got
code for this error path it should be correct.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:09 -08:00
Kent Overstreet 78365411b3 bcache: Rework allocator reserves
We need a reserve for allocating buckets for new btree nodes - and now that
we've got multiple btrees, it really needs to be per btree.

This reworks the reserves so we've got separate freelists for each reserve
instead of watermarks, which seems to make things a bit cleaner, and it adds
some code so that btree_split() can make sure the reserve is available before it
starts.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:09 -08:00
Kent Overstreet cb7a583e6a bcache: kill closure locking usage
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:08 -08:00
Kent Overstreet b0f32a56f2 bcache: Minor btree cache fix
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2014-01-08 13:05:07 -08:00
Jens Axboe b28bc9b38c Linux 3.13-rc6
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Merge tag 'v3.13-rc6' into for-3.14/core

Needed to bring blk-mq uptodate, since changes have been going in
since for-3.14/core was established.

Fixup merge issues related to the immutable biovec changes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

Conflicts:
	block/blk-flush.c
	fs/btrfs/check-integrity.c
	fs/btrfs/extent_io.c
	fs/btrfs/scrub.c
	fs/logfs/dev_bdev.c
2013-12-31 09:51:02 -07:00
Nicholas Swenson bf0a628a95 bcache: fix for gc and writeback race
Garbage collector needs to check keys in the writeback keybuf to
make sure it's not invalidating buckets to which the writeback
keys point to.

Signed-off-by: Nicholas Swenson <nks@daterainc.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-12-16 14:22:58 -08:00
Kent Overstreet d24a6e1087 bcache: Fix dirty_data accounting
Dirty data accounting wasn't quite right - firstly, we were adding the key we're
inserting after it could have merged with another dirty key already in the
btree, and secondly we could sometimes pass the wrong offset to
bcache_dev_sectors_dirty_add() for dirty data we were overwriting - which is
important when tracking dirty data by stripe.

NOTE FOR BACKPORTERS: For 3.10 (and 3.11?) there's other accounting fixes
necessary that got squashed in with other patches; the full patch against 3.10
is 408cc2f47eeac93a, available at:
  git://evilpiepirate.org/~kent/linux-bcache.git bcache-3.10-writeback-fixes

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10

diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 2a46036..4a12b2f 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -1817,7 +1817,8 @@ static bool fix_overlapping_extents(struct btree *b, struct bkey *insert,
 			if (KEY_START(k) > KEY_START(insert) + sectors_found)
 				goto check_failed;

-			if (KEY_PTRS(replace_key) != KEY_PTRS(k))
+			if (KEY_PTRS(k) != KEY_PTRS(replace_key) ||
+			    KEY_DIRTY(k) != KEY_DIRTY(replace_key))
 				goto check_failed;

 			/* skip past gen */
2013-12-16 14:22:16 -08:00
Wei Yongjun 08239ca2a0 bcache: fix sparse non static symbol warning
Fixes the following sparse warning:

drivers/md/bcache/btree.c:2220:5: warning:
 symbol 'btree_insert_fn' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-28 17:05:58 -08:00
Kent Overstreet 7988613b0e block: Convert bio_for_each_segment() to bvec_iter
More prep work for immutable biovecs - with immutable bvecs drivers
won't be able to use the biovec directly, they'll need to use helpers
that take into account bio->bi_iter.bi_bvec_done.

