OpenCloudOS-Kernel/drivers/md/bcache/writeback.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
// SPDX-License-Identifier: GPL-2.0
/*
* background writeback - scan btree for dirty data and write it to the backing
* device
*
* Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
* Copyright 2012 Google, Inc.
*/
#include "bcache.h"
#include "btree.h"
#include "debug.h"
#include "writeback.h"
#include <linux/delay.h>
#include <linux/kthread.h>
#include <linux/sched/clock.h>
#include <trace/events/bcache.h>
/* Rate limiting */
static void __update_writeback_rate(struct cached_dev *dc)
{
struct cache_set *c = dc->disk.c;
bcache: correct cache_dirty_target in __update_writeback_rate() __update_write_rate() uses a Proportion-Differentiation Controller algorithm to control writeback rate. A dirty target number is used in this PD controller to control writeback rate. A larger target number will make the writeback rate smaller, on the versus, a smaller target number will make the writeback rate larger. bcache uses the following steps to calculate the target number, 1) cache_sectors = all-buckets-of-cache-set * buckets-size 2) cache_dirty_target = cache_sectors * cached-device-writeback_percent 3) target = cache_dirty_target * (sectors-of-cached-device/sectors-of-all-cached-devices-of-this-cache-set) The calculation at step 1) for cache_sectors is incorrect, which does not consider dirty blocks occupied by flash only volume. A flash only volume can be took as a bcache device without cached device. All data sectors allocated for it are persistent on cache device and marked dirty, they are not touched by bcache writeback and garbage collection code. So data blocks of flash only volume should be ignore when calculating cache_sectors of cache set. Current code does not subtract dirty sectors of flash only volume, which results a larger target number from the above 3 steps. And in sequence the cache device's writeback rate is smaller then a correct value, writeback speed is slower on all cached devices. This patch fixes the incorrect slower writeback rate by subtracting dirty sectors of flash only volumes in __update_writeback_rate(). (Commit log composed by Coly Li to pass checkpatch.pl checking) Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn> Reviewed-by: Coly Li <colyli@suse.de> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-06 14:25:56 +08:00
uint64_t cache_sectors = c->nbuckets * c->sb.bucket_size -
bcache_flash_devs_sectors_dirty(c);
uint64_t cache_dirty_target =
div_u64(cache_sectors * dc->writeback_percent, 100);
int64_t target = div64_u64(cache_dirty_target * bdev_sectors(dc->bdev),
c->cached_dev_sectors);
/*
* PI controller:
* Figures out the amount that should be written per second.
*
* First, the error (number of sectors that are dirty beyond our
* target) is calculated. The error is accumulated (numerically
* integrated).
*
* Then, the proportional value and integral value are scaled
* based on configured values. These are stored as inverses to
* avoid fixed point math and to make configuration easy-- e.g.
* the default value of 40 for writeback_rate_p_term_inverse
* attempts to write at a rate that would retire all the dirty
* blocks in 40 seconds.
*
* The writeback_rate_i_inverse value of 10000 means that 1/10000th
* of the error is accumulated in the integral term per second.
* This acts as a slow, long-term average that is not subject to
* variations in usage like the p term.
*/
int64_t dirty = bcache_dev_sectors_dirty(&dc->disk);
int64_t error = dirty - target;
int64_t proportional_scaled =
div_s64(error, dc->writeback_rate_p_term_inverse);
int64_t integral_scaled;
uint32_t new_rate;
if ((error < 0 && dc->writeback_rate_integral > 0) ||
(error > 0 && time_before64(local_clock(),
dc->writeback_rate.next + NSEC_PER_MSEC))) {
/*
* Only decrease the integral term if it's more than
* zero. Only increase the integral term if the device
* is keeping up. (Don't wind up the integral
* ineffectively in either case).
*
* It's necessary to scale this by
* writeback_rate_update_seconds to keep the integral
* term dimensioned properly.
