summaryrefslogtreecommitdiff
path: root/drivers/md/bcache/writeback.c
AgeCommit message (Collapse)Author
2015-12-31bcache: Change refill_dirty() to always scan entire disk if necessaryKent Overstreet
Previously, it would only scan the entire disk if it was starting from the very start of the disk - i.e. if the previous scan got to the end. This was broken by refill_full_stripes(), which updates last_scanned so that refill_dirty was never triggering the searched_from_start path. But if we change refill_dirty() to always scan the entire disk if necessary, regardless of what last_scanned was, the code gets cleaner and we fix that bug too. Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-13bcache: remove driver private bio splitting codeKent Overstreet
The bcache driver has always accepted arbitrarily large bios and split them internally. Now that every driver must accept arbitrarily large bios this code isn't nessecary anymore. Cc: linux-bcache@vger.kernel.org Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> [dpark: add more description in commit message] Signed-off-by: Dongsu Park <dpark@posteo.net> Signed-off-by: Ming Lin <ming.l@ssi.samsung.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-29block: add a bi_error field to struct bioChristoph Hellwig
Currently we have two different ways to signal an I/O error on a BIO: (1) by clearing the BIO_UPTODATE flag (2) by returning a Linux errno value to the bi_end_io callback The first one has the drawback of only communicating a single possible error (-EIO), and the second one has the drawback of not beeing persistent when bios are queued up, and are not passed along from child to parent bio in the ever more popular chaining scenario. Having both mechanisms available has the additional drawback of utterly confusing driver authors and introducing bugs where various I/O submitters only deal with one of them, and the others have to add boilerplate code to deal with both kinds of error returns. So add a new bi_error field to store an errno value directly in struct bio and remove the existing mechanisms to clean all this up. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-08-04bcache: fix uninterruptible sleep in writeback threadSlava Pestov
There were two issues here: - writeback thread did not start until the device first became dirty - writeback thread used uninterruptible sleep once running Without this patch I see kernel warnings printed and a load average of 1.52 after booting my test VM. With this patch the warnings are gone and the load average is near 0.00 as expected. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-12-31Merge tag 'v3.13-rc6' into for-3.14/coreJens Axboe
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
2013-12-16bcache: New writeback PD controllerKent Overstreet
The old writeback PD controller could get into states where it had throttled all the way down and take way too long to recover - it was too complicated to really understand what it was doing. This rewrites a good chunk of it to hopefully be simpler and make more sense, and it also pays more attention to units which should make the behaviour a bit easier to understand. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-12-16bcache: Use uninterruptible sleep in writebackKent Overstreet
We're just waiting on kthread_should_stop(), nothing else, so interruptible sleep was wrong here. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-12-16bcache: kthread don't set writeback task to INTERUPTIBLEStefan Priebe
at the beginning (schedule_timout_interuptible) and others do his on their own This prevents wrong load average calculation (load of 1 per thread) Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-24block: Abstract out bvec iteratorKent Overstreet
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
2013-11-11bcache: Fix sysfs splat on shutdown with flash only devsKent Overstreet
Whoops. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-11bcache: Better full stripe scanningKent Overstreet
The old scanning-by-stripe code burned too much CPU, this should be better. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-11bcache: Convert bch_btree_insert() to bch_btree_map_leaf_nodes()Kent Overstreet
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>
2013-11-11bcache: Don't use op->insert_collisionKent Overstreet
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>
2013-11-11bcache: Kill op->replaceKent Overstreet
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>
2013-11-11bcache: Kill op->clKent Overstreet
This isn't used for waiting asynchronously anymore - so this is a fairly trivial refactoring. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-11bcache: Prune struct btree_opKent Overstreet
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>
2013-11-11bcache: Add btree_map() functionsKent Overstreet
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>
2013-11-11bcache: Convert writeback to a kthreadKent Overstreet
This simplifies the writeback flow control quite a bit - previously, it was conceptually two coroutines, refill_dirty() and read_dirty(). This makes the code quite a bit more straightforward. Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-11-11bcache: Move keylist out of btree_opKent Overstreet
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>
2013-11-11bcache: Add explicit keylist arg to btree_insert()Kent Overstreet
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>
2013-11-11bcache: Stripe size isn't necessarily a power of twoKent Overstreet
Originally I got this right... except that the divides didn't use do_div(), which broke 32 bit kernels. When I went to fix that, I forgot that the raid stripe size usually isn't a power of two... doh Signed-off-by: Kent Overstreet <kmo@daterainc.com>
2013-09-24bcache: Fix a dumb CPU spinning bug in writebackKent Overstreet
schedule_timeout() != schedule_timeout_uninterruptible() 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>
2013-09-24bcache: Fix a writeback performance regressionKent Overstreet
Background writeback works by scanning the btree for dirty data and adding those keys into a fixed size buffer, then for each dirty key in the keybuf writing it to the backing device. When read_dirty() finishes and it's time to scan for more dirty data, we need to wait for the outstanding writeback IO to finish - they still take up slots in the keybuf (so that foreground writes can check for them to avoid races) - without that wait, we'll continually rescan when we'll be able to add at most a key or two to the keybuf, and that takes locks that starves foreground IO. Doh. 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>
2013-07-01bcache: Use standard utility codeKent Overstreet
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>
2013-06-27bcache: Write out full stripesKent Overstreet
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>
2013-06-27bcache: Track dirty data by stripeKent Overstreet
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>
2013-06-27bcache: Initialize sectors_dirty when attachingKent Overstreet
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>
2013-06-27bcache: Fix/revamp tracepointsKent Overstreet
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>
2013-05-15bcache: Fix error handling in init codeKent Overstreet
This code appears to have rotted... fix various bugs and do some refactoring. Signed-off-by: Kent Overstreet <koverstreet@google.com>
2013-03-28bcache: Don't export utility code, prefix with bch_Kent Overstreet
Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: linux-bcache@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-23bcache: A block layer cacheKent Overstreet
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>