This updates callers for the new usage without changing the
implementation yet.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: Jim Paris <jim@jtan.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Cc: support@lsi.com
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Quoc-Son Anh <quoc-sonx.anh@intel.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
Cc: cbe-oss-dev@lists.ozlabs.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: DL-MPTFusionLinux@lsi.com
Cc: linux-scsi@vger.kernel.org
Cc: devel@driverdev.osuosl.org
Cc: linux-fsdevel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: linux-mm@kvack.org
Acked-by: Geoff Levand <geoff@infradead.org>
2013-11-23 22:33:49 -08:00
Kent Overstreet 4f024f3797 block: Abstract out bvec iterator
Immutable biovecs are going to require an explicit iterator. To
implement immutable bvecs, a later patch is going to add a bi_bvec_done
member to this struct; for now, this patch effectively just renames
things.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: Benny Halevy <bhalevy@tonian.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: xfs@oss.sgi.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchand@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peng Tao <tao.peng@emc.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: fanchaoting <fanchaoting@cn.fujitsu.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Pankaj Kumar <pankaj.km@samsung.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>6
2013-11-23 22:33:47 -08:00
Kent Overstreet 48a915a87f bcache: Better full stripe scanning
The old scanning-by-stripe code burned too much CPU, this should be
better.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:41 -08:00
Kent Overstreet 17e21a9f24 bcache: Have btree_split() insert into parent directly
The flow control in btree_insert_node() was... fragile... before,
this'll use more stack (but since our btrees are never more than depth
1, that shouldn't matter) and it should be significantly clearer and
less fragile.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:40 -08:00
Kent Overstreet 65d22e911b bcache: Move spinlock into struct time_stats
Minor cleanup.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:40 -08:00
Kent Overstreet 50310164bc bcache: Kill bch_next_recurse_key()
This dates from before the btree iterator, and now it's finally gone

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:39 -08:00
Kent Overstreet bc9389eefe bcache: Avoid deadlocking in garbage collection
Not a complete fix - we could still deadlock if btree_insert_node() has
to split...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:38 -08:00
Kent Overstreet a1f0358b2b bcache: Incremental gc
Big garbage collection rewrite; now, garbage collection uses the same
mechanisms as used elsewhere for inserting/updating btree node pointers,
instead of rewriting interior btree nodes in place.

This makes the code significantly cleaner and less fragile, and means we
can now make garbage collection incremental - it doesn't have to hold a
write lock on the root of the btree for the entire duration of garbage
collection.

This means that there's less of a latency hit for doing garbage
collection, which means we can gc more frequently (and do a better job
of reclaiming from the cache), and we can coalesce across more btree
nodes (improving our space efficiency).

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:37 -08:00
Kent Overstreet 8835c1234d bcache: Add make_btree_freeing_key()
Refactoring, prep work for incremental garbage collection.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:37 -08:00
Kent Overstreet f269af5a07 bcache: Add btree_node_write_sync()
More refactoring - mostly making the interfaces more explicit about what
we actually want to do.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:36 -08:00
Kent Overstreet 0eacac2203 bcache: PRECEDING_KEY()
btree_insert_key() was open coding this, this is just refactoring.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:36 -08:00
Kent Overstreet 3a3b6a4e07 bcache: Don't bother with bucket refcount for btree node allocations
The bucket refcount (dropped with bkey_put()) is only needed to prevent
the newly allocated bucket from being garbage collected until we've
added a pointer to it somewhere. But for btree node allocations, the
fact that we have btree nodes locked is enough to guard against races
with garbage collection.

Eventually the per bucket refcount is going to be replaced with
something specific to bch_alloc_sectors().

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:34 -08:00
Kent Overstreet 280481d06c bcache: Debug code improvements
Couple changes:
 * Consolidate bch_check_keys() and bch_check_key_order(), and move the
   checks that only check_key_order() could do to bch_btree_iter_next().

 * Get rid of CONFIG_BCACHE_EDEBUG - now, all that code is compiled in
   when CONFIG_BCACHE_DEBUG is enabled, and there's now a sysfs file to
   flip on the EDEBUG checks at runtime.