*/
dc->writeback_rate_integral += error *
dc->writeback_rate_update_seconds;
}
integral_scaled = div_s64(dc->writeback_rate_integral,
dc->writeback_rate_i_term_inverse);
new_rate = clamp_t(int32_t, (proportional_scaled + integral_scaled),
dc->writeback_rate_minimum, NSEC_PER_SEC);
dc->writeback_rate_proportional = proportional_scaled;
dc->writeback_rate_integral_scaled = integral_scaled;
dc->writeback_rate_change = new_rate - dc->writeback_rate.rate;
dc->writeback_rate.rate = new_rate;
dc->writeback_rate_target = target;
}
static void update_writeback_rate(struct work_struct *work)
{
struct cached_dev *dc = container_of(to_delayed_work(work),
struct cached_dev,
writeback_rate_update);
down_read(&dc->writeback_lock);
if (atomic_read(&dc->has_dirty) &&
dc->writeback_percent)
__update_writeback_rate(dc);
up_read(&dc->writeback_lock);
schedule_delayed_work(&dc->writeback_rate_update,
dc->writeback_rate_update_seconds * HZ);
}
static unsigned writeback_delay(struct cached_dev *dc, unsigned sectors)
{
if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) ||
!dc->writeback_percent)
return 0;
return bch_next_delay(&dc->writeback_rate, sectors);
}
struct dirty_io {
struct closure cl;
struct cached_dev *dc;
struct bio bio;
};
static void dirty_init(struct keybuf_key *w)
{
struct dirty_io *io = w->private;
struct bio *bio = &io->bio;
bio_init(bio, bio->bi_inline_vecs,
DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS));
if (!io->dc->writeback_percent)
bio_set_prio(bio, IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0));
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
2013-10-12 06:44:27 +08:00
bio->bi_iter.bi_size = KEY_SIZE(&w->key) << 9;
bio->bi_private = w;
bch_bio_map(bio, NULL);
}
static void dirty_io_destructor(struct closure *cl)
{
struct dirty_io *io = container_of(cl, struct dirty_io, cl);
kfree(io);
}
static void write_dirty_finish(struct closure *cl)
{
struct dirty_io *io = container_of(cl, struct dirty_io, cl);
struct keybuf_key *w = io->bio.bi_private;
struct cached_dev *dc = io->dc;
bio_free_pages(&io->bio);
/* This is kind of a dumb way of signalling errors. */
if (KEY_DIRTY(&w->key)) {
int ret;
unsigned i;
struct keylist keys;
bch_keylist_init(&keys);
bkey_copy(keys.top, &w->key);
SET_KEY_DIRTY(keys.top, false);
bch_keylist_push(&keys);
for (i = 0; i < KEY_PTRS(&w->key); i++)
atomic_inc(&PTR_BUCKET(dc->disk.c, &w->key, i)->pin);
ret = bch_btree_insert(dc->disk.c, &keys, NULL, &w->key);
if (ret)
trace_bcache_writeback_collision(&w->key);
atomic_long_inc(ret
? &dc->disk.c->writeback_keys_failed
: &dc->disk.c->writeback_keys_done);
}
bch_keybuf_del(&dc->writeback_keys, w);
up(&dc->in_flight);
closure_return_with_destructor(cl, dirty_io_destructor);
}
static void dirty_endio(struct bio *bio)
{
struct keybuf_key *w = bio->bi_private;
struct dirty_io *io = w->private;
if (bio->bi_status)
SET_KEY_DIRTY(&w->key, false);
closure_put(&io->cl);
}
static void write_dirty(struct closure *cl)
{
struct dirty_io *io = container_of(cl, struct dirty_io, cl);
struct keybuf_key *w = io->bio.bi_private;
/*
* IO errors are signalled using the dirty bit on the key.
* If we failed to read, we should not attempt to write to the
* backing device. Instead, immediately go to write_dirty_finish
* to clean up.
*/
if (KEY_DIRTY(&w->key)) {
dirty_init(w);
bio_set_op_attrs(&io->bio, REQ_OP_WRITE, 0);
io->bio.bi_iter.bi_sector = KEY_START(&w->key);
bio_set_dev(&io->bio, io->dc->bdev);
io->bio.bi_end_io = dirty_endio;
closure_bio_submit(&io->bio, cl);
}
continue_at(cl, write_dirty_finish, io->dc->writeback_write_wq);
}
static void read_dirty_endio(struct bio *bio)
{
struct keybuf_key *w = bio->bi_private;
struct dirty_io *io = w->private;
bch_count_io_errors(PTR_CACHE(io->dc->disk.c, &w->key, 0),
bio->bi_status, "reading dirty data from cache");
dirty_endio(bio);
}
static void read_dirty_submit(struct closure *cl)
{
struct dirty_io *io = container_of(cl, struct dirty_io, cl);
closure_bio_submit(&io->bio, cl);
continue_at(cl, write_dirty, io->dc->writeback_write_wq);
}
static void read_dirty(struct cached_dev *dc)
{
unsigned delay = 0;
struct keybuf_key *w;
struct dirty_io *io;
struct closure cl;
closure_init_stack(&cl);
/*
* XXX: if we error, background writeback just spins. Should use some
* mempools.