 * Dropped an old not terribly useful check in rw_unlock(), and
   refactored/improved a some of the other debug code.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:34 -08:00
Kent Overstreet 81ab4190ac bcache: Pull on disk data structures out into a separate header
Now, the on disk data structures are in a header that can be exported to
userspace - and having them all centralized is nice too.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:33 -08:00
Kent Overstreet cc7b881921 bcache: Convert bch_btree_insert() to bch_btree_map_leaf_nodes()
Last of the btree_map() conversions. Main visible effect is
bch_btree_insert() is no longer taking a struct btree_op as an argument
anymore - there's no fancy state machine stuff going on, it's just a
normal function.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:31 -08:00
Kent Overstreet 6054c6d4da bcache: Don't use op->insert_collision
When we convert bch_btree_insert() to bch_btree_map_leaf_nodes(), we
won't be passing struct btree_op to bch_btree_insert() anymore - so we
need a different way of returning whether there was a collision (really,
a replace collision).

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:30 -08:00
Kent Overstreet 1b207d80d5 bcache: Kill op->replace
This is prep work for converting bch_btree_insert to
bch_btree_map_leaf_nodes() - we have to convert all its arguments to
actual arguments. Bunch of churn, but should be straightforward.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:29 -08:00
Kent Overstreet faadf0c965 bcache: Drop some closure stuff
With a the recent bcache refactoring, some of the closure code isn't
needed anymore.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:10 -08:00
Kent Overstreet b54d6934da bcache: Kill op->cl
This isn't used for waiting asynchronously anymore - so this is a fairly
trivial refactoring.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:09 -08:00
Kent Overstreet c18536a72d bcache: Prune struct btree_op
Eventual goal is for struct btree_op to contain only what is necessary
for traversing the btree.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:08 -08:00
Kent Overstreet 2c1953e201 bcache: Convert bch_btree_read_async() to bch_btree_map_keys()
This is a fairly straightforward conversion, mostly reshuffling -
op->lookup_done goes away, replaced by MAP_DONE/MAP_CONTINUE. And the
code for handling cache hits and misses wasn't really btree code, so it
gets moved to request.c.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:07 -08:00
Kent Overstreet df8e89701f bcache: Move some stuff to btree.c
With the new btree_map() functions, we don't need to export the stuff
needed for traversing the btree anymore.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:07 -08:00
Kent Overstreet 48dad8baf9 bcache: Add btree_map() functions
Lots of stuff has been open coding its own btree traversal - which is
generally pretty simple code, but there are a few subtleties.

This adds new new functions, bch_btree_map_nodes() and
bch_btree_map_keys(), which do the traversal for you. Everything that's
open coding btree traversal now (with the exception of garbage
collection) is slowly going to be converted to these two functions;
being able to write other code at a higher level of abstraction  is a
big improvement w.r.t. overall code quality.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:06 -08:00
Kent Overstreet 72a44517f3 bcache: Convert gc to a kthread
We needed a dedicated rescuer workqueue for gc anyways... and gc was
conceptually a dedicated thread, just one that wasn't running all the
time. Switch it to a dedicated thread to make the code a bit more
straightforward.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:04 -08:00
Kent Overstreet 35fcd848d7 bcache: Convert bucket_wait to wait_queue_head_t
At one point we did do fancy asynchronous waiting stuff with
bucket_wait, but that's all gone (and bucket_wait is used a lot less
than it used to be). So use the standard primitives.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:04 -08:00
Kent Overstreet e8e1d4682c bcache: Convert try_wait to wait_queue_head_t
We never waited on c->try_wait asynchronously, so just use the standard
primitives.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:03 -08:00
Kent Overstreet 0b93207abb bcache: Move keylist out of btree_op
Slowly working on pruning struct btree_op - the aim is for it to only
contain things that are actually necessary for traversing the btree.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:02 -08:00
Kent Overstreet a34a8bfd4e bcache: Refactor journalling flow control
Making things less asynchronous that don't need to be - bch_journal()
only has to block when the journal or journal entry is full, which is
emphatically not a fast path. So make it a normal function that just
returns when it finishes, to make the code and control flow easier to
follow.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:02 -08:00
Kent Overstreet c2f95ae2eb bcache: Clean up keylist code
More random refactoring.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:56:00 -08:00
Kent Overstreet 4f3d40147b bcache: Add explicit keylist arg to btree_insert()
Some refactoring - better to explicitly pass stuff around instead of
having it all in the "big bag of state", struct btree_op. Going to prune
struct btree_op quite a bit over time.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:59 -08:00
Kent Overstreet e7c590eb63 bcache: Convert btree_insert_check_key() to btree_insert_node()
This was the main point of all this refactoring - now,
btree_insert_check_key() won't fail just because the leaf node happened
to be full.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:59 -08:00
Kent Overstreet 403b6cdeb1 bcache: Insert multiple keys at a time
We'll often end up with a list of adjacent keys to insert -
because bch_data_insert() may have to fragment the data it writes.