*/
while (!kthread_should_stop()) {
w = bch_keybuf_next(&dc->writeback_keys);
if (!w)
break;
BUG_ON(ptr_stale(dc->disk.c, &w->key, 0));
if (KEY_START(&w->key) != dc->last_read ||
jiffies_to_msecs(delay) > 50)
while (!kthread_should_stop() && delay)
delay = schedule_timeout_interruptible(delay);
dc->last_read = KEY_OFFSET(&w->key);
io = kzalloc(sizeof(struct dirty_io) + sizeof(struct bio_vec)
* DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS),
GFP_KERNEL);
if (!io)
goto err;
w->private = io;
io->dc = dc;
dirty_init(w);
bio_set_op_attrs(&io->bio, REQ_OP_READ, 0);
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
2013-10-12 06:44:27 +08:00
io->bio.bi_iter.bi_sector = PTR_OFFSET(&w->key, 0);
bio_set_dev(&io->bio, PTR_CACHE(dc->disk.c, &w->key, 0)->bdev);
io->bio.bi_end_io = read_dirty_endio;
if (bio_alloc_pages(&io->bio, GFP_KERNEL))
goto err_free;
trace_bcache_writeback(&w->key);
down(&dc->in_flight);
closure_call(&io->cl, read_dirty_submit, NULL, &cl);
delay = writeback_delay(dc, KEY_SIZE(&w->key));
}
if (0) {
err_free:
kfree(w->private);
err:
bch_keybuf_del(&dc->writeback_keys, w);
}
/*
* Wait for outstanding writeback IOs to finish (and keybuf slots to be
* freed) before refilling again
*/
closure_sync(&cl);
}
/* Scan for dirty data */
void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned inode,
uint64_t offset, int nr_sectors)
{
struct bcache_device *d = c->devices[inode];
unsigned stripe_offset, stripe, sectors_dirty;
if (!d)
return;
stripe = offset_to_stripe(d, offset);
stripe_offset = offset & (d->stripe_size - 1);
while (nr_sectors) {
int s = min_t(unsigned, abs(nr_sectors),
d->stripe_size - stripe_offset);
if (nr_sectors < 0)
s = -s;
if (stripe >= d->nr_stripes)
return;
sectors_dirty = atomic_add_return(s,
d->stripe_sectors_dirty + stripe);
if (sectors_dirty == d->stripe_size)
set_bit(stripe, d->full_dirty_stripes);
else
clear_bit(stripe, d->full_dirty_stripes);
nr_sectors -= s;
stripe_offset = 0;
stripe++;
}
}
static bool dirty_pred(struct keybuf *buf, struct bkey *k)
{
struct cached_dev *dc = container_of(buf, struct cached_dev, writeback_keys);
BUG_ON(KEY_INODE(k) != dc->disk.id);
return KEY_DIRTY(k);
}
static void refill_full_stripes(struct cached_dev *dc)
{
struct keybuf *buf = &dc->writeback_keys;
unsigned start_stripe, stripe, next_stripe;
bool wrapped = false;
stripe = offset_to_stripe(&dc->disk, KEY_OFFSET(&buf->last_scanned));
if (stripe >= dc->disk.nr_stripes)
stripe = 0;
start_stripe = stripe;
while (1) {
stripe = find_next_bit(dc->disk.full_dirty_stripes,
dc->disk.nr_stripes, stripe);
if (stripe == dc->disk.nr_stripes)
goto next;
next_stripe = find_next_zero_bit(dc->disk.full_dirty_stripes,
dc->disk.nr_stripes, stripe);
buf->last_scanned = KEY(dc->disk.id,
stripe * dc->disk.stripe_size, 0);
bch_refill_keybuf(dc->disk.c, buf,
&KEY(dc->disk.id,
next_stripe * dc->disk.stripe_size, 0),
dirty_pred);
if (array_freelist_empty(&buf->freelist))
return;
stripe = next_stripe;
next:
if (wrapped && stripe > start_stripe)
return;
if (stripe == dc->disk.nr_stripes) {
stripe = 0;
wrapped = true;
}
}
}
/*
* Returns true if we scanned the entire disk
*/
static bool refill_dirty(struct cached_dev *dc)
{
struct keybuf *buf = &dc->writeback_keys;
struct bkey start = KEY(dc->disk.id, 0, 0);
struct bkey end = KEY(dc->disk.id, MAX_KEY_OFFSET, 0);
struct bkey start_pos;
/*
* make sure keybuf pos is inside the range for this disk - at bringup
* we might not be attached yet so this disk's inode nr isn't
* initialized then
*/
if (bkey_cmp(&buf->last_scanned, &start) < 0 ||
bkey_cmp(&buf->last_scanned, &end) > 0)
buf->last_scanned = start;
if (dc->partial_stripes_expensive) {
refill_full_stripes(dc);
if (array_freelist_empty(&buf->freelist))
return false;
}
start_pos = buf->last_scanned;
bch_refill_keybuf(dc->disk.c, buf, &end, dirty_pred);
if (bkey_cmp(&buf->last_scanned, &end) < 0)
return false;
/*
* If we get to the end start scanning again from the beginning, and
* only scan up to where we initially started scanning from:
*/
buf->last_scanned = start;
bch_refill_keybuf(dc->disk.c, buf, &start_pos, dirty_pred);
return bkey_cmp(&buf->last_scanned, &start_pos) >= 0;
}
static int bch_writeback_thread(void *arg)
{
struct cached_dev *dc = arg;
bool searched_full_index;
bch_ratelimit_reset(&dc->writeback_rate);
while (!kthread_should_stop()) {
down_write(&dc->writeback_lock);
if (!atomic_read(&dc->has_dirty) ||
(!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) &&
!dc->writeback_running)) {
up_write(&dc->writeback_lock);
set_current_state(TASK_INTERRUPTIBLE);
if (kthread_should_stop())
return 0;
schedule();
continue;
}
searched_full_index = refill_dirty(dc);
if (searched_full_index &&
RB_EMPTY_ROOT(&dc->writeback_keys.keys)) {
atomic_set(&dc->has_dirty, 0);
cached_dev_put(dc);
SET_BDEV_STATE(&dc->sb, BDEV_STATE_CLEAN);
bch_write_bdev_super(dc, NULL);
}
up_write(&dc->writeback_lock);
read_dirty(dc);
if (searched_full_index) {
unsigned delay = dc->writeback_delay * HZ;
while (delay &&
!kthread_should_stop() &&
!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags))
delay = schedule_timeout_interruptible(delay);
bch_ratelimit_reset(&dc->writeback_rate);
}
}
return 0;
}
/* Init */
struct sectors_dirty_init {
struct btree_op op;
unsigned inode;
};
static int sectors_dirty_init_fn(struct btree_op *_op, struct btree *b,
struct bkey *k)
{
struct sectors_dirty_init *op = container_of(_op,
struct sectors_dirty_init, op);
if (KEY_INODE(k) > op->inode)
return MAP_DONE;
if (KEY_DIRTY(k))
bcache_dev_sectors_dirty_add(b->c, KEY_INODE(k),
KEY_START(k), KEY_SIZE(k));
return MAP_CONTINUE;
}
void bch_sectors_dirty_init(struct bcache_device *d)
{
struct sectors_dirty_init op;
bch_btree_op_init(&op.op, -1);
op.inode = d->id;
bch_btree_map_keys(&op.op, d->c, &KEY(op.inode, 0, 0),
sectors_dirty_init_fn, 0);
}
void bch_cached_dev_writeback_init(struct cached_dev *dc)
{
sema_init(&dc->in_flight, 64);
init_rwsem(&dc->writeback_lock);
bch_keybuf_init(&dc->writeback_keys);
dc->writeback_metadata = true;
dc->writeback_running = true;
dc->writeback_percent = 10;
dc->writeback_delay = 30;
dc->writeback_rate.rate = 1024;
dc->writeback_rate_minimum = 8;
dc->writeback_rate_update_seconds = 5;
dc->writeback_rate_p_term_inverse = 40;
dc->writeback_rate_i_term_inverse = 10000;
INIT_DELAYED_WORK(&dc->writeback_rate_update, update_writeback_rate);
}
int bch_cached_dev_writeback_start(struct cached_dev *dc)
{
dc->writeback_write_wq = alloc_workqueue("bcache_writeback_wq",
WQ_MEM_RECLAIM, 0);
if (!dc->writeback_write_wq)
return -ENOMEM;
dc->writeback_thread = kthread_create(bch_writeback_thread, dc,
"bcache_writeback");
if (IS_ERR(dc->writeback_thread))
return PTR_ERR(dc->writeback_thread);
schedule_delayed_work(&dc->writeback_rate_update,
dc->writeback_rate_update_seconds * HZ);
bch_writeback_queue(dc);
return 0;
}