Originally, to simplify things and avoid having to deal with corner
cases bch_btree_insert() would pass keys from this list one at a time to
btree_insert_recurse() - mainly because the list of keys might span leaf
nodes, so it was easier this way.

With the btree_insert_node() refactoring, it's now a lot easier to just
pass down the whole list and have btree_insert_recurse() iterate over
leaf nodes until it's done.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:58 -08:00
Kent Overstreet 26c949f806 bcache: Add btree_insert_node()
The flow of control in the old btree insertion code was rather -
backwards; we'd recurse down the btree (in btree_insert_recurse()), and
then if we needed to split the keys to be inserted into the parent node
would be effectively returned up to btree_insert_recurse(), which would
notice there was more work to do and finish the insertion.

The main problem with this was that the full logic for btree insertion
could only be used by calling btree_insert_recurse; if you'd gotten to a
btree leaf some other way and had a key to insert, if it turned out that
node needed to be split you were SOL.

This inverts the flow of control so btree_insert_node() does _full_
btree insertion, including splitting - and takes a (leaf) btree node to
insert into as a parameter.

This means we can now _correctly_ handle cache misses - for cache
misses, we need to insert a fake "check" key into the btree when we
discover we have a cache miss - while we still have the btree locked.
Previously, if the btree node was full inserting a cache miss would just
fail.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:57 -08:00
Kent Overstreet d6fd3b11ce bcache: Explicitly track btree node's parent
This is prep work for the reworked btree insertion code.

The way we set b->parent is ugly and hacky... the problem is, when
btree_split() or garbage collection splits or rewrites a btree node, the
parent changes for all its (potentially already cached) children.

I may change this later and add some code to look through the btree node
cache and find all our cached child nodes and change the parent pointer
then...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-10 21:55:57 -08:00
Kent Overstreet 1fa8455deb bcache: Fix dirty_data accounting
Dirty data accounting wasn't quite right - firstly, we were adding the key we're
inserting after it could have merged with another dirty key already in the
btree, and secondly we could sometimes pass the wrong offset to
bcache_dev_sectors_dirty_add() for dirty data we were overwriting - which is
important when tracking dirty data by stripe.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-11-10 21:55:27 -08:00
Kent Overstreet a698e08c82 bcache: Fix a shrinker deadlock
GFP_NOIO means we could be getting called recursively - mca_alloc() ->
mca_data_alloc() - definitely can't use mutex_lock(bucket_lock) then.
Whoops.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Geert Uytterhoeven 61cbd250f8 bcache: Correct printf()-style format length modifier
Fix

  drivers/md/bcache/btree.c: In function ‘bch_btree_node_read’:
  drivers/md/bcache/btree.c:259: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 3 has type ‘size_t’

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Dave Chinner 7dc19d5aff drivers: convert shrinkers to new count/scan API
Convert the driver shrinkers to the new API.  Most changes are compile
tested only because I either don't have the hardware or it's staging
stuff.

FWIW, the md and android code is pretty good, but the rest of it makes me
want to claw my eyes out.  The amount of broken code I just encountered is
mind boggling.  I've added comments explaining what is broken, but I fear
that some of the code would be best dealt with by being dragged behind the
bike shed, burying in mud up to it's neck and then run over repeatedly
with a blunt lawn mower.

Special mention goes to the zcache/zcache2 drivers.  They can't co-exist
in the build at the same time, they are under different menu options in
menuconfig, they only show up when you've got the right set of mm
subsystem options configured and so even compile testing is an exercise in
pulling teeth.  And that doesn't even take into account the horrible,
broken code...

[glommer@openvz.org: fixes for i915, android lowmem, zcache, bcache]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10 18:56:32 -04:00
Kent Overstreet 29ebf465b9 bcache: Fix GC_SECTORS_USED() calculation
Part of the job of garbage collection is to add up however many sectors
of live data it finds in each bucket, but that doesn't work very well if
it doesn't reset GC_SECTORS_USED() when it starts. Whoops.

This wouldn't have broken anything horribly, but allocation tries to
preferentially reclaim buckets that are mostly empty and that's not
gonna work with an incorrect GC_SECTORS_USED() value.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
2013-07-12 00:22:48 -07:00
Kent Overstreet 8e51e414a3 bcache: Use standard utility code
Some of bcache's utility code has made it into the rest of the kernel,
so drop the bcache versions.

Bcache used to have a workaround for allocating from a bio set under
generic_make_request() (if you allocated more than once, the bios you
already allocated would get stuck on current->bio_list when you
submitted, and you'd risk deadlock) - bcache would mask out __GFP_WAIT
when allocating bios under generic_make_request() so that allocation
could fail and it could retry from workqueue. But bio_alloc_bioset() has
a workaround now, so we can drop this hack and the associated error
handling.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-07-01 14:43:53 -07:00
Kent Overstreet f3059a5461 bcache: Delete fuzz tester
This code has rotted and it hasn't been used in ages anyways.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-07-01 14:43:48 -07:00
Kent Overstreet 36c9ea9837 bcache: Document shrinker reserve better
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-07-01 14:42:48 -07:00
Kent Overstreet e49c7c374e bcache: FUA fixes
Journal writes need to be marked FUA, not just REQ_FLUSH. And btree node
writes have... weird ordering requirements.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-07-01 14:42:47 -07:00
Kent Overstreet 72c270612b bcache: Write out full stripes
Now that we're tracking dirty data per stripe, we can add two
optimizations for raid5/6:

 * If a stripe is already dirty, force writes to that stripe to
   writeback mode - to help build up full stripes of dirty data

 * When flushing dirty data, preferentially write out full stripes first
   if there are any.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 21:58:04 -07:00
Kent Overstreet 279afbad4e bcache: Track dirty data by stripe
To make background writeback aware of raid5/6 stripes, we first need to
track the amount of dirty data within each stripe - we do this by
breaking up the existing sectors_dirty into per stripe atomic_ts

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 21:57:23 -07:00
Kent Overstreet 444fc0b6b1 bcache: Initialize sectors_dirty when attaching
Previously, dirty_data wouldn't get initialized until the first garbage
collection... which was a bit of a problem for background writeback (as
the PD controller keys off of it) and also confusing for users.

This is also prep work for making background writeback aware of raid5/6
stripes.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:16 -07:00
Kent Overstreet 85b1492ee1 bcache: Rip out pkey()/pbtree()
Old gcc doesnt like the struct hack, and it is kind of ugly. So finish
off the work to convert pr_debug() statements to tracepoints, and delete
pkey()/pbtree().

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:15 -07:00
Kent Overstreet c37511b863 bcache: Fix/revamp tracepoints
The tracepoints were reworked to be more sensible, and fixed a null
pointer deref in one of the tracepoints.

Converted some of the pr_debug()s to tracepoints - this is partly a
performance optimization; it used to be that with DEBUG or
CONFIG_DYNAMIC_DEBUG pr_debug() was an empty macro; but at some point it
was changed to an empty inline function.

Some of the pr_debug() statements had rather expensive function calls as
part of the arguments, so this code was getting run unnecessarily even
on non debug kernels - in some fast paths, too.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:15 -07:00
Kent Overstreet 5794351146 bcache: Refactor btree io
The most significant change is that btree reads are now done
synchronously, instead of asynchronously and doing the post read stuff
from a workqueue.

This was originally done because we can't block on IO under
generic_make_request(). But - we already have a mechanism to punt cache
lookups to workqueue if needed, so if we just use that we don't have to
deal with the complexity of doing things asynchronously.

The main benefit is this makes the locking situation saner; we can hold
our write lock on the btree node until we're finished reading it, and we
don't need that btree_node_read_done() flag anymore.

Also, for writes, btree_write() was broken out into btree_node_write()
and btree_leaf_dirty() - the old code with the boolean argument was dumb
and confusing.

The prio_blocked mechanism was improved a bit too, now the only counter
is in struct btree_write, we don't mess with transfering a count from
struct btree anymore.

This required changing garbage collection to block prios at the start
and unblock when it finishes, which is cleaner than what it was doing
anyways (the old code had mostly the same effect, but was doing it in a
convoluted way)

And the btree iter btree_node_read_done() uses was converted to a real
mempool.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:14 -07:00
Kent Overstreet 119ba0f828 bcache: Convert allocator thread to kthread
Using a workqueue when we just want a single thread is a bit silly.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-06-26 17:09:13 -07:00
Kent Overstreet 86b26b824c bcache: Allocator cleanup/fixes
The main fix is that bch_allocator_thread() wasn't waiting on
garbage collection to finish (if invalidate_buckets had set
ca->invalidate_needs_gc); we need that to make sure the allocator
doesn't spin and potentially block gc from finishing.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-30 19:14:40 -07:00
Geert Uytterhoeven cd953ed036 bcache: Add missing #include <linux/prefetch.h>
m68k/allmodconfig:

drivers/md/bcache/bset.c: In function ‘bset_search_tree’:
drivers/md/bcache/bset.c:727: error: implicit declaration of function ‘prefetch’

drivers/md/bcache/btree.c: In function ‘bch_btree_node_get’:
drivers/md/bcache/btree.c:933: error: implicit declaration of function ‘prefetch’

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:48 -07:00
Kent Overstreet c19ed23a0b bcache: Sparse fixes
Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-04-08 13:33:48 -07:00
Kent Overstreet 169ef1cf61 bcache: Don't export utility code, prefix with bch_
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-28 12:50:55 -06:00
Kent Overstreet b1a67b0f4c bcache: Style/checkpatch fixes
Took out some nested functions, and fixed some more checkpatch
complaints.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-25 13:06:13 -06:00
Kent Overstreet 07e86ccb54 bcache: Build fixes from test robot
config: make ARCH=i386 allmodconfig

All error/warnings:

   drivers/md/bcache/bset.c: In function 'bch_ptr_bad':
>> drivers/md/bcache/bset.c:164:2: warning: format '%li' expects argument of type 'long int', but argument 4 has type 'size_t' [-Wformat]
--
   drivers/md/bcache/debug.c: In function 'bch_pbtree':
>> drivers/md/bcache/debug.c:86:4: warning: format '%li' expects argument of type 'long int', but argument 4 has type 'size_t' [-Wformat]
--
   drivers/md/bcache/btree.c: In function 'bch_btree_read_done':
>> drivers/md/bcache/btree.c:245:8: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'size_t' [-Wformat]
--
   drivers/md/bcache/closure.o: In function `closure_debug_init':
>> (.init.text+0x0): multiple definition of `init_module'
>> drivers/md/bcache/super.o:super.c:(.init.text+0x0): first defined here

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: linux-bcache@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-25 13:06:13 -06:00
Kent Overstreet cafe563591 bcache: A block layer cache
Does writethrough and writeback caching, handles unclean shutdown, and
has a bunch of other nifty features motivated by real world usage.

See the wiki at http://bcache.evilpiepirate.org for more.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-03-23 16:11:31 -07:00